JP7621072B2 - Manufacturing method of hollow structure and manufacturing method of hollow package - Google Patents

Description

The present invention relates to a method for manufacturing a hollow structure and a method for manufacturing a hollow package.

In recent years, the development of microelectronic devices such as surface acoustic wave (SAW) filters has progressed. Packages that encapsulate such electronic devices have a hollow structure to ensure the propagation of surface acoustic waves and the mobility of movable parts of the electronic devices.
A photosensitive resin composition is used to form the hollow structure, and a package is manufactured by molding the wiring board on which the electrodes are formed while maintaining the hollow structure.

For example, Patent Document 1 discloses a method for manufacturing a hollow package that includes a process for producing a hollow structure by forming a cavity securing portion so as to cover Micro Electro Mechanical Systems (MEMS) formed on a substrate, and a process for sealing the entire hollow structure with a sealing layer by transfer molding.

The cavity securing portion is formed as follows.
After a photosensitive resin composition is applied around the MEMS, exposure is performed through a photomask, post-exposure baking (PEB) and development are performed to form side walls.
Next, the cover film is peeled off from the dry film resist, which is made of a base film, a photosensitive resin composition layer, and a cover film laminated in that order, and the resulting film is laminated above the side wall to form a top plate portion. Exposure, PEB, and development are then performed again through a photomask, and unnecessary portions are removed to form a cavity securing portion.

WO 2009/151050

When producing a hollow structural body, generally, the cavity-reserving portion after development is further subjected to a heat treatment (curing operation) at a high temperature of, for example, 200° C. or higher in order to increase the strength of the cured film of the photosensitive resin composition layer.
However, the method for producing a hollow structural body described in Patent Document 1 has a problem in that the film-like top plate portion is easily deformed by the curing operation when the cavity securing portion is formed.

In addition, as the development of microelectronic devices progresses, there is currently a demand for modules to be made even thinner, and therefore, in the above-mentioned package, it is necessary to miniaturize the hollow structure while ensuring space in the vicinity of the electrodes formed on the wiring substrate.
However, when attempting to miniaturize the hollow structure in this manner, the strength of a cured film obtained by curing a conventional negative photosensitive resin composition or photosensitive resist film is insufficient, and it may become difficult to maintain the hollow structure against, for example, the high pressure applied during molding.

The present invention was made in consideration of the above circumstances, and aims to provide a method for manufacturing a hollow structure and a method for manufacturing a hollow package that can stably manufacture hollow structures with increased strength while suppressing deformation of the top plate due to the curing operation.

In order to solve the above problems, the present invention employs the following configuration.
That is, a first aspect of the present invention is a method for producing a hollow structural body comprising a recess and a top plate portion covering an opening of the recess, the method comprising the steps of: preparing a substrate having a recess on its surface; and a photosensitive resist film having a negative photosensitive resin film containing an epoxy group-containing resin (A) and a photoinitiator (I) that generates an acid upon exposure; arranging the photosensitive resist film so that the surface of the photosensitive resin film of the photosensitive resist film covers the opening of the recess in the substrate; exposing the photosensitive resin film after the step (i); and exposing the photosensitive resin film to light after the step (ii). This method for producing a hollow structure includes a step (iii) of performing a heat treatment, a step (iv) of developing the photosensitive resin film after the step (iii) to form a negative pattern, and a step (v) of further performing a heat treatment on the negative pattern after the step (iv) to harden it, thereby obtaining a hollow structure whose top plate portion is made of the hardened product of the photosensitive resin film, characterized in that the heat treatment in the step (v) is performed by heating at a temperature of 150°C or less for 10 minutes or more, followed by an operation (x) of further heating at a temperature exceeding 150°C, or an operation (y) of irradiating with ultraviolet light and then heating at a temperature of 100°C or higher.

The second aspect of the present invention is a method for producing a hollow package, characterized by having a step of sealing the hollow structure produced by the production method according to the first aspect with a sealing material to obtain a hollow package.

The present invention provides a method for manufacturing a hollow structure and a method for manufacturing a hollow package that can stably manufacture hollow structures with improved strength while suppressing deformation of the top plate due to the curing operation.

2A to 2C are schematic diagrams illustrating a method for manufacturing a hollow structure according to the first embodiment.

In this specification and the claims, the term "aliphatic" is a relative concept to aromaticity and is defined as meaning a group or compound that does not have aromaticity.
Unless otherwise specified, the term "alkyl group" includes linear, branched and cyclic monovalent saturated hydrocarbon groups. The same applies to the alkyl group in an alkoxy group.
Unless otherwise specified, the term "alkylene group" includes linear, branched and cyclic divalent saturated hydrocarbon groups.
The term "halogenated alkyl group" refers to an alkyl group in which some or all of the hydrogen atoms have been substituted with halogen atoms, and examples of the halogen atoms include fluorine, chlorine, bromine and iodine atoms.
The term "fluorinated alkyl group" refers to an alkyl group in which some or all of the hydrogen atoms have been substituted with fluorine atoms.
The term "structural unit" refers to a monomer unit that constitutes a polymeric compound (resin, polymer, copolymer).
The phrase "optionally having a substituent" includes both the case where a hydrogen atom (-H) is replaced with a monovalent group and the case where a methylene group (-CH ₂ -) is replaced with a divalent group.
The term "exposure" is intended to include any concept including irradiation with radiation.

(Method of manufacturing hollow structure)
The manufacturing method according to the first aspect of the present invention is a method for manufacturing a hollow structural body comprising a recess and a top plate portion for closing the opening of the recess, and includes the following step (0) and steps (i) to (v). In addition, in the manufacturing method according to the first aspect, the heat treatment in step (v) is performed by heating at a temperature of 150° C. or less for 10 minutes or more, followed by an operation (x) of heating at a temperature exceeding 150° C., or by an operation (y) of irradiating with ultraviolet light and then heating at a temperature of 100° C. or more.

Step (0): preparing a substrate having a recess on its surface, and a photosensitive resist film having a negative photosensitive resin film containing an epoxy group-containing resin (A) and a photoinitiator (I) that generates an acid upon exposure; Step (i): arranging the photosensitive resist film so that the surface of the photosensitive resin film of the photosensitive resist film covers the opening of the recess in the substrate; Step (ii): exposing the photosensitive resin film after step (i); Step (iii): subjecting the photosensitive resin film after step (ii) to a heat treatment; Step (iv): developing the photosensitive resin film after step (iii) to form a negative pattern; Step (v): further subjecting the negative pattern after step (iv) to a heat treatment to harden the pattern, thereby obtaining a hollow structural body whose top plate portion is made of a hardened product of the photosensitive resin film.

The hollow structure manufactured by the manufacturing method according to this embodiment comprises a recess and a top plate that covers the opening of the recess. The hollow structure can be suitably used for hollow packages used in SAW filters, MEMS, various sensors, etc.

[Step (0)]
In step (0) of this embodiment, a substrate having a recess on its surface and a photosensitive resist film having a negative photosensitive resin film containing an epoxy group-containing resin (A) and a photoinitiator (I) that generates an acid upon exposure are prepared.

<Substrates with concave portions on the surface>
Examples of substrates having a recess on their surface include structures in which a pattern is formed on a substrate, stepped substrates, etc. The recess may be made of either an organic material or an inorganic material.
Such a substrate having a recess on its surface can be manufactured by a method including, for example, a step of forming a photosensitive resin film on a support using a negative photosensitive resin composition (hereinafter referred to as a "film forming step"), a step of exposing the photosensitive resin film (hereinafter referred to as an "exposure step"), and a step of developing the exposed photosensitive resin film with a developer containing an organic solvent to form a negative pattern that will become the sidewall of the recess (hereinafter referred to as a "development step"). The method for manufacturing such a substrate having a recess on its surface can be carried out as follows.

Film formation process:
First, a negative photosensitive resin composition is applied onto a support by a known method such as spin coating, roll coating, or screen printing, and then baked (post-applied bake (PAB)) for 2 to 60 minutes at a temperature of, for example, 50 to 150° C. to form a photosensitive resin film.
The film-forming step can also be performed by disposing a photosensitive resin composition layer, which has been prepared in advance using a negative photosensitive resin composition, on a support.

The support is not particularly limited, and any conventionally known support can be used. For example, a substrate for electronic components, a substrate having a predetermined wiring pattern formed thereon, and the like can be mentioned.
More specifically, examples of substrates for electronic components include metal substrates such as silicon, silicon nitride, titanium, tantalum, lithium tantalate ( _LiTaO3 ), niobium, lithium niobate ( _LiNbO3 ), palladium, titanium tungsten, copper, chromium, iron, and aluminum, as well as glass substrates.
The wiring pattern may be made of a material such as copper, aluminum, nickel, or gold.

The thickness of the photosensitive resin film formed from the negative photosensitive resin composition is not particularly limited, but is preferably about 10 to 100 μm.

Exposure process:
Next, the formed photosensitive resin film is selectively exposed using a known exposure device, for example, by exposure through a mask (mask pattern) having a predetermined pattern formed thereon, or by drawing by direct irradiation with an electron beam without using a mask pattern, and then baked (post-exposure bake (PEB)) as necessary, for example, at a temperature condition of 80 to 150° C. for 40 to 1200 seconds, preferably 40 to 1000 seconds, and more preferably 60 to 900 seconds.

The wavelength used for exposure is not particularly limited, and radiation such as ultraviolet light having a wavelength of 300 to 500 nm, i-line (wavelength 365 nm), or visible light is selectively irradiated (exposed). As the radiation source, a low pressure mercury lamp, a high pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, an argon gas laser, etc. can be used.
Here, radiation means ultraviolet light, visible light, far ultraviolet light, X-rays, electron beams, etc. The radiation dose varies depending on the type and amount of each component in the composition, the thickness of the coating film, etc., but for example, when an ultra-high pressure mercury lamp is used, it is 100 to 2000 mJ/ ^cm2 .

The exposure method for the photosensitive resin film may be a normal exposure method (dry exposure) performed in air or an inert gas such as nitrogen, or it may be liquid immersion exposure (Liquid Immersion Lithography).

Development process:
Next, the photosensitive resin film after the exposure is developed with a developer containing an organic solvent (organic developer). After the development, a rinse treatment is preferably performed. If necessary, a bake treatment (post-bake) may be performed.

The organic solvent contained in the organic developer can be appropriately selected from known organic solvents. Specific examples include polar solvents such as ketone solvents, ester solvents, alcohol solvents, nitrile solvents, amide solvents, and ether solvents, and hydrocarbon solvents.

Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonylacetone, ionone, diacetonyl alcohol, acetylcarbinol, acetophenone, methyl naphthyl ketone, isophorone, propylene carbonate, γ-butyrolactone, and methyl amyl ketone (2-heptanone). Of these, methyl amyl ketone (2-heptanone) is preferred as a ketone solvent.

Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, methoxyethyl acetate, ethoxyethyl acetate, propylene glycol monomethyl ether acetate (PGMEA), ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, Pyrene glycol monopropyl ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, milk Examples of the ester-based solvent include ethyl acetate, butyl lactate, propyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, and propyl 3-methoxypropionate. Among these, butyl acetate or PGMEA is preferred as the ester-based solvent.

Examples of nitrile solvents include acetonitrile, propionitrile, valeronitrile, butyronitrile, etc.

The organic developer may contain known additives as necessary. Examples of such additives include surfactants. The surfactants are not particularly limited, but may include, for example, ionic or nonionic fluorine-based and/or silicon-based surfactants.
The surfactant is preferably a non-ionic surfactant, and more preferably a non-ionic fluorine-based surfactant or a non-ionic silicon-based surfactant.
When a surfactant is added, the amount of the surfactant added is usually from 0.001 to 5% by mass, preferably from 0.005 to 2% by mass, and more preferably from 0.01 to 0.5% by mass, based on the total amount of the organic developer.

The development process can be carried out by a known development method, such as a method of immersing the support in a developer for a certain period of time (dip method), a method of piling up the developer on the support surface by surface tension and leaving it still for a certain period of time (paddle method), a method of spraying the developer on the support surface (spray method), or a method of continuously applying developer while scanning a developer application nozzle at a constant speed onto a support rotating at a constant speed (dynamic dispense method).

The rinse treatment (cleaning treatment) using a rinse liquid can be carried out by a known rinse method, such as a method of continuously applying the rinse liquid onto a support rotating at a constant speed (spin coating method), a method of immersing the support in the rinse liquid for a certain period of time (dip method), or a method of spraying the rinse liquid onto the surface of the support (spray method).
The rinsing treatment is preferably carried out using a rinsing liquid containing an organic solvent.

By the above-mentioned film forming step, exposure step, and development step, a substrate having a recess on its surface (a structure having a pattern formed on a substrate, a stepped substrate) can be manufactured.
The thickness (horizontal dimension relative to the support) and height (vertical dimension relative to the support) of the side walls can be set appropriately based on the size of the hollow portion, which is determined according to the type of electronic device to be accommodated in the recess.

<About photosensitive resist film>
The photosensitive resist film in this embodiment has a negative photosensitive resin film containing an epoxy group-containing resin (A) (hereinafter referred to as “component (A)”) and a photoinitiator (I) (hereinafter referred to as “component (I)”) that generates an acid upon exposure to light.
The components constituting the photosensitive resist film will be described in detail below.

When a photosensitive resin film is formed using such a photosensitive resist film and selectively exposed to light, in the exposed portion of the photosensitive resin film, an acid is generated from component (I), and the epoxy groups in component (A) undergo ring-opening polymerization due to the action of the acid, reducing the solubility of component (A) in a developer containing an organic solvent. On the other hand, in the unexposed portion of the photosensitive resin film, the solubility of component (A) in a developer containing an organic solvent does not change, so that a difference in solubility in a developer containing an organic solvent occurs between the exposed and unexposed portions of the photosensitive resin film. In other words, the photosensitive resin film is negative type. Therefore, when the photosensitive resin film is developed with a developer containing an organic solvent, the unexposed portion is dissolved and removed, forming a negative type pattern.

Here, the negative photosensitive resin film of the photosensitive resist film is typically made of a B-stage (semi-cured) resin material.
The photosensitive resist film may be a laminate film in which a photosensitive resin film is laminated on a substrate film.

Such a photosensitive resist film can be produced by applying a negative photosensitive resin composition in which the components (A) and (I) are dissolved in a solvent onto a substrate film, and then drying the composition to form a photosensitive resin film.
The negative photosensitive resin composition may be applied onto the substrate film by a suitable method using an applicator, a blade coater, a lip coater, a comma coater, a film coater or the like.
The thickness of the photosensitive resin film is preferably 100 μm or less, and more preferably 5 to 50 μm.

Any known material can be used for the base film, such as a thermoplastic resin film. Examples of such thermoplastic resins include polyesters such as polyethylene terephthalate. The thickness of the base film is preferably 2 to 150 μm.

In the method for producing a hollow structural member according to this embodiment, steps (i) to (v) are carried out using the substrate having a recess on its surface, which is prepared in the above step (0), and the photosensitive resist film.
As a method for manufacturing a hollow structural body, for example, a first embodiment and a second embodiment shown below can be given.

Each embodiment of the method for manufacturing a hollow structure will be described below with reference to the drawings.

First Embodiment
In step (0), a photosensitive resist film is prepared which is a laminate film in which a photosensitive resin film is laminated on a substrate film, and steps (i), (ii), (iii), (iv), and (v) are carried out in this order.
In addition, the heat treatment in the step (v) is performed by heating at a temperature of 150° C. or less for 10 minutes or more, and then further heating at a temperature exceeding 150° C. as an operation (x).

FIG. 1 is a schematic diagram illustrating a method for manufacturing a hollow structure according to the first embodiment.
1, a substrate having a recess 15 on its surface is formed by a substrate 10 and a sidewall 20 formed on the substrate 10. The photosensitive resist film used is a laminated film 80 in which a photosensitive resin film 30 is laminated on a base film 50.
In this embodiment, the side wall 20 is made of a photosensitive resin material. The photosensitive resin material forming the side wall 20 may be the same material as the photosensitive resin film forming the top plate portion, or may be a different material.

[Step (i)]
In the step (i), the laminated film 80 is disposed so that the surface of the photosensitive resin film 30 of the photosensitive resist film (laminated film 80 ) covers the opening surface of the recess 15 in the substrate 10 .
1, the laminated film 80 is disposed so as to face the substrate 10 via the side wall 20. A hollow sealed space is formed surrounded by the substrate 10, the side wall 20, and the photosensitive resin film 30.

[Step (D)]
In step (D), after step (i), the base film 50 is peeled off from the photosensitive resin film 30 in the laminate film 80 .

[Step (ii)]
In the step (ii), the photosensitive resin film 30 is exposed to light.
For example, the photosensitive resin film 30 is selectively exposed to light using a known exposure device through a photomask 60 on which a predetermined pattern is formed.

There are no particular limitations on the wavelength used for exposure, and radiation, for example, ultraviolet light with a wavelength of 300 to 500 nm, i-line (wavelength 365 nm), or visible light, is selectively irradiated (exposed). Sources of these radiations include low-pressure mercury lamps, high-pressure mercury lamps, extra-high-pressure mercury lamps, metal halide lamps, argon gas lasers, etc.

[Step (iii)]
In the step (iii), the exposed photosensitive resin film 30 is subjected to a heat treatment, a so-called post-exposure bake (PEB) treatment.
The PEB treatment is carried out, for example, at a temperature of 80 to 150° C. for 40 to 600 seconds, preferably 60 to 300 seconds.
By the heat treatment in the step (iii), the photosensitive resin film 30 after exposure is divided into exposed portions 30A where the epoxy groups in the component (A) have undergone ring-opening polymerization, and unexposed portions 30B which remain unchanged.

[Step (iv)]
In the step (iv), the photosensitive resin film 30 after the PEB treatment is developed to form a negative pattern.
The development here can be carried out in the same manner as in the development step in the above-mentioned [Step (0)]. After the development, a rinsing treatment is preferably carried out.
By the development in the step (iv), the unexposed portion 30B is dissolved and removed, and the exposed portion 30A which becomes the top plate portion remains as a negative pattern.

[Step (v)]
In step (v), the developed negative pattern (exposed portion 30A) is further hardened by a heat treatment (curing operation) to obtain a hollow structural body 100 whose top plate portion is made of a hardened body 40 of the photosensitive resin film 30. In Fig. 1, the hardened body 40 is formed by hardening the photosensitive resin material forming the side wall 20 and the photosensitive resin film 30, and is integrated with them.
The heat treatment in step (v) is carried out by an operation (x) of heating at a temperature of 150° C. or less for 10 minutes or more (first heating) and then further heating at a temperature exceeding 150° C. (second heating).

Regarding operation (x):
The operation (x) is an operation of performing a first heating step and then a second heating step.

The first heating refers to heating at a temperature of 150° C. or less for 10 minutes or more.
The temperature and duration of the first heating are preferably 50° C. or higher and 150° C. or lower, more preferably 50° C. or higher and 125° C. or lower, and are preferably 30 minutes or higher and 120 minutes or lower, more preferably 60 minutes or higher and 90 minutes or lower.
The heating operation in the first heating may be performed in one step or in two or more steps. For example, when the first heating is performed in two steps, the heating operation in the first heating is preferably performed by heating at a temperature of 50° C. to 90° C. for 30 minutes to 90 minutes, and then further heating at a temperature higher than 90° C. to 150° C. for 10 minutes to 60 minutes.

The second heating refers to heating at a temperature above 150°C.
The temperature and duration of the second heating are preferably higher than 150° C. and not more than 250° C., more preferably 160° C. or higher and not more than 220° C., and are preferably 30 minutes or longer and 120 minutes or shorter, more preferably 60 minutes or longer and not more than 90 minutes.
The heating operation in the second heating may be performed in one step or in two or more steps. For example, when the second heating is performed in two steps, the heating operation in the second heating is preferably performed by heating at a temperature higher than 150° C. and lower than 180° C. for 10 minutes to 60 minutes, and then further heating at a temperature higher than 180° C. and lower than 220° C. for 30 minutes to 90 minutes.

In the manufacturing method for a hollow structure according to the first embodiment, it is preferable to carry out the above-mentioned operation (x) of heating at a temperature of 50°C or higher and 125°C or lower for 10 minutes or more, and then further heating at a temperature of 160°C or higher for 30 minutes or more, since this inhibits deformation of the top plate portion and makes it easier to increase strength.
In addition, in the above-mentioned operation (x), it is preferable that the first heating is performed in two or more steps, and furthermore, the second heating is performed in two or more steps.Furthermore, from the viewpoint of productivity (time cycle, etc.), it is more preferable that the above-mentioned operation (x) is performed in two steps, and furthermore, the second heating is also performed in two steps.

In the manufacturing method for hollow structural members according to the first embodiment described above, the heat treatment (curing operation) in step (v) is carried out by heating at a temperature of 150° C. or less for 10 minutes or more, and then further heating at a temperature exceeding 150° C. as an operation (x).
In this way, by heating the developed negative pattern (exposed portion 30A) while increasing the temperature from lower to higher than 150° C., the expansion of air inside the hollow during the curing operation is suppressed more than in the past, and the hardening can be sufficiently advanced while reducing the internal pressure. Therefore, according to the first embodiment, deformation of the top plate due to the curing operation is suppressed, and a hollow structure with increased strength can be stably manufactured.

Second Embodiment
In step (0), a photosensitive resist film is prepared which is a laminate film in which a photosensitive resin film is laminated on a substrate film, and steps (i), (ii), (iii), (iv), and (v') are carried out in this order.
In addition, the heat treatment in the step (v') is carried out by an operation (y) of heating at a temperature of 100°C or higher after irradiation with ultraviolet rays.

The explanation of steps (i), (ii), (iii), and (iv) in the second embodiment is the same as the explanation of steps (i), (ii), (iii), and (iv) in the first embodiment described above.

[Step (v')]
In the step (v'), the developed negative pattern (exposed area) is further subjected to a heat treatment (curing operation) to harden it, thereby obtaining a hollow structure whose top plate is made of a hardened photosensitive resin film.
The heat treatment in step (v') is carried out by an operation (y) of irradiating with ultraviolet light and then heating at a temperature of 100°C or higher.

Regarding operation (y):
The operation (y) is an operation of performing heating after irradiating with ultraviolet light.
The ultraviolet irradiation is preferably carried out at an irradiation dose of, for example, 1000 to 10000 mJ/cm ² .
The heating in the step (y) refers to heating at a temperature of 100° C. or higher.
The heating temperature and duration in the step (y) are preferably 100° C. or higher and 200° C. or lower, more preferably 150° C. or higher and 180° C. or lower, and are preferably 15 minutes or higher and 120 minutes or lower, more preferably 30 minutes or higher and 90 minutes or lower.
The heating operation in the step (y) may be carried out in one step or in two or more steps.

In the manufacturing method for a hollow structural member according to the second embodiment, as the above-mentioned operation (y), it is preferable to perform an operation of irradiating the top plate with ultraviolet light at 1,000 to 10,000 mJ/ ^cm2 and then heating at a temperature of 160°C or higher for 30 minutes or longer, since this operation can suppress deformation of the top plate and can easily increase the strength.

In the manufacturing method for a hollow structural body according to the second embodiment described above, the heat treatment (curing operation) in step (v) is carried out by irradiating with ultraviolet rays and then performing an operation (y) of heating at a temperature of 100° C. or higher.
In this way, by irradiating the developed negative pattern (exposed portion) with ultraviolet light and then heating it, the heating temperature for the curing operation can be set to a lower temperature. This makes it possible to suppress the expansion of air inside the hollow more than before, thereby reducing the internal pressure. In addition, it is possible to sufficiently progress the curing of the developed negative pattern (exposed portion). Therefore, according to the second embodiment, deformation of the top plate portion due to the curing operation is suppressed, and a hollow structure with increased strength can be stably manufactured.

<Other embodiments>
Regarding the manufacturing method for a hollow structure according to the embodiment described above, a case has been described in which a photosensitive resist film is prepared as a laminate film in which a photosensitive resin film is laminated on a base film. However, this is not limited to this, and it is also possible to prepare, for example, a single layer of photosensitive resin film, or a laminate in which a photosensitive resin film and a cover film are laminated in this order on a base film.

The cover film may be a known one, such as a polyethylene film, a polypropylene film, etc. The cover film is preferably a film having a smaller adhesive strength with the photosensitive resin film than the base film.
The thickness of the cover film is preferably 2 to 150 μm, more preferably 2 to 100 μm, and further preferably 5 to 50 μm.
The base film and the cover film may be made of the same film material or different film materials.
When in use, for example, the cover film can be peeled off and the resulting laminate film of photosensitive resin film/substrate film can be used.

In addition, in the manufacturing method of the hollow structure according to the embodiment described above, the peeling operation of the base film constituting the photosensitive resist film is performed between the steps (i) and (ii), but this is not limited thereto, and the peeling operation may be performed between the steps (ii) and (iii), or between the steps (iii) and (iv).

<Ingredients that make up photosensitive resist film>
The photosensitive resist film in this embodiment has a negative photosensitive resin film containing an epoxy group-containing resin (A) and a photoinitiator (I) that generates an acid upon exposure to light.

Epoxy group-containing resin (A):
The epoxy group-containing resin (component (A)) is not particularly limited as long as it has a sufficient number of epoxy groups in one molecule to form a pattern by exposure.
Examples of the component (A) include novolac type epoxy resins (Anv), bisphenol A type epoxy resins (Abp), bisphenol F type epoxy resins, aliphatic epoxy resins, and acrylic resins (Aac).

..Novolac type epoxy resin (Anv)
Suitable examples of the novolac epoxy resin (Anv) include resin (A1) (hereinafter also referred to as “component (A1)”) represented by the following general formula (A1).

［式中、Ｒ^ｐ１及びＲ^ｐ２は、それぞれ独立に、水素原子又は炭素数１～５のアルキル基である。複数のＲ^ｐ１は、互いに同一であってもよく異なっていてもよい。複数のＲ^ｐ２は、互いに同一であってもよく異なっていてもよい。ｎ_１は、１～５の整数である。Ｒ^ＥＰは、エポキシ基含有基である。複数のＲ^ＥＰは、互いに同一であってもよく異なっていてもよい。］

[In the formula, R ^p1 and R ^p2 are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Multiple R ^p1s may be the same as or different from each other. Multiple R ^p2s may be the same as or different from each other. _n1 is an integer of 1 to 5. R ^EP is an epoxy group-containing group. Multiple R ^EPs may be the same as or different from each other.]

In the formula (A1), the alkyl group having 1 to 5 carbon atoms for R ^p1 and R ^p2 is, for example, a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms. Examples of the linear or branched alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group, and examples of the cyclic alkyl group include a cyclobutyl group, and a cyclopentyl group.
Among these, R ^p1 and R ^p2 are preferably a hydrogen atom or a linear or branched alkyl group, more preferably a hydrogen atom or a linear alkyl group, and particularly preferably a hydrogen atom or a methyl group.
In formula (A1), multiple R ^p1 may be the same as or different from each other, and multiple R ^p2 may be the same as or different from each other.

In formula (A1), _n1 is an integer of 1 to 5, preferably 2 or 3, and more preferably 2.

In formula (A1), R ^EP is an epoxy group-containing group.
The epoxy group-containing group of ^REP is not particularly limited, and examples thereof include a group consisting of only epoxy groups; a group consisting of only alicyclic epoxy groups; and a group having an epoxy group or alicyclic epoxy group and a divalent linking group.
The alicyclic epoxy group is an alicyclic group having an oxacyclopropane structure which is a three-membered ring ether, and specifically, is a group having an alicyclic group and an oxacyclopropane structure.
The alicyclic group that is the basic skeleton of the alicyclic epoxy group may be monocyclic or polycyclic. Examples of the monocyclic alicyclic group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. Examples of the polycyclic alicyclic group include a norbornyl group, an isobornyl group, a tricyclononyl group, a tricyclodecyl group, and a tetracyclododecyl group. The hydrogen atom of these alicyclic groups may be substituted with an alkyl group, an alkoxy group, a hydroxyl group, or the like.
In the case of a group having an epoxy group or an alicyclic epoxy group and a divalent linking group, it is preferable that the epoxy group or the alicyclic epoxy group is linked via the divalent linking group bonded to an oxygen atom (—O—) in the formula.

Here, the divalent linking group is not particularly limited, but preferred examples include a divalent hydrocarbon group which may have a substituent, and a divalent linking group containing a heteroatom.

Regarding the divalent hydrocarbon group which may have a substituent:
Such a divalent hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group.
The aliphatic hydrocarbon group in the divalent hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.
More specifically, the aliphatic hydrocarbon group may be a straight-chain or branched-chain aliphatic hydrocarbon group, or an aliphatic hydrocarbon group containing a ring in the structure.

The linear aliphatic hydrocarbon group preferably has a carbon number of 1 to 10, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1 to 3. As the linear aliphatic hydrocarbon group, a linear alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [-(CH ₂ ) ₃ -], a tetramethylene group [-(CH ₂ ) ₄ -], a pentamethylene group [-(CH ₂ ) ₅ -], and the like.
The branched aliphatic hydrocarbon group preferably has 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms, even more preferably 2 to 4 carbon atoms, and most preferably 2 or 3 carbon atoms. As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples thereof include alkylmethylene groups such as -CH( _CH3 )-, -CH( _CH2CH3 )-, -C( _CH3 ) _2- , -C _{(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2- ; alkylethylene groups such as -CH ( CH3 ) CH2- ,} -CH( _{CH3 )} CH( _CH3 )-, -C _{( CH3} ) _{2CH2- ,} -CH( _{CH2CH3 ) CH2- , and -C} ( _CH2CH3 ) _{2 - CH2-} ; alkyltrimethylene groups such as -CH( _CH3 ) _CH2CH2CH2- , _-CH2CH ( _CH3 ) _CH2CH2- , etc.; and alkylalkylene groups such as alkyltetramethylene groups such as -CH( _CH3 ) _{CH2CH2CH2- , -CH2CH} (CH3) _CH2CH2- , etc. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

Examples of the aliphatic hydrocarbon group containing a ring in the structure include alicyclic hydrocarbon groups (groups in which two hydrogen atoms have been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a linear or branched aliphatic hydrocarbon group, groups in which an alicyclic hydrocarbon group is present in the middle of a linear or branched aliphatic hydrocarbon group, etc. Examples of the linear or branched aliphatic hydrocarbon group include the same as those described above.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.
The polycyclic alicyclic hydrocarbon group is preferably a group in which two hydrogen atoms have been removed from a polycycloalkane, and the polycycloalkane preferably has 7 to 12 carbon atoms, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

The aromatic hydrocarbon group in the divalent hydrocarbon group is a hydrocarbon group having at least one aromatic ring. The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having (4n+2) π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a heteroatom. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specific examples of the aromatic hydrocarbon group include a group in which two hydrogen atoms have been removed from the aromatic hydrocarbon ring or aromatic heterocycle (arylene group or heteroarylene group); a group in which two hydrogen atoms have been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); a group in which one hydrogen atom of a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group) has been substituted with an alkylene group (e.g., a group in which one hydrogen atom has been further removed from the aryl group in an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group). The number of carbon atoms in the alkylene group bonded to the aryl group or heteroaryl group is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The divalent hydrocarbon group may have a substituent.
The linear or branched aliphatic hydrocarbon group as the divalent hydrocarbon group may or may not have a substituent, which may include a fluorine atom, a fluorinated alkyl group having 1 to 5 carbon atoms and substituted with a fluorine atom, and a carbonyl group.

The alicyclic hydrocarbon group in the aliphatic hydrocarbon group containing a ring in the structure as the divalent hydrocarbon group may or may not have a substituent, such as an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, or a carbonyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
The alkoxy group as the substituent is preferably an alkoxy group having 1 to 5 carbon atoms, more preferably a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a tert-butoxy group, and most preferably a methoxy group or an ethoxy group.
Examples of the halogen atom as the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, with a fluorine atom being preferred.
Examples of the halogenated alkyl group as the substituent include the alkyl groups in which some or all of the hydrogen atoms of the alkyl groups are substituted with the halogen atoms.
In the alicyclic hydrocarbon group, some of the carbon atoms constituting the ring structure may be substituted with a substituent containing a hetero atom. Preferred examples of the substituent containing a hetero atom include -O-, -C(=O)-O-, -S-, -S(=O) ₂ - and -S(=O) ₂ -O-.

In the aromatic hydrocarbon group as a divalent hydrocarbon group, a hydrogen atom of the aromatic hydrocarbon group may be substituted with a substituent. For example, a hydrogen atom bonded to an aromatic ring in the aromatic hydrocarbon group may be substituted with a substituent. Examples of the substituent include an alkyl group, an alkoxy group, a halogen atom, a halogenated alkyl group, and a hydroxyl group.
The alkyl group as the substituent is preferably an alkyl group having 1 to 5 carbon atoms, and most preferably a methyl group, an ethyl group, a propyl group, an n-butyl group, or a tert-butyl group.
Examples of the alkoxy group, halogen atom and halogenated alkyl group as the substituent include those exemplified as the substituent substituting a hydrogen atom of the alicyclic hydrocarbon group.

Regarding divalent linking groups containing heteroatoms:
The heteroatom in the divalent linking group containing a heteroatom is an atom other than a carbon atom or a hydrogen atom, and examples thereof include an oxygen atom, a nitrogen atom, a sulfur atom, and a halogen atom.

In the divalent linking group containing a hetero atom, preferred examples of the linking group include -O-, -C(=O)-O-, -C(=O)-, -O-C(=O)-O-; -C(=O)-NH-, -NH-, -NH-C(=O)-O-, -NH-C(=NH)- (H may be substituted with a substituent such as an alkyl group or an acyl group); -S-, -S(=O) ₂ -, -S(=O) ₂ -O-, the general formula -Y ²¹ -O-Y ²² -, -Y ²¹ -O-, -Y ²¹ -C(=O)-O-, -C(=O)-O-Y ²¹ , -[Y ²¹ -C(=O)-O] _{m "} -Y ²² -, or -Y ²¹ -O-C(=O)-Y ²² - (wherein Y ²¹ and Y ²² each independently represent a divalent hydrocarbon group which may have a substituent, O represents an oxygen atom, and m″ represents an integer of 0 to 3).
When the divalent linking group containing a hetero atom is -C(=O)-NH-, -NH-, -NH-C(=O)-O-, or -NH-C(=NH)-, the H may be substituted with a substituent such as an alkyl group, acyl, etc. The substituent (alkyl group, acyl group, etc.) preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 5 carbon atoms.
In the formula -Y ²¹ -O-Y ²² -, -Y ²¹ -O-, -Y ²¹ -C(═O)-O-, -C(═O)-O-Y ²¹ -, -[Y ²¹ -C(═O)-O] _m" -Y ²² - or -Y ²¹ -O-C(═O)-Y ²² -, Y ²¹ and Y ²² each independently represent a divalent hydrocarbon group which may have a substituent. Examples of the divalent hydrocarbon group include the same as the "divalent hydrocarbon group which may have a substituent" listed in the description of the divalent linking group above.
Y ²¹ is preferably a linear aliphatic hydrocarbon group, more preferably a linear alkylene group, still more preferably a linear alkylene group having 1 to 5 carbon atoms, and particularly preferably a methylene group or ethylene group.
Y ²² is preferably a linear or branched aliphatic hydrocarbon group, more preferably a methylene group, an ethylene group or an alkylmethylene group. The alkyl group in the alkylmethylene group is preferably a linear alkyl group having 1 to 5 carbon atoms, more preferably a linear alkyl group having 1 to 3 carbon atoms, and most preferably a methyl group.
In the group represented by the formula -[Y ²¹ -C(═O)-O] _m" -Y ²² -, m" is an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 1. That is, as the group represented by the formula -[Y ²¹ -C(═O)-O] _m" -Y ²² -, a group represented by the formula -Y ²¹ -C(═O)-O-Y ²² - is particularly preferred. Of these, a group represented by the formula -(CH ₂ ) _a' -C(═O)-O-(CH ₂ ) _b' - is preferred. In the formula, a' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, even more preferably 1 or 2, and most preferably 1. b' is an integer of 1 to 10, preferably an integer of 1 to 8, more preferably an integer of 1 to 5, even more preferably 1 or 2, and most preferably 1.

Of these, the epoxy group-containing group in ^REP is preferably a glycidyl group.

Preferable examples of novolac-type epoxy resins (Anv) include resins having a structural unit represented by the following general formula (anv1):

［式中、Ｒ^ＥＰは、エポキシ基含有基であり、Ｒ^ａ２２、Ｒ^ａ２３は、それぞれ独立に水素原子、炭素数１～５のアルキル基又はハロゲン原子である。］

[In the formula, R ^EP is an epoxy group-containing group, and R ^a22 and R ^a23 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogen atom.]

In formula (anv1), the alkyl group having 1 to 5 carbon atoms for R ^a22 and R ^a23 is the same as the alkyl group having 1 to 5 carbon atoms for R ^p1 and R ^p2 in formula (A1). The halogen atom for R ^a22 and R ^a23 is preferably a chlorine atom or a bromine atom.
In formula (anv1), ^REP is the same as ^REP in formula (A1) above, and is preferably a glycidyl group.

Specific examples of structural units represented by the formula (anv1) are shown below.

The novolac epoxy resin (Anv) may be a resin consisting of only the structural unit (anv1), or may be a resin having the structural unit (anv1) and other structural units. Examples of these other structural units include the structural units represented by the following general formulas (anv2) to (anv3).

［式中、Ｒ^ａ２４は、置換基を有していてもよい炭化水素基である。Ｒ^ａ２５～Ｒ^ａ２６、Ｒ^ａ２８～Ｒ^ａ３０は、それぞれ独立に水素原子、炭素数１～５のアルキル基又はハロゲン原子である。Ｒ^ａ２７は、エポキシ基含有基又は置換基を有していてもよい炭化水素基である。］

[In the formula, R ^a24 is a hydrocarbon group which may have a substituent. R ^a25 to R ^a26 and R ^a28 to R ^a30 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogen atom. R ^a27 is an epoxy group-containing group or a hydrocarbon group which may have a substituent.]

In formula (anv2), R ^a24 represents a hydrocarbon group which may have a substituent. Examples of the hydrocarbon group which may have a substituent include a linear or branched alkyl group, and a cyclic hydrocarbon group.
The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Among these, a methyl group, an ethyl group, or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable.

The branched alkyl group preferably has 3 to 10 carbon atoms, more preferably 3 to 5. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group, a 1,1-diethylpropyl group, and a 2,2-dimethylbutyl group, with an isopropyl group being preferred.

When R ^a24 is a cyclic hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be a polycyclic group or a monocyclic group.
The monocyclic aliphatic hydrocarbon group is preferably a group in which one hydrogen atom has been removed from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane.
As the aliphatic hydrocarbon group that is a polycyclic group, a group in which one hydrogen atom has been removed from a polycycloalkane is preferable, and the polycycloalkane is preferably one having 7 to 12 carbon atoms, and specific examples thereof include adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

When the cyclic hydrocarbon group of R ^a24 is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring.
The aromatic ring is not particularly limited as long as it is a cyclic conjugated system having 4n+2 π electrons, and may be monocyclic or polycyclic. The number of carbon atoms in the aromatic ring is preferably 5 to 30, more preferably 5 to 20, even more preferably 6 to 15, and particularly preferably 6 to 12. Specific examples of the aromatic ring include aromatic hydrocarbon rings such as benzene, naphthalene, anthracene, and phenanthrene; and aromatic heterocycles in which a part of the carbon atoms constituting the aromatic hydrocarbon ring is substituted with a heteroatom. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the aromatic heterocycle include a pyridine ring and a thiophene ring.
Specific examples of the aromatic hydrocarbon group in R ^a24 include a group in which one hydrogen atom has been removed from the aromatic hydrocarbon ring or aromatic heterocycle (aryl group or heteroaryl group); a group in which one hydrogen atom has been removed from an aromatic compound containing two or more aromatic rings (e.g., biphenyl, fluorene, etc.); a group in which one hydrogen atom of the aromatic hydrocarbon ring or aromatic heterocycle has been substituted with an alkylene group (e.g., arylalkyl groups such as benzyl group, phenethyl group, 1-naphthylmethyl group, 2-naphthylmethyl group, 1-naphthylethyl group, and 2-naphthylethyl group), etc. The number of carbon atoms in the alkylene group bonded to the aromatic hydrocarbon ring or aromatic heterocycle is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

In formulae (anv2) and (anv3), R ^a25 to R ^a26 and R ^a28 to R ^a30 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogen atom, and the alkyl group having 1 to 5 carbon atoms and the halogen atom are the same as defined above for R ^a22 and R ^a23 , respectively.

In formula (anv3), R ^a27 represents an epoxy group-containing group or a hydrocarbon group which may have a substituent. The epoxy group-containing group of R ^a27 is the same as R ^EP in formula (A1), and the hydrocarbon group which may have a substituent of R ^a27 is the same as R ^a24 .

Specific examples of the structural units represented by the formulas (anv2) to (anv3) are shown below.

When the novolac epoxy resin (Anv) has other structural units in addition to the structural unit (anv1), the proportion of each structural unit in the resin (Anv) is not particularly limited, but the total of structural units having epoxy groups is preferably 10 to 90 mol%, more preferably 20 to 80 mol%, and even more preferably 30 to 70 mol%, relative to the total of all structural units constituting the resin (Anv).

Bisphenol A epoxy resin (Abp)
The bisphenol A type epoxy resin (Abp) includes an epoxy resin having a structure represented by the following general formula (abp1).

［式中、Ｒ^ＥＰは、エポキシ基含有基であり、Ｒ^ａ３１、Ｒ^ａ３２はそれぞれ独立に、水素原子又は炭素数１～５のアルキル基であり、ｎａ^３１は１～５０の整数である。］

[In the formula, R ^EP is an epoxy group-containing group, R ^a31 and R ^a32 each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and na ³¹ is an integer of 1 to 50.]

In formula (abp1), the alkyl group having 1 to 5 carbon atoms for R ^a31 and R ^a32 is the same as the alkyl group having 1 to 5 carbon atoms for R ^p1 and R ^p2 in formula (A1). Of these, R ^a31 and R ^a32 are preferably a hydrogen atom or a methyl group.
^REP is the same as ^REP in the above formula (A1), and is preferably a glycidyl group.

Aliphatic epoxy resin, acrylic resin (Aac)
Examples of the aliphatic epoxy resin and acrylic resin (Aac) include resins having epoxy group-containing units represented by the following general formulas (a1-1) and (a1-2), respectively.

［式中、Ｒは水素原子、炭素数１～５のアルキル基又は炭素数１～５のハロゲン化アルキル基である。Ｖａ^４１は、置換基を有していてもよい２価の炭化水素基である。ｎａ^４１は０～２の整数である。Ｒ^ａ４１、Ｒ^ａ４２はエポキシ基含有基である。ｎａ^４２は０又は１である。Ｗａ^４１は（ｎａ^４３＋１）価の脂肪族炭化水素基である。ｎａ^４３は１～３の整数である。］

[In the formula, R is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms. Va ⁴¹ is a divalent hydrocarbon group which may have a substituent. na ⁴¹ is an integer from 0 to 2. R ^a41 and R ^a42 are epoxy group-containing groups. na ⁴² is 0 or 1. ^{Wa 41} is an aliphatic hydrocarbon group having a valence of (na ⁴³ +1). na ⁴³ is an integer from 1 to 3.]

In the above formula (a1-1), R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms.
The alkyl group having 1 to 5 carbon atoms represented by R is preferably linear or branched, and specific examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, and a neopentyl group.
The halogenated alkyl group having 1 to 5 carbon atoms for R is a group in which some or all of the hydrogen atoms of the alkyl group having 1 to 5 carbon atoms have been substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom is particularly preferred.
R is preferably a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms, and from the viewpoint of industrial availability, a hydrogen atom or a methyl group is most preferred.

In the formula (a1-1), Va ⁴¹ represents a divalent hydrocarbon group which may have a substituent, and examples of the divalent hydrocarbon group which may have a substituent include the same groups as the divalent hydrocarbon group which may have a substituent described in relation to R ^EP in the formula (A1).
Among the above, the hydrocarbon group of Va ⁴¹ is preferably an aliphatic hydrocarbon group, more preferably a linear or branched aliphatic hydrocarbon group, further preferably a linear aliphatic hydrocarbon group, and particularly preferably a linear alkylene group.

In formula (a1-1), na ⁴¹ represents an integer of 0 to 2, and is preferably 0 or 1.

In formulae (a1-1) and (a1-2), R ^a41 and R ^a42 each represent an epoxy group-containing group and are the same as R ^EP in formula (A1).

In formula (a1-2), the (na ⁴³ +1)-valent aliphatic hydrocarbon group in Wa ⁴¹ means a hydrocarbon group having no aromaticity, and may be either saturated or unsaturated, and is usually preferably saturated. Examples of the aliphatic hydrocarbon group include linear or branched aliphatic hydrocarbon groups, aliphatic hydrocarbon groups containing a ring in their structure, and groups combining linear or branched aliphatic hydrocarbon groups with aliphatic hydrocarbon groups containing a ring in their structure.

In formula (a1-2), na ⁴³ represents an integer of 1 to 3, and is preferably 1 or 2.

Specific examples of structural units represented by formula (a1-1) or (a1-2) are shown below.

In the above formula, R ^α represents a hydrogen atom, a methyl group, or a trifluoromethyl group.
R ^a51 represents a divalent hydrocarbon group having 1 to 8 carbon atoms. R ^a52 represents a divalent hydrocarbon group having 1 to 20 carbon atoms. R ^a53 represents a hydrogen atom or a methyl group. na ⁵¹ is an integer of 0 to 10.
R ^a51 , R ^a52 and R ^a53 may be the same or different.

Furthermore, the acrylic resin (Aac) may have a structural unit derived from another polymerizable compound for the purpose of appropriately controlling the physical and chemical properties. Examples of such polymerizable compounds include known radical polymerizable compounds and anion polymerizable compounds. Examples of such polymerizable compounds include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; methacrylic acid derivatives having a carboxyl group and an ester bond such as 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl maleic acid, 2-methacryloyloxyethyl phthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid; (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate; (meth)acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate; phenyl (meth)acrylate, ... (Meth)acrylic acid aryl esters such as diethyl maleate and dibutyl fumarate; dicarboxylic acid diesters such as diethyl maleate and dibutyl fumarate; vinyl group-containing aromatic compounds such as styrene, α-methylstyrene, chlorostyrene, chloromethylstyrene, vinyltoluene, hydroxystyrene, α-methylhydroxystyrene, and α-ethylhydroxystyrene; vinyl group-containing aliphatic compounds such as vinyl acetate; conjugated diolefins such as butadiene and isoprene; nitrile group-containing polymerizable compounds such as acrylonitrile and methacrylonitrile; chlorine-containing polymerizable compounds such as vinyl chloride and vinylidene chloride; amide bond-containing polymerizable compounds such as acrylamide and methacrylamide; and the like.

When the aliphatic epoxy resin or acrylic resin (Aac) contains other structural units, the content of epoxy group-containing units in the resin is preferably 5 to 40 mol%, more preferably 10 to 30 mol%, and most preferably 15 to 25 mol%.

Furthermore, preferred examples of aliphatic epoxy resins include compounds containing a partial structure represented by the following general formula (m1) (hereinafter also referred to as "component (m1)").

［式中、ｎ_２は、１～４の整数である。＊は結合手を示す。］

[In the formula, _n2 is an integer of 1 to 4. * indicates a bond.]

In formula (m1), _n2 is an integer of 1 to 4, preferably an integer of 1 to 3, and more preferably 2.

Examples of the (m1) component include compounds in which a plurality of partial structures represented by the above general formula (m1) are bonded via a divalent linking group or a single bond. Among these, compounds in which a plurality of partial structures represented by the above general formula (m1) are bonded via a divalent linking group are preferred.
The divalent linking group here is not particularly limited, but suitable examples include divalent hydrocarbon groups which may have a substituent and divalent linking groups containing a heteroatom. The divalent hydrocarbon groups which may have a substituent and divalent linking groups containing a heteroatom are the same as the divalent hydrocarbon groups which may have a substituent and divalent linking groups containing a heteroatom explained in R ^EP (epoxy group-containing group) in the above formula (A1), and among these, divalent linking groups containing a heteroatom are preferred, and a group represented by -Y ²¹ -C(═O)-O- and a group represented by -C(═O)-O-Y ²¹ - are more preferred. As Y ²¹ , a linear aliphatic hydrocarbon group is preferred, a linear alkylene group is more preferred, a linear alkylene group having 1 to 5 carbon atoms is even more preferred, and a methylene group or an ethylene group is particularly preferred.

Furthermore, the aliphatic epoxy resin preferably includes a compound represented by the following general formula (m2) (hereinafter also referred to as "component (m2)").

［式中、Ｒ^ＥＰは、エポキシ基含有基である。複数のＲ^ＥＰは、互いに同一であってもよく異なっていてもよい。］

[In the formula, ^REP is an epoxy group-containing group. A plurality of ^REPs may be the same or different.]

In formula (m2), ^REP is an epoxy group-containing group and is the same as ^REP in formula (A1).

As the component (A), one type may be used alone, or two or more types may be used in combination.
The component (A) preferably contains at least one resin selected from the group consisting of novolac epoxy resins (Anv), bisphenol A epoxy resins (Abp), bisphenol F epoxy resins, aliphatic epoxy resins, and acrylic resins (Aac).
Among these, it is more preferable that the component (A) contains at least one resin selected from the group consisting of novolac type epoxy resins (Anv), bisphenol A type resins (Abp), aliphatic epoxy resins, and acrylic resins (Aac).
Among these, it is more preferable that the component (A) contains at least one resin selected from the group consisting of novolac epoxy resins (Anv), aliphatic epoxy resins, and acrylic resins (Aac), and it is particularly preferable that the component (A) contains at least a novolac epoxy resin (Anv). Among the novolac epoxy resins (Anv), it is preferable to use the component (A1).
Furthermore, it is particularly preferable that the component (A) contains two or more resins selected from the group consisting of novolac epoxy resins (Anv), aliphatic epoxy resins, and acrylic resins (Aac).

When two or more types of resins are used in combination as the component (A), it is preferable that the component (A) includes a combination of a novolac epoxy resin (Anv) and an aliphatic epoxy resin, from the viewpoint of improving the film properties (such as lamination properties) and strength when formed into a photosensitive resist film.
Specific examples of such combinations include a combination of the (A1) component with at least one selected from the group consisting of the (m1) component and the (m2) component (hereinafter referred to as "the (m) component"). Among these, the combination of the (A1) component, the (m1) component and the (m2) component is the most preferred.

When the (m1) component and the (m2) component are both present, the ratio of the (m1) component to the (m2) component, expressed as the mass ratio of the (m1) component/the (m2) component, is preferably 2/8 to 8/2, more preferably 3/7 to 7/3, and even more preferably 4/6 to 6/4. If the mass ratio is within the above-mentioned preferred range, the film properties (such as lamination properties) and strength are further improved when the photosensitive resist film is formed.

In particular, the (A) component contains the (A1), (m1) and (m2) components, and the ratio of the total content of the (m1) and (m2) components to the total content of the (A1), (m1) and (m2) components is preferably 15% by mass or more, more preferably 20% by mass or more, even more preferably 25% by mass or more, particularly preferably more than 25% by mass, and most preferably more than 25% by mass and 30% by mass or less, in terms of the balance between the strength and flexibility of the cured film.

The polystyrene-equivalent weight average molecular weight of component (A) is preferably 100 to 300,000, more preferably 200 to 200,000, and even more preferably 300 to 200,000. By setting the weight average molecular weight in this range, peeling from the support is less likely to occur, and the strength of the cured film that is formed is sufficiently increased.

The component (A) preferably has a dispersity of at least 1.05. Such a dispersity leads to improved lithography properties in pattern formation.
The degree of dispersion referred to here means a value obtained by dividing the mass average molecular weight by the number average molecular weight.

Commercially available products of component (A) include, for example, novolac type epoxy resins (Anv), such as JER-152, JER-154, JER-157S70, and JER-157S65 (all manufactured by Mitsubishi Chemical Corporation), EPICLON N-740, EPICLON N-740, EPICLON N-770, EPICLON N-775, EPICLON N-660, EPICLON N-665, EPICLON N-670, EPICLON N-673, EPICLON N-680, EPICLON N-690, EPICLON N-695, and EPICLON N-740. Examples include HP5000 (both manufactured by DIC Corporation) and EOCN-1020 (both manufactured by Nippon Kayaku Co., Ltd.).

Examples of bisphenol A type epoxy resins (Abp) include JER-827, JER-828, JER-834, JER-1001, JER-1002, JER-1003, JER-1055, JER-1007, JER-1009, and JER-1010 (all manufactured by Mitsubishi Chemical Corporation), EPICLON 860, EPICLON 1050, EPICLON 1051, and EPICLON 1055 (all manufactured by DIC Corporation), etc.

Examples of bisphenol F type epoxy resins include JER-806, JER-807, JER-4004, JER-4005, JER-4007, and JER-4010 (all manufactured by Mitsubishi Chemical Corporation), EPICLON 830 and EPICLON 835 (all manufactured by DIC Corporation), LCE-21, and RE-602S (all manufactured by Nippon Kayaku Co., Ltd.), etc.

Examples of aliphatic epoxy resins include ADEKA RESIN EP-4080S, EP-4085S, and EP-4088S (all manufactured by ADEKA Corporation), CELLOXIDE 2021P, CELLOXIDE 2081, CELLOXIDE 2083, CELLOXIDE 2085, CELLOXIDE 8000, CELLOXIDE 8010, EHPE-3150, EPOLEAD PB 3600, and EPOLEAD PB 4700 (all manufactured by Daicel Corporation), DENACOL EX-211L, EX-212L, EX-214L, EX-216L, EX-321L, and EX-850L (all manufactured by Nagase ChemteX Corporation), and TEPIC-VL (manufactured by Nissan Chemical Industries, Ltd.).

The content of component (A) in the photosensitive resin film of the embodiment may be adjusted according to the film thickness of the photosensitive resin film to be formed.

Photoinitiator (I) that generates acid upon exposure to light
The photoinitiator (component (I)) is a compound that generates cations when irradiated with active energy rays such as ultraviolet rays, far ultraviolet rays, excimer laser light such as KrF or ArF, X-rays, electron beams, etc., and the cations can serve as polymerization initiators.

The component (I) in the photosensitive resin film of the present embodiment is not particularly limited, and examples thereof include a compound represented by the following general formula (I1) (hereinafter referred to as "component (I1)"), a compound represented by the following general formula (I2-1) or (I2-2) (hereinafter referred to as "component (I2)"), and a compound represented by the following general formula (I3-1) or (I3-2) (hereinafter referred to as "component (I3)").
Among the above, both of the component (I1) and the component (I2) generate a relatively strong acid upon exposure to light. Therefore, when a pattern is formed using a photosensitive resin composition containing the component (I), sufficient sensitivity can be obtained and a good pattern can be formed.

Component (I1) The component (I1) is a compound represented by the following general formula (I1).

［式中、Ｒ^ｂ０１～Ｒ^ｂ０４は、それぞれ独立に、置換基を有していてもよいアリール基、又はフッ素原子である。ｑは１以上の整数であって、Ｑ^ｑ＋は、それぞれ独立に、ｑ価の有機カチオンである。］

[In the formula, R ^b01 to R ^b04 each independently represent an aryl group which may have a substituent, or a fluorine atom; q is an integer of 1 or greater; and Q ^q+ each independently represents a q-valent organic cation.]

... Anion Moiety In the above formula (I1), R ^b01 to R ^b04 each independently represent an aryl group which may have a substituent, or a fluorine atom.
The aryl group in R ^b01 to R ^b04 preferably has a carbon number of 5 to 30, more preferably 5 to 20, still more preferably 6 to 15, and particularly preferably 6 to 12. Specific examples include a naphthyl group, a phenyl group, and an anthracenyl group, and the phenyl group is preferred because of its easy availability.
The aryl group in R ^b01 to R ^b04 may have a substituent. The substituent is not particularly limited, but is preferably a halogen atom, a hydroxyl group, an alkyl group (preferably a linear or branched alkyl group, preferably having 1 to 5 carbon atoms), or a halogenated alkyl group, more preferably a halogen atom or a halogenated alkyl group having 1 to 5 carbon atoms, and particularly preferably a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms. When the aryl group has a fluorine atom, the polarity of the anion moiety is increased, which is preferable.
Among these, R ^b01 to R ^b04 in formula (I1) are each preferably a fluorinated phenyl group, and particularly preferably a perfluorophenyl group.

Specific preferred examples of the anion portion of the compound represented by formula (I1) include tetrakis(pentafluorophenyl)borate ([B(C ₆ F ₅ ) ₄ ] ⁻ ); tetrakis[(trifluoromethyl)phenyl]borate ([B(C ₆ H ₄ CF ₃ ) ₄ ] ⁻ ); difluorobis(pentafluorophenyl)borate ([(C ₆ F ₅ ) ₂ BF ₂ ] ⁻ ); trifluoro(pentafluorophenyl)borate ([(C ₆ F ₅ )BF ₃ ] ⁻ ); tetrakis(difluorophenyl)borate ([B(C ₆ H ₃ F ₂ ) ₄ ] ⁻ ); and the like.
Among these, tetrakis(pentafluorophenyl)borate ([B(C ₆ F ₅ ) ₄ ] ⁻ ) is particularly preferable.

...Cation Moiety In formula (I1), q is an integer of 1 or more, and each Q ^q+ is independently a q-valent organic cation.
Suitable examples of Q ^q+ include sulfonium cations and iodonium cations, and the organic cations represented by the following general formulas (ca-1) to (ca-5) are particularly preferred.

［式中、Ｒ^２０１～Ｒ^２０７、およびＲ^２１１～Ｒ^２１２は、それぞれ独立に、置換基を有していてもよいアリール基、ヘテロアリール基、アルキル基またはアルケニル基を表す。Ｒ^２０１～Ｒ^２０３、Ｒ^２０６～Ｒ^２０７、Ｒ^２１１～Ｒ^２１２は、相互に結合して、式中のイオウ原子と共に環を形成してもよい。Ｒ^２０８～Ｒ^２０９は、それぞれ独立に、水素原子または炭素数１～５のアルキル基を表す。Ｒ^２１０は、置換基を有していてもよいアリール基、置換基を有していてもよいアルキル基、置換基を有していてもよいアルケニル基、又は置換基を有していてもよい－ＳＯ_２－含有環式基である。Ｌ^２０１は、－Ｃ（＝Ｏ）－または－Ｃ（＝Ｏ）－Ｏ－を表す。Ｙ^２０１は、それぞれ独立に、アリーレン基、アルキレン基またはアルケニレン基を表す。ｘは、１または２である。Ｗ^２０１は、（ｘ＋１）価の連結基を表す。］

[In the formula, R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² each independently represent an aryl group, a heteroaryl group, an alkyl group or an alkenyl group which may have a substituent. R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² may be mutually bonded to form a ring together with the sulfur atom in the formula. R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an -SO ₂ -containing cyclic group which may have a substituent. L ²⁰¹ represents -C(=O)- or -C(=O)-O-. Y ²⁰¹ each independently represent an arylene group, an alkylene group or an alkenylene group. x is 1 or 2. W ²⁰¹ represents a (x+1)-valent linking group.

The aryl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² includes an unsubstituted aryl group having 6 to 20 carbon atoms, and is preferably a phenyl group or a naphthyl group.
The heteroaryl group in R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² includes those in which a part of the carbon atoms constituting the aryl group is substituted with a heteroatom. Examples of the heteroatom include an oxygen atom, a sulfur atom, and a nitrogen atom. Examples of this heteroaryl group include a group in which one hydrogen atom has been removed from 9H-thioxanthene; examples of the substituted heteroaryl group include a group in which one hydrogen atom has been removed from 9H-thioxanthen-9-one.
The alkyl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group for R ²⁰¹ to R ²⁰⁷ and R ²¹¹ to R ²¹² preferably has 2 to 10 carbon atoms.
Examples of the substituent that R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ²¹² may have include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an oxo group (═O), an aryl group, and groups represented by the following formulas (ca-r-1) to (ca-r-10), respectively.

［式中、Ｒ’^２０１は、それぞれ独立に、水素原子、置換基を有していてもよい環式基、置換基を有していてもよい鎖状のアルキル基、又は置換基を有していてもよい鎖状のアルケニル基である。］

[In the formula, ^R'201 each independently represents a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.]

In the above formulas (ca-r-1) to (ca-r-10), ^R'201 each independently represents a hydrogen atom, a cyclic group which may have a substituent, a chain alkyl group which may have a substituent, or a chain alkenyl group which may have a substituent.

Optionally substituted cyclic group:
The cyclic group is preferably a cyclic hydrocarbon group, and the cyclic hydrocarbon group may be an aromatic hydrocarbon group or a cyclic aliphatic hydrocarbon group. The aliphatic hydrocarbon group means a hydrocarbon group that does not have aromaticity. The aliphatic hydrocarbon group may be saturated or unsaturated, and is usually preferably saturated.

The aromatic hydrocarbon group for ^R'201 is a hydrocarbon group having an aromatic ring. The number of carbon atoms in the aromatic hydrocarbon group is preferably 3 to 30, more preferably 5 to 30, even more preferably 5 to 20, particularly preferably 6 to 15, and most preferably 6 to 10. However, this number of carbon atoms does not include the number of carbon atoms in the substituent.
Specific examples of the aromatic ring contained in the aromatic hydrocarbon group in ^R'201 include benzene, fluorene, naphthalene, anthracene, phenanthrene, biphenyl, or aromatic heterocycles in which some of the carbon atoms constituting these aromatic rings are substituted with heteroatoms, or rings in which some of the hydrogen atoms constituting these aromatic rings or aromatic heterocycles are substituted with oxo groups, etc. Examples of the heteroatom in the aromatic heterocycle include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specific examples of the aromatic hydrocarbon group for ^R'201 include a group in which one hydrogen atom has been removed from the aromatic ring (aryl group: for example, a phenyl group, a naphthyl group, an anthracenyl group, etc.), a group in which one hydrogen atom of the aromatic ring has been substituted with an alkylene group (for example, arylalkyl groups such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, a 2-naphthylethyl group, etc.), a group in which one hydrogen atom has been removed from a ring in which some of the hydrogen atoms constituting the aromatic ring have been substituted with an oxo group or the like (for example, anthraquinone, etc.), and a group in which one hydrogen atom has been removed from an aromatic heterocycle (for example, 9H-thioxanthene, 9H-thioxanthen-9-one, etc.). The number of carbon atoms in the alkylene group (the alkyl chain in the arylalkyl group) is preferably 1 to 4, more preferably 1 to 2, and particularly preferably 1.

The cyclic aliphatic hydrocarbon group for ^R'201 includes an aliphatic hydrocarbon group containing a ring in the structure.
Examples of the aliphatic hydrocarbon group containing a ring in its structure include alicyclic hydrocarbon groups (groups in which one hydrogen atom has been removed from an aliphatic hydrocarbon ring), groups in which an alicyclic hydrocarbon group is bonded to the end of a straight-chain or branched-chain aliphatic hydrocarbon group, and groups in which an alicyclic hydrocarbon group is present in the middle of a straight-chain or branched-chain aliphatic hydrocarbon group.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, and more preferably has 3 to 12 carbon atoms.
The alicyclic hydrocarbon group may be a polycyclic group or a monocyclic group. The monocyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a monocycloalkane. The monocycloalkane preferably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. The polycyclic alicyclic hydrocarbon group is preferably a group obtained by removing one or more hydrogen atoms from a polycycloalkane, and the polycycloalkane preferably has 7 to 30 carbon atoms. Among them, the polycycloalkane is more preferably a polycycloalkane having a polycyclic skeleton of a bridged ring system such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane; or a polycycloalkane having a polycyclic skeleton of a condensed ring system such as a cyclic group having a steroid skeleton.

Among these, the cyclic aliphatic hydrocarbon group for ^R'201 is preferably a group in which one or more hydrogen atoms have been removed from a monocycloalkane or polycycloalkane, more preferably a group in which one hydrogen atom has been removed from a polycycloalkane, particularly preferably an adamantyl group or a norbornyl group, and most preferably an adamantyl group.

The linear or branched aliphatic hydrocarbon group which may be bonded to the alicyclic hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, even more preferably 1 to 4 carbon atoms, and most preferably 1 to 3 carbon atoms.
As the straight-chain aliphatic hydrocarbon group, a straight-chain alkylene group is preferable, and specific examples thereof include a methylene group [-CH ₂ -], an ethylene group [-(CH ₂ ) ₂ -], a trimethylene group [-(CH ₂ ) ₃ -], a tetramethylene group [-(CH ₂ ) ₄ -], a pentamethylene group [-(CH ₂ ) ₅ -], etc.
As the branched aliphatic hydrocarbon group, a branched alkylene group is preferable, and specific examples thereof include alkylmethylene groups such as -CH( _CH3 )-, -CH( _CH2CH3 )-, -C( _CH3 ) _2- , -C _{(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2- ; alkylethylene groups such as -CH ( CH3 ) CH2- ,} -CH( _{CH3 )} CH( _CH3 )-, -C _{( CH3} ) _{2CH2- ,} -CH( _{CH2CH3 ) CH2- , and -C} ( _CH2CH3 ) _{2 - CH2-} ; alkyltrimethylene groups such as -CH( _CH3 ) _CH2CH2CH2- , _-CH2CH ( _CH3 ) _CH2CH2- , etc.; and alkylalkylene groups such as alkyltetramethylene groups such as -CH( _CH3 ) _{CH2CH2CH2- , -CH2CH} (CH3) _CH2CH2- , etc. The alkyl group in the alkylalkylene group is preferably a linear alkyl group having 1 to 5 carbon atoms.

A chain alkyl group which may have a substituent:
The chain alkyl group of ^R'201 may be either linear or branched.
The linear alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 10 carbon atoms. Specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decanyl group, an undecyl group, a dodecyl group, a tridecyl group, an isotridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, an isohexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, an icosyl group, a henicosyl group, and a docosyl group.
The branched alkyl group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms, and most preferably 3 to 10 carbon atoms. Specific examples include a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

A chain alkenyl group which may have a substituent:
The chain alkenyl group of ^R'201 may be either linear or branched, and preferably has 2 to 10 carbon atoms, more preferably 2 to 5, even more preferably 2 to 4, and particularly preferably 3. Examples of linear alkenyl groups include vinyl groups, propenyl groups (allyl groups), and butynyl groups. Examples of branched alkenyl groups include 1-methylvinyl groups, 2-methylvinyl groups, 1-methylpropenyl groups, and 2-methylpropenyl groups.
Of the above chain alkenyl groups, linear alkenyl groups are preferred, vinyl groups and propenyl groups are more preferred, and vinyl groups are particularly preferred.

Examples of the substituent in the cyclic group, chain alkyl group or alkenyl group of ^R'201 include an alkoxy group, a halogen atom, a halogenated alkyl group, a hydroxyl group, a carbonyl group, a nitro group, an amino group, an oxo group, the cyclic group in ^R'201 above, an alkylcarbonyl group, a thienylcarbonyl group, etc.

Among these, ^R'201 is preferably a cyclic group which may have a substituent, or a chain alkyl group which may have a substituent.

When R ²⁰¹ to R ²⁰³ , R ²⁰⁶ to R ²⁰⁷ , and R ²¹¹ to R ²¹² are bonded to each other to form a ring together with the sulfur atom in the formula, they may be bonded via a heteroatom such as a sulfur atom, an oxygen atom or a nitrogen atom, or a functional group such as a carbonyl group, -SO-, -SO ₂ -, -SO ₃ -, -COO-, -CONH- or -N(R _N )- (wherein R _N is an alkyl group having 1 to 5 carbon atoms). As for the ring formed, one ring containing the sulfur atom in the ring skeleton in the formula is preferably a 3- to 10-membered ring including the sulfur atom, and particularly preferably a 5- to 7-membered ring. Specific examples of the ring formed include a thiophene ring, a thiazole ring, a benzothiophene ring, a thianthrene ring, a benzothiophene ring, a dibenzothiophene ring, a 9H-thioxanthene ring, a thioxanthone ring, a thianthrene ring, a phenoxathiin ring, a tetrahydrothiophenium ring, and a tetrahydrothiopyranium ring.

In the formula (ca-3), R ²⁰⁸ to R ²⁰⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and when they represent an alkyl group, they may be mutually bonded to form a ring.

In the above formula (ca-3), R ²¹⁰ is an aryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or an —SO ₂ —-containing cyclic group which may have a substituent.
The aryl group for R ²¹⁰ includes unsubstituted aryl groups having 6 to 20 carbon atoms, and is preferably a phenyl group or a naphthyl group.
The alkyl group for R ²¹⁰ is preferably a chain or cyclic alkyl group having 1 to 30 carbon atoms.
The alkenyl group for R ²¹⁰ preferably has 2 to 10 carbon atoms.

In the above formulae (ca-4) and (ca-5), Y ²⁰¹ each independently represents an arylene group, an alkylene group or an alkenylene group.
Examples of the arylene group for Y ²⁰¹ include groups in which one hydrogen atom has been removed from the aryl groups exemplified as the aromatic hydrocarbon group for R′ ²⁰¹ .
Examples of the alkylene group and alkenylene group for Y ²⁰¹ include groups in which one hydrogen atom has been removed from the groups exemplified as the chain alkyl group and chain alkenyl group for R' ²⁰¹ .

In the above formulas (ca-4) and (ca-5), x is 1 or 2.
W ²⁰¹ is a (x+1)-valent linking group, that is, a divalent or trivalent linking group.
The divalent linking group in W ²⁰¹ is preferably a divalent hydrocarbon group which may have a substituent, and is preferably the same as the divalent hydrocarbon group which may have a substituent exemplified by R ^EP in the above formula (A1). The divalent linking group in W ²⁰¹ may be linear, branched, or cyclic, and is preferably cyclic. Among them, a group in which two carbonyl groups are combined at both ends of an arylene group, or a group consisting of only an arylene group is preferred. Examples of the arylene group include a phenylene group and a naphthylene group, and a phenylene group is particularly preferred.
Examples of the trivalent linking group in W ²⁰¹ include a group in which one hydrogen atom has been removed from the divalent linking group in W ²⁰¹ , a group in which the divalent linking group is further bonded to the divalent linking group, etc. As the trivalent linking group in ^{W 201} , a group in which two carbonyl groups are bonded to an arylene group is preferable.

Specific examples of suitable cations represented by the formula (ca-1) include the cations represented by the following formulas (ca-1-1) to (ca-1-24).

［式中、Ｒ”^２０１は、水素原子又は置換基である。該置換基としては、前記Ｒ^２０１～Ｒ^２０７、およびＲ^２１０～Ｒ^２１２が有していてもよい置換基として挙げたものと同様である。］

[In the formula, R″ ²⁰¹ is a hydrogen atom or a substituent. Examples of the substituent are the same as those exemplified as the substituents that may be possessed by R ²⁰¹ to R ²⁰⁷ and R ²¹⁰ to R ^212. ]

As the cation represented by the formula (ca-1), the cations represented by the following general formulas (ca-1-25) to (ca-1-35) are also preferred.

［式中、Ｒ’^２１１はアルキル基である。Ｒ^ｈａｌは、水素原子又はハロゲン原子である。］

[In the formula, ^R'211 is an alkyl group. ^Rhal is a hydrogen atom or a halogen atom.]

As the cation represented by the formula (ca-1), the cations represented by the following chemical formulas (ca-1-36) to (ca-1-47) are also preferred.

Specific examples of suitable cations represented by the formula (ca-2) include diphenyliodonium cation, bis(4-tert-butylphenyl)iodonium cation, etc.

Specific examples of suitable cations represented by the formula (ca-3) include the cations represented by the following formulas (ca-3-1) to (ca-3-6).

Specific examples of suitable cations represented by the formula (ca-4) include the cations represented by the following formulas (ca-4-1) to (ca-4-2).

As the cation represented by the formula (ca-5), the cations represented by the following general formulas (ca-5-1) to (ca-5-3) are also preferred.

［式中、Ｒ’^２１２はアルキル基又は水素原子である。Ｒ’^２１１はアルキル基である。］

[In the formula, ^R'212 is an alkyl group or a hydrogen atom. ^R'211 is an alkyl group.]

Among the above, the cation portion [(Q ^q+ ) _1/q ] is preferably a cation represented by general formula (ca-1), more preferably a cation represented by each of formulas (ca-1-1) to (ca-1-47), and even more preferably a cation represented by each of formulas (ca-1-25), (ca-1-29), (ca-1-35) and (ca-1-47).

Component (I2) The component (I2) is a compound represented by the following general formula (I2-1) or (I2-2).

［式中、Ｒ^ｂ０５は、置換基を有していてもよいフッ素化アルキル基、又はフッ素原子である。複数のＲ^ｂ０５は、互いに同一であってもよく異なっていてもよい。ｑは１以上の整数であって、Ｑ^ｑ＋は、ｑ価の有機カチオンである。］

[In the formula, R ^b05 is a fluorinated alkyl group which may have a substituent, or a fluorine atom. Multiple R ^b05 may be the same or different from each other. q is an integer of 1 or more, and Q ^q+ is a q-valent organic cation.]

［式中、Ｒ^ｂ０６は、置換基を有していてもよいフッ素化アルキル基、又はフッ素原子である。複数のＲ^ｂ０６は、互いに同一であってもよく異なっていてもよい。ｑは１以上の整数であって、Ｑ^ｑ＋は、ｑ価の有機カチオンである。］

[In the formula, R ^b06 is a fluorinated alkyl group which may have a substituent, or a fluorine atom. Multiple R ^b06 may be the same or different from each other. q is an integer of 1 or more, and Q ^q+ is a q-valent organic cation.]

... Anion Moiety In the formula (I2-1), R ^b05 represents a fluorine atom or a fluorine-containing alkyl ^group which may have a substituent.
The fluorinated alkyl group for R ^b05 preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and even more preferably 1 to 5. Specific examples include alkyl groups having 1 to 5 carbon atoms in which some or all of the hydrogen atoms have been substituted with fluorine atoms.
Among these, R ^b05 is preferably a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms, more preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and further preferably a fluorine atom, a trifluoromethyl group or a pentafluoroethyl group.

The anion portion of the compound represented by formula (I2-1) is preferably represented by the following general formula (b0-2a):

［式中、Ｒ^ｂｆ０５は、置換基を有していてもよいフッ素化アルキル基である。ｎｂ^１は、１～５の整数である。］

[In the formula, R ^bf05 is a fluorinated alkyl group which may have a substituent, and nb ¹ is an integer of 1 to 5.]

In formula (b0-2a), the optionally substituted fluorinated alkyl group in R ^bf05 is the same as the optionally substituted fluorinated alkyl group exemplified for R ^b05 above.
In formula (b0-2a), ^nb1 is preferably an integer of 1 to 4, more preferably an integer of 2 to 4, and most preferably 3.

In the formula (I2-2), R ^b06 is a fluorine atom or a fluorine-containing alkyl ^group which may have a substituent.
The fluorinated alkyl group for R ^b06 preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and even more preferably 1 to 5. Specific examples include alkyl groups having 1 to 5 carbon atoms in which some or all of the hydrogen atoms have been substituted with fluorine atoms.
Among these, R ^b06 is preferably a fluorine atom or a fluorinated alkyl group having 1 to 5 carbon atoms, more preferably a fluorine atom or a perfluoroalkyl group having 1 to 5 carbon atoms, and even more preferably a fluorine atom.

...Cation Moiety In formula (I2-1) and formula (I2-2), q is an integer of 1 or more, and each Q ^q+ is independently a q-valent organic cation.
Examples of this Q ^q+ include those similar to those of formula (I1) above. Among them, the cation represented by general formula (ca-1) is preferable, the cations represented by each of formulas (ca-1-1) to (ca-1-47) are more preferable, and the cations represented by each of formulas (ca-1-25), (ca-1-29), (ca-1-35), and (ca-1-47) are even more preferable.

Component (I3) The component (I3) is a compound represented by the following general formula (I3-1) or (I3-2).

［式中、Ｒ^ｂ１１～Ｒ^ｂ１２は、ハロゲン原子以外の置換基を有していてもよい環式基、ハロゲン原子以外の置換基を有していてもよい鎖状のアルキル基、又はハロゲン原子以外の置換基を有していてもよい鎖状のアルケニル基である。ｍは１以上の整数であって、Ｍ^ｍ＋はそれぞれ独立にｍ価の有機カチオンである。］

[In the formula, R ^b11 to R ^b12 are a cyclic group which may have a substituent other than a halogen atom, a chain alkyl group which may have a substituent other than a halogen atom, or a chain alkenyl group which may have a substituent other than a halogen atom, m is an integer of 1 or more, and each M ^m+ is independently an m-valent organic cation.]

{Component (I3-1)}
... Anion portion In formula (I3-1), R ^b12 is a cyclic group which may have a substituent other than a halogen atom, a chain alkyl group which may have a substituent other than a halogen atom, or a chain alkenyl group which may have a substituent other than a halogen atom, and examples of this include the cyclic groups, chain alkyl groups, and chain alkenyl groups in the explanation of ^R'201 above which have no substituent or which have a substituent other than a halogen atom.
R ^b12 is preferably a chain alkyl group which may have a substituent other than a halogen atom, or an aliphatic cyclic group which may have a substituent other than a halogen atom.
The chain alkyl group preferably has 1 to 10 carbon atoms, and more preferably has 3 to 10 carbon atoms. The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, or the like (which may have a substituent other than a halogen atom); or a group in which one or more hydrogen atoms have been removed from camphor, or the like.
The hydrocarbon group of R ^b12 may have a substituent other than a halogen atom, and examples of the substituent include the same as the substituent other than a halogen atom that may be possessed by the hydrocarbon group (aromatic hydrocarbon group, aliphatic cyclic group, chain alkyl group) in R ^b11 of formula (I3-2) above.
The phrase "may have a substituent other than a halogen atom" as used herein not only excludes the case where a substituent consists of only halogen atoms, but also excludes the case where a substituent contains at least one halogen atom (for example, the case where the substituent is a fluorinated alkyl group, etc.).

Specific examples of preferred anion moieties of component (I3-1) are shown below.

...Cation Moiety In formula (I3-1), M ^m+ is an m-valent organic cation.
Suitable examples of the organic cation of M ^m+ include the same cations as those represented by the above general formulae (ca-1) to (ca-5), and among these, the cation represented by the above general formula (ca-1) is more preferred. Among these, a sulfonium cation in which at least one of R ²⁰¹ , R ²⁰² and R ²⁰³ in the above general formula (ca-1) is an organic group having 16 or more carbon atoms which may have a substituent (an aryl group, a heteroaryl group, an alkyl group or an alkenyl group) is particularly preferred because it improves resolution and roughness characteristics.
The substituent that the organic group may have is the same as described above, and examples thereof include an alkyl group, a halogen atom, a halogenated alkyl group, a carbonyl group, a cyano group, an amino group, an oxo group (═O), an aryl group, and groups represented by each of the above formulas (ca-r-1) to (ca-r-10).
The number of carbon atoms in the organic group (aryl group, heteroaryl group, alkyl group or alkenyl group) is preferably 16 to 25, more preferably 16 to 20, and particularly preferably 16 to 18. Suitable examples of the organic cation of M ^m+ include the cations represented by the above formulas (ca-1-25), (ca-1-26), (ca-1-28) to (ca-1-36), (ca-1-38), (ca-1-46) and (ca-1-47).

{Component (I3-2)}
... Anion portion In formula (I3-2), R ^b11 is a cyclic group which may have a substituent other than a halogen atom, a chain alkyl group which may have a substituent other than a halogen atom, or a chain alkenyl group which may have a substituent other than a halogen atom, and examples of this include the cyclic groups, chain alkyl groups, and chain alkenyl groups in the explanation of ^R'201 above, which have no substituent or have a substituent other than a halogen atom.

Among these, R ^b11 is preferably an aromatic hydrocarbon group which may have a substituent other than a halogen atom, an aliphatic cyclic group which may have a substituent other than a halogen atom, or a chain alkyl group which may have a substituent other than a halogen atom. The substituents which these groups may have include a hydroxyl group, an oxo group, an alkyl group, an aryl group, a lactone-containing cyclic group, an ether bond, an ester bond, or a combination thereof.
When an ether bond or an ester bond is contained as a substituent, it may be connected via an alkylene group, and in this case, the substituent is preferably a linking group represented by each of the following general formulas (y-al-1) to (y-al-7).

［式中、Ｖ’^１０１は単結合または炭素数１～５のアルキレン基であり、Ｖ’^１０２は炭素数１～３０の２価の飽和炭化水素基である。］

[In the formula, V' ¹⁰¹ is a single bond or an alkylene group having 1 to 5 carbon atoms, and V' ¹⁰² is a divalent saturated hydrocarbon group having 1 to 30 carbon atoms.]

The divalent saturated hydrocarbon group for V' ¹⁰² is preferably an alkylene group having 1 to 30 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms.

The alkylene group in ^V'101 and ^V'102 may be a linear alkylene group or a branched alkylene group, with a linear alkylene group being preferred.
Specific examples of the alkylene group in V' ¹⁰¹ and V' ¹⁰² include a methylene group [-CH ₂ -]; alkylmethylene groups such as -CH(CH ₃ )-, -CH(CH ₂ CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CH ₃ )(CH ₂ CH ₃ )-, -C(CH ₃ )(CH ₂ CH ₂ CH ₃ )-, and -C(CH ₂ CH ₃ ) ₂ -; an ethylene group [-CH ₂ CH ₂ -]; alkylethylene groups such as -CH(CH ₃ )CH ₂ -, -CH(CH ₃ )CH(CH ₃ )-, -C(CH ₃ ) ₂ CH ₂ -, and -CH(CH ₂ CH ₃ )CH ₂ -; a trimethylene group (n-propylene group) [-CH ₂ CH _2CH2- ]; alkyl trimethylene groups such as _-CH ( _CH3 ) _CH2CH2- and _-CH2CH ( _{CH3 ) CH2-} ; tetramethylene group _{[ -CH2CH2CH2CH2- ]} ; alkyl tetramethylene groups _such as -CH _{( CH3 ) CH2CH2CH2- and -CH2CH ( CH3 ) CH2CH2-} ; _{pentamethylene} group [ _{-CH2CH2CH2CH2CH2CH2-} ] _.
In addition, some of the methylene groups in the alkylene group in V' ¹⁰¹ or V' ¹⁰² may be substituted with a divalent aliphatic cyclic group having 5 to 10 carbon atoms. The aliphatic cyclic group is preferably a divalent group in which one hydrogen atom has been further removed from the cyclic aliphatic hydrocarbon group of R' ²⁰¹ (a monocyclic alicyclic hydrocarbon group, a polycyclic alicyclic hydrocarbon group), and more preferably a cyclohexylene group, a 1,5-adamantylene group, or a 2,6-adamantylene group.

The aromatic hydrocarbon group is more preferably a phenyl group or a naphthyl group.
The aliphatic cyclic group is more preferably a group in which one or more hydrogen atoms have been removed from a polycycloalkane such as adamantane, norbornane, isobornane, tricyclodecane, or tetracyclododecane.
The chain alkyl group preferably has 1 to 10 carbon atoms. Specific examples of the chain alkyl group include linear alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group; and branched alkyl groups such as a 1-methylethyl group, a 1-methylpropyl group, a 2-methylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, and a 4-methylpentyl group.

R ^b11 is preferably a cyclic group which may have a substituent other than a halogen atom.
Preferred examples of the anion moiety of the component (I3-2) are given below.

...Cation Moiety In formula (I3-2), M ^m+ is an m-valent organic cation and is the same as M ^m+ in formula (I3-1).

In addition, from the viewpoints of increasing the elasticity of the resin film and facilitating the formation of a fine structure without residue, the component (I) is preferably a photoinitiator that generates an acid having a pKa (acid dissociation constant) of -5 or less upon exposure. By using a photoinitiator that generates an acid having a pKa of more preferably -6 or less, and even more preferably -8 or less, it becomes possible to obtain high sensitivity to exposure. The lower limit of the pKa of the acid generated by the component (I) is preferably -15 or more. By using a photoinitiator that generates an acid having such a suitable pKa, it becomes easier to achieve high sensitivity.
Here, "pKa (acid dissociation constant)" refers to a value generally used as an index indicating the acid strength of a target substance. In this specification, pKa is a value at a temperature condition of 25°C. The pKa value can be determined by measurement using a known method. A calculated value using known software such as "ACD/Labs" (product name, manufactured by Advanced Chemistry Development Co., Ltd.) can also be used.

Specific examples of suitable components (I) are given below.

As the component (I), one type may be used alone, or two or more types may be used in combination.
The component (I) preferably contains two or more members selected from the group consisting of the components (I1), (I2) and (I3).
Among these, it is more preferable to use the component (I) in combination with the component (I1) and the component (I2).Alternatively, it is more preferable to use the component (I) in combination with one or more selected from the group consisting of the component (I1) and the component (I2) and the component (I3).

The content of the component (I) is preferably 0.5 to 6.0 parts by mass, more preferably 1.0 to 5.0 parts by mass, and even more preferably 1.0 to 3.0 parts by mass, per 100 parts by mass of the component (A).
When the content of the component (I) is equal to or greater than the lower limit of the preferred range, sufficient sensitivity is obtained, and the lithography properties of the pattern are further improved. In addition, the strength of the cured film is further increased. On the other hand, when the content is equal to or less than the upper limit of the preferred range, the sensitivity is appropriately controlled, and a pattern with a good shape is easily obtained.

Other Components The photosensitive resin film of the present embodiment may contain other components, if necessary, in addition to the components (A) and (I).
If desired, the photosensitive resin film of the embodiment may appropriately contain miscible additives, such as metal oxides, sensitizer components, silane coupling agents, solvents, additional resins for improving the performance of the film, dissolution inhibitors, basic compounds, plasticizers, stabilizers, colorants, and antihalation agents.

Metal Oxide The photosensitive resin film of the present embodiment contains a metal oxide (hereinafter also referred to as "component (M)") in addition to components (A) and (I), thereby obtaining a cured film with increased strength. In addition, a high-resolution pattern with a good shape can be formed.
Examples of the component (M) include oxides of metals such as silicon (metallic silicon), titanium, zirconium, hafnium, etc. Among these, oxides of silicon are preferred, and among these, it is more preferred to use silica, and it is particularly preferred to use silica as a filler.

The component (M) is preferably in the form of particles.
The particulate (M) component is preferably a particle group having a volume average particle diameter of 5 to 40 nm, more preferably a particle group having a volume average particle diameter of 5 to 30 nm, and even more preferably a particle group having a volume average particle diameter of 10 to 20 nm.
When the volume average particle size of the component (M) is at least the lower limit of the preferred range, the strength of the cured film tends to be increased, whereas when it is at most the upper limit of the preferred range, residues are less likely to be generated during pattern formation, making it easier to form a pattern with higher resolution.

The particle size of the (M) component may be appropriately selected depending on the exposure light source. It is generally believed that particles with a particle size of 1/10 or less of the wavelength of light are not affected by light scattering. For this reason, for example, when forming a microstructure by photolithography using i-line (365 nm), it is preferable to use a particle group (particularly preferably a silica particle group) with a primary particle size (volume average value) of 10 to 20 nm as the (M) component.

As the component (M), one type may be used alone, or two or more types may be used in combination.
The content of the component (M) is preferably 10 to 30 parts by mass, and more preferably 15 to 25 parts by mass, per 100 parts by mass of the component (A).
When the content of the (M) component is at least the lower limit of the above-mentioned preferred range, the strength of the cured film is further increased, whereas when the content is at most the upper limit of the above-mentioned preferred range, the flowability of the photosensitive resin composition is easily maintained.

When the photosensitive resin film of the present embodiment contains the component (M), the content of the component (I) is preferably 1 to 5 parts by mass, more preferably 1.1 to 4 parts by mass, and even more preferably 1.5 to 3 parts by mass, per 100 parts by mass of the total amount of the components (A) and (M).
When the content of the component (I) is within the above-mentioned preferred range, the strength of the cured film is further increased, making it easier to form a high-resolution pattern with a good shape.

In the photosensitive resin film of the present embodiment, the proportion of the content of the component (A) in the total content of the component (A), the component (I), and the component (M) is preferably 35 to 90 mass %, more preferably 40 to 85 mass %, and even more preferably 45 to 80 mass %.
When the content of the component (A) is within the above-mentioned preferred range, the strength of the cured film is increased, and the film properties (such as lamination properties) when formed into a photosensitive resist film are improved.

Sensitizer Component The photosensitive resin film of the embodiment may further contain a sensitizer component.
The sensitizer component is not particularly limited as long as it can absorb energy due to exposure and transmit the energy to another substance.
Specific examples of the sensitizer component that can be used include benzophenone-based photosensitizers such as benzophenone and p,p'-tetramethyldiaminobenzophenone, carbazole-based photosensitizers, acetophene-based photosensitizers, naphthalene-based photosensitizers such as 1,5-dihydroxynaphthalene, phenol-based photosensitizers, anthracene-based photosensitizers such as 9-ethoxyanthracene, and known photosensitizers such as biacetyl, eosin, rose bengal, pyrene, phenothiazine, and anthrone.
The sensitizer component may be used alone or in combination of two or more kinds.
When a sensitizer component is added to the photosensitive resin film of the embodiment, the content of the sensitizer component is preferably 0.1 to 15 parts by mass, more preferably 0.3 to 10 parts by mass, and even more preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of component (A).
When the content of the sensitizer component is within the above preferred range, the sensitivity and resolution can be further improved.

Silane Coupling Agent The photosensitive resin film of the embodiment may further contain an adhesion aid to improve adhesion to the support, and a silane coupling agent is preferred as the adhesion aid.
Examples of the silane coupling agent include silane coupling agents having reactive substituents such as a carboxy group, a methacryloyl group, an isocyanate group, an epoxy group, etc. Specific examples include trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc.
The silane coupling agents may be used alone or in combination of two or more kinds.
When a silane coupling agent is added to the photosensitive resin film of the embodiment, the content of the silane coupling agent is preferably 2.5 to 20 parts by mass, more preferably 3 to 15 parts by mass, and even more preferably 3 to 10 parts by mass, relative to 100 parts by mass of component (A).
When the content of the silane coupling agent is within the above-mentioned preferred range, the strength of the cured film is further increased, and in addition, the adhesion between the cured film and the support is further increased.

<Solvent>
The photosensitive resin film of the embodiment can be produced by dissolving or dispersing a photosensitive material in a solvent (hereinafter referred to as "component (S)").
Examples of the component (S) include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone (MEK), cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, and 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, and dipropylene glycol monoacetate; polyhydric ethers such as monoalkyl ethers, monomethyl ethers, monoethyl ethers, monopropyl ethers, and monobutyl ethers of the polyhydric alcohols or the compounds having an ester bond, and compounds having an ether bond such as monophenyl ethers. Examples of the organic solvent include derivatives of alcohols [among which, methoxybutyl acetate, propylene glycol monomethyl ether acetate (PGMEA), and propylene glycol monomethyl ether (PGME) are preferred]; cyclic ethers such as dioxane; esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, and ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, and mesitylene; and dimethyl sulfoxide (DMSO).
The component (S) may be used alone or as a mixed solvent of two or more kinds.

There are no particular limitations on the amount of component (S) used, and it is set appropriately according to the thickness of the coating film so long as the amount is a concentration that allows coating on a substrate or the like.
The content of the component (S) in the photosensitive resin composition is preferably from 1 to 25% by mass, and more preferably from 5 to 20% by mass, relative to the total amount (100% by mass) of the photosensitive resin composition.

(Manufacturing method of hollow package)
A manufacturing method according to a second aspect of the present invention is a method for manufacturing a hollow package, which includes a step of sealing the hollow structure manufactured by the manufacturing method according to the first aspect described above with a sealing material to obtain a hollow package.

As the sealing material, for example, a resin composition can be used. The resin used for the sealing material is not particularly limited as long as it can at least one of seal and insulate the hollow structure, and examples thereof include epoxy-based resins and silicone-based resins.
The sealing material may contain other components such as a filler in addition to the resin.

The method for sealing the hollow structure with a sealing material is not particularly limited, and the heated and melted sealing material is supplied onto the hollow structure so as to cover the hollow structure, and then compression molded to produce a hollow package having a sealing material layer provided on the hollow structure.
The sealing material layer has a function of protecting the MEMS, wiring parts, and the like in the hollow structure from the external environment.

The hollow package manufactured by the manufacturing method according to this embodiment includes the hollow structure 100 manufactured by the manufacturing method according to the first embodiment described above, and therefore the occurrence of defects such as deformation of the hollow structure during sealing, when connecting the conductor pattern and the lead frame together, and when separating the substrate by dicing, etc., is suppressed. Therefore, the space inside the hollow structure is reliably maintained, and a highly reliable microdevice can be provided.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the description of each manufacturing example, "parts" refers to parts by mass.

<Preparation of negative photosensitive resin composition>
(Preparation Examples 1 to 4)
The components shown in Table 1 were mixed and dissolved, and the mixture was filtered using a PTFE filter (pore size 1 μm, manufactured by PALL Corporation) to prepare negative-type photosensitive resin compositions (MEK solutions with solid contents of approximately 84 to 86% by mass) for each example.

In Table 1, the abbreviations have the following meanings: The numbers in brackets [ ] indicate the blending amount of each component (parts by mass; solid content equivalent).
(A)-1: An epoxy group-containing resin represented by the following chemical formula (A11), product name "JER-157S70", manufactured by Mitsubishi Chemical Corporation.

(A)-2: A compound represented by the following chemical formula (m1-1), trade name "Celloxide 8000", manufactured by Daicel Corporation.
(A)-3: A compound represented by the following chemical formula (m2-1), trade name "TEPIC-VL", manufactured by Nissan Chemical Industries, Ltd.

(I)-1: A photoinitiator represented by the following chemical formula (I1-4), trade name "Irgacure 290", manufactured by BASF.
(I)-3: A photoinitiator represented by the following chemical formula (I1-1), product name "CPI-310B", manufactured by San-Apro Ltd.
(I)-4: A photoinitiator represented by the following chemical formula (I1-3), product name "CPI-410B", manufactured by San-Apro Ltd.
(I)-5: Photoinitiator represented by the following chemical formula (I2-1-2), product name "CPI-410S", manufactured by San-Apro Ltd.

(I)-2: Photoinitiator represented by the following chemical formula (I3-1-1). Product name: "HS-1CS", manufactured by San-Apro Ltd.

(C)-1: Silica filler. Product name "MEK-EC-2130Y", manufactured by Nissan Chemical Industries, Ltd. Primary particle diameter φ=15 nm (volume average value). Methyl ethyl ketone dispersion with a silica component concentration of 31% by mass.
(D)-1: Sensitizer. α-naphthol.
(E)-1: Silane coupling agent, product name "Shin-Etsu Silicone (registered trademark) OFS6040SILANE", manufactured by Shin-Etsu Chemical Co., Ltd.
(E)-2: Silane coupling agent, product name "Shin-Etsu Silicone (registered trademark) X-12-967C", manufactured by Shin-Etsu Chemical Co., Ltd.
(S)-1: Solvent. Methyl ethyl ketone.

<Method of manufacturing hollow structure>
As the substrate film, a PET film with a silicone-based surface release treatment (product name "A53", manufactured by Teijin Limited) was used.

Example 1
Step (0):
The negative photosensitive resin composition of Preparation Example 1 was applied onto the substrate film using an applicator, and the applied coating was heated in an oven at 60° C. for 5 minutes, and then baked (PAB) at 70° C. for 10 minutes to form a photosensitive resin film having a thickness of 30 μm, thereby obtaining a photosensitive resist film (1).
In addition, a stepped substrate having a recess on its surface was prepared.

Step (i):
The photosensitive resist film (1) was disposed so that the surface of the photosensitive resin film of the photosensitive resist film (1) covered the opening of the recess in the stepped substrate.

After step (i), the base film was peeled off from the photosensitive resin film of the photosensitive resist film (1).

Step (ii):
Next, the photosensitive resin film was exposed to 300 mJ/cm ² (i-line equivalent) using a Canon PLA-501 ghi-line aligner.

Step (iii):
The photosensitive resin film after exposure in the step (ii) was subjected to a heat treatment on a hot plate at a temperature of 90° C. for 5 minutes.

Step (iv):
The photosensitive resin film after the heat treatment in the step (iii) was paddle-developed at 23° C. using propylene glycol monomethyl ether acetate as a developer to form a negative pattern that would become a top plate portion.

Step (v):
The negative pattern after the step (iv) was further cured by performing a heat treatment in an oven under the Step Cure conditions described below, to obtain a hollow structure (the cross section in the height direction of the hollow structure portion is rectangular: length (height) 200 μm × width 500 μm) whose top plate portion is made of a cured product of the photosensitive resin film.

Heat treatment under step cure conditions:
Heat treatment is performed in an oven at 60°C for 60 minutes, then heat treatment is performed in an oven at 100°C for 30 minutes, followed by a further heat treatment in an oven at 160°C for 30 minutes, and then a heat treatment is performed in an oven at 200°C for 60 minutes.

Example 2
In the step (v), the negative pattern after the step (iv) was irradiated with ultraviolet light ^at 1000 mJ/cm2, and then subjected to a heat treatment in an oven at a temperature of 160° C. for 60 minutes. In the same manner as in Example 1, a hollow structure was obtained.

Example 3
A hollow structural body was obtained in the same manner as in Example 2, except that in the step (v), the amount of ultraviolet light irradiated onto the negative pattern after the step (iv) was changed to 5000 mJ/cm ² .

Example 4
A hollow structural body was obtained in the same manner as in Example 2, except that in the step (v), the amount of ultraviolet light irradiated onto the negative pattern after the step (iv) was changed to 10,000 mJ/cm ² .

Example 5
A hollow structural body was obtained in the same manner as in Example 1, except that the negative type photosensitive resin composition of Preparation Example 1 was changed to the negative type photosensitive resin composition of Preparation Example 2.

Example 6
A hollow structural body was obtained in the same manner as in Example 1, except that the negative type photosensitive resin composition of Preparation Example 1 was changed to the negative type photosensitive resin composition of Preparation Example 3.

(Example 7)
A hollow structural body was obtained in the same manner as in Example 1, except that the negative type photosensitive resin composition of Preparation Example 1 was changed to the negative type photosensitive resin composition of Preparation Example 4.

(Example 8)
A hollow structural body was obtained in the same manner as in Example 2, except that the negative type photosensitive resin composition of Preparation Example 1 was changed to the negative type photosensitive resin composition of Preparation Example 2.

(Example 9)
A hollow structural body was obtained in the same manner as in Example 2, except that the negative type photosensitive resin composition of Preparation Example 1 was changed to the negative type photosensitive resin composition of Preparation Example 3.

(Example 10)
A hollow structural body was obtained in the same manner as in Example 2, except that the negative type photosensitive resin composition of Preparation Example 1 was changed to the negative type photosensitive resin composition of Preparation Example 4.

(Comparative Example 1)
In the step (v), a hollow structural body was obtained in the same manner as in Example 1, except that the negative pattern after the step (iv) was further subjected to a heat treatment at 200° C. for 60 minutes in an oven.

(Comparative Example 2)
In the step (v), a hollow structural body was obtained in the same manner as in Example 1, except that the negative pattern after the step (iv) was further subjected to a heat treatment at 160° C. for 60 minutes in an oven.

(Comparative Example 3)
In the step (v), a hollow structural body was obtained in the same manner as in Example 5, except that the negative pattern after the step (iv) was further subjected to a heat treatment in an oven at 160° C. for 60 minutes.

(Comparative Example 4)
In the step (v), a hollow structural body was obtained in the same manner as in Example 6, except that the negative pattern after the step (iv) was further subjected to a heat treatment in an oven at 160° C. for 60 minutes.

(Comparative Example 5)
A hollow structural body was obtained in the same manner as in Example 7, except that in the step (v), the negative pattern after the step (iv) was further subjected to a heat treatment in an oven at 160° C. for 60 minutes.

<Evaluation>
The deformation and strength of the top plate of each of the hollow structures obtained were evaluated.
The evaluation was carried out by measuring the swelling of the top plate and the tensile modulus E* of the cured film constituting the top plate as follows.

[Top bulge]
The hollow structure immediately after manufacture was cut in the height direction, and the degree of deformation (top plate bulge) in the height direction of the hollow structure portion was measured using a Dektak surface step gauge.
The results are shown in Tables 2 to 4 as "top plate swelling (μm)" according to the following evaluation criteria. The value in parentheses indicates the amount of deformation (μm) at the location where the top plate swelling was greatest.
Evaluation criteria: ◯: The deformation in the height direction of the hollow structure portion was 5 μm or less.
×: Deformation of the hollow structure portion in the height direction exceeded 5 μm.

[Measurement of tensile modulus E* of cured film]
The tensile modulus E* of the cured film constituting the top plate of the hollow structural body obtained in the step (v) was measured as follows.
The cured film was peeled off from the silicon wafer, and the tensile modulus E* of the cured film at 175° C. was measured using the following evaluation device and measurement conditions. The results are shown in Tables 2 to 4 as "Tensile modulus E* (GPa)".
Evaluation device: Reogel E-4000 (manufactured by UBM)
Measurement conditions: tension mode, frequency 1.0 Hz, chuck distance 10 mm
The higher the tensile modulus E*, the higher the strength of the cured film.

From the results shown in Tables 2 and 4, in comparison with Examples 1 to 4 and Comparative Examples 1 and 2, which share the same negative photosensitive resin composition, it is clear that the hollow structures of Examples 1 to 4 all have low swelling of the top plate caused by the curing operation during their manufacture. In addition, it is clear that the hollow structures of Examples 1 to 4 have sufficient strength.
On the other hand, the hollow structure of Comparative Example 1 had sufficient strength, but was found to have a large bulge in the top plate due to the curing operation during its manufacture. The hollow structure of Comparative Example 2 was found to have a large bulge in the top plate due to the curing operation during its manufacture, and was also found to have inferior strength to the hollow structures of Examples 1 to 4.

From the results shown in Tables 3 and 4, it can be seen that, by comparing Examples 5 and 8, which share a common negative photosensitive resin composition, with Comparative Example 3, the hollow structures of Examples 5 and 8 had low swelling of the top plate caused by the curing operation during their manufacture. On the other hand, it was found that the hollow structure of Comparative Example 3 had a large swelling of the top plate caused by the curing operation during its manufacture.
It is also clear that the hollow structures of Examples 5 and 8 both have higher strength than the hollow structure of Comparative Example 3.

From the results shown in Tables 3 and 4, a comparison of Examples 6 and 9 and Comparative Example 4, which share a common negative photosensitive resin composition, shows that the hollow structures of Examples 6, 9, and Comparative Example 4 all have low top plate swelling caused by the curing operation during their manufacture. From the comparison of the two, it is seen that the hollow structures of Examples 6 and 9 have low top plate swelling caused by the curing operation during their manufacture, compared to the hollow structure of Comparative Example 4.
It is also clear that the hollow structures of Examples 6 and 9 both have higher strength than the hollow structure of Comparative Example 4.

From the results shown in Tables 3 and 4, a comparison of Examples 7 and 10, which share a common negative photosensitive resin composition, with Comparative Example 5 reveals that the hollow structures of Examples 7, 10, and Comparative Example 5 all have low top plate swelling caused by the curing operation during their manufacture. From the comparison of the two, it is seen that the hollow structures of Examples 7 and 10 have low top plate swelling caused by the curing operation during their manufacture, compared to the hollow structure of Comparative Example 5.
It is also clear that the hollow structures of Examples 7 and 10 both have higher strength than the hollow structure of Comparative Example 5.

Therefore, it was confirmed that by applying the present invention, deformation of the top plate due to the curing operation is suppressed, and a hollow structure with increased strength can be stably manufactured.

10 Substrate, 20 Side wall, 30 Photosensitive resin film, 40 Hardened body, 50 Base film, 60 Photomask, 80 Laminated film, 100 Hollow structure

Claims (4)

A method for manufacturing a hollow structural body including a recess and a top plate portion that closes an opening of the recess, comprising the steps of:
A step (0) of preparing a substrate having a recess on its surface and a photosensitive resist film having a negative photosensitive resin film containing an epoxy group-containing resin (A) and a photoinitiator (I) that generates an acid upon exposure;
(i) a step of disposing the photosensitive resist film such that a photosensitive resin film surface of the photosensitive resist film covers an opening surface of the recess in the substrate;
After the step (i), a step (ii) of exposing the photosensitive resin film to light;
a step (iii) of subjecting the photosensitive resin film after the step (ii) to a heat treatment;
(iv) developing the photosensitive resin film to form a negative pattern after the step (iii);
and (v) a step of subjecting the negative pattern after the step (iv) to a heat treatment to cure the negative pattern, thereby obtaining a hollow structural body in which the top plate portion is made of a cured body of the photosensitive resin film,
The heat treatment in the step (v) is carried out by an operation (y) of irradiating with ultraviolet light and then heating at a temperature of 100° C. or higher;
The epoxy group-containing resin (A) contains a resin (A1) represented by the following general formula (A1):
The method for producing a hollow structure, wherein the photoinitiator (I) contains at least one compound selected from the group consisting of a compound represented by the following general formula (I1) and a compound represented by the following general formula (I2) :

[In the formula, R ^p1 and R ^p2 are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Multiple R ^p1s may be the same as or different from each other. Multiple R ^p2s may be the same as or different from each other. _n1 is an integer of 1 to 5. R ^EP is an epoxy group-containing group. Multiple R ^EPs may be the same as or different from each other.]

[In the formula, R ^b01 to R ^b04 are each independently an aryl group which may have a substituent, or a fluorine atom. R ^b05 is a fluorinated alkyl group which may have a substituent, or a fluorine atom. The multiple R ^b05 may be the same or different. q is an integer of 1 or more, and each Q ^q+ is independently a q-valent organic cation.] The method for producing a hollow structural body according to claim 1, wherein the operation (y) comprises irradiating the substrate with ultraviolet light at 1000 to 10000 mJ/ ^cm2 , followed by heating the substrate at a temperature of 160°C or higher for 30 minutes or longer. A method for manufacturing a hollow structural body including a recess and a top plate portion that closes an opening of the recess, comprising the steps of:
A step (0) of preparing a substrate having a recess on its surface and a photosensitive resist film having a negative photosensitive resin film containing an epoxy group-containing resin (A) and a photoinitiator (I) that generates an acid upon exposure;
(i) a step of disposing the photosensitive resist film such that a photosensitive resin film surface of the photosensitive resist film covers an opening surface of the recess in the substrate;
After the step (i), a step (ii) of exposing the photosensitive resin film to light;
a step (iii) of subjecting the photosensitive resin film after the step (ii) to a heat treatment;
(iv) developing the photosensitive resin film to form a negative pattern after the step (iii);
and (v) a step of subjecting the negative pattern after the step (iv) to a heat treatment to cure the negative pattern, thereby obtaining a hollow structural body in which the top plate portion is made of a cured body of the photosensitive resin film,
The heat treatment in the step (v) is carried out by heating at a temperature of 50° C. or more and 125° C. or less for 10 minutes or more, and then further heating at a temperature of 160° C. or more for 30 minutes or more;
The epoxy group-containing resin (A) contains a resin (A1) represented by the following general formula (A1):
The method for producing a hollow structure, wherein the photoinitiator (I) contains at least one compound selected from the group consisting of a compound represented by the following general formula (I1) and a compound represented by the following general formula (I2) :

[In the formula, R ^p1 and R ^p2 are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Multiple R ^p1s may be the same as or different from each other. Multiple R ^p2s may be the same as or different from each other. _n1 is an integer of 1 to 5. R ^EP is an epoxy group-containing group. Multiple R ^EPs may be the same as or different from each other.]

[In the formula, R ^b01 to R ^b04 are each independently an aryl group which may have a substituent, or a fluorine atom. R ^b05 is a fluorinated alkyl group which may have a substituent, or a fluorine atom. The multiple R ^b05 may be the same or different. q is an integer of 1 or more, and each Q ^q+ is independently a q-valent organic cation.] A method for producing a hollow package, comprising a step of sealing, with a sealing material, a hollow structure produced by the method according to any one of claims 1 to 3 to obtain a hollow package.

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