JPH0215864B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a novel photosensitive heat-resistant material. [Prior Art] Conventionally, in the manufacture of semiconductors, insulating layers and passivation layers of solid-state devices are formed of inorganic materials such as silicon oxide by a CVD method.
Although it is used, it is necessary to form a thick layer because the smoothness is poor. Therefore, technology has been developed to use polymeric materials, which are superior in terms of lower stress, better smoothness, and higher purity than inorganic materials, as insulating layers and passivation layers for solid-state devices. It has been put to practical use in the manufacture of some semiconductor devices. The polymer materials used for these applications are required to have good heat resistance due to work processes such as die bonding, so it is necessary to use heat-resistant polymer materials, and polyimide resins, which have excellent heat resistance, are usually used. Thermosetting resins such as polysiloxane and organoladder polysiloxane are being considered. When thermosetting resin is used as an insulating layer or passivation layer for solid-state devices, it is necessary to perform microfabrication processes such as ventilation holes in the upper and lower conductor layers and through-holes for connection to external lead wires. However, this is generally carried out by chemical etching of a thermosetting resin using a photoresist as a mask. Therefore, patterning the thermosetting resin in the above process requires steps such as coating and peeling off photoresist, making the process itself extremely complicated (Japanese Patent Publication No. 1973-
44871, JP-A-56-125855, JP-A-56-125856, and JP-A-56-125857). [Summary of the Invention] In order to simplify the above-mentioned process, the purpose of the present invention is to provide a heat-resistant material that can be microfabricated by direct light, and has the following general formula (1): (In the formula, n is an integer from 2 to 100, and R ₁ represents a phenyl group or a lower alkyl group such as a methyl group, an ethyl group, or a propyl group) and the general formula (2): (In _the formula _, An organoladder polysiloxane obtained by reacting in an organic solvent with an unsaturated compound represented by the general formula (3): N ₃ −R ₄ −N ₃ (3) (wherein R ₄ represents a divalent organic group). [Embodiments of the invention] The organo ladder polysiloxane used in the present invention is a terminal hydroxy ladder type organopolysiloxane represented by the general formula (1), and has a degree of polymerization of 2.
-100, preferably 5-20. The organo-ladder polysiloxane having the ladder structure has extremely excellent heat resistance, but if the degree of polymerization is less than 2, it will not become an organo-ladder polysiloxane.
Poor heat resistance, if it exceeds 100, the organo ladder
Silicone compounds produced using polysiloxane have fewer crosslinking points, resulting in poor polymerizability. When the degree of polymerization is from 5 to 20, a silicone compound having excellent heat resistance and photopolymerizability can be obtained. The compound represented by the general formula (1) can be obtained by hydrolyzing trichlorosilane having a phenyl group or an alkyl group by a known method, and further requires a condensation catalyst such as potassium hydroxide, carbodiimides, or chloroformates. It can be used to synthesize compounds with arbitrary molecular weights. The unsaturated compound represented by the general formula (2) used in the present invention has the general formula (4): (wherein, X and m are the same as above) and the general formula (5): -Si(OR ₂ ) _l (R ₃ ) _3-l ( ₅ ) ₃ , l is the same as above). As X in the photosensitive group represented by general formula (4), a hydrogen atom, methyl group, ethyl group, or phenyl group is preferable from the viewpoint of photopolymerizability of the produced silicone compound, and m is 0 to 4. It is preferable from the viewpoint of heat resistance. On the other hand, R ₂ and R ₃ in the alkoxysilano group represented by general formula (5) include a methyl group, an ethyl group,
It is a lower alkyl group such as a propyl group,
It is preferable from the viewpoint of dealcoholization reactivity, etc., and l needs to be 1 to 3 because the alkoxysilano group is bonded to the photosensitive group represented by the general formula (3) and is an alkoxysilano group. Examples of the unsaturated compound represented by the general formula (2) include vinylmethoxysilane, vinylethoxysilane, vinylpropoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, allylmethoxysilane, and allylethoxysilane. , but not limited to these. In the present invention, a photopolymerizable ladder polysiloxane is produced by reacting an organoladder polysiloxane represented by general formula (1) with an unsaturated compound represented by general formula (2). That is, for example, for one hydroxyl group of organoladder polysiloxane,
Organoladder polysiloxane and an unsaturated compound are mixed at a ratio of 1 to 3 alkoxy groups in the unsaturated compound, a catalyst to accelerate the reaction is added, and the mixture is heated at a temperature of about 50 to 130°C for 5 to 20 hours. A silicone compound is produced by heating and stirring to cause a dealcoholization reaction between the hydroxyl group and the alkoxysilano group. As the catalyst used in the reaction, sulfuric acid, phosphoric acid, aluminum oxide, orthotitanate isopropyl ester, etc. can be used. The amount of the catalyst used is 0.01 to 100 parts (parts by weight, same hereinafter) of organoladder polysiloxane.
Preferably it is 5 parts. Since the organoladder polysiloxane used in the present invention is usually solid, it is preferable to use a solvent in the dealcoholization reaction. Examples of such solvents include ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone, aromatic hydrocarbon solvents such as benzene, toluene, and xylene, and N-methylpyrrolidone.
It is not limited to these. Examples of the bisazide compound represented by the general formula (3) used in the present invention include 2,6-di(p-azidobenzal)-4-methylcyclohexanone,
2,6-di(p-azidobenzal)cyclohexanone, 4,4'-diazidobenzalacetone, 4,
4'-diazidostilbene, 4,4'-diazidochalcone, 4,4'-diazidobenzophenone, 2,8
-diazidoacridine, 4,4'-diazidodiphenylmethane, etc., but are not limited to these. These bisazide compounds may be used alone or in combination of two or more. The photosensitive heat-resistant material of the present invention contains 0.1 of a bisazide compound represented by general formula (3), which is a photosensitive crosslinking agent, per equivalent of the photopolymerizable ladder polysiloxane.
Prepared by mixing ~2.0 equivalents. If the amount of the bisazide compound mixed is less than 0.1 equivalent, no effective crosslinking effect will occur, and if it exceeds 2.0 equivalent, the thermal stability of the obtained cured product will decrease. When the photosensitive heat-resistant material of the present invention is directly applied to a substrate and exposed to light, a clear relief pattern can be obtained, but when 0.01 to 10% by weight of a photosensitizer is added to the heat-resistant material, the photosensitivity increases significantly. do. Examples of the photosensitizer include cyanoacridine, 2-chloro-1,8-phthaloylnaphthalene, anthrathrone, 2'-bromo-1,2-benzaanthraquinone, and 2'-chloro-1,2-benzaanthraquinone. , 1,2-benzaanthraquinone, 1,8-dinitropyrene, 1-nitropyrene, Michler's ketone, etc., but are not limited to these. These photosensitizers may be used alone or in combination of two or more. The photosensitive heat-resistant material of the present invention is applied onto a glass plate or silicon wafer by spin coating using a spinner, and after pre-curing at 50 to 90°C, irradiation with light or radiation through a mask having a predetermined pattern, When the film is then developed with a ketone solvent such as methyl ethyl ketone or methyl isobutyl ketone or an aromatic hydrocarbon solvent such as benzene, toluene or xylene, the unexposed areas are washed away and a sharp relief pattern on the end face can be obtained. When the resulting relief pattern is further heat-treated at 200 to 400℃, it becomes heat resistant.
A cured product having a good pattern with excellent chemical resistance and electrical properties can be obtained. The photosensitive heat-resistant material of the present invention is not only useful as a passivation layer and interlayer insulation layer of semiconductors, and an insulation layer of magnetic heads, but also as a solder resist for printed circuits, a highly heat-resistant photoresist, a lift-off material, etc. It is also possible to apply to Next, the photosensitive heat-resistant material of the present invention will be explained based on Examples, but the present invention is not limited thereto. Production example 1 (Synthesis of terminal hydroxy ladder type organopolysiloxane) Phenyltrichlorosilane (C ₆ H ₅ SiCl ₃ ) 105.8
g (0.5 mol) dissolved in 200 ml of methyl isobutyl ketone, a stirrer and a thermometer were attached.
1 placed in a 4-necked flask while cooling in an ice bath
The mixture was gradually added dropwise to ion-exchanged water under stirring to effect hydrolysis. During the dropwise addition, the reaction temperature was maintained at 10° C. or lower, and it took 4 hours to complete the dropwise addition. Thereafter, the mixture was returned to room temperature and stirred for an additional 30 minutes to complete the hydrolysis reaction. After the stirring was stopped, the ketone layer was separated from the reaction solution separated into two layers, and then washed with ion-exchanged water several times until it became neutral. The solvent was removed from the solution and dried in a vacuum dryer at 150°C for 1 hour to form a white powder.
I got g. IR spectrum analysis of the white powder obtained revealed that OH absorption was observed at 3400 cm ^-1 and that it was found in the Journal of Polymer Science (J Polym.
Absorption attributed to the antisymmetric stretching vibration of Si—O—Si was observed at 1135 cm ⁻¹ and 1045 cm ⁻¹ as described in J. Sci., Vol. C-1, p. 83 (1963).
From these results, it was confirmed that the white powder obtained was a terminal hydroxy ladder type polysiloxane represented by general formula (1). The powder has a melting temperature of 90℃,
The molecular weight was approximately 1500 (n=6). Production example 2 (synthesis of terminal hydroxy ladder type organopolysiloxane) 3 equipped with a reflux condenser, stirrer and thermometer
10g of white powder obtained in Production Example 1 in a neck flask
After adding 30 ml of xylene and dissolving it to make it homogeneous, 0.4 g of ethyl chloroformate as a condensation catalyst was added and dissolved, and the mixture was reacted at 130°C for 5 hours. After the reaction was completed, the reaction mixture was cooled and poured into 10 times the amount (volume) of methanol to precipitate the polymer, which was separated and dried under reduced pressure (yield: 9 g). When the obtained polymer was analyzed by IR spectrum, OH absorption was observed at 3400 cm ^-1 and absorption attributed to antisymmetric stretching vibration of Si-O-Si was observed at 1135 cm ^-1 and 1045 cm ^-1 . From these results, it was confirmed that the obtained polymer was a terminal hydroxyl ladder polysiloxane. The molecular weight of the obtained polymer was about 3000 (n=12). Production Example 3 30g of terminal hydroxyphenyl ladder polysiloxane obtained in Production Example 1, vinyl ethoxysilane
Put 15.2 g and 50 g of toluene into a three-necked flask, attach a stirrer, thermometer, and cooler, and heat to about 110℃.
The mixture was stirred for 10 hours to react. After the reaction was completed, toluene was removed by vacuum distillation to obtain a white powder. IR of the obtained white powder (silicone compound)
When spectral analysis was performed, it was found that the absorption due to OH at 3400 cm ^-1 decreased compared to the raw material terminal hydroxyphenyl ladder type polysiloxane, and the absorption at 1270 cm ^-1 due to vinyl groups was newly observed. Production Example 4 30g of terminal hydroxyphenyl ladder polysiloxane obtained in Production Example 2, vinyl ethoxysilane
7.6 g and 50 g of toluene were reacted at approximately 110°C for 10 hours using the same equipment as in Production Example 3, and then
Pour into twice the volume of methanol to obtain a white precipitate. The yield was 92%. IR of the white precipitate (silicone compound) obtained
When spectral analysis was performed, it was found that the absorption due to OH at 3400 cm ^-1 decreased compared to the raw material terminal hydroxyphenyl ladder type polysiloxane, and the absorption at 1270 cm ^-1 due to vinyl groups was newly observed. Production Example 5 30g of terminal hydroxyphenyl ladder polysiloxane obtained in Production Example 2, allyl ethoxysilane
8.2 g and 50 g of toluene were reacted at 110° C. for 10 hours in the same manner as in Production Example 3, and then poured into 10 times the amount of methanol to obtain a white precipitate. The yield was 92%. IR of the white precipitate (silicone compound) obtained
When spectral analysis was performed, it was found that the absorption due to OH at 3400 cm ^-1 decreased compared to the raw material terminal hydroxyphenyl ladder type polysiloxane, and the absorption at 1620 cm ^-1 due to allyl groups was newly observed. Examples 1 to 5 The silicone compounds and bisazide compounds shown in Table 1 were dissolved in 70 g of toluene, coated uniformly on an aluminum plate using a spinner, and heated at 60°C for 15 minutes.
After drying for a minute (film thickness approximately 1μm), a 500W ultra-high pressure mercury lamp was used to remove the film through a prescribed mask at a distance of 30 minutes.
Ultraviolet irradiation was performed for the time shown in Table 1 in cm. After irradiation, it was immersed in methyl isobutyl ketone for 60 to 120 seconds to form a pattern. After observing the state of the resulting pattern, the sample was heat treated at 150°C for 60 minutes and then at 400°C for 30 minutes, and the blurring of the pattern and adhesion to the substrate were measured. The obtained cured product was also thermogravimetrically measured (in a nitrogen atmosphere, at a heating rate of 10° C./min). In addition, photosensitive heat-resistant materials (including solvents) can be used at room temperature in the dark.
Storage stability was measured after 3 months. The results are shown in Table 1. The blurring of the pattern after heat treatment is determined by observation with a scanning electron microscope, and if there is no blurring, it is considered acceptable.The adhesion of the pattern to the coated substrate after heat treatment is determined using a knife on the cured film. scratches are made in a checkerboard pattern and peeled using Scotch tape.If it does not peel off, it is judged as good.Storage stability is determined by measuring the patternability after storage using the same method as in the example, and if there is no difference from immediately after manufacturing. The quality was judged as good.

〔Effect of the invention〕

By using the photosensitive heat-resistant material of the present invention,
A patterned cured film having heat resistance can be formed, and the semiconductor manufacturing process can be simplified.

Claims (1)

[Claims] 1 General formula (1): (In the formula, n is an integer from 2 to 100, and R ₁ represents a phenyl group or a lower alkyl group such as a methyl group, an ethyl group, or a propyl group) and the general formula (2): (In _the formula _,
is an integer of 1 to 3) in an organic solvent and an organoladder polysiloxane obtained by reacting with an unsaturated compound represented by the general formula (3): N ₃ −R ₄ −N ₃ (3) ( A photosensitive heat-resistant material comprising a bisazide compound represented by the formula (in which R ₄ represents a divalent organic group).