JP7573003B2 - Metal mask manufacturing method, metal mask - Google Patents

Description

The present invention relates to a method for manufacturing a metal mask used in processes such as deposition, printing, and solder ball mounting, and to a metal mask manufactured by the method.

The deposition mask method is often used as a method for forming the light-emitting layer of an organic EL (Electroluminescence) element. In this deposition mask method, a deposition mask with holes removed at the locations of the substrate corresponding to the deposition sites is used to deposit an organic light-emitting material at desired locations on a substrate made of a transparent material such as glass.
Such deposition masks must be thin and must have a large number of deposition through-holes for passing the deposition material with high precision. In recent years, it has been proposed to form the deposition masks by electroforming.

In forming a mask by electroforming, a resist is placed in advance at many locations on the surface of the mother mold that will become the deposition holes, and then an electrodeposition layer made of an electroformable metal such as nickel that forms a mask is formed on the mother mold surface by electroforming, simultaneously forming a state in which many deposition holes are provided in a predetermined pattern. If necessary, a reinforcing frame is integrated by plating or the like to obtain the desired mask structure, and the mother mold is separated to complete the deposition mask.
An example of a conventional deposition mask manufactured using electroforming is disclosed in Japanese Patent Application Laid-Open No. 2005-15908.

JP 2005-15908 A

Conventional deposition masks have the structure shown in the above-mentioned patent document, and by using an electroforming technique to properly integrate the frame with the mask body, it is possible to suppress relative deformation between the mask and the substrate when heat is applied during the deposition process, and to prevent deterioration of the positional accuracy of the deposition formation.

However, in recent years, the market has been demanding even higher precision in deposition formations, leading to thinner masks and finer through-hole patterns, which has resulted in the impact of mask deformation becoming extremely large.

The present invention has been made to solve the above problems, and aims to provide a method for manufacturing a metal mask that can stably and accurately form the mask body, and a metal mask manufactured by this method.

The method for manufacturing a metal mask disclosed in the present invention is a method for manufacturing a metal mask having a mask body with a large number of through holes and a frame body for reinforcing the mask body, and includes a mask body forming process for forming the mask body and a joining process for joining the mask body and the frame body, and the mask body forming process includes a preheating process for preheating to a predetermined preheating temperature.

The mask body forming process also includes a resist layer forming process for forming a resist layer on the matrix, and an exposure process for exposing the resist layer to light, and includes a matrix preheating process for preheating the matrix to a predetermined preheat temperature before the exposure process.

In addition, in the exposure process, exposure is performed using an exposure device, and before the exposure process, a mold device preheating process is performed to preheat the inside of the exposure device to a predetermined preheat temperature.

In addition, in the exposure process, exposure is performed using a photomask having a predetermined pattern corresponding to the mask body, and a photomask preheating process is performed before the exposure process to preheat the photomask to a predetermined preheating temperature.

Also, the master mold, the exposure tool, and the photomask are preheated to the same temperature.

The maximum temperature reached inside the exposure device is set as the preheat temperature.

The mask body forming process further includes a primary pattern resist forming process in which the unexposed portions of the resist are removed to form a primary pattern resist after the exposure process, and a primary electrodeposition layer forming process in which a primary electrodeposition layer is formed by electroforming on the surface of the matrix that is not covered by the primary pattern resist, and the maximum temperature among the exposure temperature in the exposure process, the electroforming temperature in the primary electrodeposition layer forming process, and the deposition temperature in the deposition process using a metal mask is set as the preheat temperature.

The metal mask is also manufactured by the above-mentioned metal mask manufacturing method.

1 is a schematic cross-sectional view of an electroforming master mold according to a first embodiment of the present invention. 1 is a schematic plan view of a deposition mask manufactured using an electroforming master according to a first embodiment of the present invention. FIG. 1 is an explanatory diagram of a configuration of a main part of a deposition mask manufactured using an electroforming mother mold according to a first embodiment of the present invention; 3A to 3C are explanatory views of a process of forming an outer frame resist in the manufacture of an electroforming mother mold according to the first embodiment of the present invention. FIG. 2 is an explanatory diagram of a conductive layer forming step in the manufacture of an electroforming master according to the first embodiment of the present invention. FIG. 2 is an explanatory view of the first half of the adhesive layer forming process in the manufacture of an electroforming master according to the first embodiment of the present invention. FIG. 4 is an explanatory view of the second half of the adhesive layer forming process in the manufacture of an electroforming master according to the first embodiment of the present invention. 3A to 3C are explanatory views of a transfer process of an adhesive layer and a conductive layer onto a base portion in the manufacture of an electroforming master according to the first embodiment of the present invention. 1A to 1C are diagrams illustrating a primary pattern resist formation process in a deposition mask manufacturing process using an electroforming mother mold according to a first embodiment of the present invention. 4A to 4C are explanatory views of a primary electrodeposition layer formation process in a deposition mask manufacturing process using an electroforming mother mold according to the first embodiment of the present invention. 1A to 1C are diagrams illustrating a secondary pattern resist formation process in a deposition mask manufacturing process using an electroforming mother mold according to a first embodiment of the present invention. 4A to 4C are explanatory diagrams of a frame bonding and electrodeposited metal layer forming process in a deposition mask manufacturing process using an electroforming mother mold according to the first embodiment of the present invention. 4A to 4C are explanatory views of a process for separating a base portion of a mold and a part of a conductive layer in a deposition mask manufacturing process using an electroforming mold according to the first embodiment of the present invention. 1A to 1C are explanatory views of a process for separating a remaining conductive layer of a mold and a state in which unnecessary parts are removed from a deposition mask in a deposition mask manufacturing process using an electroforming mold according to a first embodiment of the present invention. 13 is an explanatory diagram showing the state where the formation of an adhesive layer is completed and the state where the transfer of the adhesive layer and the conductive layer to a base portion is completed in the manufacturing process of an electroforming mold according to a second embodiment of the present invention. FIG. 13 is an explanatory diagram showing another state where formation of an adhesive layer is completed and where transfer of an adhesive layer and a conductive layer to a base portion is completed in the manufacturing process of an electroforming mold according to a second embodiment of the present invention. FIG. 13A to 13C are explanatory views of the state in which formation of an adhesive layer is completed and the state in which transfer of an adhesive layer and a conductive layer to a base portion is completed in the manufacturing process of an electroforming mold according to a third embodiment of the present invention. 13 is an explanatory diagram showing another state where formation of an adhesive layer is completed and where transfer of an adhesive layer and a conductive layer to a base portion is completed in the manufacturing process of an electroforming mold according to a third embodiment of the present invention. FIG. 13 is an explanatory diagram showing yet another state in which formation of an adhesive layer is completed and transfer of an adhesive layer and a conductive layer to a base portion is completed in the manufacturing process of an electroforming mold according to a third embodiment of the present invention. FIG. 13 is an explanatory diagram of an adhesive layer forming step in the manufacture of an electroforming master according to a fourth embodiment of the present invention. FIG. 13 is an explanatory diagram showing the state where the formation of an adhesive layer is completed and the state where the transfer of the adhesive layer and the conductive layer to a base portion is completed in the manufacturing process of an electroforming mold according to a fourth embodiment of the present invention. FIG.

(First embodiment of the present invention)
1 to 14, an electroforming matrix according to a first embodiment of the present invention will be described. In this embodiment, an example will be described in which the electroforming matrix is used to form a deposition mask for an organic EL element by electroforming.

In each of the drawings, the electroforming mother mold 10 according to this embodiment includes a base portion 11 which is a conductive metal flat plate, a sheet-like adhesive layer 12 which is disposed on the base portion 11, and a sheet-like conductive layer 13 which is adhered to the base portion 11 via the adhesive layer 12 and has a multi-layer structure.
The configuration includes:

The base portion 11 is a plate-like body made of metal such as stainless steel such as SUS430, brass, steel, etc. The thickness of the base portion is preferably about 1 mm.
The base portion 11 may also be made of 42 alloy (42% nickel-iron alloy) or Invar (3
Alternatively, the base 11 may be made of a material having a low thermal expansion coefficient, such as SUS 430, SUS 430, or a similar material. The base 11 may be made of an insulating substrate, such as a glass plate or a resin plate, on whose surface a metal film made of a conductive metal, such as chromium or titanium, is formed.

The adhesive layer 12 has a two-layer structure consisting of a first resist 12a and a second resist 12b, and serves to bond and integrate the base portion 11 and the conductive layer 13 together.
The first resist 12a has a frame-shaped portion 12c in a predetermined range from the outer periphery, for example, a frame-shaped portion in a range of 20 mm wide from the outer periphery, which is in an uncured state having adhesiveness, and a middle portion 12d other than the frame-shaped portion 12c in a predetermined range from the outer periphery.
The base portion 11 is in a semi-cured state in which the adhesiveness and volume change over time are smaller than in the uncured state.
The configuration is such that the sensor is disposed in contact with the sensor.

The second resist 12b, like the first resist 12a, is configured so that a frame-shaped portion 12e within a predetermined range from the outer peripheral edge is in an uncured state having adhesive properties, and the remaining intermediate portion 12f is in a cured state with no change in volume over time, and is disposed in contact with the conductive layer 13.

Specifically, the first resist 12a and the second resist 12b are formed by placing a negative photosensitive dry film resist on the area to be bonded, and then covering a frame-shaped portion within a predetermined range from the outer periphery with photomasks 71 and 72, and then exposing or semi-exposing the intermediate portion.

Dry film resist has adhesiveness in an unexposed state, and has the property of curing by exposure to light, becoming non-adhesive and transitioning to a stable state in which the volume does not change over time.
When dry film resist is subjected to partial exposure, which involves reducing the amount of exposure by limiting the light transmittance of the photomask during exposure or shortening the exposure time, it becomes partially cured and reaches a semi-cured state. In this semi-cured state, the degree of tackiness and the change in volume over time are both smaller than in the uncured state, and the adhesive strength as an adhesive layer also decreases with the decrease in tackiness.

Dry film resist has an adhesive resist film formed by applying a resist liquid to the surface of a carrier film and drying it, and is supplied in a state in which a cover film is placed on the resist film. After removing the cover film, the dry film resist is placed so that the resist film contacts the surface of the installation target area. Then, after exposing the required areas through the carrier film to light to produce hardened areas, the carrier film is also peeled off and removed.

The adhesive layer 12 has a two-layer structure consisting of a first resist 12a and a second resist 12b, and each resist is a photosensitive dry film resist, but any resist other than a dry film resist may be used as long as it is in a sheet form and has an adhesive function. However, a photosensitive resist is preferable in terms of ease of handling, such as facilitating processing for adjusting from an uncured state to a semi-cured state or a cured state.

The conductive layer 13 is made of thin sheets 13a, 13b, 13c made of a metal suitable for electroforming, such as nickel.
3c are stacked three times to form a laminate.
The thickness of each of the sheets 13a, 13b, and 13c constituting the conductive layer 13 is set to become smaller with increasing distance from the adhesive layer 12. For example, the thicknesses of the sheets 13a, 13b, and 13c are set to become smaller with increasing distance from the adhesive layer 12, for example, 60 μm, 40 μm, 20 μm, and 30 μm from the side closer to the adhesive layer.
It is said to be μm.

These sheets 13a, 13b, and 13c are subjected to a predetermined surface treatment at the boundary surfaces of the sheets to promote separation so that each sheet can be peeled off from the mask side when removing the matrix after the mask is completed.

Although the conductive layer 13 has a laminated structure made of three sheets, the present invention is not limited to this, and may have a laminated structure of multiple sheets other than three, such as two sheets or four or more sheets. In addition, the conductive layer may be in the form of a single sheet that does not have a laminated structure.

The deposition mask 1 formed using the master mold 10 of this embodiment is configured to include a plurality of mask bodies 2 each having a large number of deposition through-holes 8 formed in a predetermined pattern, and a frame body 3 arranged around the mask bodies 2.

The mask body 2 is made of nickel, nickel alloys such as nickel-cobalt, or other electrodeposited metals, and is formed into a sheet shape by electroforming, and is configured to have a large number of independent deposition through holes 8 formed in a predetermined pattern to allow the deposition material to pass through.

The mask body 2 includes an internal pattern formation region 2a in which a large number of deposition through-holes 8 are provided, and an outer peripheral edge 2b which is integrally joined to the frame body 3 via a metal layer 7 formed by plating. In the pattern formation region 2a, the large number of deposition through-holes 8 form a matrix-like deposition pattern 9 in which a plurality of rows of through-hole groups arranged linearly in the front-rear direction are arranged in parallel in the left-right direction for forming a light-emitting layer.

The frame 3 is a rectangular frame-shaped plate that is thicker than the mask body 2, and is disposed surrounding the outside of the mask body 2 to reinforce the mask body 2, and is integrally connected to the mask body 2. In detail, the frame 3 is formed in a lattice shape overall, and the mask bodies 2 are located in the respective opening regions partitioned inside, and are integral with the frame 3 via the metal layer 7.

The frame 3 is made of a material with a low thermal expansion coefficient, such as Invar, which is a nickel-iron alloy, or Super Invar, which is a nickel-iron-cobalt alloy, etc. The frame 3 is connected and integrated with the outer periphery 2b of the pattern formation region 2a of the mask body 2 by a metal layer 7 formed by plating so that they do not separate from each other.

When an Invar material or a Super Invar material is used as the material of the frame body 3, the extremely small thermal expansion coefficient of the material can satisfactorily suppress dimensional changes in the mask body 2 due to the thermal influence in the deposition process. That is, even if the mask body 2 is made of, for example, nickel, which has a larger thermal expansion coefficient than that of general glass, which is the deposition substrate (not shown), there is no deviation between the through-hole positions relative to the substrate when the deposition mask 1 is aligned with the deposition substrate at room temperature and the deposition position of the deposition material during actual deposition due to the difference in thermal expansion coefficient caused by the high temperature during deposition, and the small thermal expansion coefficient of the frame body 3 that holds the mask body 2 effectively suppresses dimensional changes and shape changes caused by the expansion of the mask body 2 when the temperature rises, and the alignment accuracy at room temperature can be well maintained even when the temperature rises during deposition.

The frame 3 may be made of a material having a low thermal expansion coefficient similar to that of the glass substrate, such as glass or ceramic. In this case, at least the surface of the material is made conductive.

The deposition mask 1 is formed by forming a primary pattern resist 14 on the surface of a matrix 10 in correspondence with non-positioned portions of a primary electrodeposition layer 15, forming a primary electrodeposition layer 15 on the matrix 10 by electroforming an electrodeposited metal, forming a secondary pattern resist 16 covering a portion of the primary electrodeposition layer 15 corresponding to a pattern formation region 2a, and then arranging a frame 3 so as to surround the primary electrodeposition layer 15, and then plating a metal layer 7 by plating so as to cover the surface of the frame 3 and the surface of the outer periphery 2b of the primary electrodeposition layer 15.
The primary electrodeposition layer 15 and the frame 3 are integrally connected via the metal layer 7 so that they do not separate, and the integrated primary electrodeposition layer 15, frame 3 and metal layer 7 are then separated from the matrix 10 to produce the mold.

Once the metal layer 7 has been formed on the matrix 10 by plating (see FIG. 12C), the matrix 10 is separated and removed therefrom (see FIGS. 13 and 14). The matrix 10 is physically peeled off and removed from the deposition mask side by applying force, and more specifically, each layer constituting the matrix 10 is separated. That is, the base portion 11 and the conductive layer 13 are separated from the mask side in that order, and the sheets 13a, 13b, and 13c constituting the conductive layer 13 are separated one by one starting from the side furthest from the mask side.

The primary electrodeposition layer 15 is made of nickel or a nickel alloy such as nickel-cobalt that is suitable for electroforming, and is formed by electroforming in a portion of the matrix 10 where there is no primary pattern resist 14. In the deposition mask 1, the primary electrodeposition layer 15 is formed to constitute a mask body 2 that covers the surface of the deposition target substrate, except for deposition through holes 8 that correspond to deposition target portions of the deposition target substrate, such as a light-emitting layer.

The primary pattern resist 14 is made of an insulating material that is resistant to dissolution in an electrolyte used in electroforming of the primary electrodeposition layer 15, and is a pattern of the primary electrodeposition layer 15 that is set in advance on the matrix 10.
The insulating layer 14 is disposed in correspondence with the non-placed portions of the primary electrodeposition layer 15 and is removed after the primary electrodeposition layer 15 is formed (see FIGS. 9 and 10).

The primary pattern resist 14 is disposed on the mother mold 10 prior to the formation of the primary electrodeposition layer 15, and a photosensitive resist, for example, a negative type photosensitive dry film resist, is applied to the mother mold 1.
0 to a predetermined thickness, for example, about 20 μm, and with a photomask 41 of a predetermined pattern corresponding to the position of the mask body 2 of the deposition mask 1, i.e., the position of the primary electrodeposition layer 15, placed on top of it, the photomask 41 is hardened by exposure to ultraviolet light, and developed to remove the resist in the non-irradiated areas, and then formed into a shape corresponding to the non-positioned areas of the primary electrodeposition layer 15.

The secondary pattern resist 16 is made of an insulating material that is resistant to dissolution in the electrolytic solution used for plating the metal layer 7, and is disposed in a manner corresponding to a predetermined non-placement portion of the metal layer 7. The secondary pattern resist 16 is removed after the formation of the metal layer 7 and the separation of the matrix 10 (FIG. 11,
See Figures 12 and 14.

This secondary pattern resist 16 is formed by applying a photosensitive resist, for example, a negative type photosensitive dry film resist, to the matrix 10 and the primary electrodeposition layer 15 already disposed thereon, and forming a photomask 42 having a predetermined pattern corresponding to the positions of the metal layer 7 and the frame 3 of the deposition mask 1.
A series of steps of exposing the mask to ultraviolet light with the mask placed thereon is repeated once or a number of times until the required resist thickness is achieved, and then the mask is formed into a shape corresponding to the non-placement portions of the metal layer 7 (the pattern formation regions 2 a of the mask body 2 ) through processes such as development to remove the photosensitive material in the non-irradiated portions during the exposure.

In addition, the secondary pattern resist 16 (resist layer 18), the first resist 12a (another resist 64) and the second resist 12b (one resist 63) constituting the adhesive layer 12 are
) and the primary pattern resist 14 (resist layer 17), it is more preferable to use the same resist, since this makes it possible to make the specification conditions (such as dimensional variations due to exposure) the same.

The metal layer 7 is formed by plating and is made of nickel, a nickel-cobalt alloy, or the like, and is configured to be formed by plating on the mother mold 10, the already arranged primary electrodeposition layer 15, and the exposed portions of the frame 3 where the secondary pattern resist 16 is not provided.

The metal layer 7 bonds the outer periphery 2b of the pattern-forming region 2a of the mask body 2 to the frame 3. The metal layer 7 is laminated by plating on the upper surface of the mask body 2 relating to the outer periphery 2b of the pattern-forming region.
The upper surface of the mask body 2, the upper surface of the frame 3 and the side surface on the pattern formation region 2a side, and the gap between the mask body 2 and the frame 3, thereby integrally connecting the outer peripheral edge 2b of the pattern formation region 2a and the opening peripheral edge of the frame 3 so that they do not separate.

Next, a manufacturing process of the matrix according to this embodiment and a manufacturing process of a deposition mask using the matrix will be described.
First, the manufacturing process of the matrix 10 will be described.
A resist 61, for example an unexposed negative dry film, is arranged to a required thickness on the surface of a predetermined flat substrate 60 made of a metal suitable for electroforming (for example, stainless steel such as SUS304). A photomask 70 is placed over the resist except for a predetermined peripheral area of the resist.
After covering the resist 61 with the photomask 70, the outer peripheral portion of the resist 61 that is not covered with the photomask 70 is hardened by an exposure process, and the rest of the resist 61 is removed to form an outer frame resist 62 for electroforming (see FIG. 4).

Then, sheets are successively formed by electroforming in the inner portion surrounded by the outer frame resist 62 on the substrate 60, to obtain the conductive layer 13 consisting of three layers of sheets 13a, 13b, and 13c (see FIG. 5). Each of the sheets 13a, 13b, and 13c constituting the conductive layer 13 is formed by changing the thickness setting value so that each layer is thicker than the previous one. In addition, each of the sheets 13a, 13b, and 13c is subjected to a surface treatment each time a layer is formed to facilitate peeling when removing the matrix.

An adhesive layer 12 is formed on the obtained conductive layer 13. Specifically, a first resist 63, which is an unexposed negative dry film resist, is placed on the conductive layer 13, and a frame-shaped portion of a predetermined range from the outer periphery of the resist is covered with a photomask 71.
The intermediate portion that is not covered by the photomask 71 of No. 3 is exposed to light to harden the intermediate portion. In this manner, the second resist 12b is obtained from the first resist 63, in which the peripheral frame-shaped portion 12e is in an unexposed state and the intermediate portion 12f surrounded by the frame-shaped portion 12e is hardened (see FIG. 6).

On the second resist 12b with the hardened middle portion 12f, another resist 64, which is an unexposed negative dry film resist of the same thickness as the first resist 63, is placed, and a frame-shaped portion of a predetermined range from the outer periphery of the resist is covered with a photomask 72. Then, the middle portion of the other resist 64 that is not covered with the photomask 72 is semi-exposed with a smaller amount of exposure than the middle portion of the first resist 63, and the middle portion is semi-cured. In this way, the first resist 12a is obtained from the other resist 64, in which the outer periphery frame-shaped portion 12c is unexposed and the middle portion 12d surrounded by the frame-shaped portion 12c is semi-cured (see FIG. 7).

The half-exposure of the other resist 64 is performed so that the exposure amount is 1/2 to 1/50 of the exposure amount (integral light amount) during normal exposure. For example,
For a half exposure, the exposure amount is set to 1/20 ^{, 10 mJ/cm 2 .}

In addition, when forming the adhesive layer 12, it is possible to leave a carrier film covering the middle portion of one resist 63 or a cover film covering the middle portion of the other resist 64, so that a film is interposed between the middle portions of the first resist 12a and the second resist 12b. By preventing the middle portions of the resists from adhering to each other with the film, it is possible to further facilitate the separation operation starting from the resists of the adhesive layer 12.

The conductive layer 13 and the adhesive layer 12 are laminated together, and the adhesive layer 1 is then placed on the base portion 11, which is a metal plate.
2 and is then separated from the substrate 60 in a transfer step (see FIG. 8), whereby the matrix 10 is completed.

In this matrix 10, an adhesive layer 12 consisting of a first resist 12a and a second resist 12b is formed.
However, the intermediate portions 12d and 12e are surrounded by frame-like portions 12c and 12e in a predetermined range from the outer periphery of the intermediate portions 12d and 12e.
Since the adhesive layer 12 is in a stable state in which the volume change over time is reduced compared to the unexposed frame-shaped portions 12c and 12e at f, it is possible to prevent the influence of the change in volume of the adhesive layer 12 over time from reaching the primary electrodeposition layer 15 via the conductive layer 13 in the electroforming process using the matrix 10.
The adhesive layer 12 has a small adhesive force for bonding the base portion 11 and the conductive layer 13 at the intermediate portions 12d and 12f, so that the adhesive force for bonding the base portion 11 and the conductive layer 13 is small at the final step of separating the mother mold.
Therefore, the operation of separating the conductive layer 13 from the conductive layer 13 can be easily performed.

Next, a manufacturing process of the deposition mask will be described.
First, a resist layer 17 is provided on the matrix 10 in correspondence with the deposition through holes 8 of the mask body 2, i.e., the non-positioned portions of the primary electrodeposition layer 15, which are set in advance on the matrix 10 (see FIG. 9). Specifically, for example, a negative type photosensitive dry film resist is applied to the front surface side of the matrix 10, i.e., on the conductive layer 13, to a predetermined thickness (
For example, one or several sheets are laminated to a thickness of about 20 μm, and then the resist layer 17 is formed by thermocompression bonding (see FIG. 9A).

Then, a photomask (e.g., a glass mask) 41 having a predetermined pattern corresponding to the position of the primary electrodeposition layer 15, such as having light-transmitting holes 41a corresponding to the deposition holes 8, is adhered to the surface of the resist layer 17, and then exposure is performed by irradiating ultraviolet rays using an exposure device (ultraviolet ray irradiation device) (see Figures 9(B) and (C)).

In the exposure process for this resist layer 17, before exposure is performed with an exposure device, the master mold 10 on which the resist layer 17 has been formed is preheated, for example, using a hot plate or a preheating furnace, to a predetermined preheat temperature, for example, 27.0°C ± 0.3°C, which is preset as the temperature that can be reached inside the exposure device during the exposure process.

In addition, the photomask 41 to be placed on the surface of the resist layer 17 is also set in the exposure device, placed on a dummy mother mold (mother mold + resist layer), before exposure, and preheated to the same preheat temperature as in the case of the mother mold 10, for example 27.0°C ± 0.3°C, by dummy exposure, which sets the exposure device in the same operating state as in actual exposure.

In addition, for the stage on which the matrix 10 is placed in the exposure tool, either no exposure object such as a matrix is placed in the tool before the official exposure, or a dummy matrix is set on the stage and the exposure tool is put into the same operating state as in the actual exposure by a dummy exposure, which is preheated to the same preheat temperature as in the case of the matrix 10, for example 27.0°C±0.3°C.

In this way, the matrix 10, the photomask 41, and the inside (stage) of the exposure device are preheated to the same temperature, and then the photomask 41 is placed on the surface of the resist layer 17 on the matrix 10, and these are mounted on the stage of the exposure device to perform formal exposure.

The reason why the master mold 10, photomask 41, and the inside of the exposure apparatus (stage) are preheated to a temperature that will be reached during the exposure operation is as follows: the master mold 10, resist layer 17, and photomask 41 all have different thermal expansion coefficients. If these were placed inside the exposure apparatus and exposed at a temperature lower than the internal temperature when exposure is actually performed in the exposure apparatus, such as room temperature, the master mold 10 and other components would be heated and expand due to heat generated inside the exposure apparatus due to ultraviolet light irradiation, etc., and a shift in the relative positions of the master mold 10, resist layer 17, and photomask 41 would occur.

Such misalignment reduces the positional accuracy of the primary pattern resist 14 obtained after exposure relative to the matrix 10 and the accuracy of the shape of the primary pattern resist 14. If the primary pattern resist 14 has a reduced positional accuracy or a defective shape, this will affect the process of forming the primary electrodeposition layer 15 (mask body 2) by electroforming, and there is a risk that the mask body 2 cannot be formed with the accuracy as intended by the design.

In response to this, by preheating the master mold 10 (including the resist layer 17), photomask 41, and exposure device (stage) to a temperature that can be reached during the exposure operation, and then performing exposure using the exposure device, not only is there no new thermal expansion of the master mold 10 etc. due to a rise in temperature within the exposure device, but the temperature within the exposure device can be maintained at a stable level, and exposure proceeds without the master mold 10 etc. within the device being affected by temperature changes.

This improves the accuracy of the position and shape of the primary pattern resist 14 on the matrix 10 after exposure, and the primary electrodeposition layer 15 is formed based on the accuracy of the primary pattern resist 14.
The mask body 2 can also be formed stably and with high precision, and the accuracy of reproducing the deposition layer and the deposition accuracy of the mask body 2 can be improved. Note that the lower the preheating temperature, the more the thermal expansion can be suppressed, so it is preferable to use the standard temperature (23° C.) or even a lower temperature (for example, 0° C.).
Since heat is generated during exposure in the exposure device, there is a limit to how low the preheat temperature can be. If the main objective is to avoid the effects of thermal expansion due to the heat generated during exposure as described above, it is preferable to set the preheat temperature to the maximum temperature that will be reached inside the exposure device during exposure.

In addition, when taking into consideration the thermal expansion in each process after exposure, it is preferable to set the preheat temperature to the maximum temperature among the temperatures in the exposure device (exposure temperature), plating tank (plating temperature), and deposition device (deposition temperature).

After the exposure, processes such as development and drying are carried out to remove the resist from the masked unexposed (non-irradiated) parts of the matrix 10. In this way, a primary pattern resist 14 corresponding to the non-positioned parts of the primary electrodeposition layer 15 is obtained on the matrix 10 (see FIG. 10(A)).

Incidentally, such primary pattern resist 14 can also be formed by a lithography method using a photoresist or the like or by any other method, and the method of formation is not limited to the above.

The matrix 10 having the primary pattern resist 14 is placed in an electroforming tank prepared under predetermined conditions, and the primary pattern resist 14 of the matrix 10 is electroformed within the range of the thickness of the primary pattern resist 14.
A primary electrodeposition layer 15, which will become the mask body 2, is formed on the surface (exposed area) not covered with the mask, by electroforming a metal such as a nickel alloy, to a thickness of, for example, 12 μm (see FIG. 10B).

Thereafter, the primary pattern resist 14 is dissolved and removed to leave a predetermined deposition pattern 9
A primary electrodeposition layer 15 is obtained which will become the mask body 2 having a large number of independent deposition through holes 8 (see FIG. 10C).

After the primary electrodeposition layer 15 is obtained, a resist layer 18 is provided on the entire surface of the matrix 10 including the portion on which the primary electrodeposition layer 15 is to be formed. Specifically, for example, one or several sheets of negative-type photosensitive dry film resist are laminated on the surface side of the matrix 10 according to a predetermined thickness, and the resist layer 18 is formed by thermocompression bonding (see FIG. 11(A)).

11B, a photomask 42 having light-transmitting holes 42a corresponding to the pattern-forming regions 2a of the mask body 2 is attached to the surface of the resist layer 18, and then the resist layer 18 is exposed to ultraviolet light (see FIGS. 11B and 11C). As a result, the portions corresponding to the pattern-forming regions 2a become resist layers 18a that have been hardened by exposure, and the other portions become resist layers 18b that are not exposed.
Thereafter, a process is carried out to dissolve and remove the unexposed resist layer 18b that is exposed on the surface.
A secondary pattern resist 16 is formed to cover the pattern forming region 2a (see FIG. 12(A)).
.

After forming the secondary pattern resist 16 in this manner, the adhesive layer 19 is placed on the underside of the frame 3 that has already been formed through the frame formation process, and is aligned and placed at a predetermined location on the primary electrodeposition layer 15 (see FIG. 12(B)).

In this state, the frame 3 can be temporarily fixed on the primary electrodeposition layer 15 due to the adhesiveness of the adhesive layer 19 so that it does not move easily.
If necessary, a process of applying a load to the temporarily fixed frame body 3 from above to press the frame body 3 can be carried out to make the frame body 3 even less likely to separate from the primary electrodeposition layer 15.

Thereafter, a metal layer 7 is formed by plating with an electrodeposited metal on the upper surface of the primary electrodeposition layer 15 that is not covered with the secondary pattern resist 16 and is exposed on the surface relating to the outer periphery 2b of the pattern formation region 2a, on the primary electrodeposition layer 15a on the lower side of the frame 3 and on each exposed surface of the matrix 10 that is exposed on the side thereof, and on the surface of the frame 3 (see FIG. 12(C)). This metal layer 7 can connect the primary electrodeposition layer 15 and the frame 3 together so that they do not separate.

In this case, the thickness of the metal layer 7 on the surface of the frame 3 is formed to be thinner than the thickness of the upper surface of the primary electrodeposition layer 15 exposed on the surface relating to the outer periphery 2b of the pattern formation region 2a and the thickness of the metal layer 7 on the surface of the matrix 10 exposed on the surface between the primary electrodeposition layer 15 and the frame 3. This difference in thickness occurs only when the metal layer 7 is sequentially layered from the surfaces of the matrix 10 and the primary electrodeposition layer 15, and reaches the frame 3 beyond the height dimension of the adhesive layer 19, and then the frame 3 is completely covered with the matrix 10 and the primary electrodeposition layer 15.
This is because the metal layer 7 starts to be formed on the surface of the frame 3 .

Once the formation of the metal layer 7 is complete, in the final step, the master mold 10 is separated from the integrated primary electrodeposition layer 15, frame 3, and metal layer 7. This separation is performed starting from the base portion 11 of the master mold, and the base portion 11 is first peeled off from the conductive layer 13. In this case, the base portion 11 is peeled off starting from between the first resist 12a and the second resist 12b of the adhesive layer 12. Since the middle portion 12c of the first resist 12a of the adhesive layer 12 is in a semi-cured state and the middle portion 12d of the second resist 12b is in a cured state, the base portion 11 can be peeled off smoothly at this adhesive layer portion (
See Figure 13(A).
When the base portion 11 is peeled off, the remaining portion consisting of the primary electrodeposition layer 15 and the conductive layer 13 has a sufficient thickness so that the primary electrodeposition layer 15 is not adversely affected, such as being deformed.

After the base portion 11 (including the first resist 12a portion of the adhesive layer 12) is separated, the sheets constituting the conductive layer 13 are peeled off one by one from the side away from the primary electrodeposition layer 15 (FIG. 13).
(B), see Fig. 14 (A) and (B). Since the surface of each layer of the sheet is treated,
When a force is applied to peel them off, they can be easily separated.
a, 13b, and 13c become thinner as they approach the primary electrodeposition layer 15 etc., so that the load on the primary electrodeposition layer 15 etc. is small and the primary electrodeposition layer 15 can be separated without deforming it.

Even when the sheets 13a, 13b, and 13c constituting the conductive layer 13 are peeled off, the remaining sheets of the conductive layer 13 are integrally attached to the primary electrodeposition layer 15 to reinforce it, so that the primary electrodeposition layer 15 is not adversely affected, such as being deformed.

In addition, since the sheets 13a, 13b, and 13c constituting the conductive layer 13 become thinner as they approach the primary electrodeposition layer 15, etc., when the last sheet 13a of the conductive layer 13 is directly separated from the primary electrodeposition layer, etc., the force applied to the primary electrodeposition layer 15, etc. can be kept to a minimum, and the primary electrodeposition layer 15 can be separated without deforming it.

When all the sheets 13a, 13b, and 13c constituting the conductive layer 13 have been peeled off and the separation of the matrix 10 has been completed, the primary electrodeposition layer 15a present on the lower side of the frame 3 is removed together with the adhesive layer 19, and then the secondary pattern resist 16 is removed, thereby completing the manufacture of the deposition mask 1.
When the adhesive layer 19 remains on the lower side of the frame 3, it is removed when removing the secondary pattern resist 16. Moreover, the secondary pattern resist 16 may be removed before the matrix 10 is separated.

In this way, in the electroforming master mold according to this embodiment, the central portion of the adhesive layer 12 other than the frame-shaped portion within a predetermined range from the outer periphery is in a state in which volume change over time is unlikely to occur, and the structure of the adhesive layer 12 as a whole is stabilized. This makes it possible to stably fix and integrate the base portion 11 and the conductive layer 13 with an adhesive layer that has small volume change over time, and prevents the conductive layer 11 from changing in volume due to the change in the adhesive layer 12.
This can suppress the displacement of the conductive layer 13 and the positional deviation of the primary electrodeposition layer 15 formed on the conductive layer 13, thereby preventing a decrease in the accuracy of the mask body 2 formed using the matrix 10.

In addition, while a sufficient adhesive strength is ensured in a frame-shaped portion within a predetermined range from the outer periphery of the adhesive layer 12,
By suppressing the adhesive strength of the middle portion of the adhesive layer 12, the integration of the base portion 11 and the conductive layer 13 that form the master mold 10 during the electroforming process can be reliably maintained, while after electroforming is completed, the base portion 11 and the conductive layer 13 can be separated with less force starting from the position of the adhesive layer. After electroforming, the base portion 11 and the conductive layer 13 can be sequentially separated from the mask side, making it easy and efficient to separate and remove the master mold 10 from the mask. Furthermore, by reducing the force applied to the mask side when separating the master mold, adverse effects such as deformation of the mask body 2 can be suppressed.

The electroforming matrix according to the embodiment is configured as a matrix for forming the deposition mask 1 having a structure in which the mask body 2 and the frame 3 are integrated with the metal layer 7, among deposition masks for organic EL elements. However, the present invention is not limited to this, and may be applied to metal masks having other structures, such as a mask having only the mask body without the frame, a mask having the mask body and the frame but integrated by adhesion, a mask having the mask body and the frame but integrated by adhesion, or a mask having the mask body and the frame but integrated by adhesion.
The mold may be used to form a mask having an integrated structure bonded via a bonding agent. The mold may also be used to form a printing mask, a mask for mounting solder balls, or the like, other than a deposition mask.

Second Embodiment of the Invention
In the manufacturing method of the electroforming mold according to the first embodiment, the conductive layer 1 is formed in the adhesive layer forming step.
The intermediate portion of one resist 63 placed on the first resist 63 is exposed to light, and the intermediate portion of another resist 64 placed on the first resist 63 is partially exposed to light, to obtain a second resist 12b in which the intermediate portion 12f is in a cured state with no adhesion and no change in volume over time, and a first resist 12d in which the intermediate portion 12d is in a semi-cured state with less adhesion and less change in volume over time than the unexposed portion.
2a, and the first resist 12a and the second resist 12b are bonded to an adhesive layer 12
However, the present embodiment is not limited to this, and as a second embodiment, as shown in FIG.
In the adhesive layer formation process, exposure can be performed on both the middle portion of one resist 63 and the middle portion of the other resist 64, so that the middle portions 12d, 12f of both the first resist 12a and the second resist 12b constituting the adhesive layer 12 are hardened so that they are not sticky and their volume does not change over time.

In this case, as in the above embodiment, the central portion of the adhesive layer 12 other than the frame-shaped portion within a predetermined range from the outer periphery can be made to be in a state in which the volume is unlikely to change over time. In the state of the mother mold 10 in which the base portion 11 and the conductive layer 13 are bonded and integrated with each other by the adhesive layer 12, the conductive layer 1
3 and the positional deviation of the primary electrodeposition layer 15 (mask body 2) formed on this conductive layer 13 can be suppressed, and a highly accurate mask can be formed using the master mold 10. Also, a frame-shaped portion within a predetermined range from the outer periphery of the adhesive layer 12 is left unexposed to maintain adhesion and ensure sufficient adhesive strength, while the adhesive strength of the intermediate portion is suppressed to reduce adhesive strength, so that the integration of the base portion 11 and conductive layer 13 constituting the master mold 10 is reliably maintained by the adhesive layer 12 in the electroforming process, while the base portion 11 and conductive layer 13 can be separated with a small force at the adhesive layer position after electroforming is completed, and the master mold 10 can be easily removed from the mask.
Therefore, separation and removal of the particles can be easily and efficiently performed.

In addition, the exposure of the intermediate portions of both resists 63 and 64 in the adhesive layer forming process is not limited to a method of applying an exposure amount sufficient to completely harden the resists. In addition, as shown in FIG. 16, the intermediate portion of one resist 63 and the intermediate portion of the other resist 64 may be exposed to light.
It is also possible to perform half-exposure with a reduced amount of exposure on both the first resist 12a and the second resist 12b constituting the adhesive layer 12, so that the intermediate portions 12d, 12f are in a semi-cured state having smaller adhesion and smaller change in volume over time than the unexposed frame-shaped portions 12c, 12e on the outside.

Third embodiment of the present invention
In the manufacturing of the electroforming mold according to the first embodiment, in the adhesive layer formation process, another resist 64 is placed on the first resist 63 after the middle portion has been exposed to light, and the middle portion of this other resist 64 is partially exposed to light to obtain a first resist 12a in which the middle portion 12d is in a semi-cured state with less adhesiveness and less change in volume over time than the unexposed frame-shaped portion 12c. However, without being limited to this, as a third embodiment, as shown in Figure 17, it is also possible to place another resist 64, which is an unexposed negative dry film resist, on the first resist 63 after the middle portion has been exposed to light, and then not expose the other resist 64 to light to obtain a first resist 12a that remains entirely unexposed.

In this case, the second resist 12b of the adhesive layer 12 has a hardened state in which the intermediate portion 12f does not have adhesion and does not change in volume over time, so that the adhesive layer as a whole is in a state in which the central portion is unlikely to change in volume over time, as in the above embodiment, and in the state of the master mold 10 in which the base portion 11 and the conductive layer 13 are bonded and integrated with the adhesive layer 12, the displacement of the conductive layer 13 due to the volume change of the adhesive layer 12 and the positional deviation of the primary electrodeposition layer 15 (mask body 2) formed on the conductive layer 13 are suppressed.
The adhesive strength integrating the base portion 11 and the conductive layer 13 is smaller than that of the outer frame-shaped portion, which promotes easy and rapid separation of the base portion 11 and the conductive layer 13 starting from the adhesive layer 12 after electroforming is completed.

The combination of the second resist 12b, which has been exposed to light and is in a cured state in which the middle portion 12f does not have adhesiveness and does not change in volume over time, and the first resist 12a, which is entirely unexposed, as the adhesive layer 12 can be made by making the resists 12a and 12b thin and of the same thickness (for example, a thickness of several tens of μm) as in the first embodiment as shown in FIG. 17, or by combining the second resist 12b, whose middle portion 12f is in a cured state, with the first resist 12a as shown in FIG.
Alternatively, as shown in Fig. 19, the first resist 12a and the second resist 12b may both be combined to be thicker than the thin resist 12a (for example, several tens of µm thick). However, it is more preferable to make each resist 12a and 12b thinner, since even if a change in volume occurs over time, the amount of change can be relatively small and the effect on the conductive layer, etc. can be suppressed.

(Fourth embodiment of the present invention)
In the manufacturing method of the electroforming mold according to the first embodiment, the conductive layer 1 is formed in the adhesive layer forming step.
In the fourth embodiment, the first resist 63 placed on the conductive layer 13 in the adhesive layer forming step is exposed to light at an intermediate portion thereof, and then the other resist 64 placed on the first resist 63 is partially exposed to light at an intermediate portion thereof to obtain a second resist 12b having an intermediate portion 12f that has been hardened by exposure, and a first resist 12a having an intermediate portion 12d that has been semi-hardened by half-exposure. However, the present invention is not limited to this. As a fourth embodiment, as shown in FIG. 20 and FIG. 21, the first resist 63 placed on the conductive layer 13 in the adhesive layer forming step is not exposed to light and is left in an unexposed state, while the other resist 64 placed on the first resist 63 is exposed or partially exposed at an intermediate portion thereof, and the first resist 12a having an intermediate portion 12d that has been hardened or semi-hardened by the exposure step is obtained.
Alternatively, the resist 12a may be formed by exposing the first resist 12a to light and the second resist 12b may be formed by leaving the second resist 12b entirely unexposed.

In this case, the first resist 12a of the adhesive layer 12 has a middle portion 12d in a cured or semi-cured state in which the adhesiveness and the change in volume over time are reduced. As a result, as in the above embodiment, the adhesive layer as a whole is in a state in which the volume of the middle portion is unlikely to change over time. In this case, in the state of the mother mold 10 in which the base portion 11 and the conductive layer 13 are bonded and integrated by the adhesive layer 12,
This suppresses the displacement of the conductive layer 13 due to the volume change of the adhesive layer 12, and the positional deviation of the primary electrodeposition layer 15 (mask body 2) formed on the conductive layer 13. In addition, the adhesive force that integrates the base portion 11 and the conductive layer 13 in the middle part of the adhesive layer 12 is smaller than that in the outer frame-shaped part, which promotes easy and quick separation of the base portion 11 and the conductive layer 13 starting from the adhesive layer 12 after completion of electroforming.

In the manufacturing of the electroforming mother mold according to each of the first to fourth embodiments, in the adhesive layer forming step, the second resist 12b and the first resist 12c are exposed to light in a frame-shaped portion within a predetermined range from the outer periphery of the first resist 63 and the other resist 64.
In the embodiment, the frame-shaped portions of the resist 63 are exposed to light or partially exposed to light, and the frame-shaped portions 1 and 2a are maintained in an uncured state having adhesiveness.
It is also possible to obtain a second resist 12b in which the portion 2e is in a hardened or semi-hardened state, or to expose or semi-expose the frame-shaped portion of another resist 64 to light so as to obtain a first resist 12a in which the frame-shaped portion 12c is in a hardened or semi-hardened state.

In this case, one resist 63 is exposed or partially exposed to a frame-shaped portion of the other resist 63.
The intermediate portion of the other resist 64 may be exposed or semi-exposed, or may not be exposed, and the intermediate portion 12f of the resulting second resist 12b may be in a cured, semi-cured, or uncured state. On the other hand, when the frame-shaped portion of the other resist 64 is exposed, it is preferable that the intermediate portion of the other resist 64 is semi-exposed or not exposed, and the intermediate portion 12d of the resulting first resist 12a is in a semi-cured or uncured state. When the frame-shaped portion of the other resist 64 is semi-exposed, the intermediate portion of the other resist 64 may be exposed or semi-exposed, or may not be exposed, and the intermediate portion 12d of the resulting first resist 12a is in a semi-cured or uncured state.
It may be in a cured, semi-cured, or uncured state.

In addition, the frame-shaped portion 12c of the first resist 12a and the frame-shaped portion 12b of the second resist 12b are
There is no particular need to make the properties of frame-shaped portion 12c of first resist 12a and frame-shaped portion 12e of second resist 12b identical; for example, when frame-shaped portion 12c of first resist 12a is in a cured state, frame-shaped portion 12e of second resist 12b can be in a semi-cured or uncured state.

The electroforming matrix and the method for manufacturing the same according to the present invention will now be described.
In the case of forming a mask by electroforming, when separating the mask from the matrix, the matrix is usually thicker than the mask. Therefore, when the matrix is deformed in a direction away from the electrodeposit layer that becomes the mask due to the force applied for separation, excessive force is applied to the electrodeposit layer, causing permanent deformation of part of it and potentially reducing accuracy.

For this reason, a proposal has been made in recent years to form a master mold used in electroforming into a layered structure in which each layer of the master mold is separated in sequence from the side furthest from the electrodeposit layer that serves as a mask, thereby preventing the electrodeposit layer from being deformed by excessive force.

In such a laminated mold, each layer of the mold must be kept bonded together until the mask and the mold are separated after the mask is formed. However, if a general adhesive is used to bond each layer of the mold, it is difficult to control the thickness of the adhesive layer uniformly, and the flatness of the primary electrodeposition layer (mask) formed on the mold cannot be ensured, which may adversely affect the accuracy of the mask. For this reason, it has been proposed to use a dry film resist that has a certain adhesive strength when unexposed as the adhesive.

Dry film resist is a sheet with a uniform thickness, and when used for adhesion, the flatness of the primary electrodeposition layer can be ensured without any problems. However, since the dry film resist is used for adhesion without being exposed to light, and the dry film resist is not in a stable cured state after exposure between each layer of the matrix, if it is left in the form of the matrix for a certain period of time, it may undergo volumetric changes such as shrinkage due to the outflow of some components such as volatile matter, which may have adverse effects such as misalignment on the primary electrodeposition layer (mask) formed on the matrix.

The electroforming master mold disclosed in the present invention is used for manufacturing a mask having a large number of through holes by electroforming, and includes a plate-shaped base portion having at least one flat surface, a sheet-shaped adhesive layer disposed on the flat surface of the base portion, and a sheet-shaped conductive layer having a single or multiple laminated structure and having electrical conductivity, which is attached to the base portion via the adhesive layer, and the intermediate portion of the adhesive layer, which is surrounded by a frame-shaped portion within a predetermined range from the outer periphery of the adhesive layer, has a smaller change in volume over time than the frame-shaped portion, and has a smaller adhesive force bonding the base portion and the conductive layer.

In this way, according to the disclosure of the present invention, the adhesive layer is designed to be in a state in which the volume of the central portion other than the frame-shaped portion within a predetermined range from the outer periphery is less likely to change over time, and while maintaining a state in which adhesive force is generated at least in the frame-shaped portion, the structure of the adhesive layer as a whole is stabilized. This makes it possible to stably fix and integrate the base portion and the conductive layer with an adhesive layer that has small volumetric changes over time, suppressing displacement of the conductive layer due to volumetric changes in the adhesive layer and misalignment of the electrochemical layer formed on this conductive layer, and preventing a decrease in the accuracy of the mask formed using the master mold.

In addition, by ensuring sufficient adhesive strength in a frame-shaped portion within a specified range from the outer edge of the adhesive layer while suppressing the adhesive strength in the middle portion of the adhesive layer, the integration of the base portion and conductive layer that form the master mold in the electroforming process is reliably maintained, and the base portion and conductive layer can be separated with less force at the adhesive layer position after electroforming is completed. After electroforming, the base portion and conductive layer can be separated sequentially from the mask side, making it easy and efficient to separate and remove the master mold from the mask, and reducing the force applied to the mask side when separating the master mold, suppressing adverse effects such as deformation of the mask body.

In addition, the electroforming master mold disclosed in the present invention may, as necessary, comprise a first resist in which the adhesive layer is disposed in contact with the base portion and in which at least a frame-shaped portion within a predetermined range from the outer periphery is in an uncured state and has adhesive properties, and a second resist in which the adhesive layer is disposed in contact with the conductive layer and in which at least a frame-shaped portion within a predetermined range from the outer periphery is in an uncured state and has adhesive properties, and an intermediate portion surrounded by the frame-shaped portion in at least one of the first resist and the second resist is in a cured state that does not have adhesive properties and does not change in volume over time.

In this way, according to the disclosure of the present invention, by curing the middle part of at least one of the two layers of resist that make up the adhesive layer and bringing the middle part of the adhesive layer closer to a stable state in which volumetric changes over time are unlikely to occur, even after time has passed since the base part and the conductive layer are fixed and integrated by the adhesive layer, volumetric changes in the adhesive layer are suppressed, preventing displacement of the conductive layer and the associated positional shift of the electrodeposition layer on the conductive layer, and enabling the manufacture of a high-precision mask. In addition, by curing the middle part of at least one of the two layers of resist that make up the adhesive layer and bringing it into a state in which adhesive force is not exerted, separation of the base part and the conductive layer after electroforming is completed can be performed with less force starting from the adhesive layer, and separation and removal of the mother mold from the mask can be smoothly carried out.

In addition, the electroforming master mold disclosed in the present invention may, as necessary, comprise a first resist disposed in contact with the base portion, the adhesive layer having a frame-shaped portion in at least a predetermined range from the outer periphery and in an uncured state with adhesiveness, and a second resist disposed in contact with the conductive layer, the frame-shaped portion in at least a predetermined range from the outer periphery and in an uncured state with adhesiveness, and an intermediate portion surrounded by the frame-shaped portion in at least one of the first resist and the second resist is in a semi-cured state with less adhesiveness and less change in volume over time than the frame-shaped portion.

As described above, according to the disclosure of the present invention, by making the middle part of at least one of the two layers of resist that make up the adhesive layer semi-cured and making the middle part of the adhesive layer in a state in which volumetric changes over time are unlikely to occur, even if time has passed since the base part and the conductive layer are fixed and integrated by the adhesive layer, volumetric changes in the adhesive layer are suppressed, preventing displacement of the conductive layer and the associated positional shift of the electrodeposition layer on the conductive layer, and enabling the manufacture of a high-precision mask. In addition, by making the middle part of at least one of the two layers of resist that make up the adhesive layer semi-cured and making the adhesive force weaker, the base part and the conductive layer can be separated from each other with less force after electroforming is completed, starting from the adhesive layer, and the mother mold can be smoothly separated and removed from the mask.

In addition, in the electroforming master mold disclosed in the present invention, if necessary, the first resist in the adhesive layer has the frame-shaped portion in an uncured state and the middle portion surrounded by the frame-shaped portion in a semi-cured state, and the second resist in the adhesive layer has the frame-shaped portion in an uncured state and the middle portion surrounded by the frame-shaped portion in a cured state.

In this way, according to the disclosure of the present invention, the middle part of the first resist of the two layers of resist that make up the adhesive layer is in a semi-cured state, while the middle part of the second resist is in a cured state, and the middle part of the adhesive layer is in a stable state in which the volume is unlikely to change over time. This makes it possible to appropriately suppress volume changes in the adhesive layer even after time has passed since the base part and the conductive layer are fixed and integrated by the adhesive layer, and prevents the conductive layer and the electrodeposition layer thereon from shifting, resulting in a highly accurate mask. In addition, since the middle part of the two layers of resist that make up the adhesive layer is in a state in which almost no adhesive force is exerted, the base part and the conductive layer can be separated from each other starting from the adhesive layer after electroforming is completed, and the efficiency of the work of separating the mask and the mother mold can be greatly improved.

The manufacturing method of an electroforming mother mold disclosed in the present invention is used for manufacturing a mask having a large number of through holes by electroforming, and includes a conductive layer forming step of forming one or more sheet-like conductive layers at predetermined positions on a predetermined flat metal substrate, an adhesive layer forming step of forming an adhesive layer having adhesive properties on the conductive layer, and a transfer step of attaching the formed conductive layer and adhesive layer to the flat surface of a plate-shaped base portion by the adhesive force of the adhesive layer and separating them from the substrate, and in the adhesive layer forming step, an intermediate portion of the adhesive layer surrounded by a frame-shaped portion within a predetermined range from the outer periphery of the adhesive layer is formed so that the volume change over time is smaller than that of the frame-shaped portion, and the adhesive force bonding the base portion and the conductive layer is smaller.

In this way, according to the disclosure of the present invention, a conductive layer is formed on a metal substrate, an adhesive layer is formed on the conductive layer, and the integrated conductive layer and adhesive layer are attached to a base portion by the adhesive strength of the adhesive layer, and the conductive layer and adhesive layer are separated from the substrate to manufacture a master mold consisting of the conductive layer, adhesive layer, and base portion. In this process, the adhesive layer is formed so that the intermediate portion of the adhesive layer other than the frame-shaped portion within a predetermined range from the outer periphery is unlikely to change in volume over time and has a small adhesive strength. This makes it possible to stably fix and integrate the base portion and the conductive layer with an adhesive layer that has a small volume change over time, suppressing displacement of the conductive layer due to volume change in the adhesive layer and positional deviation of the electrodeposition layer formed on the conductive layer, and preventing a decrease in accuracy of the mask formed using the manufactured master mold.

In addition, by ensuring adhesive strength in a frame-shaped portion within a specified range from the outer edge of the adhesive layer while suppressing adhesive strength in the middle portion of the adhesive layer, the integration of the base portion and conductive layer constituting the matrix is reliably maintained during the electroforming process using the manufactured matrix, and the base portion and conductive layer can be easily separated with less force at the adhesive layer position after electroforming is completed. This allows for efficient separation and removal of the matrix, which is carried out by sequentially separating the base portion and conductive layer from the mask side after electroforming, while also reducing the force applied to the mask side when separating the matrix, thereby suppressing adverse effects such as deformation of the mask body.

In addition, in the manufacturing method of the electroforming mold disclosed in the present invention, if necessary, in the adhesive layer forming step, a first resist, which is an unexposed negative dry film resist, is placed on the conductive layer, and a frame-shaped portion within a predetermined range from the outer periphery of the first resist is not exposed and remains unexposed, while a middle portion of the first resist surrounded by the frame-shaped portion is exposed to light to harden the middle portion, and another resist, which is an unexposed negative dry film resist, is placed on the first resist whose middle portion has been hardened, and a frame-shaped portion within a predetermined range from the outer periphery of the other resist is not exposed and remains unexposed, while a half-exposure is performed on the middle portion of the other resist surrounded by the frame-shaped portion, with the amount of exposure being smaller than that of the middle portion of the first resist, and the first resist and the other resist form the adhesive layer.

In this way, according to the disclosure of the present invention, in the adhesive layer forming process, one resist, which is a dry film resist forming an adhesive layer, and another resist are laminated, and for the one resist placed on the conductive layer, a frame-shaped portion within a predetermined range from its outer periphery is left unexposed, while the middle portion is hardened by exposure, and for the other resist placed on the one resist, a frame-shaped portion within a predetermined range from its outer periphery is left unexposed, while the middle portion is subjected to half-exposure with a small amount of exposure, so that the middle portion of the formed adhesive layer is in a stable state in which the volume is unlikely to change over time. Even if time has passed since the integration of the base portion and the conductive layer by the adhesive layer, the volume change in the adhesive layer can be appropriately suppressed, and the conductive layer can be prevented from being affected, and a highly accurate mask can be electroformed with the manufactured mother mold. In addition, by obtaining a state in which almost no adhesive force is exerted in the middle portion of the adhesive layer, the work of separating the formed mask and the mother mold can be efficiently carried out after the manufactured mother mold is used for electroforming.

1. Deposition mask (metal mask)
2 Mask body 2a Pattern formation region 2b Outer periphery 3 Frame 7 Metal layer 8 Vapor deposition through hole (through hole)
9. Deposition pattern (pattern)
REFERENCE SIGNS LIST 10 master mold 11 base portion 12 adhesive layer 12a first resist 12b second resist 12c, 12e frame-shaped portion 12d, 12f middle portion 13 conductive layer 13a sheet 13b sheet 13c sheet 14 primary pattern resist 15, 15a primary electrodeposition layer 16 secondary pattern resist 17 resist layer 18 resist layer 18a, 18b resist layer 19 adhesive layer 41 photomask 41a light-transmitting hole 42 photomask 42a light-transmitting hole 60 substrate 61 resist 62 outer frame resist 63, 64 resist 70 photomask 71, 72 photomask

Claims (9)

A method for manufacturing a metal mask including a mask body having a large number of through holes and a frame for reinforcing the mask body, comprising:
a mask body forming step of forming the mask body by electroforming using a matrix having a laminated structure;
a joining step of joining the mask body and the frame body,
the mask body forming step includes a resist layer forming step of forming a resist layer on a matrix and an exposure step of exposing the resist layer to light,
The mask body forming step includes a preheating step of preheating to a predetermined preheating temperature before the exposure step ,
the mother die includes a plate-shaped base portion, a sheet-shaped adhesive layer disposed on the base portion, and a conductive layer adhered to the base portion via the adhesive layer;
the adhesive layer has a property of being tacky in an uncured state, but transitioning to a state in which it is no longer tacky and in which its volume does not change over time as curing progresses;
a middle portion of the adhesive layer surrounded by a frame-shaped portion that is in an uncured state and extends from an outer periphery of the adhesive layer to a predetermined area, the middle portion being in a predetermined cured state with a smaller degree of change in volume over time than the frame-shaped portion. the adhesive layer of the matrix is a dry film resist arranged in two layers, and at least a frame-shaped portion within a predetermined range from an outer periphery is in the uncured state;
2. The method for manufacturing a metal mask according to claim 1, wherein the intermediate portion of at least one of the two layers of dry film resist constituting the adhesive layer is in a semi-cured state in which the adhesiveness is less than that of the frame-shaped portion and the degree of change in volume over time is small, or in a cured state in which the adhesiveness is not sufficient and the volume does not change over time. 3. The method for manufacturing a metal mask according to claim 1, further comprising a matrix preheating step of preheating the matrix to a predetermined preheating temperature prior to the exposure step. In the exposure step, exposure is performed by an exposure device,
4. The method for manufacturing a metal mask according to claim 3, further comprising an exposure device preheating step of preheating the inside of the exposure device to a predetermined preheat temperature before the exposure step. In the exposure step, exposure is performed using a photomask having a predetermined pattern corresponding to the mask body,
5. The method for producing a metal mask according to claim 4 , further comprising a photomask preheating step of preheating the photomask to a predetermined preheating temperature before the exposure step. The method for manufacturing a metal mask according to claim 5, characterized in that the master mold, the inside of the exposure device, and the photomask are preheated to the same temperature. The method for manufacturing a metal mask according to claim 6, characterized in that the maximum temperature reached within the exposure device is set to a preheat temperature. the mask body forming step further includes a primary pattern resist forming step of forming a primary pattern resist by removing an unexposed portion of the resist after the exposure step, and a primary electrodeposition layer forming step of forming a primary electrodeposition layer by electroforming on a surface of the mother mold that is not covered with the primary pattern resist,
8. The method for manufacturing a metal mask according to claim 3, wherein the preheating temperature is set to the maximum temperature among the exposure temperature in the exposure step, the electroforming temperature in the primary electrodeposition layer formation step, and the deposition temperature in the deposition step using a metal mask. A metal mask including a mask body having a large number of through holes and a frame for reinforcing the mask body,
the mask body is a metal plate-like body formed by electroforming in an exposed area of a matrix having a pattern resist;
the mother die has a laminated structure including a plate-shaped base portion, a sheet-shaped adhesive layer disposed on the base portion, and a conductive layer adhered to the base portion via the adhesive layer;
the adhesive layer has a property of being tacky in an uncured state, but transitioning to a state in which it is no longer tacky and in which its volume does not change over time as curing progresses;
an intermediate portion of the adhesive layer, which is surrounded by a frame-shaped portion that is in an uncured state and extends from an outer periphery of the adhesive layer, is in a predetermined cured state in which the degree of change in volume over time is smaller than that of the frame-shaped portion;
The metal mask according to claim 1, wherein the pattern resist is formed by exposing the resist layer to light and curing the resist layer in a state in which the mother mold, on which an unexposed resist layer has been formed, is preheated to a predetermined preheating temperature.