JP2004110016A - Method for manufacturing pattern forming mold - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple method of manufacturing a pattern forming mold, whose film thickness precision and film thickness controllability are high, whose selection range of an exposure light source is large, whose exposure time is short, whose productivity and pattern precision are high and by which the pattern forming mold formed of metal and resin is manufactured from a high aspect pattern. <P>SOLUTION: The method has: a first process for applying a radiation sensitive negative resist composition including epoxy resin shown by a general formula (1), radiation sensitive cationic polymerization initiator and solvent dissolving epoxy resin to a substrate; a second process for obtaining a resist film by drying the substrate to which the radiation sensitive negative resist composition is applied; and a third process for selectively exposing, by active energy rays, the obtained resist film by adjusting it to a desired pattern. The method also has: a fourth process for improving contrast by thermally treating the exposed resist film; a fifth process for developing the resist film after the thermal treatment and dissolving and removing a resist material in a non-exposed region; and a sixth process for installing the other material in a recessed part of the pattern layer, forming a second pattern layer, separating the second pattern layer for making the pattern forming mold. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a method for manufacturing a pattern forming die, which can be used, for example, in a photolithography step in a LIGA process, and in particular, can accurately and easily form a high-aspect pattern (a pattern having a high aspect ratio). The present invention relates to a method for manufacturing a pattern forming die that can be suitably used as a technology that can be manufactured at a high speed.

試 み Attempts have been made to use the LIGA process as a technique for manufacturing fine parts. The LIGA process enables the mass production of fine parts by forming a resist pattern similar to the desired part in the lithography process, creating a metal pattern in the electroforming process, and further using the metal pattern and a resin molding process. It is a technology to do. The LIGA process is described in detail in Chapter 1 of "LIGA Process" (Nikkan Kogyo Shimbun), and the elemental technology of the process is described in Chapter 2 of the book. In the lithography process of the LIGA process, the active energy rays in the lithography process are generally radiated due to the limitation of processing a very thick resist film generally having a thickness of more than 50 μm or even 100 μm and performing high aspect processing. X-rays obtained from light or the like are used.

Ｘ X-rays obtained from this radiation are used because they have high transparency to the resist material and high linearity, so that a high aspect pattern is easily obtained. Generally, PMMA (polymethyl methacrylate) is used as the resist material. On the other hand, as for a printed circuit board, an attempt to apply a negative resist, SU-8 (trade name), which is a resist material, to a LIGA process has been reported (see Patent Document 1). SU-8 is a cationic photopolymerizable curing composition composed of an epoxy resin and a radiation-sensitive cationic polymerization initiator, but has a small curing shrinkage that occurs during the reaction compared to a photoradical polymerizable curing composition using acrylate or the like. Is known and is suitable for processing a very thick film as in the LIGA process.

However, the method of applying PMMA involves a very complicated process due to poor film thickness accuracy because a methyl methacrylate monomer is polymerized on a substrate by a polymerization reaction (see Non-Patent Document 1 and the like). Further, in order to process PMMA having a large film thickness, synchrotron radiation capable of obtaining X-rays with extremely high intensity is used, but the processing time is extremely long and is not practical. Furthermore, PMMA has a problem that it is not sensitive to a high-pressure mercury lamp which is a light source having high versatility. Synchrotron radiation is disadvantageous as a light source because it requires a large-scale facility, although it has the advantage of very high pattern accuracy.

SU-8 (trade name) shows very good sensitivity and patterning property for a high-pressure mercury lamp, but has an aromatic ring in the skeleton of the novolak-type epoxy resin used for the material, so that Deep having a wavelength of 300 nm or less is used. There is a problem in that it has strong absorption in the UV region and exposure is restricted. Recent semiconductor microfabrication has demonstrated that shortening the exposure wavelength is effective for improving the pattern accuracy in the UV region. Therefore, the inability to use the Deep @ UV region is disadvantageous. Furthermore, it is necessary to select a cation initiator that matches the absorption (transparency) of the resin. However, since most of the cation initiators on the market match the absorption range of the novolak type epoxy resin, the matching initiator is There is also a problem that the range of choice is small.

On the other hand, as an aliphatic epoxy resin having no aromatic ring, for example, glycidyl (meth) acrylate, CYCLOMER A200, CYCLOMER M100 [both A200 and M100 are manufactured by Daicel Chemical Industries, Ltd .; having an alicyclic epoxy group (meth) Acrylate] and Celloxide 2000 (（1-vinyl-3,4-epoxycyclohexane manufactured by Daicel Chemical Industries, Ltd.) are marketed as monomers, and an epoxy resin can be synthesized from these monomers by a method such as radical polymerization.

However, in the case of (meth) acrylates such as glycidyl (meth) acrylate, CYCLOMER @ A200, and CYCLOMER @ M100, the (meth) acrylate ester skeleton of the main chain skeleton has high energy activity such as electron beam, Deep @ UV, and X-ray. It is known to have relatively high sensitivity to radiation, in which case side reactions other than the polymerization reaction due to the desired epoxy group occur in the main chain where the physical properties are most affected, so patterning, exposure sensitivity, curing It is not preferable because physical properties and the like vary or have an adverse effect. In addition, celloxide 2000 having no (meth) acryl skeleton is concerned about its toxicity, and there is a problem that strict management is required for use.

Japanese Patent Publication No. 7-78628 J. Mohr, W. Ehrfeld and D. Meunchmeryer: J. Vac. Sci. Technol., B6, 2264 (1988)

In view of such circumstances, the present invention can apply a resist composition by a simple method such as spin coating and a high film thickness accuracy and a high film thickness controllability, and has a large desired pattern accuracy and a wide selection range of an exposure light source. It is an object of the present invention to provide a method of manufacturing a pattern forming die for manufacturing a pattern forming die made of a metal, a resin, or the like from a high aspect pattern having a short time, high productivity, and high pattern accuracy.

The present inventor has conducted various studies to solve the above-mentioned problems, and as a result, when a specific aliphatic epoxy resin having no (meth) acryl skeleton is used for pattern formation, particularly in combination with a predetermined initiator, The resist composition can be applied by a simple method such as spin coating and high film thickness accuracy and high film thickness controllability, the desired pattern accuracy and the selection range of the exposure light source are large, the exposure time is short, and the productivity is high. The present inventors have found that a mold for pattern forming of metal, resin, and the like can be manufactured from a high-accuracy high-aspect pattern, and have completed the present invention.

According to a first aspect of the present invention, there is provided a radiation-sensitive negative resist composition comprising an epoxy resin represented by the general formula (1), a radiation-sensitive cationic polymerization initiator, and a solvent for dissolving the epoxy resin. A first step of coating the substrate with the radiation-sensitive negative resist composition, and a second step of obtaining a resist film by drying the substrate coated with the radiation-sensitive negative resist composition. A third step of selectively exposing the resist film in accordance with the above, a fourth step of improving the contrast by heat-treating the exposed resist film, and developing the unexposed resist material by developing the resist film after the heat treatment. A fifth step of obtaining a pattern layer by dissolving and removing, and providing another material in at least a concave portion of the pattern layer to form a second pattern layer; separating the second pattern layer to form a second pattern layer; In the manufacturing method of the pattern mold, characterized by having a sixth step of the over down mold.

(Wherein, R ¹ is k organic compound residues having active hydrogen (k is an integer of 1 to 100), n ₁ , n ₂ ... _Nk are 0 or an integer of 1 to 100. , The sum of which is 1 to 100, and A is the same or different, and is an oxycyclohexane skeleton represented by the following formula (2).)

(In the formula, X represents any of the following formulas (3) to (5), but includes at least two formulas (3) in one molecule.)

(In the formula, R ² is a hydrogen atom, an alkyl group, or an acyl group. The alkyl group and the acyl group preferably have 1 to 20 carbon atoms.)

A second aspect of the present invention is the method for manufacturing a pattern forming die according to the first aspect, wherein the second pattern layer is formed by metal plating.

According to a third aspect of the present invention, in the first aspect, the second pattern layer is formed by casting a light or thermosetting resin and then curing the resin by light or heat. In a method for manufacturing a pattern forming die.

According to a fourth aspect of the present invention, in any one of the first to third aspects, a softening point of a resist film obtained after drying the radiation-sensitive negative resist composition is in a range of 30 to 120 ° C. In the method for producing a pattern forming die.

第 A fifth aspect of the present invention is the method for producing a pattern molding die according to any one of the first to fourth aspects, wherein the epoxy resin has a softening point of 30 ° C. or higher.

A sixth aspect of the present invention is the pattern forming mold according to any one of the first to fifth aspects, wherein the radiation-sensitive cationic polymerization initiator is one or more sulfonium salts. Manufacturing method.

A seventh aspect of the present invention, in the first to sixth one embodiment, the at least one anion of the radiation-sensitive cationic polymerization initiator, SbF ₆ ^- pattern forming, which is a It is in the mold manufacturing method.

In an eighth aspect of the present invention, in any one of the first to seventh aspects, at least one kind of anion of the radiation-sensitive cationic polymerization initiator is a borate represented by the following formula (6). A method for manufacturing a pattern forming die, characterized in that:

(Where x _{1 to} x ₄ represent an integer of 0 to 5, and the sum of x ₁ + x ₂ + x ₃ + x ₄ is 1 or more.)

A ninth aspect of the present invention is the method for manufacturing a pattern forming die according to any one of the first to eighth aspects, wherein the active energy ray is an X-ray having a wavelength of 0.1 to 5 nm. .

A tenth aspect of the present invention is the method for producing a pattern forming die according to any one of the first to ninth aspects, wherein the thickness of the resist film is 50 μm or more.

According to the present invention, it is possible to manufacture a pattern forming mold from a high aspect pattern that can be formed easily and with various light sources with high productivity. The pattern forming mold obtained by the production method of the present invention can be used as a "mold" for forming another part having the same pattern as the resist pattern. Further, the pattern forming die itself obtained by the production method of the present invention can be used as a component such as a micromachine or a microchip.

The present invention is formed by using a variety of light sources with high productivity, by selecting an epoxy resin represented by the general formula (1) from a large number of curable resin compositions conventionally existing. Thus, a resist pattern having a high aspect ratio can be obtained, and a pattern forming die can be suitably manufactured using the resist pattern. Such an epoxy resin is disclosed in JP-A-60-166675, and a curable resin composition containing this epoxy resin and a photoinitiator as main components is described in JP-A-61-283614. Although published in the gazette, it was originally developed as a simple UV-curable resin composition, and there is no mention of pattern formation, and of course, a pattern forming mold made of metal or the like as in the present invention. There is no description suggesting a method of manufacturing a metal mold, particularly a method of manufacturing a pattern forming die for forming a thick film pattern such as the LIGA process. It is not easily anticipated that the effect of being able to suitably manufacture a pattern forming mold from a resist pattern having an aspect ratio is exhibited.

The method for producing a pattern-forming mold according to the present invention comprises a method of preparing a radiation-sensitive negative resist composition comprising an epoxy resin represented by the general formula (1), a radiation-sensitive cationic polymerization initiator, and a solvent for dissolving the epoxy resin. A first step of coating a substrate, a second step of drying the substrate coated with the radiation-sensitive negative resist composition to obtain a resist film, and a step of irradiating the obtained resist film with active energy rays. A third step of selectively exposing according to the pattern of the above, a fourth step of improving the contrast by heat-treating the exposed resist film, and a resist in an unexposed area by developing the resist film after the heat treatment. A fifth step of dissolving and removing the material to obtain a pattern layer, and providing another material in at least a concave portion of the pattern layer to form a second pattern layer; Release and a sixth step of the pattern mold with.

The radiation-sensitive negative resist composition applied to the substrate in the first step comprises an epoxy resin represented by the general formula (1), a radiation-sensitive cationic polymerization initiator, and a solvent for dissolving the epoxy resin. Including. When such a radiation-sensitive negative resist is used, coating can be performed by a simple method such as spin coating and a method having high film thickness accuracy and film thickness controllability. The softening point of the resist film obtained after drying the radiation-sensitive negative resist composition is not particularly limited, but is preferably in the range of 30 to 120 ° C, more preferably 35 to 100 ° C, and more preferably 40 to 80 ° C. Use those in the range of ° C. The softening point referred to herein is defined for a resist film obtained after predetermined drying, and the resist film obtained after predetermined drying is obtained by applying a radiation-sensitive negative resist composition to a substrate, drying the resist composition, and drying the resist. Refers to a resist film obtained such that the amount of solvent remaining in the coating film is 10% by weight or less. The resist film obtained after this drying continuously changes from a solid state having a high viscosity to a fluid state having a low viscosity when heated, but the temperature at which a specific viscosity is exhibited during the softening process is increased after drying. The softening point of the obtained resist film, specifically, a measured value obtained by using the method of JIS K 7234.

The softening point of the resist film obtained after drying the radiation-sensitive negative resist composition measured in this way is mainly the type and content of the epoxy resin and the radiation-sensitive cationic polymerization initiator, and furthermore, the solvent remaining during drying and It depends on the type and amount of other additives, and conversely, by changing them, the softening point can be adjusted. The softening point of the resist film obtained after drying so that the amount of the solvent remaining in the resist coating film is 10% by weight or less is preferably in the range of 30 to 120 ° C. It does not specify the dry state when the composition is used. Therefore, even when a composition having a softening point in the above-mentioned range is used, it may be used in the second step, for example, such that the amount of the solvent remaining after the drying step exceeds 10% by weight.

In addition, such a negative resist composition can be used for processing a thick film having a thickness of more than 50 μm. It is necessary to remove the stress caused by the volume reduction accompanying the distillation of water. This is because, in the case of a thick film, the influence of stress becomes particularly remarkable, and problems such as generation of wrinkles, cracks and bubbles in the resist film are likely to occur. As described above, when the negative resist composition having the softening point of the resist film obtained after drying in the above temperature range is used, the stress is relaxed by softening the resist film during the drying step, and the generation of wrinkles and the like of the resist film occurs And tack is not generated at room temperature.

The polyether type epoxy resin represented by the general formula (1) is, for example, a vinyl ether of a polyether compound obtained by reacting an organic compound having active hydrogen with 4-vinylcyclohexene-1-oxide in the presence of a catalyst. The group is obtained by partially or completely epoxidizing a group with an oxidizing agent such as a peracid such as peracetic acid or a hydroperoxide. At this time, a small amount of an acyl group or the like may be introduced. Examples of the organic compound having active hydrogen include alcohols, for example, linear or branched aliphatic alcohols, preferably polyhydric alcohols such as trimethylolpropane, and phenols, carboxylic acids, amines, and thiols. Is mentioned. These organic compounds having active hydrogen preferably have a molecular weight of 10,000 or less. The residue from which the active hydrogen has been removed from the organic compound having active hydrogen is R ^{1 in the} formula (1). In addition, it can be easily obtained from the market, and examples thereof include EHPE-3150 (epoxy equivalent: 170 to 190, softening point: 70 to 90 ° C.) manufactured by Daicel Chemical Industries, Ltd.

The softening point of the epoxy resin represented by the general formula (1) is not particularly limited, but is preferably 30 ° C. or higher, and more preferably 40 ° C., because if it is too low, the resist film after drying tends to be tacky. ~ 140 ° C.

The radiation-sensitive cationic polymerization initiator contained in the radiation-sensitive negative resist composition can be used without particular limitation as long as it can generate an acid by irradiating a known active energy ray, and examples thereof include a sulfonium salt. , Iodonium salts, phosphonium salts or pyridinium salts.

Examples of the sulfonium salt include triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, bis (4- (diphenylsulfonio) -phenyl) sulfide-bis (hexafluorophosphate), and bis (4- (diphenylsulfonate) Nio) -phenyl) sulfide-bis (hexafluoroantimonate), 4-di (p-toluyl) sulfonio-4'-tert-butylphenylcarbonyl-diphenylsulfide hexafluoroantimonate, 7-di (p-toluyl) sulfonio 2-isopropylthioxanthone hexafluorophosphate, 7-di (p-toluyl) sulfonio-2-isopropylthioxanthone hexafluoroantimonate, and the like, and JP-A-7-61964 Publication, Hei 8-165290, JP No. 4231951, and aromatic sulfonium salts described in U.S. Patent No. 4,256,828 and the like.

Examples of the iodonium salt include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, bis (dodecylphenyl) iodonium tetrakis (pentafluorophenyl) borate, JP-A-6-184170, U.S. Pat. No. 4,256,828 and the like. And the like.

Examples of the phosphonium salt include, for example, tetrafluorophosphonium hexafluorophosphate, tetrafluorophosphonium hexafluoroantimonate, and aromatic phosphonium salts described in JP-A-6-157624.

Examples of the pyridinium salt include, for example, pyridinium salts described in Japanese Patent No. 2519480 and Japanese Patent Application Laid-Open No. 5-222112.

The negative resist composition can be used for processing a thick film having a thickness of more than 50 μm. In such a thick film processing, a difference from a known epoxy-containing resist used for forming a thin film is a resist solution. The drying time in the drying step after coating is longer and the developing time in the developing step is longer. Therefore, the negative resist composition requires a high thermal stability and a high contrast between the exposed and unexposed portions in order to form a thick film. Therefore, among the radiation-sensitive cationic polymerization initiators described above, sulfonium When salts are used, the thermal stability of the negative resist composition increases, so that the radiation-sensitive cationic polymerization initiator is preferably one or more sulfonium salts.

Further, it is preferable that at least one kind of anion of the radiation-sensitive cationic polymerization initiator is SbF ₆ ⁻ or a borate represented by the following formula (6), since the contrast of the negative resist composition is increased. More preferred examples of the borates include tetrakis (pentafluorophenyl) borate.

(Where x _{1 to} x ₄ represent an integer of 0 to 5, and the sum of x ₁ + x ₂ + x ₃ + x ₄ is 1 or more.)

Sulfonium salts and iodonium salts are also readily available on the market. Examples of radiation-sensitive cationic polymerization initiators that can be easily obtained from the market include UVI-6990 and UVI-6974 manufactured by Union Carbide, and Adeka Optomer SP-170 and Adeka manufactured by Asahi Denka Kogyo KK. Examples include sulfonium salts such as Optomer SP-172 and iodonium salts such as PI 2074 manufactured by Rhodia.

添加 The amount of the radiation-sensitive cationic polymerization initiator to be added is not particularly limited, but is preferably 0.1 to 15 parts by weight, more preferably 1 to 12 parts by weight, based on 100 parts by weight of the epoxy resin.

The solvent for dissolving the epoxy resin contained in the radiation-sensitive negative resist composition is not particularly limited as long as it is a solvent for dissolving the epoxy resin.For example, propylene glycol monomethyl ether acetate, propylene such as propylene glycol monoethyl ether acetate, etc. Glycol monoalkyl ether acetates, alkyl lactates such as methyl lactate and ethyl lactate, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and the like Ethylene glycol monoalkyl ethers, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether Ethylene glycol monoalkyl ether acetates such as acetate, 2-heptanone, γ-butyrolactone, methyl methoxypropionate, alkyl alkoxypropionates such as ethyl ethoxypropionate, alkyl pyruvate such as methyl pyruvate and ethyl pyruvate , Methyl ethyl ketone, ketones such as cyclopentanone and cyclohexanone, N-methylpyrrolidone, N, N-dimethylacetamide, dimethyl sulfoxide, propylene carbonate, diacetone alcohol and the like. These solvents can be used alone or as a mixture. Among the above solvents, γ-butyrolactone is particularly preferred.

The radiation-sensitive negative resist composition containing each of the above components preferably contains 10 to 90% by weight, more preferably 40 to 85% by weight, of a solid content as a solid content in a solvent in which the epoxy resin is dissolved. And more preferably 60 to 80% by weight. If the solid content is too low, it is difficult to apply a sufficient film thickness, and if the solid content is too high, the viscosity becomes high and the application becomes difficult.

In addition, various additives such as a surfactant, an acid diffusion inhibitor, a pigment, a dye, a sensitizer, and a plasticizer can be added to the radiation-sensitive negative resist composition as needed.

The support substrate on which the negative resist composition is applied and the surface thereof are not particularly limited. Examples of the substrate include silicon, glass, metal, ceramic, and organic polymers. These substrates may be subjected to a pretreatment of the substrate for the purpose of improving the adhesiveness and the like. For example, an improvement in the adhesiveness can be expected by performing a silane treatment. Further, when obtaining a metal pattern forming die, the plating step can be easily performed if the surface of the base material is made conductive.

The step of applying the radiation-sensitive negative-type resist composition to the substrate is not particularly limited, and an application method such as screen printing, curtain coating, blade coating, spin coating, spray coating, dip coating, or slit coating can be applied. .

(4) The substrate coated with the radiation-sensitive negative resist composition in the first step is dried in the second step to obtain a resist film. The drying step is not particularly limited, but it is preferable to perform the drying step at a temperature and for a time at which the solvent contained in the negative resist composition volatilizes and a tack-free resist film can be formed. Further, it is preferable that the temperature and the time are such that the epoxy resin, the radiation-sensitive cationic polymerization initiator, and other additives added as required do not cause a thermal reaction to cause a problem in pattern formation. Therefore, the drying conditions are preferably, for example, 40 to 120 ° C. and 5 minutes to 24 hours. The thickness of the resist film is not particularly limited. For example, a thick film having a thickness of 50 μm or more can be processed with high accuracy in the subsequent steps, but is preferably 50 μm to 2 mm.

(4) The resist film obtained in the second step is selectively exposed to a desired pattern by an active energy ray in a third step. The active energy ray used for exposure is not particularly limited. Examples of the active energy ray include an ultraviolet ray, an excimer laser, an electron beam, and an X-ray, and it is particularly preferable to use an X-ray having a wavelength of 0.1 to 5 nm because the pattern accuracy is improved. In the manufacturing method of the present invention, since the radiation-sensitive negative resist composition as described above is used, for example, even if the resist film is formed to a thickness of 50 μm or more, the exposure time in this exposure step is short, and the active energy Lines can be selected according to a desired pattern accuracy. For example, highly versatile ultraviolet rays (light source: high-pressure mercury lamp, etc.) can be used, so that the productivity is excellent.

{Circle around (4)} The contrast of the resist film exposed in the third step is improved by heat in the fourth step. If this step is omitted, the reaction of the epoxy resin is not sufficient, and an accurate pattern cannot be obtained. In the fourth step, it is necessary to perform the heat treatment at a temperature and for a time within a range in which the unexposed portion of the resist does not cause a thermal reaction to become insoluble in the developing solution. The preferred temperature is 70 to 110 ° C, more preferably 80 to 100 ° C, and the preferred time is 5 minutes to 10 hours. If the temperature is lower than the above range or the time is too short, the contrast becomes insufficient, and if the temperature is too high or the time is too long, unexposed portions become insoluble in a developing solution.

(4) The resist film that has been heat-treated in the fourth step is developed in the fifth step to dissolve and remove the resist material in the unexposed area to obtain a pattern layer. In the present invention, since the resist film is thick and has high strength and excellent resolution, a pattern layer having a high aspect pattern can be formed. For example, a pattern having an aspect ratio of 10 or more can be used. it can.

The developer is not particularly limited as long as it is a solvent that dissolves and removes the negative resist in the unexposed portions, but propylene glycol monomethyl ether acetate, propylene glycol monoalkyl ether acetates such as propylene glycol monoethyl ether acetate, methyl lactate, Lactic acid alkyl esters such as ethyl lactate, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, ethylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and ethylene glycol monomethyl Ethylene glycol monoalkyl ethers such as ether acetate and ethylene glycol monoethyl ether acetate Acetates, 2-heptanone, γ-butyrolactone, alkyl alkoxypropionates such as methyl methoxypropionate, ethyl ethoxypropionate, alkyl pyruvates such as methyl pyruvate, ethyl pyruvate, methyl ethyl ketone, cyclopentanone, cyclohexanone And the like, N-methylpyrrolidone, N, N-dimethylacetamide, dimethylsulfoxide, propylene carbonate, diacetone alcohol, and γ-butyrolactone, propylene glycol monomethyl ether acetate and the like are particularly preferable.

The method of development may be any of a spray method, a paddle method, an immersion method and the like, but an immersion method is preferable because pattern destruction such as pattern peeling is small. Further, ultrasonic waves or the like can be irradiated as needed.

In the fifth step, a rinsing step is preferably performed as necessary after the development, but the rinsing step, the rinsing liquid and the rinsing method are not particularly limited, and the rinsing step can be performed by a known liquid and method.

(4) After the development or rinsing step, the resist pattern can be stabilized by heating the resist pattern under known conditions.

A second pattern layer is formed by providing another material in at least the concave portion of the pattern layer obtained in the fifth step, and separating the second pattern layer into a pattern forming mold by a sixth step. Obtain a pattern mold. That is, as shown in FIGS. 1 and 2, for example, the second pattern is formed of another material at least in the concave portions of the pattern layer 2 (FIGS. 1A and 2A) formed on the substrate 1. By providing the layer 3, a composite structure of the pattern layer 2 and the second pattern layer 3 can be obtained (FIGS. 1 (b) and 2 (b)). Note that the second pattern layer 3 may be provided only in the concave portion of the pattern layer 2 or may be provided on the entire surface so as to cover the pattern layer 2. When the second pattern layer 3 is separated from the composite structure of the pattern layer 2 and the second pattern layer 3, a pattern forming mold 4 to which the resist pattern of the pattern layer 2 has been transferred is obtained (FIG. 1C). 2 (c)). The pattern forming mold 4 can be used as a "mold" for molding other parts, but can also be used as a part as it is.

As described above, in the present invention, since a resist pattern layer having a high aspect pattern can be formed, a pattern mold for transferring the high aspect pattern can be manufactured. For example, the aspect ratio is 10 or more. It can also be.

材料 The material for forming the second pattern layer 3 is not particularly limited, but when the material is metal, for example, if it is provided by a plating process, a metal pattern forming die can be obtained.

The method of the plating step is not particularly limited, but an electrolytic plating method is preferable. As a method of performing metal plating such as copper, nickel, silver, gold, solder, copper / nickel multilayer, or a composite system thereof, a conventionally known method can be used. For example, “Surface treatment technology overview” ( Technical Data Center Co., Ltd., the first edition of 1987/12/21, p. 281 to 422.

工程 The step of separating the second pattern layer 3 provided by the plating step from the composite structure of the pattern layer 2 and the second pattern layer 3 is not particularly limited, but a known wet method or dry method can be used. For example, in the wet method, a method such as immersion in a chemical such as an organic solvent such as N-methylpyrrolidone or an organic alkali solution such as ethanolamine is used. In the dry method, a dry etching method such as reactive ion etching or an ashing treatment is used. Can be

The material for forming the second pattern layer 3 may be a resin. In this case, for example, the second pattern layer 3 is provided by casting of a light or thermosetting resin, and the resin is cured by light or heat. Then, a pattern mold for resin can be obtained.

The step of separating the second pattern layer 3 made of a light or thermosetting resin from the composite structure of the pattern layer 2 and the second pattern layer 3 is not particularly limited, but may be, for example, physically peeled off. If the second pattern layer 3 has sufficient resistance to the above-mentioned wet method or dry method, these methods can also be used. The light or thermosetting resin is not particularly limited. For example, when light or thermosetting PDMS (polydimethylsiloxane) is used, the pattern can be transferred by being easily cured by light or heat, and from the resist pattern. This is particularly preferable because it can be easily physically peeled off at the time of separation.

As described above, according to the present invention, a resist composition can be applied by a simple method such as spin coating and a high film thickness accuracy and high film thickness controllability, and a desired pattern accuracy and a wide selection range of an exposure light source are large. A pattern forming mold made of metal, resin, and the like can be manufactured from a resist pattern having a short exposure time, high productivity, and a high aspect pattern and a high aspect ratio.

本 The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

{1. Preparation of radiation-sensitive negative resist composition for pattern formation

(Examples 1 to 4)
The resist materials were mixed in the proportions shown in Table 1 to form a uniform composition using a three-roll mill to prepare a radiation-sensitive negative resist composition for pattern formation. The structural formulas and trade names of the epoxy resin and the cationic polymerization initiator are shown in [Formula 8] and [Formula 9] below.

Resin-1: EHPE-3150 (trade name: Daicel Chemical Industries epoxy resin)
Resin-2: EPON SU-8 (trade name: Epoxy resin manufactured by Shell Chemical)

PI-1: UVI-6974 (trade name: Union Carbide, cationic initiator, active ingredient 50 wt%, a mixture containing the above compound as a main component)
PI-2: UVI-6990 (trade name: Union Carbide cationic initiator, active ingredient 50 wt%, a mixture containing the above compound as a main component)
PI-3: SarCat CD-1012 (trade name: Sartomer Cation Initiator)
PI-4: mixture containing the above compounds as main components

(Comparative Example 1)
In the same manner as in Examples 1 to 4, a radiation-sensitive negative resist composition for pattern formation having the composition shown in Table 1 was prepared.

{2. Patterning evaluation

(1) Preparation of resist film (Examples 1a to 4a)
After applying the radiation-sensitive negative resist composition for pattern formation of Examples 1 to 4 on a silicon substrate having been subjected to copper surface treatment by a sputtering method using a spin coater, the composition is dried on a hot plate at 90 ° C. for 30 minutes. A resist film having a thickness of 100 μm was obtained.

(Comparative Example 1a)
Using the radiation-sensitive negative resist composition for pattern formation of Comparative Example 1 in place of the radiation-sensitive negative resist composition for pattern formation of Examples 1-4, a 100 μm resist was prepared in the same manner as in Examples 1a-4a. A membrane was obtained.

(Comparative Example 2a)
PMMA syrup (PMM (polymethyl methacrylate) manufactured by Rohm, MMA (methyl methacrylate) solution of a thermal polymerization initiator and a crosslinking agent) was cast on a silicon substrate. At that time, the slide glass was used as a gap, pressed with a glass plate, and polymerized and cured at 110 ° C. for 1 hour. Thereafter, cooling was performed at a rate of 15 ° C./hour to obtain a 100 μm-thick PMMA resist film.

(Test Example 1)
In order to evaluate the uniformity (coatability) of the resist films obtained in Examples 1a to 4a and Comparative Examples 1a and 2a, film thicknesses at three arbitrary points on the substrate were measured. The applicability was evaluated as “差” when the difference between the maximum value and the minimum value of the measured value was less than 5 μm, “○” when it was 5 to 10 μm, and “×” when it exceeded 10 μm. Table 2 shows the results.

(2) Formation of resist pattern (Examples 1b to 4b)
When a high-pressure mercury lamp is used as the light source and when a KrF excimer laser is used, a quartz UV mask is used as a mask, and when X-rays (wavelength: 0.2 to 1 nm) using synchrotron light are used, the diamond membrane is used. The resist film of each of Examples 1a to 4a was irradiated with an X-ray mask having a gold absorber pattern formed thereon, and then heat-treated on a hot plate at 90 ° C. for 10 minutes, and then propylene glycol monomethyl ether acetate was added. And developed for 30 minutes to obtain a resist pattern. The exposure amounts are shown in Table 2.

(Comparative Example 1b)
A resist pattern was obtained in the same manner as in Examples 1b to 4b, except that the resist film of Comparative Example 1a was used instead of the resist films of Examples 1a to 4a.

(Comparative Example 2b)
After irradiating the PMMA resist film of Comparative Example 2a using a mask in the same manner as in Examples 1b to 4b, the PMMA resist film was immersed in a mixture of ethanol, oxazine, aminoethanol, and water for 12 hours in the state of being subjected to ultrasonic wave to perform development. Thus, a resist pattern was obtained.

(Test Example 2)
The resist patterns obtained in Examples 1b to 4b and Comparative Examples 1b and 2b were observed with an optical microscope. When there was no meandering of the pattern due to swelling, “◎” was observed. The sensitivity was evaluated as “O” when no pattern was observed and “X” when the pattern was meandering.

In addition, when the resist pattern resolves a pattern having a mask line width of 10 μm (aspect ratio 10), the symbol “、” indicates that the pattern has a mask line width of 20 μm (aspect ratio 5). The resolution was evaluated as “x” when not performed. Table 2 shows the results.

Examples 1a and 4a had good coatability, and Examples 1b and 4b showed good results under all X-ray exposure conditions using a high-pressure mercury lamp, a KrF excimer laser, and synchrotron light.

Example 2a had good coating properties, and Example 2b showed generally good results although curing sensitivity was slightly inferior to Example 1b.

Example 3a had good coatability, and Example 3b showed a generally good result although the developing speed of the unexposed portion was slow and some adverse effects were observed on the pattern property and the like.

Comparative Example 1a had good coatability, and Comparative Example 1b showed good results by exposure to X-rays using a high-pressure mercury lamp and synchrotron light, but failed to form a pattern when exposed to KrF excimer laser.

In Comparative Example 2a, a resist film having a uniform film thickness could not be obtained, and in Comparative Example 2b, the pattern could not be formed unless the exposure conditions were increased to 10,000 J / cm ² with synchrotron light to a practically difficult exposure amount. confirmed.

{3. Measurement of softening point and appearance test of resist film obtained after drying

(Test Example 3)
For the resist film of Example 1a, measurement was performed according to the method of JIS K 7234 and the state of the film was visually observed. As a result, the softening point was 60 ° C., and the resulting resist film was free from tack and wrinkles.

4. Forming a metal pattern mold

(Example 1c)
The substrate on which the resist pattern of Example 1b was formed was immersed in microfabric Au100 (trade name: plating solution made by Tanaka Kikinzoku), and a current of 1 to 10 A / 100 cm ² was applied at room temperature to apply an Au plating layer (second pattern layer). ) Was formed. This is immersed in an aqueous solution adjusted to a concentration of 250 g / L of chromium (VI) oxide and 15 mL / L of sulfuric acid, separated from the substrate by etching copper on the substrate, and then N-methylpyrrolidone at 120 ° C. The resist pattern was removed by immersion in the solution for 2 hours to obtain a metal (Au) pattern forming mold.

(Comparative Example 2c)
Example 1c was performed in the same manner as in Example 1c except that the substrate on which the resist pattern of Comparative Example 2b was formed was used instead of Example 1b.

(Test Example 4)
The metal pattern forming dies obtained in Example 1c and Comparative Example 2c were observed with a microscope, and the reverse pattern shape in which plating was performed uniformly and the resist pattern before the plating process was transferred was accurately detected. The case where it was formed was evaluated as “○”, and the case where plating was not performed uniformly and / or where a reverse pattern shape to which the resist pattern was transferred was not obtained was evaluated as “×”. Table 3 shows the results.

5. Forming a resin pattern mold

(Example 1d)
Unpolymerized PDMS (Dow Corning, Sylgard 184) mixed at a ratio of main agent: polymerizing agent = 10: 1 was poured onto the substrate on which the resist pattern of Example 1b was formed, and was heated and polymerized at 100 ° C. for 2 hours. The substrate was cooled to room temperature, and the cured PDMS was physically peeled off from the substrate to obtain a resin (PDMS) pattern mold.

(Comparative Example 2d)
Example 1d was repeated except that the substrate on which the resist pattern of Comparative Example 2b was formed was used instead of Example 1b.

(Test Example 5)
The resin pattern molds obtained in Example 1d and Comparative Example 2d were observed with a microscope, and the PDMS pattern was free from any damage to the resist pattern, and the reverse pattern shape on which the resist pattern was transferred was accurately detected. The case where it was formed was evaluated as “○”, the case where there was a breakage, and / or the case where there was a portion where the reverse pattern shape to which the resist pattern was transferred was not obtained was evaluated as “×”. Table 3 shows the results.

As shown in Table 3, in Examples 1c and 1d, a metal pattern molding die and a resin pattern molding die were successfully formed. In addition, since a favorable resist pattern was obtained also in the other Examples, it is possible to form a good metal pattern molding die and a resin pattern molding die similarly to Examples 1c and 1d. Guessed. On the other hand, in Comparative Examples 2c and 2d, most of the resist patterns could not be formed as described above, so that a metal pattern molding die or a resin pattern molding die could not be provided. Even if the synchrotron light formed was increased to a practically difficult exposure amount of 10,000 J / cm ² , the mechanical strength of the resist pattern was insufficient, so that a resin pattern mold could be satisfactorily provided. Did not.

It is a figure showing the manufacturing method of the pattern forming die concerning one embodiment of the present invention. It is a figure showing the manufacturing method of other pattern fabrication dies concerning one embodiment of the present invention.

Explanation of reference numerals

Reference Signs List 1 substrate 2 pattern layer 3 second pattern layer 4 pattern forming die

Claims (10)

A first step of applying a radiation-sensitive negative resist composition containing an epoxy resin represented by the general formula (1), a radiation-sensitive cationic polymerization initiator, and a solvent for dissolving the epoxy resin to a substrate, A second step of drying the substrate coated with the radiation-sensitive negative type resist composition to obtain a resist film, and a third step of selectively exposing the obtained resist film to a desired pattern with active energy rays. A fourth step of improving the contrast by heat-treating the exposed resist film, and a fifth step of developing the resist film after the heat treatment to dissolve and remove the resist material in the unexposed area to obtain a pattern layer. And a sixth step of forming a second pattern layer by providing another material in at least a concave portion of the pattern layer, and separating the second pattern layer into a pattern forming die. Method of manufacturing a patterned mold, characterized in that it comprises a.

(Wherein, R ¹ is k organic compound residues having active hydrogen (k is an integer of 1 to 100), n ₁ , n ₂ ... _Nk are 0 or an integer of 1 to 100. , The sum of which is 1 to 100, and A is the same or different, and is an oxycyclohexane skeleton represented by the following formula (2).)

(In the formula, X represents any of the following formulas (3) to (5), but includes at least two formulas (3) in one molecule.)

(In the formula, R ² is a hydrogen atom, an alkyl group, or an acyl group.) 2. The method according to claim 1, wherein the second pattern layer is formed by metal plating. 2. The method according to claim 1, wherein the second pattern layer is formed by casting a light or thermosetting resin and then curing the resin with light or heat. The method according to any one of claims 1 to 3, wherein the softening point of the resist film obtained after drying the radiation-sensitive negative resist composition is in the range of 30 to 120C. 5. The method according to claim 1, wherein the epoxy resin has a softening point of 30 [deg.] C. or more. The method according to any one of claims 1 to 5, wherein the radiation-sensitive cationic polymerization initiator is one or more sulfonium salts. In any one of claims 1 to 6, at least one anion of the radiation-sensitive cationic polymerization initiator, SbF ₆ ^- method of manufacturing a patterned mold, which is a. The pattern forming mold according to any one of claims 1 to 7, wherein at least one kind of anion of the radiation-sensitive cationic polymerization initiator is a borate represented by the following formula (6). Production method.

(Where x _{1 to} x ₄ represent an integer of 0 to 5, and the sum of x ₁ + x ₂ + x ₃ + x ₄ is 1 or more.) The method according to any one of claims 1 to 8, wherein the active energy ray is an X-ray having a wavelength of 0.1 to 5 nm. 10. The method according to claim 1, wherein the resist film has a thickness of 50 [mu] m or more.

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