JP2007133108A - Photosensitive solder resist composition and film, and permanent pattern and method of forming same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive solder resist composition having high sensitivity and small surface tackiness in a blue-violet laser exposure system, excellent in strippability, adhesion to a substrate and storage stability, and providing a cured film having excellent insulation, heat resistance, chemical resistances and surface hardness after development and also provide a photosensitive solder resist film obtained by using the composition, a high-definition permanent pattern, and a method of efficiently forming the pattern. <P>SOLUTION: The photosensitive solder resist composition contains an alkali-soluble photocrosslinkable resin, a polymerizable compound, a photopolymerization initiator, a heat crosslinking agent, a heat curing accelerator and a colorant, wherein the photosensitive solder resist composition contains a (meth)acrylamide copolymer having an acid number of 90-200 mgKOH/g and a mass average molecular weight of 30.000-80,000 (other than a (meth)acrylamide copolymer having a self-condensing group as a substituent) in an amount of 10-50 mass% based on the amount of the alkali-soluble photocrosslinkable resin. The photosensitive film obtained by using the composition, the permanent pattern and the method for forming the pattern are also provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a photosensitive solder resist composition capable of adjusting the surface tackiness of the photosensitive solder resist layer when used as a photosensitive solder resist layer of a photosensitive solder resist film, and a photosensitive solder using the same. -Related solder resist film and high-definition permanent patterns (protective film, interlayer insulation film, solder resist, etc.), especially used for wiring boards and electronic component modules, and heat history and temperature cycle test (TCT) during mounting The present invention relates to a permanent pattern excellent in heat fatigue resistance against insulation, excellent in insulation, heat resistance, storage stability, chemical resistance, surface hardness, and the like, and an efficient formation method thereof.

  In the field of printed wiring boards, components such as semiconductors, capacitors and resistors are soldered onto the printed wiring board. In this case, for example, in a soldering process such as IR reflow, in order to prevent the solder from adhering to an unnecessary part of soldering, a permanent pattern corresponding to the unnecessary part of soldering is used as a protective film and an insulating film. The method of forming is adopted. A solder resist is preferably used as the permanent pattern of the protective film.

  Conventionally, as the solder resist, a thermosetting material is often used, and a method of printing by a screen printing method is generally used. However, in recent years, with the increase in the wiring density of printed wiring boards, the screen printing method is limited in terms of resolution, and the composition for photo solder resist that forms an image by the photolithography method is actively used. It has become to. Among them, an alkali development type photo solder resist composition that can be developed with a weak alkaline solution such as a sodium carbonate solution has become the mainstream in terms of working environment and global environment conservation.

The alkali development type liquid solder resist composition basically comprises an alkali-soluble photocrosslinkable resin, a polymerizable compound, a photopolymerization initiator, and a thermal crosslinker, and further contains an inorganic filler. And other components appropriately selected from colorants and thermosetting accelerators as necessary.
As a step of forming a permanent pattern on a printed wiring board using the development type solder resist composition, first, the solder resist composition is applied on a circuit board, preliminarily dried, and then a photomask film. To be exposed to light, to cure the solder resist composition of the light-irradiated portion, then to remove unnecessary uncured portions by development, and then to heat completely or completely expose to ultraviolet rays to completely cross-link, There is a step of forming a pattern. However, in the solder resist composition after the preliminary drying, unreacted resin (oligomer) and monomer exist, and therefore the surface of the solder resist composition has tackiness (adhesiveness), thereby creating a photomask film. There are problems that the solder resist composition adheres and the photomask film cannot be reused, and that the resist adheres to the photomask film, resulting in uneven film thickness and exposure defects.

Therefore, in recent years, it is desired to make a solder resist composition a dry film.
The photosensitive solder resist life film for forming a permanent pattern basically has a photosensitive solder resist layer having a thickness of 5 to 80 μm formed from a photosensitive solder resist composition on a flexible transparent support. In addition, it is sandwiched with a peelable protective film. In the method of forming a permanent pattern using this dry film, the handling of liquid and the poor work efficiency seen when using a liquid solder resist composition are remarkably improved, and there is no problem of contamination of the mask film. .

However, when a general liquid resist composition is formed into a dry film, there are many problems.
When high sensitivity and good substrate followability are required, the problem is the peelability of the support and the protective film. In general, a dry film has a photosensitive solder resist layer on a support as described above, and a protective film is attached to the opposite side of the support to protect the photosensitive solder resist layer. First, the protective film is peeled off, the photosensitive solder resist layer is brought into contact with the substrate and deaerated in a vacuum chamber of a vacuum laminator, and then sufficient adhesion between the support and the photosensitive solder resist layer is realized by heating and pressing. .
In this process, it is important to adjust the tackiness of the surface of the photosensitive solder resist layer. That is, if the tackiness is too high, sufficient deaeration cannot be performed between the substrate and the photosensitive solder resist layer, leaving bubbles, and a pinhole is opened after development, so that a sufficient protective function cannot be expected.

On the other hand, as the exposure to the photosensitive solder resist layer, conventionally, exposure using a photomask has been generally performed. However, in recent years, high productivity of printed circuit boards and reduction of defective rate are pursued. Therefore, a maskless laser exposure system has attracted attention.
In the recent trend of these resist materials and systems, development of a dry film having high sensitivity and high sensitivity to a blue-violet laser with excellent film thickness uniformity has been actively conducted. However, no dry film that satisfies the target performance for high sensitivity and sufficient adhesion to the substrate has yet appeared on the market.

In order to solve such problems, it is known to add an acrylamide copolymer to the solder resist composition for the purpose of improving tackiness. Examples of such additives include alkoxymethylated acrylamide. Copolymers (see Patent Documents 1 and 2) have been proposed. However, since these copolymers have a low glass transition temperature (Tg), the thermal stability is inferior, and the tack improving effect is not sufficient.
As an acrylamide copolymer, an acrylamide copolymer containing an amino group (see Patent Document 3) has been proposed. However, since these copolymers have amino groups, when they are added, they form a salt with an alkali-soluble photocrosslinkable resin and become hydrophilic, so that the water resistance of the cured film is insufficient. there were.

  Therefore, when used as a photosensitive solder resist layer of a photosensitive solder resist film, a photosensitive solder resist composition capable of adjusting the surface tackiness of the photosensitive solder resist layer, and the photosensitive solder resist layer The photosensitive solder resist composition which can improve the peelability of the support and the protective film of the photosensitive solder resist film by reducing the surface tackiness of the photosensitive solder resist film, and the permanent As for the pattern and its efficient formation method, there is not yet a satisfactory one yet.

JP-A-6-230571 JP 7-281437 A JP-A-57-20732

An object of the present invention is to solve the conventional problems and achieve the following objects. That is, the present invention is a photosensitive solder resist layer having a small surface tackiness and excellent peelability of the support and protective film when used as the photosensitive solder resist layer of the photosensitive solder resist film. It aims at providing a soldering resist composition.
Furthermore, the present invention has high sensitivity, excellent adhesion to a substrate and storage stability in a blue-violet laser exposure system, and has excellent insulation, heat resistance, chemical resistance, surface hardness, etc. after development. Photosensitive solder resist composition suitable as photosensitive solder resist layer of photosensitive solder resist film from which cured film is obtained, photosensitive solder resist film using the same, and high-definition permanent pattern (protective film, interlayer insulating film) An object of the present invention is to provide a solder resist pattern and the like and an efficient formation method thereof.

Means for solving the problems are as follows. That is,
<1> A photosensitive solder resist composition comprising an alkali-soluble photocrosslinkable resin, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, a thermosetting accelerator, and a colorant,
Further, a (meth) acrylamide copolymer having an acid value of 90 to 200 mg KOH / g and a weight average molecular weight of 30,000 to 80,000 (excluding those having a self-condensable group as a substituent) is described above. A photosensitive solder resist composition comprising 15 to 50% by mass of an alkali-soluble photocrosslinkable resin.
In the photosensitive solder resist composition according to <1>, since the (meth) acrylamide copolymer is contained in an amount of 15 to 50% by mass of the alkali-soluble photocrosslinkable resin, the photosensitive solder resist film When used as a photosensitive solder resist layer, the surface tackiness of the photosensitive solder resist layer is small. Therefore, the photosensitive solder resist film formed by such a photosensitive solder resist composition is excellent in the peelability of the support and protective film on the photosensitive solder resist layer, and as a result, the photosensitive solder resist layer. Is exposed to high-definition, and then the photosensitive solder resist layer is developed, a high-definition pattern can be obtained.
<2> The photosensitive solder resist composition according to <1>, wherein the (meth) acrylamide copolymer has a glass transition temperature (Tg) of 420 K or more.
<3> The photosensitive solder resist composition according to any one of <1> to <2>, wherein the (meth) acrylamide copolymer is a copolymer represented by the following general formula (I).
In the general formula (I), R ¹ represents hydrogen or a methyl group, R ² represents an alkoxycarbonyl, an optionally substituted aryl group (provided that the substituent is not included in the self-condensing group) of at least R ³ represents an alkyl group, an alkyl group that may be substituted (provided that the substituent does not include a self-condensable group), an aryl group, or an aryl group that may be substituted (provided that the substituent The substituent does not include a self-condensable group.
Moreover, x, y, and z represent the mass composition ratio of a repeating unit, and are x: y: z = 15-30: 20-60: 25-50, and x + y + z = 100.
<4> The photosensitive solder resist composition according to <3>, wherein the (meth) acrylamide copolymer is a copolymer represented by the following general formula (II).
In the general formula (II), R ¹ represents hydrogen or a methyl group, R ² represents an alkoxycarbonyl, an optionally substituted aryl group (provided that the substituent is not included in the self-condensing group) of at least R ³ represents an alkyl group, an optionally substituted alkyl group (however, the substituent does not include a self-condensable group), an aryl group, or an optionally substituted aryl group (provided that the substituted R ⁴ represents an alkyl group, an optionally substituted alkyl group (however, the substituent does not include a self-condensable group), an aryl group, or a substituted group. Represents an aryl group (wherein the substituent does not include a self-condensable group), and R ⁵ represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group.
^{Also, x, y} 1, y ² and z represent weight compositional ratio of the repeating ^{units, x: y 1: y 2} : z = 15~30: 0~60: 0~60: a 25 to 50, y ¹ + ^y 2 = ^20~60, an ^{x + y 1 + y 2 +} z = 100.
<5> The photosensitive solder resist composition according to any one of <1> to <4>, wherein the thermal crosslinking agent is any one of an epoxy resin and a polyfunctional oxetane compound.
<6> The photosensitive solder resist composition according to any one of <1> to <5>, including an inorganic filler.
<7> The photosensitive solder resist composition according to any one of <1> to <6>, wherein the polymerizable compound includes at least one selected from monomers having a (meth) acryl group.
<8> At least the photopolymerization initiator is selected from halogenated hydrocarbon derivatives, phosphine oxides, hexaarylbiimidazoles, oxime derivatives, organic peroxides, thio compounds, ketone compounds, aromatic onium salts, and ketoxime ethers. It is the photosensitive soldering resist composition in any one of said <1> to <7> containing 1 type.

<9> A support, and a photosensitive solder resist layer in which the photosensitive solder resist composition according to any one of <1> to <8> is laminated on the support. And a photosensitive solder resist film.
<10> The photosensitive solder resist film according to <9>, wherein the protective solder resist layer is provided on the photosensitive solder resist layer.
<11> The photosensitive solder resist film according to any one of <9> to <10>, wherein the photosensitive solder resist layer has a thickness of 3 to 100 μm.
<12> The photosensitive solder resist film according to any one of <9> to <11>, wherein the support contains a synthetic resin and is transparent.
<13> The photosensitive solder resist film according to any one of <9> to <12>, wherein the support has a long shape.

<14> The photosensitive solder resist composition according to any one of <1> to <8> is applied to the surface of a substrate, dried to form a photosensitive solder resist layer laminate, and then exposed. , Developing a permanent pattern.
In the method for forming a permanent pattern according to <14>, the photosensitive solder resist composition according to any one of <1> to <8> is applied to a surface of a substrate and dried. Layers are stacked. Thereafter, the photosensitive solder resist layer is exposed, and the exposed photosensitive solder resist layer is developed. As a result, the surface hardness is high, and a permanent pattern optimum for the protective film or insulating film is formed.
<15> The photosensitive solder resist film according to any one of <9> to <13>, wherein the photosensitive solder resist layer is transferred to a surface of a substrate, and then exposed and developed. This is a permanent pattern forming method.
In the method for forming a permanent pattern according to <15>, the photosensitive solder resist film according to any one of <9> to <13> is a surface of a substrate under at least one of heating and pressurization. Then, the photosensitive solder resist layer is laminated, and then the photosensitive solder resist layer is exposed, and the exposed photosensitive solder resist layer is developed. As a result, the surface hardness is high, and a permanent pattern optimum for the protective film or insulating film is formed.
<16> The method for forming a permanent pattern according to any one of <14> to <15>, wherein the base material is a printed wiring board on which wiring is formed.
In the permanent pattern forming method according to <16>, since the base material is a printed wiring board on which wiring has been formed, by using the permanent pattern forming method, a multilayer wiring board or build-up of a semiconductor or a component can be performed. High-density mounting on a wiring board or the like is possible.
<17> The permanent pattern forming method according to any one of <14> to <16>, wherein the exposure is performed imagewise based on pattern information to be formed.
<18> The permanent pattern according to any one of <14> to <17>, wherein the exposure is performed using light that generates a control signal based on pattern information to be formed and is modulated according to the control signal. It is a forming method.
<19> The above <14> to <18, wherein the exposure is performed using a light irradiation unit that irradiates light and a light modulation unit that modulates light emitted from the light irradiation unit based on pattern information to be formed. The permanent pattern forming method according to any one of the above.
<20> The control in which the light modulation unit further includes a pattern signal generation unit that generates a control signal based on pattern information to be formed, and the pattern signal generation unit generates light emitted from the light irradiation unit. The method for forming a permanent pattern according to <19>, wherein modulation is performed according to a signal.
<21> The light modulation means has n pixel parts, and forms any less than n pixel elements continuously arranged from the n pixel parts. The permanent pattern forming method according to any one of <19> to <20>, which is controllable according to pattern information.
In the method for forming a permanent pattern according to <21>, any less than n pixel portions arranged continuously from n pixel portions in the light modulation unit are controlled according to pattern information. By doing so, the light from the light irradiation means is modulated at high speed.
<22> The method for forming a permanent pattern according to any one of <19> to <21>, wherein the light modulator is a spatial light modulator.
<23> The method for forming a permanent pattern according to <22>, wherein the spatial light modulation element is a digital micromirror device (DMD).
<24> The permanent pattern forming method according to any one of <21> to <23>, wherein the picture element portion is a micromirror.
<25> Exposure is performed through a microlens array in which microlenses having aspherical surfaces capable of correcting aberrations due to distortion of the exit surface of the picture element portion in the light modulator after the light is modulated by the light modulator. The method for forming a permanent pattern according to any one of <21> to <24>.
<26> The method for forming a permanent pattern according to <25>, wherein the aspherical surface is a toric surface.
In the permanent pattern forming method according to <26>, since the aspherical surface is a toric surface, the aberration due to the distortion of the radiation surface in the picture element portion is efficiently corrected, and on the photosensitive solder resist layer. The distortion of the image to be formed is efficiently suppressed. As a result, the photosensitive solder resist layer is exposed with high definition. Thereafter, the photosensitive solder resist layer is developed to form a high-definition permanent pattern.
<27> The permanent pattern forming method according to any one of <14> to <26>, wherein the exposure is performed through an aperture array.
In the method for forming a permanent pattern described in <27>, the extinction ratio is improved by performing exposure through the aperture array. As a result, the exposure is performed with extremely high definition. Thereafter, the photosensitive solder resist layer is developed to form a very fine permanent pattern.
<28> The method for forming a permanent pattern according to any one of <14> to <27>, wherein the exposure is performed while relatively moving the exposure light and the photosensitive solder resist layer.
In the method for forming a permanent pattern according to <28>, the exposure is performed at a high speed by performing exposure while relatively moving the modulated light and the photosensitive solder resist layer.
<29> The method for forming a permanent pattern according to any one of <14> to <28>, wherein the exposure is performed on a partial region of the photosensitive solder resist layer.
<30> The method for forming a permanent pattern according to any one of <19> to <29>, wherein the light irradiation unit can synthesize and irradiate two or more lights.
In the method for forming a permanent pattern according to <30>, the light irradiation means can synthesize and irradiate two or more lights, so that exposure is performed with exposure light having a deep focal depth. As a result, the exposure to the photosensitive solder resist layer is performed with extremely high definition. Thereafter, the photosensitive solder resist layer is developed to form a very fine permanent pattern.
<31> The above-mentioned <19>, wherein the light irradiation means includes a plurality of lasers, a multimode optical fiber, and a collective optical system that condenses the laser beams emitted from the plurality of lasers and couples the laser beams to the multimode optical fiber. > To <30>. The method for forming a permanent pattern according to any one of <30>.
In the method for forming a permanent pattern according to <31>, the light irradiation unit collects the laser beams respectively irradiated from the plurality of lasers by the collective optical system and can be coupled to the multimode optical fiber. By doing so, exposure is performed with exposure light having a deep focal depth. As a result, the exposure to the photosensitive solder resist layer is performed with extremely high definition. Thereafter, the photosensitive solder resist layer is developed to form a very fine permanent pattern.
<32> The method for forming a permanent pattern according to any one of <14> to <31>, wherein the exposure is performed using a laser beam having a wavelength of 395 to 415 nm.
<33> The method for forming a permanent pattern according to any one of <14> to <32>, wherein after the development is performed, the photosensitive solder resist layer is cured.
In the method for forming a permanent pattern according to <33>, after the development, the curing treatment is performed on the photosensitive solder resist layer. As a result, the film strength of the cured region of the photosensitive solder resist layer is increased.
<34> The method for forming a permanent pattern according to <33>, wherein the curing treatment is at least one of a whole surface exposure treatment and a whole surface heat treatment performed at 120 to 200 ° C.
In the permanent pattern forming method according to <34>, curing of the resin in the photosensitive solder resist composition is promoted in the entire surface exposure process. Moreover, the film | membrane intensity | strength of a cured film is raised in the whole surface heat processing performed on the said temperature conditions.
<35> The method for forming a permanent pattern according to any one of <14> to <34>, wherein at least one of a protective film, an interlayer insulating film, and a solder resist pattern is formed.
In the permanent pattern forming method according to <35>, at least one of a protective film, an interlayer insulating film, and a solder resist pattern is formed. Protected from impact and bending.

<36> A permanent pattern formed by the method for forming a permanent pattern according to any one of <14> to <35>.
Since the permanent pattern according to <36> is formed by the permanent pattern forming method, it has excellent chemical resistance, surface hardness, heat resistance, and the like, and has high definition and multilayer wiring of semiconductors and parts. This is useful for high-density mounting on boards and build-up wiring boards.
<37> The permanent pattern according to <36>, which is at least one of a protective film, an interlayer insulating film, and a solder resist pattern.
Since the permanent pattern according to <37> is at least one of a protective film, an interlayer insulating film, and a solder resist pattern, the wiring may be subjected to an impact or bending from the outside depending on the insulating property, heat resistance, etc. of the film. Protected from.

According to the present invention, conventional problems can be solved, and when used as a photosensitive solder resist layer of a photosensitive solder resist film, the surface tackiness of the photosensitive solder resist layer is small, and the support and It is possible to provide a photosensitive solder resist composition excellent in the peelability of the protective film.
In addition, according to the present invention, in the blue-violet laser exposure system, high sensitivity, excellent adhesion to the substrate, excellent storage stability, excellent insulation after development, heat resistance, chemical resistance, surface hardness, etc. A photosensitive solder resist composition suitable as a photosensitive solder resist layer of a photosensitive solder resist film from which a cured film having a high molecular weight is obtained, a photosensitive solder resist film using the same, and a high-definition permanent pattern (protective film, interlayer) An insulating film, a solder resist pattern, and the like) and an efficient formation method thereof.

(Photosensitive solder resist composition)
The photosensitive solder resist composition of the present invention comprises a (meth) acrylamide copolymer, an alkali-soluble photocrosslinkable resin, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, a thermosetting accelerator, A coloring agent, preferably an inorganic filler, and further other components appropriately selected as necessary.

<(Meth) acrylamide copolymer>
As long as the (meth) acrylamide copolymer (excluding those having a self-condensable group) has an acid value of 90 to 200 mgKOH / g and a mass average molecular weight of 30,000 to 80,000, Although there is no restriction | limiting in particular, Preferably the thing whose glass transition temperature (Tg) is 420K or more is mentioned further.
Here, as the self-condensable group, hydroxymethyl group, methoxymethyl group, ethoxymethyl group, n-propoxymethyl group, isopropoxymethyl group, n-butoxymethyl group, isobutoxymethyl group, sec-butoxymethyl group And tert-butoxymethyl group.
In this specification, when referring to both or one of “acrylic and methacrylic”, it may be expressed as “(meth) acrylic”.

The acid value of the (meth) acrylamide copolymer is the mass (g) of potassium hydroxide necessary to neutralize the acidity of the carboxylic acid in 1 g of the (meth) acrylamide copolymer. Accordingly, it can be measured by a conventional neutralization titration method.
As described above, the acid value is 90 to 200 mgKOH / g, preferably 95 to 180 mgKOH / g. If the acid value is less than 90 mgKOH / g, the developability of the unexposed resist may be inferior, and if it exceeds 200 mgKOH / g, the pattern cross-sectional shape, adhesion, pencil hardness, and gold plating resistance may be inferior. is there.

  As above-mentioned, as a mass mean molecular weight of the said (meth) acrylamide copolymer, it is 30,000-80,000, Preferably it is 40,000-70,000. When the mass average molecular weight is less than 3,000, the heat resistance of the cured resist may be inferior, and when it exceeds 80,000, the developability may be inferior.

  As described above, the glass transition temperature (Tg) of the (meth) acrylamide copolymer is preferably 420 K or higher, and more preferably 430 to 450 K. When the glass transition temperature (Tg) is less than 420K, the peelability of the support or the protective film may be inferior.

Specifically, the (meth) acrylamide copolymer is preferably a copolymer represented by the following general formula (I).
However, in general formula (I), R ¹ represents hydrogen or a methyl group, R ² represents at least one of alkoxycarbonyl and an optionally substituted aryl group (wherein the substituent does not include a self-condensable group). R ³ represents an alkyl group, an alkyl group that may be substituted (provided that the substituent does not include a self-condensable group), an aryl group, or an aryl group that may be substituted (provided that the substituent) Represents a self-condensable group).
Moreover, x, y, and z represent the mass composition ratio of a repeating unit, and are x: y: z = 15-30: 20-60: 25-50, and x + y + z = 100.
The x component is specifically acrylic acid or methacrylic acid.
The y component is at least one of alkyl (meth) acrylate and styrene. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) Acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, heptyl (meth) acrylate, Octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, styrene, α-methylstyrene, m-chloromethylstyrene, p-methoxystyrene, p-chlorostyrene, p-bromostyrene Emissions, m- methoxystyrene, p- hydroxystyrene, and the like.
The z component is N-mono-substituted (meth) acrylamide, preferably a compound having a homopolymer Tg of 400K or more, specifically, N-tert-butylacrylamide, N-4- Butoxycarbonylphenyl methacrylamide, N-isopropylmethacrylamide, N-sec-butylmethacrylamide, N-tert-butylmethacrylamide, N-4-ethoxycarbonylphenylmethacrylamide, N-4-methoxycarbonylphenylmethacrylamide, etc. Can be mentioned.

Among the copolymers represented by the general formula (I), a copolymer represented by the following general formula (II) is preferable from the viewpoint of excellent protective film peelability and particularly excellent properties as a solder resist. Particularly preferred.
However, in said general formula (II), R < ¹ >, R < ² > and R < ³ > are the same as that of the said general formula (I).
R ⁴ represents an alkyl group, an optionally substituted alkyl group, an aryl group or an optionally substituted aryl group (however, the substituent does not include a self-condensable group), and R ⁵ represents a hydrogen atom, a halogen atom An atom, an alkyl group or an alkoxy group is represented.
^{Also, x, y} 1, y ² and z represent weight compositional ratio of the repeating ^{units, x: y 1: y 2} : z = 15~30: 0~60: 0~60: a 25 to 50, y ¹ + ^y 2 = ^20~60, an ^{x + y 1 + y 2 +} z = 100.
Preferable specific examples of the y ¹ component and the y ² component are the same as the y component described in the general formula (I). Particularly preferable examples of the y ¹ component include methyl methacrylate and y ² component. May include styrene.

-Synthesis of (meth) acrylamide copolymer-
The method for synthesizing the N-monosubstituted acrylic or methacrylamide copolymer is not particularly limited, and can be synthesized by ordinary radical polymerization. Examples of the polymerization method include a solution polymerization method and a bulk polymerization method. Usually, a solution polymerization method is often used.
There is no restriction | limiting in particular as a solvent used in the said solution polymerization method, Although it can select suitably according to the objective, For example, Alcohol solvents, such as water, methanol, ethanol, etc .; Ketone type, such as acetone and methyl ethyl ketone Solvents; ether solvents such as tetrahydrofuran and dioxane; diol monoalkyl ether acetate solvents such as methoxypropyl acetate; aromatic solvents such as benzene and toluene; These solvents may be used individually by 1 type, and 2 or more types may be mixed and used for them.
There is no restriction | limiting in particular as a monomer density | concentration in the said solution polymerization, Although it can select suitably according to the objective, 1-90 mass% is preferable and 10-70 mass% is more preferable.

The radical polymerization method is arbitrarily selected from generally known methods such as radiation irradiation, electron beam irradiation, heating in the presence of a radical polymerization initiator, and light irradiation in the presence of a photosensitizer. be able to.
The radical polymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose. For example, azobisisobutyronitrile, 2,2-azobis-2,4-dimethylvaleronitrile, azobis Azo initiators such as cyclohexanecarbonitrile, methyl azobisisobutyrate, azobisisobutylamidine hydrochloride, azobiscyanovaleric acid, etc .; persulfate initiators such as ammonium persulfate, sodium persulfate, etc .; benzoyl peroxide, cumene hydroperoxide , Etc .; redox initiators such as ammonium persulfate-sodium sulfite; and the like.
The amount of these radical polymerization initiators used is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 3 parts by mass per 100 parts by mass of the monomer. The polymerization temperature varies depending on the polymerization initiation method and the type of initiator used, but is usually in the range of 10 to 100 ° C., preferably 40 to 80 ° C.
The (meth) acrylamide copolymer obtained as described above is preferably purified by isolation, dialysis, ultrafiltration or the like according to a conventional method in order to remove unreacted monomers and the like.

  As content in the said photosensitive composition of the said (meth) acrylamide copolymer, 15-50 mass% of alkali-soluble photocrosslinkable resin is preferable, and 25-40 mass% is more preferable. When the content is less than 15% by mass, the effect of improving the peelability of the support and the protective film may not be sufficiently exhibited. When the content exceeds 50% by mass, the pencil hardness of the cured film may be inferior. This (meth) acrylamide copolymer may be used individually by 1 type, and may use 2 or more types together.

<Alkali-soluble photocrosslinkable resin>
The alkali-soluble photocrosslinkable resin has a function as a binder, and has a function of increasing the hardness of the first photosensitive solder resist layer and adding properties as an elastic body.
The alkali-soluble refers to the property that the photosensitive solder resist composition containing it is dissolved by an alkaline developer, and specifically, if it is soluble to the extent that the desired development processing is performed. Good. The alkaline developer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alkali metal hydroxides such as sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, hydroxyethylamine, triethylamine Or an aqueous solution of a quaternary ammonium hydroxide such as tetramethylammonium hydroxide or a mixture thereof with a miscible organic solvent. pH is 8-14 and 0.01-10 mass% aqueous solution of these alkali agents is preferable. Among these alkaline developers, in the printed wiring board industry, 0.2 to 2 mass% sodium carbonate aqueous solution is generally used, and 1 mass% sodium carbonate aqueous solution is the most common.
As an example of the development method, the photosensitive solder resist layer is pressure-bonded using a laminator while the surface is leveled and the protective film of the photosensitive solder resist film is peeled off on the surface of the dried copper clad laminate. Then, a laminate comprising a copper-clad laminate, a photosensitive solder resist layer, and a support film is prepared. The pressure bonding conditions are a laminate temperature of 70 ° C., a pressure roll temperature of 105 ° C., a pressure roll pressure of 3 kg / cm ^2, and a pressure bonding speed of 1.2 m / min.
The support film is peeled off from the laminate, and a 1 mass% sodium carbonate aqueous solution at 30 ° C. is sprayed at a pressure of 0.1 MPa over the entire surface of the photosensitive solder resist layer on the copper-clad laminate. If the photosensitive solder resist layer on the copper clad laminate is removed after spraying for at least 60 seconds, it will be developed.
Such an alkali-soluble resin can be suitably selected from those showing a solubility of 1% by mass or more in a 1% by mass sodium carbonate aqueous solution at 30 ° C., for example.
The photocrosslinking property refers to a property of changing a linear polymer molecule into a network having a three-dimensional network structure by photochemical reaction. Specifically, free radicals generated by photolysis of a photopolymerization initiator are used. It refers to a polymer that can be networked by polymerization reaction.

The alkali-soluble photocrosslinkable resin is a resin that is soluble in a 1% aqueous sodium carbonate solution (pH = 10) containing an alkali-soluble group and a crosslinkable group involved in photopolymerization in the molecule.
There is no restriction | limiting in particular as said alkali-soluble photocrosslinkable resin, According to the objective, it can select suitably, For example, a vinyl polymer type photocrosslinkable resin, an epoxy resin ester type photocrosslinkable resin, etc. are mentioned.

-Vinyl polymer type photocrosslinkable resin-
The vinyl polymer photocrosslinkable resin is classified into the following types (A-1), (A-2) and (A-3), and is selected from at least one of the types.
Type (A-1): produced by reaction of (a) a carboxyl group-containing copolymer resin and (b) an epoxy group-containing unsaturated compound.
Type (A-2): (c) An epoxy group-containing copolymer resin and (d) a carboxyl group-containing unsaturated compound are subjected to an addition reaction, and (e) a polybasic acid anhydride is converted into a hydroxyl group of the resulting product. Produced by addition reaction.
Type (A-3): produced by addition reaction of (f) a copolymer resin containing an acid anhydride group and (g) a compound having one hydroxyl group and at least one (meth) acryloyl group in the molecule. The

-Type (A-1)-
The (a) carboxyl group-containing copolymer resin used for the production of the vinyl polymer type photocrosslinkable resin of the type (A-1) is one unsaturated group and at least one carboxyl group in one molecule or It is obtained by copolymerizing a compound having an acid anhydride group and at least one of (meth) acrylic acid ester and styrenes.

  The compound (a) having one unsaturated group and at least one carboxyl group or acid anhydride group in one molecule having the carboxyl group-containing copolymer resin as a structural unit is (meth) acrylic acid, Include those containing two or more carboxyl groups in the molecule, such as maleic acid and itaconic acid. Also included are maleic acid, itaconic acid monoesters, or monoamides. Moreover, the half ester compound which is a reaction product of a hydroxyl group containing (meth) acrylate and a saturated or unsaturated dibasic acid anhydride is mentioned. These half ester compounds can be obtained by reacting a hydroxyl group-containing (meth) acrylate with a saturated or unsaturated dibasic acid anhydride in an equimolar ratio.

  Examples of the hydroxyl group-containing acrylate used in the synthesis of the half ester compound include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, and trimethylolpropane. Examples include di (meth) acrylate, pendaerythritol tri (meth) acrylate, diventaerythritol penta (meth) acrylate, and the like.

Examples of the saturated or unsaturated dibasic acid anhydride used in the synthesis of the half ester compound include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyl nadrahydrophthalic anhydride, ethyl tetrahydro Examples thereof include phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride and the like. Of these, (meth) acrylic acid is preferred.
These compounds having one unsaturated group and at least one carboxyl group or acid anhydride group in one molecule may be used alone or in combination of two or more.

  Examples of the (meth) acrylic acid ester that constitutes the structural unit of the carboxyl group-containing copolymer resin include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and isopropyl (meth). Acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, 2-ethylhexyl (Meth) acrylate, t-octyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, acetoxyethyl (meth) acrylate, phenyl (meth) acrylate, 2-hydroxyethyl (meth) Acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (2-methoxyethoxy) ethyl (meth) acrylate, 3-phenoxy-2-hydroxypropyl (meth) acrylate, benzyl (meta ) Acrylate, diethylene glycol monomethyl ether (meth) acrylate, diethylene glycol monoethyl ether (meth) acrylate, diethylene glycol monophenyl ether (meth) acrylate, triethylene glycol monomethyl ether (meth) acrylate, triethylene glycol monoethyl ether (meth) acrylate, Polyethylene glycol monomethyl ether (meth) acrylate, polyethylene glycol monoethyl ether (meth) acrylate , Β-phenoxyethoxyethyl acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, trifluoroethyl (meta ) Acrylate, octafluoropentyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, tribromophenyl (meth) acrylate, tribromophenyloxyethyl (meth) acrylate, and the like.

Examples of the styrenes constituting the structural unit of the carboxyl group-containing copolymer resin (a) include, for example, styrene, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, hydroxystyrene, methoxystyrene, Butoxystyrene, acetoxystyrene, chlorostyrene, dichlorostyrene, bromostyrene, chloromethylstyrene, hydroxystyrene protected with a group that can be deprotected by an acidic substance (for example, t-Boc, etc.), methyl vinylbenzoate, α-methyl Examples include styrene.
The (a) carboxyl group-containing copolymer resin comprises a compound having one unsaturated group and at least one carboxyl group or acid anhydride group in one molecule, a (meth) acrylic acid ester monomer, and styrene. It is obtained by copolymerization by a usual copolymerization method with at least one of the above classes, for example, a solution polymerization method.
In addition, (a) maleic acid monoester / styrene copolymers, maleic acid monoamide / styrene copolymers, itaconic acid monoester / styrene copolymers, and itacon included in the carboxyl group-containing copolymer resin. In the case of acid monoamide / styrene copolymers, obtain by polymer reaction of maleic anhydride / styrene copolymers or itaconic anhydride / styrene copolymers with alcohols or primary or secondary amines, respectively. Can do.

Examples of the alcohols used for the polymer reaction with the maleic anhydride include methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, pentanol, hexanol, and cyclohexanol. Preferable examples include methoxyethanol, ethoxyethanol, methoxypropanol, ethoxypropanol and the like.
Examples of the primary amines include benzylamine, phenethylamine, 3-phenyl-1-propylamine, 4-phenyl-1-butylamine, 5-phenyl-1-pentylamine, and 6-phenyl-1-hexylamine. , Α-methylbenzylamine, 2-methylbenzylamine, 3-methylbenzylamine, 4-methylbenzylamine, 2- (p-tolyl) ethylamine, β-methylphenethylamine, 1-methyl-3-phenylpropylamine, 2- Chlorobenzylamine, 3-chlorobenzylamine, 4-chlorobenzylamine, 2-fluorobenzylamine, 3-fluorobenzylamine, 4-fluorobenzylamine, 4-bromophenethylamine, 2- (2-chlorophenyl) ethylamine, 2- (3-Chlorophenyl) ethyl Amine, 2- (4-chlorophenyl) ethylamine, 2- (2-fluorophenyl) ethylamine, 2- (3-fluorophenyl) ethylamine, 2- (4-fluorophenyl) ethylamine, 4-fluoro-α, α-dimethyl Phenethylamine, 2-methoxybenzylamine, 3-methoxybenzylamine, 4-methoxybenzylamine, 2-ethoxybenzylamine, 2-methoxyphenethylamine, 3-methoxyphenethylamine, 4-methoxyphenethylamine, methylamine, ethylamine, isopropylamine, n -Propylamine, n-butylamine, tert-butylamine, sec-butylamine, pentylamine, hexylamine, cyclohexylamine, heptylamine, octylamine, laurylamine, phenylamine, 1 Naphthylamine, methoxymethylamine, 2-methoxyethylamine, 2-ethoxyethylamine, 3-methoxypropylamine, 2-butoxyethylamine, 2-cyclohexyloxyethylamine, 3-ethoxypropylamine, 3-propoxypropylamine, 3- Preferable examples include isopropoxypropylamine.
Further, examples of the secondary amines preferably include dimethylamine, diethylamine, methylethylamine, methylpropylamine, diethylamine, ethylpropylamine, dipropylamine, dibutylamine, N, N-methylbenzylamine and the like. Can do.

-(B) Epoxy group-containing unsaturated compound-
The (b) epoxy group-containing unsaturated compound used for the production of the vinyl polymer type photocrosslinkable resin of the type (A-1) includes one radical polymerizable unsaturated group and an epoxy group in one molecule. Any compound may be used, and examples thereof include compounds represented by the following general formulas (III-1) to (III-14).

However, in the general formula (III-1) ~ (III -14), R 14 is a hydrogen atom or a methyl _{group, R 15} is an alkylene group having 1 to 10 carbon _{atoms, R 16} is a hydrocarbon group having 1 to 10 carbon atoms , P represents 0 or an integer of 1-10.
These (b) epoxy group-containing unsaturated compounds may be used alone or in admixture of two or more. Among these, glycidyl (meth) acrylate and 3,4-epoxycyclohexylmethyl (meth) acrylate are preferable.

-Type (A-2)-
The epoxy group-containing copolymer resin (c) used in the production of the vinyl polymer type photocrosslinkable resin of the type (A-2) is a non-reactive (meth) acrylic with an epoxy group-containing monomer and other epoxy groups. It can be obtained by copolymerization with esters and / or styrenes.
As the epoxy group-containing monomer, the compounds described above in the description of the vinyl polymer type photocrosslinkable resin of type (A-1) are preferably used.
At least one of (meth) acrylic acid esters and styrenes that are non-reactive with epoxy groups is a carboxyl group, an alcoholic hydroxyl group, or phenol among the above-mentioned photocrosslinkable resins of type (A-1). Those which do not contain a functional hydroxyl group, an amino group or the like are preferably used.
As a production method, it is obtained by copolymerizing an epoxy group-containing monomer, a non-reactive (meth) acrylic acid ester and styrene with a conventional method such as a solution polymerization method.
Here, the molar ratio of the epoxy group-containing monomer and the (meth) acrylic ester non-reactive with other epoxy groups and at least one of styrenes is preferably 60:40 to 20:80. If the amount of the epoxy group-containing monomer is too small and the molar ratio is larger than 20:80, the amount of addition of the next unsaturated carboxylic acid and polybasic acid anhydride to the copolymer is reduced. If the molar ratio is less than 60:40, the softening point tends to be too low.
Further, the carboxyl group-containing unsaturated compound (d) is one unsaturated group and at least one carboxyl group or acid per molecule in the description of the vinyl polymer type photocrosslinkable resin of type (A-1). As the compound having an anhydride group, the aforementioned compounds can be preferably used.
Further, as the polybasic acid anhydride (e), maleic anhydride, succinic anhydride, hexahydrophthalic anhydride, 3-methylhexahydrophthalic anhydride, 4-methylhexahydrophthalic anhydride, 3-ethylhexahydrophthalic anhydride, 4-ethylhexahydrophthalic anhydride, tetrahydrophthalic anhydride, 3-methyltetrahydrophthalic anhydride, 4-methyltetrahydrophthalic anhydride, 3-ethyltetrahydrophthalic acid Saturated or unsaturated aliphatic, alicyclic or aromatic compounds having one acid anhydride group in the molecule, such as anhydride, 4-ethyltetrahydrophthalic anhydride and phthalic anhydride are preferred. Among these, tetrahydrophthalic anhydride is particularly preferable.
The reaction of the epoxy group-containing copolymer, the carboxyl group-containing unsaturated compound and the subsequent polybasic acid anhydride is preferably carried out as follows. After addition reaction of 0.8 to 1.2 mol of unsaturated carboxylic acid per one epoxy group equivalent of the copolymer to the epoxy group-containing monomer copolymer, Polybasic acid anhydride is subjected to addition reaction.

-Type (A-3)-
The acid anhydride group-containing resin (f) used for the production of the vinyl polymer type photocrosslinkable resin of type (A-3) is a copolymer of maleic anhydride and styrene or itaconic anhydride and styrene. Obtained by copolymerization.
As the styrene as the copolymer component, those already described in the description of the photocrosslinkable resin of the type (A-1) are preferably used. The copolymer composition ratio of maleic anhydride or itaconic anhydride and styrenes is preferably 90:10 to 10:90, more preferably 80:20 to 20:80, and particularly preferably 70:30 to 30:70. When it is 90:10 or more, the development resistance of the cured portion is inferior, and when it is 10:90 or less, the developability is inferior.
A copolymer having a mass average molecular weight of about 1,000 to 5,000 obtained by copolymerizing styrene at a ratio of 1 mol to 3 mol with respect to 1 mol of maleic anhydride is preferable. For example, ARCO Chemical Company Examples thereof include SMA ranges 1000, 2000, and 3000.

  Examples of the compound (g) having one hydroxyl group and at least one (meth) acryloyl group in the molecule include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl. (Meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, polycaprolactone mono (meth) acrylate, pendaerythritol tri (meth) acrylate, trimethylolpropane di (meth) acrylate, neopentyl glycol mono (Meth) acrylate, 1,6-hexanediol mono (meth) acrylate, mono (2- (meth) acryloyloxyethyl) acid phosphate, di (2- (meth) acryloyloxyethyl) ) Acid phosphate, glycerol di (meth) acrylate.

The ring-opening addition reaction of the acid anhydride copolymer and a monomer having one hydroxyl group and at least one (meth) acryloyl group in the molecule is performed in an organic solvent containing no active hydrogen. It can be manufactured by the method. Preferred solvents are ethyl acetate, methoxypropyl acetate, methyl ethyl ketone and the like. In this case, the molar ratio of hydroxyl group in the monomer / acid anhydride group in the copolymer is preferably 0.8 to 1.2. The ring-opening addition reaction is usually carried out at 50 ° C. to 200 ° C. In order to prevent gelation, about 80 to 150 ° C. is preferable. As reaction accelerators, tertiary amines such as triethylamine, triethanolamine, morpholine, and pentamethyldiethylenetriamine, or quaternary ammonium salts can be used. On the other hand, a known polymerization inhibitor such as hydroquinone, hydroquinone monomethyl ether, t-butylhydroquinone, t-butylcatechol, benzoquinone, phenothiazine and the like can be added and used in order to prevent the formation of a polymer during the reaction.

As described above, the vinyl polymer photocrosslinkable resin comprising at least one of the types (A-1), (A-2) and (A-3) obtained has an acid value of 50 to 250 mgKOH. / G is required.
The acid value is more preferably from 70 to 200 mgKOH / g, particularly preferably from 90 to 180 mgKOH / g. When the acid value is less than 50 mgKOH / g, it is difficult to remove the unexposed area with a developing solution that is a weak alkaline aqueous solution. There are harmful effects. The vinyl polymer photocrosslinkable polymer (A) preferably has a mass average molecular weight in the range of 5,000 to 200,000. The mass average molecular weight is more preferably 10,000 to 100,000, and particularly preferably 30,000 to 80,000. When the mass average molecular weight is less than 5,000, the dryness to touch is remarkably inferior and the peelability from the support is inferior. On the other hand, a mass average molecular weight exceeding 200,000 is not preferable because problems such as removability of unexposed portions and storage stability due to an alkaline developer are caused.
The solid content of the alkali-soluble photocrosslinkable resin in the total solid content of the photosensitive solder resist layer is preferably 15 to 70% by mass. If it is less than 15% by mass, the toughness of the cured film is inferior, and if it exceeds 70% by mass, the balance of performance deteriorates such as a decrease in reliability.
In particular, one mixture from the types (A-1) to (A-3) and one mixture from the epoxy resin ester-type photocrosslinkable oligomer described later are preferable because they can provide balanced performance. In this case, the mixing ratio is 10/90 to 90/10 by mass. 20/80 to 80/20 are more preferable, and 30/70 to 70/30 are particularly preferable.

-Epoxy resin ester type photocrosslinkable resin-
The epoxy resin ester-type photocrosslinkable resin is not particularly limited and may be appropriately selected depending on the purpose. For example, (h) an epoxy resin and (i) one unsaturated group in one molecule It produces | generates by further reacting (j) polybasic acid anhydride with the esterification reaction product with the compound which has at least 1 carboxyl group or acid anhydride group.
Examples of the epoxy resin (h) include YDCN-701, YDCN-704 manufactured by Toto Kasei Co., Ltd .; N-665, N-680, N-695 manufactured by Dainippon Ink & Chemicals, Inc .; Nippon Kayaku Co., Ltd. EOCN-102, EOCN-104 manufactured by Asahi Kasei Kogyo Co., Ltd. ECN-265, ECN-293, ECN-285, ECN-299 and other cresol novolac type epoxy resins, and Toto Kasei K.K. -602; DEN-431, DEN-438, DEN-439 manufactured by Dow Chemical Japan Co., Ltd .; EPN-1138, EPN-1235, EPN-1299 manufactured by Ciba Specialty Chemicals Co., Ltd .; Phenol novolac type epoxy resins such as N-730 and N-770 manufactured by the same company may be mentioned. In addition, a part of the novolac type epoxy resin is, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, bixylenol type epoxy resin, trishydroxyphenylmethane type epoxy resin, tetra Epoxy resins such as phenylethane type epoxy resins, alicyclic epoxy resins, salicylaldehyde type epoxy resins and the like can also be used advantageously.

Next, the compound (i) having one unsaturated group and at least one carboxyl group or acid anhydride group in one molecule is described for the vinyl polymer type photocrosslinkable resin of the type (A-1). Of these, the aforementioned compounds can be preferably used.
Similarly, the polybasic acid anhydride (j) may use the above-mentioned compounds as the component (e) in the description of the vinyl polymer type photocrosslinkable resin of the type (A-2).

--Method for producing epoxy resin ester type photocrosslinkable resin--
There is no restriction | limiting in particular as a manufacturing method of the said epoxy resin ester type photocrosslinkable resin, According to the objective, it can select suitably, For example, the epoxy resin (h) in the case of manufacture, and 1 piece in 1 molecule In the reaction of the unsaturated group with the compound (i) having at least one carboxyl group or acid anhydride group, one unsaturated group per molecule for one equivalent of the epoxy group of the epoxy resin (h) And the compound (i) having at least one carboxyl group or acid anhydride group are preferably reacted at a ratio of 0.8 to 1.05 equivalent, more preferably 0.9 to 1.0 equivalent.
The epoxy resin (h) and the compound (i) having one unsaturated group and at least one carboxyl group or acid anhydride group in one molecule are dissolved and reacted in an organic solvent. For example, ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl Glycol ethers such as ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate, fats such as octane and decane Hydrocarbons, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and petroleum solvents such as solvent naphtha.

Furthermore, it is preferable to use a catalyst to accelerate the reaction. Examples of the catalyst used include triethylamine, benzylmethylamine, methyltriethylammonium chlorite, benzyltrimethylammonium chlorite, benzyltrimethylammonium bromide, benzyltrimethylmethylammonium iodide, triphenylphosphine, and the like. The amount of the catalyst used is preferably 0.1 to 10 parts by mass with respect to a total of 100 parts by mass of the epoxy resin and the vinyl group-containing monocarboxylic acid (b).
Further, it is preferable to use a polymerization inhibitor for preventing polymerization during the reaction. Examples of the polymerization inhibitor include hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, and the amount used is 100 parts by mass in total of the epoxy resin (a) and the vinyl group-containing monocarboxylic acid (b). The amount is preferably 0.01 to 1 part by mass. The reaction temperature is preferably 60 to 150 ° C, more preferably 80 to 120 ° C.

  The epoxy resin ester-type photocrosslinkable resin is obtained by reacting the reaction product thus obtained with a polybasic acid anhydride (j). The reaction temperature between the reaction product and the polybasic acid anhydride (c) is preferably 60 to 120 ° C.

The acid value of the epoxy resin ester type photocrosslinkable resin is adjusted by reacting 0.1 to 1.0 equivalent of polybasic acid anhydride (j) with respect to 1 equivalent of hydroxyl group in the reaction product. it can. The acid value of the epoxy resin ester type photocrosslinkable resin is preferably 30 to 150 mgKOH / g, and more preferably 50 to 120 mgKOH / g. When the acid value is less than 30 mgKOH / g, the solubility of the photocurable resin composition in a dilute alkali solution is lowered, and when it exceeds 150 mgKOH / g, the electric characteristics of the cured film tend to be lowered.
The epoxy resin ester type photocrosslinkable resin preferably has a mass average molecular weight of 500 to 5,000, more preferably 1,000 to 4,000, and particularly preferably 1,500 to 3,500. If it is 500 or less, the adhesiveness is too high, and it becomes difficult to peel off the protective film, and if it exceeds 5,000, it becomes difficult to produce the resin.

<Polymerizable compound>
The polymerizable compound is not particularly limited and may be appropriately selected depending on the purpose. The compound has at least one addition-polymerizable group in the molecule and has a boiling point of 100 ° C. or higher at normal pressure. For example, at least one selected from monomers having a (meth) acryl group is preferable.

  There is no restriction | limiting in particular as a monomer which has the said (meth) acryl group, According to the objective, it can select suitably, For example, polyethyleneglycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) ) Monofunctional acrylates and monofunctional methacrylates such as acrylates; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, trimethylolpropane diacrylate, neopentylglycol di (Meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hex (Meth) acrylate, dipentaerythritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanurate, tri (acryloyloxyethyl) cyanurate, Polyfunctional alcohols such as glycerin tri (meth) acrylate, trimethylolpropane, glycerin, bisphenol, and the like, and (meth) acrylated after addition reaction of ethylene oxide or propylene oxide, Japanese Patent Publication No. 48-41708, Japanese Patent Publication Urethane acrylates described in publications such as JP 50-6034 and JP 51-37193; JP 48-64183, JP 49-4319 Polyester acrylates described in various publications such as JP, JP 30-30490, and polyfunctional acrylates and methacrylates such as epoxy acrylates which are reaction products of an epoxy resin and (meth) acrylic acid. It is done. Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta (meth) acrylate are particularly preferable.

  5-75 mass% is preferable and, as for solid content in the said photosensitive soldering resist composition solid content of the said polymeric compound, 10-40 mass% is more preferable. If the solid content is less than 5% by mass, problems such as deterioration of developability and reduction in exposure sensitivity may occur. If it exceeds 75% by mass, the adhesiveness of the photosensitive solder resist layer becomes strong. This is not preferable.

<Photopolymerization initiator>
The photopolymerization initiator is not particularly limited as long as it has the ability to initiate polymerization of the polymerizable compound, and can be appropriately selected from known photopolymerization initiators, for example, visible from the ultraviolet region. Those having photosensitivity to light are preferable, and may be an activator that generates an active radical by causing some action with a photoexcited sensitizer, and initiates cationic polymerization according to the type of monomer. It may be an initiator.
The photopolymerization initiator preferably contains at least one component having a molecular extinction coefficient of at least about 50 within a range of about 300 to 800 nm (more preferably 330 to 500 nm).

  Examples of the photopolymerization initiator include halogenated hydrocarbon derivatives (for example, those having a triazine skeleton, those having an oxadiazole skeleton, those having an oxadiazole skeleton), phosphine oxide, hexaarylbiimidazole, Examples include oxime derivatives, organic peroxides, thio compounds, ketone compounds, aromatic onium salts, and ketoxime ethers.

  Examples of the halogenated hydrocarbon compound having a triazine skeleton include those described in Wakabayashi et al., Bull. Chem. Soc. Japan, 42, 2924 (1969), a compound described in British Patent 1388492, a compound described in JP-A-53-133428, a compound described in German Patent 3337024, F.I. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964), compounds described in JP-A-62-258241, compounds described in JP-A-5-281728, compounds described in JP-A-5-34920, US Pat. No. 4,221,976 And the compounds described in the book.

  Wakabayashi et al., Bull. Chem. Soc. As a compound described in Japan, 42, 2924 (1969), for example, 2-phenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-chlorophenyl) -4,6 -Bis (trichloromethyl) -1,3,5-triazine, 2- (4-tolyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxyphenyl)- 4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2,4-dichlorophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2, 4,6-tris (trichloromethyl) -1,3,5-triazine, 2-methyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2-n-nonyl-4,6- Bis (trichloromethyl) 1,3,5-triazine, and 2-(alpha, alpha, beta-trichloroethyl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

Examples of the compound described in the British Patent 1388492 include 2-styryl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methylstyryl) -4,6- Bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxystyryl)- 4-amino-6-trichloromethyl-1,3,5-triazine and the like can be mentioned.
Examples of the compounds described in JP-A-53-133428 include 2- (4-methoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2 -(4-Ethoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- [4- (2-ethoxyethyl) -naphth-1-yl]- 4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4,7-dimethoxy-naphth-1-yl) -4,6-bis (trichloromethyl) -1,3,5- Examples include triazine and 2- (acenaphtho-5-yl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

  Examples of the compound described in the specification of German Patent 3333724 include 2- (4-styrylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4 -Methoxystyryl) phenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (1-naphthylvinylenephenyl) -4,6-bis (trichloromethyl) -1,3,5 -Triazine, 2-chlorostyrylphenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-thiophen-2-vinylenephenyl) -4,6-bis (trichloromethyl)- 1,3,5-triazine, 2- (4-thiophene-3-vinylenephenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-furan-2 Vinylenephenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, and 2- (4-benzofuran-2-vinylenephenyl) -4,6-bis (trichloromethyl) -1,3 5-triazine etc. are mentioned.

  F. above. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964) include, for example, 2-methyl-4,6-bis (tribromomethyl) -1,3,5-triazine, 2,4,6-tris (tribromomethyl); -1,3,5-triazine, 2,4,6-tris (dibromomethyl) -1,3,5-triazine, 2-amino-4-methyl-6-tri (bromomethyl) -1,3,5- Examples include triazine and 2-methoxy-4-methyl-6-trichloromethyl-1,3,5-triazine.

  Examples of the compounds described in JP-A-62-258241 include 2- (4-phenylethynylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- Naphthyl-1-ethynylphenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4-tolylethynyl) phenyl) -4,6-bis (trichloromethyl) -1 , 3,5-triazine, 2- (4- (4-methoxyphenyl) ethynylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4-isopropylphenyl) Ethynyl) phenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4- (4-ethylphenylethynyl) phenyl) -4,6-bis (trichloromethyl) Le) -1,3,5-triazine.

  Examples of the compound described in JP-A-5-281728 include 2- (4-trifluoromethylphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2, 6-difluorophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (2,6-dichlorophenyl) -4,6-bis (trichloromethyl) -1,3,5- Examples include triazine, 2- (2,6-dibromophenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine.

  Examples of the compound described in JP-A-5-34920 include 2,4-bis (trichloromethyl) -6- [4- (N, N-diethoxycarbonylmethylamino) -3-bromophenyl] -1, 3,5-triazine, trihalomethyl-s-triazine compounds described in US Pat. No. 4,239,850, 2,4,6-tris (trichloromethyl) -s-triazine, 2- (4-chlorophenyl) Examples include -4,6-bis (tribromomethyl) -s-triazine.

  Examples of the compound described in US Pat. No. 4,221,976 include compounds having an oxadiazole skeleton (for example, 2-trichloromethyl-5-phenyl-1,3,4-oxadiazole, 2- Trichloromethyl-5- (4-chlorophenyl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (1-naphthyl) -1,3,4-oxadiazole, 2-trichloromethyl-5 -(2-naphthyl) -1,3,4-oxadiazole, 2-tribromomethyl-5-phenyl-1,3,4-oxadiazole, 2-tribromomethyl-5- (2-naphthyl) -1,3,4-oxadiazole; 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5- (4-chlorostyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (4-methoxystyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (1-naphthyl) -1, 3,4-oxadiazole, 2-trichloromethyl-5- (4-n-butoxystyryl) -1,3,4-oxadiazole, 2-tripromomethyl-5-styryl-1,3,4 Oxadiazole, etc.).

  Examples of the oxime derivative suitably used in the present invention include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutan-2-one, 3-propionyloxyiminobutan-2-one, and 2-acetoxy. Iminopentan-3-one, 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, 3- (4-toluenesulfonyloxy) iminobutane-2- ON, and 2-ethoxycarbonyloxyimino-1-phenylpropan-1-one.

Further, as photopolymerization initiators other than those described above, polyhalogen compounds (for example, 9-phenylacridine, 1,7-bis (9,9′-acridinyl) heptane, etc.), N-phenylglycine (for example, Carbon tetrabromide, phenyl tribromomethyl sulfone, phenyl trichloromethyl ketone, etc.), coumarins (for example, 3- (2-benzofuroyl) -7-diethylaminocoumarin, 3- (2-benzofuroyl) -7- (1-pyrrolidinyl) ) Coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-methoxybenzoyl) -7-diethylaminocoumarin, 3- (4-dimethylaminobenzoyl) -7-diethylaminocoumarin, 3,3′-carbonylbis (5 , 7-di-n-propoxycoumarin), 3,3′-carbonyl (7-diethylaminocoumarin), 3-benzoyl-7-methoxycoumarin, 3- (2-furoyl) -7-diethylaminocoumarin, 3- (4-diethylaminocinnamoyl) -7-diethylaminocoumarin, 7-methoxy-3 -(3-pyridylcarbonyl) coumarin, 3-benzoyl-5,7-dipropoxycoumarin, 7-benzotriazol-2-ylcoumarin, JP-A-5-19475, JP-A-7-271028, JP JP-A 2002-363206, JP-A 2002-363207, JP-A 2002-363208, JP-A 2002-363209, and the like, and amines (for example, ethyl 4-dimethylaminobenzoate). , 4-dimethylaminobenzoic acid n-butyl, 4-dimethyl Phenethyl aminobenzoate, 2-dimethylimidoethyl 4-dimethylaminobenzoate, 2-methacryloyloxyethyl 4-dimethylaminobenzoate, pentamethylenebis (4-dimethylaminobenzoate), phenethyl 3-dimethylaminobenzoate, pentamethylene Ester, 4-dimethylaminobenzaldehyde, 2-chloro-4-dimethylaminobenzaldehyde, 4-dimethylaminobenzyl alcohol, ethyl (4-dimethylaminobenzoyl) acetate, 4-piperidinoacetophenone, 4-dimethylaminobenzoin, N, N-dimethyl-4-toluidine, N, N-diethyl-3-phenidine, tribenzylamine, dibenzylphenylamine, N-methyl-N-phenylbenzylamine, 4-bromo-N, N-dimethyl Ruaniline, tridodecylamine, aminofluoranes (ODB, ODBII, etc.), crystal violet lactone, leuco crystal violet, etc., acylphosphine oxides (for example, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, Bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphenylphosphine oxide, Lucirin TPO, etc.), metallocenes (for example, bis (η ⁵ -2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, η ⁵ -cyclopentadienyl-η ⁶ -cumenyl-iron (1 +)-hexafluorophosphate (1-), etc.) JP, 53-133428, A JP, Sho 57-1819, JP-the 57-6096 and JP, US Patent compounds described in the 3,615,455 Patent specification mentioned.

  Examples of the ketone compound include benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 4-methoxybenzophenone, 2-chlorobenzophenone, 4-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, 2-ethoxycarbonylbenzolphenone, benzophenonetetracarboxylic acid or tetramethyl ester thereof, 4,4′-bis (dialkylamino) benzophenone (for example, 4,4′-bis (dimethylamino) benzophenone, 4,4′- Bisdicyclohexylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, 4,4′-bis (dihydroxyethylamino) benzophenone, 4-methoxy-4′-dimethylamino Nzophenone, 4,4'-dimethoxybenzophenone, 4-dimethylaminobenzophenone, 4-dimethylaminoacetophenone, benzyl, anthraquinone, 2-tert-butylanthraquinone, 2-methylanthraquinone, phenanthraquinone, xanthone, thioxanthone, 2-chloro -Thioxanthone, 2,4-diethylthioxanthone, fluorenone, 2-benzyl-dimethylamino-1- (4-morpholinophenyl) -1-butanone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino -1-propanone, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer, benzoin, benzoin ethers (for example, benzoin methyl ether, benzoin ethyl ether) Benzoin propyl ether, benzoin isopropyl ether, benzoin phenyl ether, benzyl dimethyl ketal), acridone, chloro acridone, N- methyl acridone, N- butyl acridone, N- butyl - such as chloro acrylic pyrrolidone.

In addition to the photopolymerization initiator, a sensitizer can be added for the purpose of adjusting the exposure sensitivity and the photosensitive wavelength in exposure to the photosensitive solder resist layer described later.
The sensitizer can be appropriately selected by a visible light, an ultraviolet laser, a visible light laser or the like as a light irradiation means described later.
The sensitizer is excited by active energy rays and interacts with other substances (eg, radical generator, acid generator, etc.) (eg, energy transfer, electron transfer, etc.) to thereby generate radicals, acids, etc. It is possible to generate a useful group of

  The sensitizer is not particularly limited and may be appropriately selected from known sensitizers. For example, known polynuclear aromatics (for example, pyrene, perylene, triphenylene), xanthenes (for example, Fluorescein, eosin, erythrosine, rhodamine B, rose bengal), cyanines (eg, indocarbocyanine, thiacarbocyanine, oxacarbocyanine), merocyanines (eg, merocyanine, carbomerocyanine), thiazines (eg, thionine, methylene blue) , Toluidine blue), acridines (eg, acridine orange, chloroflavin, acriflavine), anthraquinones (eg, anthraquinone), squariums (eg, squalium), acridones (eg, acridone, chloroacrid) N-methylacridone, N-butylacridone, N-butyl-chloroacridone (for example, 2-chloro-10-butylacridone, etc.), coumarins (for example, 3- (2-benzofuroyl)- 7-diethylaminocoumarin, 3- (2-benzofuroyl) -7- (1-pyrrolidinyl) coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-methoxybenzoyl) -7-diethylaminocoumarin, 3- (4- Dimethylaminobenzoyl) -7-diethylaminocoumarin, 3,3′-carbonylbis (5,7-di-n-propoxycoumarin), 3,3′-carbonylbis (7-diethylaminocoumarin), 3-benzoyl-7- Methoxycoumarin, 3- (2-furoyl) -7-diethylaminocoumarin, 3- (4-diethyl) Minocinnamoyl) -7-diethylaminocoumarin, 7-methoxy-3- (3-pyridylcarbonyl) coumarin, 3-benzoyl-5,7-dipropoxycoumarin and the like. 7-271028, JP 2002-363206, JP 2002-363207, JP 2002-363208, JP 2002-363209, and the like. It is done.

  Examples of the combination of the photopolymerization initiator and the sensitizer include, for example, an electron transfer start system described in JP-A-2001-305734 [(1) an electron donating initiator and a sensitizing dye, (2) A combination of an electron-accepting initiator and a sensitizing dye, (3) an electron-donating initiator, a sensitizing dye and an electron-accepting initiator (ternary initiation system)], and the like.

  As content of the said sensitizer, 0.05-30 mass% is preferable with respect to all the components in the said photosensitive soldering resist composition, 0.1-20 mass% is more preferable, 0.2-10 Mass% is particularly preferred. When the content is less than 0.05% by mass, the sensitivity to active energy rays is reduced, the exposure process takes time, and productivity may be reduced. The sensitizer may be precipitated from the photosensitive solder resist layer.

The said photoinitiator may be used individually by 1 type, and may use 2 or more types together.
Particularly preferred examples of the photopolymerization initiator include halogenated carbonization having the phosphine oxides, the α-aminoalkyl ketones, and the triazine skeleton, which can handle laser light having a wavelength of 405 nm in the later-described exposure. Examples include a composite photoinitiator, a hexaarylbiimidazole compound, or titanocene, which is a combination of a hydrogen compound and an amine compound as a sensitizer described later.

  As content in the said photosensitive soldering resist composition of the said photoinitiator, 0.5-20 mass% is preferable, 1-15 mass% is more preferable, 2-10 mass% is especially preferable.

<Thermal crosslinking agent>
There is no restriction | limiting in particular as said heat-crosslinking agent, According to the objective, it can select suitably, For example, an epoxy resin, a polyfunctional oxetane compound, etc. are mentioned suitably.
The epoxy resin and the polyfunctional oxetane compound are not particularly limited and may be appropriately selected depending on the intended purpose. For example, after curing of the photosensitive solder resist layer formed using the photosensitive solder resist composition In order to improve the film strength, an epoxy resin compound having at least two oxirane groups in one molecule, an oxetane compound having at least two oxetanyl groups in one molecule, etc. within a range that does not adversely affect developability and the like Can be used.

  There is no restriction | limiting in particular as said epoxy resin, According to the objective, it can select suitably, For example, a bixylenol type or a biphenol type epoxy resin ("YX4000; Japan Epoxy Resin Co., Ltd." etc.) or mixtures thereof, isocyania Heterocyclic epoxy resins having a nurate skeleton ("TEPIC; manufactured by Nissan Chemical Industries", "Araldite PT810; manufactured by Ciba Specialty Chemicals"), bisphenol A type epoxy resin, novolak type epoxy resin, bisphenol F type Epoxy resin, hydrogenated bisphenol A type epoxy resin, glycidylamine type epoxy resin, hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bisphenol S type epoxy resin, bisphenol A Borac type epoxy resin, tetraphenylolethane type epoxy resin, glycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, naphthalene group-containing epoxy resin (“ESN-190, ESN-360; manufactured by Nippon Steel Chemical Co., Ltd.”, “HP-4032” , EXA-4750, EXA-4700; manufactured by Dainippon Ink & Chemicals, Inc.), epoxy resins having a dicyclopentadiene skeleton (“HP-7200, HP-7200H; manufactured by Dainippon Ink & Chemicals, Inc.”), glycidyl Examples thereof include a methacrylate copolymer epoxy resin (“CP-50S, CP-50M; manufactured by NOF Corporation”), a copolymer epoxy resin of cyclohexylmaleimide and glycidyl methacrylate, and the like. These epoxy resins may be used individually by 1 type, and may use 2 or more types together.

  The polyfunctional oxetane compound is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include bis [(3-methyl-3-oxetanylmethoxy) methyl] ether and bis [(3-ethyl-3 -Oxetanylmethoxy) methyl] ether, 1,4-bis [(3-methyl-3-oxetanylmethoxy) methyl] benzene, 1,4-bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene, (3 -Methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate or oligomers thereof or In addition to polyfunctional oxetanes such as copolymers, oxetane groups and Novo And ether compounds with hydroxyl groups such as poly (p-hydroxystyrene), cardo-type bisphenols, calixarenes, calixresorcinarenes, silsesquioxanes, etc., and oxetane A copolymer of an unsaturated monomer having a ring and an alkyl (meth) acrylate is also included.

  There is no restriction | limiting in particular as solid content in solid content of the said photosensitive soldering resist composition solution of the said epoxy resin or a polyfunctional oxetane compound, According to the objective, it can select suitably, For example, 2-50 % By mass is preferable, and 3 to 30% by mass is more preferable. If the solid content is less than 2% by mass, the hygroscopicity of the cured film is increased, resulting in deterioration of insulation, or solder heat resistance, electroless plating resistance, etc. may be reduced. If it exceeds 50% by mass, the developability may deteriorate and the exposure sensitivity may decrease, which is not preferable.

-Other thermal crosslinking agents-
The other thermal crosslinking agent can be added separately from the epoxy resin and the polyfunctional oxetane compound. The thermal crosslinking agent is not particularly limited and can be appropriately selected depending on the purpose. For example, a polyisocyanate compound described in JP-A-5-9407 can be used. As the polyisocyanate compound, It may be derived from an aliphatic, cycloaliphatic or aromatic group-substituted aliphatic compound containing at least two isocyanate groups.
Specifically, a mixture of 1,3-phenylene diisocyanate and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate, 1,3- and 1,4-xylylene diisocyanate, bis (4 -Isocyanate-phenyl) methane, bis (4-isocyanatocyclohexyl) methane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc .; bifunctional isocyanate; An adduct of the polyfunctional alcohol with an alkylene oxide adduct and the bifunctional isocyanate; hexamethylene diisocyanate, hexamethylene-1,6-diisocyanate Over preparative and cyclic trimer of such derivatives, and the like.

Further, for the purpose of improving the preservability of the photosensitive solder resist composition or the photosensitive solder resist film, a compound obtained by reacting a blocking agent with the isocyanate group of the polyisocyanate and its derivative is used. May be.
The isocyanate group blocking agent is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alcohols such as isopropanol and tert-butanol; lactams such as ε-caprolactam; phenol, cresol, p- phenols such as tert-butylphenol, p-sec-butylphenol, p-sec-amylphenol, p-octylphenol and p-nonylphenol; heterocyclic hydroxyl compounds such as 3-hydroxypyridine and 8-hydroxyquinoline; dialkylmalonate; Active methylene compounds such as methyl ethyl ketoxime, acetylacetone, alkyl acetoacetate oxime, acetoxime, cyclohexanone oxime; and the like. In addition to these, compounds having at least one polymerizable double bond and at least one blocked isocyanate group in the molecule described in JP-A-6-295060 can be used.

  Moreover, an aldehyde condensation product, a resin precursor, etc. can be used. Specifically, N, N′-dimethylolurea, N, N′-dimethylolmalonamide, N, N′-dimethylolsuccinimide, trimethylolmelamine, tetramethylolmelamine, hexamethylolmelamine, 1,3-N, N'-dimethylol terephthalamide, 2,4,6-trimethylolphenol, 2,6-dimethylol-4-methyliloanisole, 1,3-dimethylol-4,6-diisopropylbenzene and the like can be mentioned. Instead of these methylol compounds, the corresponding ethyl or butyl ether, or acetic acid or propionic acid ester may be used. Moreover, you may use the hexamethylated methylol melamine which consists of a formaldehyde condensation product of a melamine and urea, the butyl ether of a melamine and a formaldehyde condensation product, etc.

<Inorganic filler>
The inorganic filler has the functions of improving the surface hardness of the permanent pattern, keeping the coefficient of linear expansion low, and keeping the dielectric constant and dielectric loss tangent of the cured layer itself low.
The inorganic filler is not particularly limited and can be appropriately selected from known ones. For example, kaolin, barium sulfate, barium titanate, silicon oxide powder, finely divided silicon oxide, vapor-phase process silica, none Examples include regular silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica.

The average particle size of the inorganic filler is preferably less than 3 μm, more preferably 0.1 to 2 μm. If the average particle size is 3 μm or more, resolution may be deteriorated due to light scattering.
5-75 mass% is preferable, as for the addition amount of the said inorganic filler, 8-70 mass% is more preferable, and 10-65 mass% is especially preferable. When the addition amount is less than 5% by mass, the coefficient of linear expansion may not be sufficiently reduced. When the addition amount exceeds 90% by mass, when a cured film is formed on the surface of the photosensitive solder resist layer, The film quality of the cured film becomes fragile, and when a wiring is formed using a permanent pattern, the function as a protective film for the wiring may be impaired.

Further, organic fine particles can be added as necessary. Suitable organic fine particles are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include melamine resin, benzoguanamine resin, and crosslinked polystyrene resin. Further, silica having an average particle size of 0.1 to ² μm and an oil absorption of about 100 to 200 m ² / g, spherical porous fine particles made of a crosslinked resin, and the like can be used.

  Since the inorganic filler contains particles having an average particle diameter of 0.1 to 2 μm, even if the permanent pattern is thinned to a thickness of 5 to 20 μm along with the thinning of the printed wiring board, The inorganic filler particles do not cross-link the front and back surfaces of the permanent pattern, and as a result, no ion migration occurs even in the high acceleration test (HAST), and a permanent pattern excellent in heat resistance and moisture resistance can be obtained. .

<Colorant>
There is no restriction | limiting in particular as said coloring agent, According to the objective, it can select suitably, For example, dyes, such as a coloring pigment selected suitably from well-known dyes, can be used.

-Color pigment-
There is no restriction | limiting in particular as said coloring pigment, According to the objective, it can select suitably, For example, Victoria pure blue BO (CI. 42595), auramine (CI. 41000), fat black HB (CI. 26150), Monolite Yellow GT (CI Pigment Yellow 12), Permanent Yellow GR (CI Pigment Yellow 17), Permanent Yellow HR (CI Pigment Yellow HR). Yellow 83), Permanent Carmine FBB (CI Pigment Red 146), Hoster Balm Red ESB (CI Pigment Violet 19), Permanent Ruby FBH (CI Pigment Red 11) Fastel Pink B Supra (CI Pigment Red 81) Monastral Fa Strike Blue (C.I. Pigment Blue 15), mono Light Fast Black B (C.I. Pigment Black 1), carbon, C. I. Pigment red 97, C.I. I. Pigment red 122, C.I. I. Pigment red 149, C.I. I. Pigment red 168, C.I. I. Pigment red 177, C.I. I. Pigment red 180, C.I. I. Pigment red 192, C.I. I. Pigment red 215, C.I. I. Pigment green 7, C.I. I. Pigment green 36, C.I. I. Pigment blue 15: 1, C.I. I. Pigment blue 15: 4, C.I. I. Pigment blue 15: 6, C.I. I. Pigment blue 22, C.I. I. Pigment blue 60, C.I. I. Pigment blue 64 and the like. These may be used alone or in combination of two or more.

  The solid content in the solid content of the photosensitive solder resist composition solution of the color pigment can be determined in consideration of the exposure sensitivity, resolution, etc. of the photosensitive solder resist layer during permanent pattern formation. Although it varies depending on the kind of the color pigment, generally 0.1 to 10% by mass is preferable, and 0.5 to 8% by mass is more preferable.

<Thermosetting accelerator>
The thermosetting accelerator has a function of accelerating the thermosetting of the epoxy resin compound or the polyfunctional oxetane compound, and is preferably added to the photosensitive resin.
The thermosetting accelerator is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy. Amine compounds such as -N, N-dimethylbenzylamine and 4-methyl-N, N-dimethylbenzylamine; quaternary ammonium salt compounds such as triethylbenzylammonium chloride; blocked isocyanate compounds such as dimethylamine; imidazole and 2-methyl Imidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4-methyl Imidazole Any imidazole derivatives bicyclic amidine compounds and salts thereof; phosphorus compounds such as triphenylphosphine; guanamine compounds such as melamine, guanamine, acetoguanamine, benzoguanamine; 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2 -Vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid S-triazine derivatives such as adducts, boron trifluoride-amine complex, organic hydrazide cumulative, phthalic anhydride, trimellitic anhydride, ethylene glycol bis (anhydro trimellitate), glycerol tris (anhydro trimellitate) , Benzo Aromatic acid anhydrides such as phenonetetracarboxylic anhydride, aliphatic acid anhydrides such as maleic anhydride and tetrahydrophthalic anhydride, polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac and alkylphenol novolac Etc. can be used. These may be used alone or in combination of two or more. The epoxy resin compound or the polyfunctional oxetane compound is a curing catalyst, or any compound capable of promoting the reaction of the carboxyl group with these, and any compound capable of promoting thermal curing other than the above. May be used.
The solid content in the solid content of the photosensitive solder resist composition solution of the epoxy resin, the polyfunctional oxetane compound, and a compound capable of accelerating thermal curing between these and the carboxylic acid is usually 0.01 to 20%. % By mass.

<Other ingredients>
The other component is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include solvents, adhesion promoters, thermal polymerization inhibitors, plasticizers, and other additives. Adhesion promoters and other auxiliaries (eg, conductive particles, fillers, antifoaming agents, flame retardants, leveling agents, peeling accelerators, antioxidants, fragrances, surface tension modifiers, chain transfer) Or other agents) may be used in combination. By appropriately containing these components, properties such as stability, photographic properties, film physical properties, etc. of the intended photosensitive solder resist composition or photosensitive solder resist film can be adjusted.

-Solvent-
There is no restriction | limiting in particular as said solvent, According to the objective, it can select suitably, For example, alcohols, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, n-hexanol; acetone , Ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diisobutyl ketone; esters such as ethyl acetate, butyl acetate, n-amyl acetate, methyl sulfate, ethyl propionate, dimethyl phthalate, ethyl benzoate, and methoxypropyl acetate Aromatic hydrocarbons such as toluene, xylene, benzene, ethylbenzene; halogenated carbonization such as carbon tetrachloride, trichloroethylene, chloroform, 1,1,1-trichloroethane, methylene chloride, monochlorobenzene Motorui; tetrahydrofuran, diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethers such as 1-methoxy-2-propanol; dimethylformamide, dimethylacetamide, dimethyl sulfoxide, and sulfolane. These may be used alone or in combination of two or more. Moreover, you may add a well-known surfactant.

-Adhesion promoter-
The adhesion promoter has a function of improving adhesion between layers, adhesion between a photosensitive solder resist layer and a substrate, and electrolytic corrosion.
The adhesion promoter is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include melamine, acetoguanamine, benzoguatemine, melamine-phenol formalin resin, ethyldiamino-S-triazine, 2,4-diamino. And triazine compounds such as -S-triazine and 2,4-diamino-6-xylyl-S-triazine. Commercially available triazine compounds include Shikoku Kasei Kogyo Co., Ltd. shown in the following structural formulas (A) to (C); 2MZ-AZINE (structural formula (A)), 2E4MZ-AZINE (structural formula (B)), CllZ -AZINE (structural formula (C)), and the like.

  These compounds increase the adhesion to the copper circuit, improve the PCT resistance, and have an effect on electrolytic corrosion. These can be used alone or in combination of two or more. 0.1-40 mass% is preferable with respect to photosensitive soldering resist composition solid content, and, as for the compounding quantity of an adhesion promoter, 0.1-20 mass% is more preferable.

-Thermal polymerization inhibitor-
The thermal polymerization inhibitor is preferably added to prevent thermal polymerization or temporal polymerization of the polymerizable compound and improve storage stability.
The thermal polymerization inhibitor is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 4-methoxyphenol, hydroquinone, hydroquinone monomethyl ether, alkyl or aryl-substituted hydroquinone, t-butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, cuprous chloride, phenothiazine, chloranil, naphthylamine, β-naphthol, 2,6-di-t-butyl-4-cresol, 2,2′-methylenebis ( 4-methyl-6-tert-butylphenol), pyridine, nitrobenzene, dinitrobenzene, picric acid, 4-toluidine, methylene blue, copper and organic chelating agent reactant, methyl salicylate, and phenothiazine, nitroso compound, nitroso compound Such as chelates with Al and the like.

  As content of the said thermal-polymerization inhibitor, 0.001-5 mass% is preferable with respect to the said polymeric compound, 0.005-2 mass% is more preferable, 0.01-1 mass% is especially preferable. When the content is less than 0.001% by mass, stability during storage may be lowered, and when it exceeds 5% by mass, sensitivity to active energy rays may be lowered.

-Other additives-
The other additive is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include thixotropic agents such as benton, montmorillonite, aerosol, amide wax, silicone-based, fluorine-based, and polymer-based. Additives such as antifoaming agents and leveling agents can be used.

(Photosensitive solder resist film)
As shown in FIG. 1, the photosensitive solder resist film has at least a support 1 and a photosensitive solder resist layer 2, preferably has a protective film 3, and further, if necessary. , And other layers such as a cushion layer and an oxygen barrier layer (hereinafter abbreviated as a PC layer).
The form of the photosensitive film is not particularly limited and can be appropriately selected according to the purpose. For example, the photosensitive film has the photosensitive solder resist layer and the protective film on the support in this order. A form in which the PC layer, the photosensitive solder resist layer, and the protective film are provided in this order on the support, and the cushion layer, the PC layer, and the photosensitive solder on the support. Examples include a resist layer and a form having the protective film in this order. The photosensitive solder resist layer may be a single layer or a plurality of layers.

-Support-
The support is not particularly limited and may be appropriately selected depending on the purpose. It is preferable that the photosensitive solder resist layer can be peeled off and has good light transmittance. It is more preferable that the smoothness is good.

The support is preferably made of a synthetic resin and transparent, for example, polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, cellulose triacetate, cellulose diacetate, poly (meth) acrylic acid alkyl ester, poly ( (Meth) acrylic acid ester copolymer, polyvinyl chloride, polyvinyl alcohol, polycarbonate, polystyrene, cellophane, polyvinylidene chloride copolymer, polyamide, polyimide, vinyl chloride / vinyl acetate copolymer, polytetrafluoroethylene, polytrifluoro Various plastic films such as ethylene, cellulosic film, nylon film and the like can be mentioned, and among these, polyethylene terephthalate is particularly preferable. These may be used alone or in combination of two or more.
As the support, for example, the support described in JP-A-4-208940, JP-A-5-80503, JP-A-5-173320, JP-A-5-72724, or the like is used. You can also.

There is no restriction | limiting in particular as thickness of the said support body, According to the objective, it can select suitably, For example, 4-300 micrometers is preferable and 5-175 micrometers is more preferable.
There is no restriction | limiting in particular as a shape of the said support body, According to the objective, it can select suitably, A long shape is preferable. There is no restriction | limiting in particular as the length of the said elongate support body, For example, the thing of length 10m-20000m is mentioned.

(Photosensitive solder resist layer)
The photosensitive solder resist layer is formed by the photosensitive solder resist composition of the present invention.
There is no restriction | limiting in particular as a location provided in the said photosensitive soldering resist film of the said photosensitive soldering resist layer, Although it can select suitably according to the objective, Usually, it laminates | stacks on the said support body.
After the photosensitive solder resist layer modulates the light from the light irradiating means by the light modulating means having n picture elements for receiving and emitting the light from the light irradiating means in an exposure step to be described later, It is preferable that the exposure is performed with light passing through a microlens array in which microlenses having aspherical surfaces capable of correcting aberration due to distortion of the exit surface in the picture element portion are arranged.

  There is no restriction | limiting in particular as thickness of the said photosensitive soldering resist layer, According to the objective, it can select suitably, For example, 3-100 micrometers is preferable and 5-70 micrometers is more preferable.

  As the method for forming the photosensitive solder resist layer, the photosensitive solder resist composition is prepared by dissolving, emulsifying or dispersing the photosensitive solder resist composition of the present invention in water or the solvent on the support. A method of laminating by preparing a solution, applying the solution directly, and drying the solution may be mentioned.

The coating method is not particularly limited and can be appropriately selected depending on the purpose. For example, using a spin coater, a slit spin coater, a roll coater, a die coater, a curtain coater, or the like, it is directly applied to the support. The method of apply | coating is mentioned.
The drying conditions vary depending on each component, the type of solvent, the use ratio, and the like, but are usually about 60 to 110 ° C. for about 30 seconds to 15 minutes.

-Protective film-
The protective film has a function of preventing and protecting the photosensitive solder resist layer from being stained and damaged.
There is no restriction | limiting in particular as a location provided in the said photosensitive soldering resist film of the said protective film, Although it can select suitably according to the objective, Usually, it provides on the said photosensitive soldering resist layer.
Examples of the protective film include those used for the support, silicone paper, polyethylene, paper laminated with polypropylene, polyolefin or polytetrafluoroethylene sheet, and among these, polyethylene film, Polypropylene film is preferred.
There is no restriction | limiting in particular as thickness of the said protective film, Although it can select suitably according to the objective, For example, 5-100 micrometers is preferable and 8-30 micrometers is more preferable.

When the protective film is used, the adhesive strength A between the photosensitive solder resist layer and the support and the adhesive strength B between the photosensitive solder resist layer and the protective film satisfy the relationship of adhesive strength A> adhesive strength B. It is preferable.
Examples of the combination of the support and the protective film (support / protective film) include polyethylene terephthalate / polypropylene, polyethylene terephthalate / polyethylene, polyvinyl chloride / cellophane, polyimide / polypropylene, polyethylene terephthalate / polyethylene terephthalate, and the like. . Moreover, the relationship of the above-mentioned adhesive force can be satisfy | filled by surface-treating at least any one of a support body and a protective film. The surface treatment of the support may be performed in order to increase the adhesive force with the photosensitive solder resist layer, for example, coating of a primer layer, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, high frequency irradiation. Treatment, glow discharge irradiation treatment, active plasma irradiation treatment, laser beam irradiation treatment and the like.

Moreover, as a static friction coefficient of the said support body and the said protective film, 0.3-1.4 are preferable and 0.5-1.2 are more preferable.
When the coefficient of static friction is less than 0.3, slipping is excessive, so that winding deviation may occur when the roll is formed. Sometimes.

  The photosensitive solder resist film is preferably wound around a cylindrical core, wound into a long roll, and stored. There is no restriction | limiting in particular as length of the said elongate photosensitive soldering resist film, For example, it can select suitably from the range of 10m-20,000m. Further, slitting may be performed so that the user can easily use, and a long body in the range of 100 m to 1,000 m may be formed into a roll. In this case, it is preferable that the support is wound up so as to be the outermost side. The roll-shaped photosensitive solder resist film may be slit into a sheet shape. When storing, from the viewpoint of protecting the end face and preventing edge fusion, it is preferable to install a separator (particularly moisture-proof and containing a desiccant) on the end face, and use a low moisture-permeable material for packaging. Is preferred.

The protective film may be surface-treated in order to adjust the adhesiveness between the protective film and the photosensitive solder resist layer. In the surface treatment, for example, an undercoat layer made of a polymer such as polyorganosiloxane, fluorinated polyolefin, polyfluoroethylene, or polyvinyl alcohol is formed on the surface of the protective film. The undercoat layer can be formed by applying the polymer coating solution to the surface of the protective film, and then drying at 30 to 150 ° C. (especially 50 to 120 ° C.) for 1 to 30 minutes.
In addition to the photosensitive solder resist layer, the support, and the protective film, a cushion layer, an oxygen blocking layer (PC layer), a release layer, an adhesive layer, a light absorbing layer, a surface protective layer, and the like are provided. May be.
The cushion layer is a layer that has no tackiness at room temperature and melts and flows when laminated under vacuum and heating conditions.
The PC layer is usually a film of about 1.5 μm formed mainly of polyvinyl alcohol.
The photosensitive solder resist film of the present invention has a photosensitive solder resist layer in which a photosensitive solder resist composition having excellent storage stability and excellent chemical resistance, surface hardness, heat resistance and the like after development is laminated. Do it. For this reason, it can be widely used for the formation of permanent patterns such as printed wiring boards, color filters, pillar materials, rib materials, spacers, partition walls, holograms, micromachines, proofs, and the like. It can be suitably used for the forming method.
In particular, since the photosensitive solder resist film of the present invention has a uniform thickness, even when the permanent pattern (protective film, interlayer insulating film, solder resist, etc.) is thinned, In the acceleration test (HAST), ion migration does not occur, and a high-definition permanent pattern excellent in heat resistance and moisture resistance can be obtained, so that the lamination to the substrate is performed more finely.

(Permanent pattern and permanent pattern forming method)
The permanent pattern of the present invention is obtained by the permanent pattern forming method of the present invention.
In the permanent pattern forming method of the present invention, as a first aspect, the photosensitive solder resist composition of the present invention is applied to the surface of a substrate, dried to form a photosensitive solder resist layer, and then exposed. develop.
Further, in the method for forming a permanent pattern of the present invention, as a second aspect, the photosensitive solder resist film of the present invention is laminated on the surface of the substrate under at least one of heating and pressurization, and then exposed. develop.
Hereinafter, the details of the permanent pattern of the present invention will be clarified through the description of the method for forming a permanent pattern of the present invention.

-Base material-
The base material is not particularly limited and can be appropriately selected from known materials having a high surface smoothness to a surface having an uneven surface. A plate-shaped base material (substrate) is preferable, Specifically, a known printed wiring board forming substrate (for example, a copper-clad laminate), a glass plate (for example, a soda glass plate), a synthetic resin film, paper, a metal plate, etc. may be mentioned. Among them, a printed wiring board forming substrate is preferable, and the printed wiring board forming substrate has already been formed with a wiring in that it enables high-density mounting of a semiconductor or the like on a multilayer wiring board or a build-up wiring board. Is particularly preferred.

  The substrate is a laminate in which a photosensitive solder resist layer made of the photosensitive solder resist composition is formed on the substrate as the first aspect, or the photosensitive solder as the second aspect. It can be used by forming a laminate in which the photosensitive solder resist layers in the resist film are laminated so as to overlap. That is, by exposing the photosensitive solder resist layer in the laminated body to be described later, the exposed region can be cured, and a permanent pattern can be formed by developing to be described later.

-Laminate-
There is no restriction | limiting in particular as a formation method of the laminated body of a said 1st aspect, According to the objective, it can select suitably, The said photosensitive soldering resist composition is apply | coated and dried on the said base material. It is preferable to laminate the photosensitive solder resist layer.
The coating and drying method is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the photosensitivity performed when the photosensitive solder resist layer in the photosensitive solder resist film is formed. It can be performed by the same method as the application and drying of the solder resist composition solution. For example, the photosensitive solder resist composition solution is applied using a spin coater, slit spin coater, roll coater, die coater, curtain coater, etc. The method of doing is mentioned.

There is no restriction | limiting in particular as a formation method of the laminated body of the said 2nd aspect, According to the objective, it can select suitably, At least any one of a heating and pressurization of the said photosensitive soldering resist film on the said base material is possible. It is preferable to laminate while carrying out. In addition, when the said photosensitive soldering resist film has the said protective film, it is preferable to peel this protective film and to laminate | stack so that the said photosensitive soldering resist layer may overlap with the said base material.
There is no restriction | limiting in particular as said heating temperature, According to the objective, it can select suitably, For example, 70-130 degreeC is preferable and 80-110 degreeC is more preferable.
There is no restriction | limiting in particular as a pressure of the said pressurization, According to the objective, it can select suitably, For example, 0.01-1.0 MPa is preferable and 0.05-1.0 MPa is more preferable.

  There is no restriction | limiting in particular as an apparatus which performs at least any one of the said heating and pressurization, According to the objective, it can select suitably, For example, heat press, a heat roll laminator (For example, Taisei Laminator company make, VP-II). ), A vacuum laminator (for example, VP130 manufactured by Nichigo Morton Co., Ltd.) and the like.

[Exposure process]
The exposure step is a step of exposing the photosensitive solder resist layer.

  The subject of the exposure is not particularly limited as long as it is a material having a photosensitive solder resist layer, and can be appropriately selected according to the purpose. For example, the photosensitive solder resist composition or the above-mentioned on a substrate It is preferable to carry out with respect to the laminate obtained by forming a photosensitive solder resist film.

  There is no restriction | limiting in particular as exposure to the said laminated body, According to the objective, it can select suitably, For example, even if it exposes the said photosensitive soldering resist layer through the said support body, cushion layer, and PC layer. Well, after peeling off the support, the photosensitive solder resist layer may be exposed through the cushion layer and the PC layer, and after peeling off the support and the cushion layer, the above-mentioned via the PC layer. The photosensitive solder resist layer may be exposed or the photosensitive solder resist layer may be exposed after the support, the cushion layer and the PC layer are peeled off.

  There is no restriction | limiting in particular as said exposure, According to the objective, it can select suitably, Digital exposure, analog exposure, etc. are mentioned, Among these, digital exposure is preferable.

  The digital exposure is not particularly limited and can be appropriately selected depending on the purpose. For example, a control signal is generated based on pattern formation information to be formed, and light modulated in accordance with the control signal is used. Preferably.

  The digital exposure means is not particularly limited and may be appropriately selected depending on the purpose. For example, light irradiation means for irradiating light, light emitted from the light irradiation means based on pattern information to be formed And a light modulation means for modulating the light intensity.

<Light modulation means>
The light modulation means is not particularly limited as long as it can modulate light, and can be appropriately selected according to the purpose. For example, it preferably has n pixel portions.
There is no restriction | limiting in particular as a light modulation means which has the said n image drawing part, According to the objective, it can select suitably, For example, a spatial light modulation element is preferable.

  Examples of the spatial light modulator include a digital micromirror device (DMD), a MEMS (Micro Electro Mechanical Systems) type spatial light modulator (SLM), and modulates transmitted light by an electro-optic effect. An optical element (PLZT element), a liquid crystal optical shutter (FLC), etc. are mentioned, Among these, DMD is mentioned suitably.

The light modulation means preferably includes pattern signal generation means for generating a control signal based on pattern information to be formed. In this case, the light modulation unit modulates light according to the control signal generated by the pattern signal generation unit.
There is no restriction | limiting in particular as said control signal, According to the objective, it can select suitably, For example, a digital signal is mentioned suitably.

Hereinafter, an example of the light modulation means will be described with reference to the drawings.
As shown in FIG. 2, the DMD 50 has a large number (eg, 1,024 × 768) of micromirrors (micromirrors) 62 each constituting a pixel (pixel) on a SRAM cell (memory cell) 60. It is a mirror device arranged in a shape. In each pixel, a micromirror 62 supported by a support column is provided at the top, and a material having high reflectance such as aluminum is deposited on the surface of the micromirror 62. In addition, the reflectance of the micromirror 62 is 90% or more, and the arrangement pitch is 13.7 μm as an example in both the vertical direction and the horizontal direction. A silicon gate CMOS SRAM cell 60 manufactured in a normal semiconductor memory manufacturing line is disposed directly below the micromirror 62 via a support including a hinge and a yoke. The entire structure is monolithic. ing.

  When a digital signal is written in the SRAM cell 60 of the DMD 50, the micromirror 62 supported by the support is tilted in a range of ± α degrees (for example, ± 12 degrees) with respect to the substrate side on which the DMD 50 is disposed with the diagonal line as the center. It is done. 3A shows a state in which the micromirror 62 is tilted to + α degrees when the micromirror 62 is in an on state, and FIG. 3B shows a state in which the micromirror 62 is tilted to −α degrees that is in an off state. Therefore, by controlling the tilt of the micromirror 62 in each pixel of the DMD 50 according to the pattern information as shown in FIG. 2, the laser light B incident on the DMD 50 is reflected in the tilt direction of each micromirror 62. The

  FIG. 2 shows an example of a state in which a part of the DMD 50 is enlarged and the micromirror 62 is controlled to + α degrees or −α degrees. The on / off control of each micromirror 62 is performed by the controller 302 (see FIG. 13) connected to the DMD 50. Further, a light absorber (not shown) is arranged in the direction in which the laser beam B reflected by the off-state micromirror 62 travels.

  Further, it is preferable that the DMD 50 is arranged with a slight inclination so that the short side forms a predetermined angle θ (for example, 0.1 ° to 5 °) with the sub-scanning direction. 4A shows the scanning trajectory of the reflected light image (exposure beam) 53 by each micromirror when the DMD 50 is not tilted, and FIG. 4B shows the scanning trajectory of the exposure beam 53 when the DMD 50 is tilted. Show.

In the DMD 50, a number of micromirror arrays in which a large number (for example, 1,024) of micromirrors are arranged in the longitudinal direction are arranged in a short direction (for example, 756 sets). as shown in), by inclining the DMD 50, the pitch P ₂ of the scanning locus of the exposure beams 53 from each micromirror (scan line), it becomes narrower than the pitch P ₁ of the scanning line in the case of not tilting the DMD 50, the resolution Can be greatly improved. On the other hand, the inclination angle of the DMD 50 is small, the scanning width _{W 2} in the case of tilting the DMD 50, which is substantially equal to the scanning width _{W 1} when not inclined DMD 50.

Next, a method for increasing the modulation speed in the optical modulation means (hereinafter referred to as “high-speed modulation”) will be described.
It is preferable that the light modulation unit can control any less than n number of pixel parts arranged continuously from the n number of picture elements according to pattern information. There is a limit to the data processing speed of the light modulation means, and the modulation speed per line is determined in proportion to the number of pixels to be used. By using, the modulation speed per line is increased.

Hereinafter, the high-speed modulation will be further described with reference to the drawings.
When the DMD 50 is irradiated with the laser beam B from the fiber array light source 66, the laser beam reflected when the micromirror of the DMD 50 is in the on state is imaged on the photosensitive solder resist layer 150 by the lens systems 54 and 58. The In this manner, the laser light emitted from the fiber array light source 66 is turned on / off for each pixel, and the photosensitive solder resist layer 150 is exposed in the same number of pixel units (exposure area 168) as the number of pixels used in the DMD 50. Is done. Further, the photosensitive solder resist layer 150 is moved at a constant speed together with the stage 152, whereby the photosensitive solder resist layer 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162, and a strip-like pattern is formed for each exposure head 166. An exposed area 170 is formed.

  In this example, as shown in FIGS. 5A and 5B, in the DMD 50, 768 sets of micromirror arrays in which 1024 micromirrors are arranged in the main scanning direction are arranged in the subscanning direction. In this example, the controller 302 (see FIG. 13) controls so that only a part of the micromirror rows (for example, 1024 × 256 rows) are driven.

  In this case, a micromirror array arranged at the center of the DMD 50 as shown in FIG. 5 (A) may be used, and a micromirror arranged at the end of the DMD 50 as shown in FIG. 5 (B). A column may be used. In addition, when a defect occurs in some of the micromirrors, the micromirror array to be used may be appropriately changed depending on the situation, such as using a micromirror array in which no defect has occurred.

  Since the data processing speed of the DMD 50 is limited and the modulation speed per line is determined in proportion to the number of pixels used, the modulation speed per line can be increased by using only a part of the micromirror array. Get faster. On the other hand, in the case of an exposure method in which the exposure head is continuously moved relative to the exposure surface, it is not necessary to use all the pixels in the sub-scanning direction.

  When the sub-scan of the photosensitive solder resist layer 150 by the scanner 162 is finished and the rear end of the photosensitive solder resist layer 150 is detected by the sensor 164, the stage 152 is gated along the guide 158 by the stage driving device 304. It returns to the origin on the most upstream side of 160 and is moved again along the guide 158 from the upstream side to the downstream side of the gate 160 at a constant speed.

  For example, in the case of using only 384 sets out of 768 sets of micromirror arrays, the modulation can be performed twice as fast per line as compared with the case of using all 768 sets. Also, when only 256 pairs are used in the 768 sets of micromirror arrays, modulation can be performed three times faster per line than when all 768 sets are used.

  As described above, according to the pattern forming method of the present invention, the micromirror array in which 1,024 micromirrors are arranged in the main scanning direction includes the DMD in which 768 sets are arranged in the subscanning direction. By controlling so that only a part of the micromirror rows are driven by the controller, the modulation rate per line becomes faster than when all the micromirror rows are driven.

  In addition, an example in which the DMD micromirror is partially driven has been described, but the length of the direction corresponding to the predetermined direction is reflected on the substrate longer than the length of the direction intersecting the predetermined direction according to the control signal. Even if a long and narrow DMD in which a large number of micromirrors capable of changing the surface angle are arranged in a two-dimensional manner is used, the number of micromirrors for controlling the angle of the reflecting surface is reduced. Can do.

  The exposure method is preferably performed while relatively moving the exposure light and the photosensitive solder resist layer. In this case, it is preferable to use the high-speed modulation together. Thereby, high-speed exposure can be performed in a short time.

  In addition, as shown in FIG. 6, the entire surface of the photosensitive solder resist layer 150 may be exposed by a single scan in the X direction by the scanner 162, and as shown in FIGS. 7A and 7B, After scanning the photosensitive solder resist layer 150 in the X direction by the scanner 162, the scanner 162 is moved one step in the Y direction, and scanning is performed in the X direction. The entire surface of the photosensitive solder resist layer 150 may be exposed. In this example, the scanner 162 includes 18 exposure heads 166. Note that the exposure head includes at least the light irradiation unit and the light modulation unit.

  The exposure is performed on a partial area of the photosensitive solder resist layer so that the partial area is cured, and an uncured area other than the cured partial area in a development process described later. Are removed to form a permanent pattern.

Next, an example of a pattern forming apparatus including the light modulation means will be described with reference to the drawings.
As shown in FIG. 8, the pattern forming apparatus including the light modulation means includes a flat stage 152 that holds the laminated body having the photosensitive solder resist layer 150 by adsorbing to the surface.
Two guides 158 extending along the stage moving direction are installed on the upper surface of the thick plate-like installation table 156 supported by the four legs 154. The stage 152 is arranged so that the longitudinal direction thereof faces the stage moving direction, and is supported by a guide 158 so as to be reciprocally movable. The pattern forming apparatus has a drive device (not shown) for driving the stage 152 along the guide 158.

  A U-shaped gate 160 is provided at the center of the installation table 156 so as to straddle the movement path of the stage 152. Each of the ends of the U-shaped gate 160 is fixed to both side surfaces of the installation table 156. A scanner 162 is provided on one side of the gate 160, and a plurality of (for example, two) detection sensors 164 for detecting the front and rear ends of the photosensitive solder resist layer 150 are provided on the other side. ing. The scanner 162 and the detection sensor 164 are respectively attached to the gate 160 and fixedly arranged above the moving path of the stage 152. The scanner 162 and the detection sensor 164 are connected to a controller (not shown) that controls them.

As shown in FIGS. 9 and 10B, the scanner 162 includes a plurality of (for example, 14) exposure heads 166 arranged in an approximately matrix of m rows and n columns (for example, 3 rows and 5 columns). ing. In this example, four exposure heads 166 are arranged in the third row in relation to the width of the photosensitive solder resist layer 150. In addition, when showing each exposure head arranged in the m-th row and the n-th column, it is expressed as an exposure head 166 _mn .

An exposure area 168 by the exposure head 166 has a rectangular shape with a short side in the sub-scanning direction. Therefore, as the stage 152 moves, a strip-shaped exposed region 170 is formed in the photosensitive solder resist layer 150 for each exposure head 166. In addition, when showing the exposure area by each exposure head arranged in the m-th row and the n-th column, it is expressed as an exposure area 168 _mn .

Further, as shown in FIGS. 10A and 10B, each of the exposure heads in each row arranged in a line so that the strip-shaped exposed regions 170 are arranged without gaps in the direction orthogonal to the sub-scanning direction. These are arranged with a predetermined interval (natural number times the long side of the exposure area, twice in this example) in the arrangement direction. Therefore, can not be exposed portion between the exposure area _{168 11} in the first row and the exposure area _{168 12,} it can be exposed by the second row of the exposure area _{168 21} and the exposure area _{168 31} in the third row.

As shown in FIGS. 11 and 12, each of the exposure heads 166 _{11 to} 166 _mn serves as the light modulation means (spatial light modulation element that modulates each pixel) according to pattern information. A digital micromirror device (DMD) 50 manufactured by Texas Instruments, USA is provided. The DMD 50 is connected to the controller 302 (see FIG. 13) having a data processing unit and a mirror drive control unit. The data processing unit of the controller 302 generates a control signal for driving and controlling each micromirror in the region to be controlled by the DMD 50 for each exposure head 166 based on the input pattern information. The area to be controlled will be described later. The mirror drive control unit controls the angle of the reflection surface of each micromirror of the DMD 50 for each exposure head 166 based on the control signal generated by the pattern information processing unit. The control of the angle of the reflecting surface will be described later.

  On the light incident side of the DMD 50, a fiber array light source 66 including a laser emitting section in which emission ends (light emitting points) of an optical fiber are arranged in a line along a direction corresponding to the long side direction of the exposure area 168, a fiber A lens system 67 for correcting the laser light emitted from the array light source 66 and condensing it on the DMD, and a mirror 69 for reflecting the laser light transmitted through the lens system 67 toward the DMD 50 are arranged in this order. In FIG. 11, the lens system 67 is schematically shown.

  As shown in detail in FIG. 12, the lens system 67 is inserted into the optical path of the light passing through the condenser lens 71 and the condenser lens 71 that collects the laser light B as the illumination light emitted from the fiber array light source 66. A rod-shaped optical integrator (hereinafter referred to as a rod integrator) 72 and an imaging lens 74 disposed in front of the rod integrator 72, that is, on the mirror 69 side. The condensing lens 71, the rod integrator 72, and the imaging lens 74 cause the laser light emitted from the fiber array light source 66 to enter the DMD 50 as a light beam that is close to parallel light and has a uniform beam cross-sectional intensity. The shape and action of the rod integrator 72 will be described in detail later.

  The laser beam B emitted from the lens system 67 is reflected by the mirror 69 and irradiated to the DMD 50 via the TIR (total reflection) prism 70. In FIG. 11, the TIR prism 70 is omitted.

  Further, on the light reflection side of the DMD 50, an imaging optical system 51 that images the laser beam B reflected by the DMD 50 on the photosensitive solder resist layer 150 is disposed. The imaging optical system 51 is schematically shown in FIG. 11, but as shown in detail in FIG. 12, the imaging optical system 51 includes a first imaging optical system including lens systems 52 and 54 and lens systems 57 and 58. A second imaging optical system, a microlens array 55 inserted between these imaging optical systems, and an aperture array 59 are included.

The microlens array 55 is formed by two-dimensionally arranging a large number of microlenses 55a corresponding to the pixels of the DMD 50. In this example, as will be described later, only 1,024 × 256 rows of the 1,024 × 768 rows of micromirrors of the DMD 50 are driven, and accordingly, the microlens 55a has 1,024 × 256 correspondingly. Arranged in columns. The arrangement pitch of the micro lenses 55a is 41 μm in both the vertical and horizontal directions. As an example, the microlens 55a has a focal length of 0.19 mm, an NA (numerical aperture) of 0.11, and is formed from the optical glass BK7. The shape of the micro lens 55a will be described in detail later.
The beam diameter of the laser beam B at the position of each microlens 55a is 41 μm.

  The aperture array 59 is formed by forming a large number of apertures (openings) 59 a corresponding to the respective micro lenses 55 a of the micro lens array 55. The diameter of the aperture 59a is, for example, 10 μm.

  The first imaging optical system forms an image on the microlens array 55 by enlarging the image by the DMD 50 three times. The second imaging optical system enlarges the image passing through the microlens array 55 by 1.6 times, and forms and projects the image on the photosensitive solder resist layer 150. Therefore, as a whole, the image by the DMD 50 is magnified by 4.8 times and is imaged and projected on the photosensitive solder resist layer 150.

  A prism pair 73 is disposed between the second imaging optical system and the photosensitive solder resist layer 150. By moving the prism pair 73 in the vertical direction in FIG. 12, a photosensitive solder resist layer is formed. The focus of the image on 150 can be adjusted. In the figure, the photosensitive solder resist layer 150 is sub-scanned in the direction of arrow F.

The picture element portion is not particularly limited as long as it can receive and emit light from the light irradiation means, and can be appropriately selected according to the purpose. For example, by the permanent pattern forming method of the present invention When the formed permanent pattern is an image pattern, it is a pixel, and when the light modulation means includes a DMD, it is a micromirror.
There is no restriction | limiting in particular as the number (the said n) of picture element parts which the said light modulation element has, It can select suitably according to the objective.
The arrangement of the picture element portions in the light modulation element is not particularly limited and may be appropriately selected depending on the purpose. Is more preferable.

<Light irradiation means>
The light irradiation means is not particularly limited and may be appropriately selected depending on the purpose. For example, (ultra) high pressure mercury lamp, xenon lamp, carbon arc lamp, halogen lamp, copier, fluorescent tube, LED, etc. , A known light source such as a semiconductor laser, or means capable of synthesizing and irradiating two or more lights. Among these, means capable of synthesizing and irradiating two or more lights are preferable.
The light emitted from the light irradiation means is, for example, an electromagnetic wave that passes through the support and activates the photopolymerization initiator and sensitizer used when the light is irradiated through the support. In particular, ultraviolet to visible light, electron beam, X-ray, laser beam, and the like can be mentioned. Of these, laser beam is preferable, and laser beam obtained by combining two or more beams (hereinafter, referred to as “combined laser beam”). ) Is more preferable. Even when light irradiation is performed after the support is peeled off, the same light can be used.

The wavelength of ultraviolet to visible light is preferably, for example, 300 to 1,500 nm, more preferably 320 to 800 nm, and particularly preferably 330 to 650 nm.
As a wavelength of the said laser beam, 200-1500 nm is preferable, for example, 300-800 nm is more preferable, 330-500 nm is still more preferable, 395-415 nm is especially preferable.

  Examples of means capable of irradiating the combined laser beam include a plurality of lasers, a multimode optical fiber, and a set for condensing and coupling the laser beams respectively emitted from the plurality of lasers to the multimode optical fiber. Means having an optical system are preferred.

  Hereinafter, means (fiber array light source) capable of irradiating the combined laser beam will be described with reference to the drawings.

  As shown in FIG. 28 a, the fiber array light source 66 includes a plurality of (for example, 14) laser modules 64, and one end of the multimode optical fiber 30 is coupled to each laser module 64. An optical fiber 31 having the same core diameter as that of the multimode optical fiber 30 and a smaller cladding diameter than the multimode optical fiber 30 is coupled to the other end of the multimode optical fiber 30. As shown in detail in FIG. 28b, seven end portions of the multimode optical fiber 31 opposite to the optical fiber 30 are arranged along the main scanning direction orthogonal to the sub-scanning direction, and are arranged in two rows to form a laser. An emission unit 68 is configured.

  As shown in FIG. 28b, the laser emitting portion 68 configured by the end portion of the multimode optical fiber 31 is sandwiched and fixed between two support plates 65 having a flat surface. Further, a transparent protective plate such as glass is preferably disposed on the light emitting end face of the multimode optical fiber 31 for protection. The light exit end face of the multimode optical fiber 31 has high light density and is likely to collect dust and easily deteriorate. However, the protective plate as described above prevents the dust from adhering to the end face and deteriorates. Can be delayed.

  In this example, in order to arrange the emission ends of the optical fibers 31 having a small cladding diameter in a line without any gap, the multi-mode optical fiber 30 is disposed between two adjacent multi-mode optical fibers 30 in a portion having a large cladding diameter. Two exit ends of the optical fiber 31 coupled to two adjacent multi-mode optical fibers 30 where the exit ends of the optical fibers 31 coupled to the stacked multi-mode optical fibers 30 are adjacent to each other at a portion where the cladding diameter is large. Are arranged so as to be sandwiched between them.

  For example, as shown in FIG. 29, such an optical fiber is coaxial with an optical fiber 31 having a length of 1 to 30 cm and a small cladding diameter at the tip of the laser beam emission side of a multimode optical fiber 30 having a large cladding diameter. Can be obtained by linking them together. In the two optical fibers, the incident end face of the optical fiber 31 is fused and joined to the outgoing end face of the multimode optical fiber 30 so that the central axes of both optical fibers coincide. As described above, the diameter of the core 31 a of the optical fiber 31 is the same as the diameter of the core 30 a of the multimode optical fiber 30.

  Also, a short optical fiber in which an optical fiber having a short length and a large cladding diameter is fused to an optical fiber having a small cladding diameter may be coupled to the output end of the multimode optical fiber 30 via a ferrule or an optical connector. Good. By detachably coupling using a connector or the like, the tip portion can be easily replaced when an optical fiber having a small cladding diameter is broken, and the cost required for exposure head maintenance can be reduced. Hereinafter, the optical fiber 31 may be referred to as an emission end portion of the multimode optical fiber 30.

  The multimode optical fiber 30 and the optical fiber 31 may be any of a step index type optical fiber, a graded index type optical fiber, and a composite type optical fiber. For example, a step index type optical fiber manufactured by Mitsubishi Cable Industries, Ltd. can be used. In the present embodiment, the multimode optical fiber 30 and the optical fiber 31 are step index type optical fibers, and the multimode optical fiber 30 has a cladding diameter = 125 μm, a core diameter = 50 μm, NA = 0.2, an incident end face. The transmittance of the coat is 99.5% or more, and the optical fiber 31 has a cladding diameter = 60 μm, a core diameter = 50 μm, and NA = 0.2.

  In general, in the laser light in the infrared region, the propagation loss increases as the cladding diameter of the optical fiber is reduced. For this reason, a suitable cladding diameter is determined according to the wavelength band of the laser beam. However, the shorter the wavelength, the smaller the propagation loss. In the case of laser light having a wavelength of 405 nm emitted from a GaN-based semiconductor laser, the cladding thickness {(cladding diameter−core diameter) / 2} is set to an infrared light having a wavelength band of 800 nm. The propagation loss hardly increases even if it is about ½ of the case of propagating infrared light and about ¼ of the case of propagating infrared light in the 1.5 μm wavelength band for communication. Therefore, the cladding diameter can be reduced to 60 μm.

  However, the cladding diameter of the optical fiber 31 is not limited to 60 μm. The clad diameter of the optical fiber used in the conventional fiber array light source is 125 μm, but the depth of focus becomes deeper as the clad diameter becomes smaller. Therefore, the clad diameter of the multimode optical fiber is preferably 80 μm or less, preferably 60 μm or less. More preferably, it is 40 μm or less. On the other hand, since the core diameter needs to be at least 3 to 4 μm, the cladding diameter of the optical fiber 31 is preferably 10 μm or more.

  The laser module 64 includes a combined laser light source (fiber array light source) shown in FIG. This combined laser light source includes a plurality of (for example, seven) chip-like lateral multimode or single mode GaN-based semiconductor lasers LD1, LD2, LD3, LD4, LD5, LD6, arrayed and fixed on the heat block 10. And LD7, collimator lenses 11, 12, 13, 14, 15, 16, and 17 provided corresponding to each of the GaN-based semiconductor lasers LD1 to LD7, one condenser lens 20, and one multi-lens. Mode optical fiber 30. The number of semiconductor lasers is not limited to seven. For example, as many as 20 semiconductor laser beams can be incident on a multimode optical fiber having a cladding diameter = 60 μm, a core diameter = 50 μm, and NA = 0.2. In addition, the number of optical fibers can be further reduced.

  The GaN-based semiconductor lasers LD1 to LD7 all have the same oscillation wavelength (for example, 405 nm), and the maximum output is also all the same (for example, 100 mW for the multimode laser and 30 mW for the single mode laser). As the GaN-based semiconductor lasers LD1 to LD7, lasers having an oscillation wavelength other than the above 405 nm in a wavelength range of 350 nm to 450 nm may be used.

  As shown in FIGS. 31 and 32, the combined laser light source is housed in a box-shaped package 40 having an upper opening together with other optical elements. The package 40 includes a package lid 41 created so as to close the opening thereof. After the deaeration process, a sealing gas is introduced, and the package 40 and the package lid 41 are closed by closing the opening of the package 40 with the package lid 41. 41. The combined laser light source is hermetically sealed in a closed space (sealed space) formed by 41.

  A base plate 42 is fixed to the bottom surface of the package 40, and the heat block 10, a condensing lens holder 45 that holds the condensing lens 20, and the multimode optical fiber 30 are disposed on the top surface of the base plate 42. A fiber holder 46 that holds the incident end is attached. The exit end of the multimode optical fiber 30 is drawn out of the package through an opening formed in the wall surface of the package 40.

  Further, a collimator lens holder 44 is attached to the side surface of the heat block 10, and the collimator lenses 11 to 17 are held. An opening is formed in the lateral wall surface of the package 40, and wiring 47 for supplying a driving current to the GaN-based semiconductor lasers LD1 to LD7 is drawn out of the package through the opening.

  In FIG. 32, in order to avoid complication of the figure, only the GaN semiconductor laser LD7 among the plurality of GaN semiconductor lasers is numbered, and only the collimator lens 17 among the plurality of collimator lenses is numbered. is doing.

  FIG. 33 shows the front shape of the attachment part of the collimator lenses 11-17. Each of the collimator lenses 11 to 17 is formed in a shape obtained by cutting a region including the optical axis of a circular lens having an aspherical surface into a long and narrow plane. This elongated collimator lens can be formed, for example, by molding resin or optical glass. The collimator lenses 11 to 17 are closely arranged in the light emitting point arrangement direction so that the length direction is orthogonal to the light emitting point arrangement direction of the GaN-based semiconductor lasers LD1 to LD7 (the horizontal direction in FIG. 33).

  On the other hand, each of the GaN-based semiconductor lasers LD1 to LD7 includes an active layer having a light emission width of 2 μm, and each of the laser beams B1 in a state in which the divergence angles in the direction parallel to and perpendicular to the active layer are 10 ° and 30 °, respectively. A laser emitting ~ B7 is used. These GaN-based semiconductor lasers LD1 to LD7 are arranged so that the light emitting points are arranged in a line in a direction parallel to the active layer.

Therefore, in the laser beams B1 to B7 emitted from the respective light emitting points, the direction in which the divergence angle is large coincides with the length direction and the divergence angle is small with respect to the elongated collimator lenses 11 to 17 as described above. Incident light is incident in a state where the direction coincides with the width direction (direction perpendicular to the length direction). That is, the collimator lenses 11 to 17 have a width of 1.1 mm and a length of 4.6 mm, and the horizontal and vertical beam diameters of the laser beams B1 to B7 incident thereon are 0.9 mm and 2. 6 mm. In addition, each of the collimator lenses 11 to 17 has a focal length f ₁ = 3 mm, NA = 0.6, and a lens arrangement pitch = 1.25 mm.

The condensing lens 20 is obtained by cutting an area including the optical axis of a circular lens having an aspheric surface into a long and narrow shape in parallel planes, and is long in the arrangement direction of the collimator lenses 11 to 17, that is, in the horizontal direction and short in the direction perpendicular thereto. Is formed. This condenser lens 20 has a focal length f ₂ = 23 mm and NA = 0.2. This condensing lens 20 is also formed by molding resin or optical glass, for example.

  In addition, since the light emitting means for illuminating the DMD uses a high-intensity fiber array light source in which the output ends of the optical fibers of the combined laser light source are arranged in an array, it has a high output and a deep depth of focus. A pattern forming apparatus can be realized. Furthermore, since the output of each fiber array light source is increased, the number of fiber array light sources required to obtain a desired output is reduced, and the cost of the pattern forming apparatus can be reduced.

  In addition, since the cladding diameter at the exit end of the optical fiber is smaller than the cladding diameter at the entrance end, the diameter of the light emitting portion is further reduced, and the brightness of the fiber array light source can be increased. Thereby, a pattern forming apparatus having a deeper depth of focus can be realized. For example, even in the case of ultra-high resolution exposure with a beam diameter of 1 μm or less and a resolution of 0.1 μm or less, a deep depth of focus can be obtained, and high-speed and high-definition exposure is possible. Therefore, it is suitable for a thin film transistor (TFT) exposure process that requires high resolution.

  The light irradiating means is not limited to a fiber array light source including a plurality of the combined laser light sources, and for example, emits laser light incident from a single semiconductor laser having one light emitting point. A fiber array light source in which fiber light sources including optical fibers are arrayed can be used.

  Further, as a light irradiation means having a plurality of light emitting points, for example, as shown in FIG. 34, a laser in which a plurality of (for example, seven) chip-shaped semiconductor lasers LD1 to LD7 are arranged on the heat block 100. An array can be used. Further, a chip-shaped multicavity laser 110 in which a plurality of (for example, five) light emitting points 110a shown in FIG. 35A is arranged in a predetermined direction is known. Since the multicavity laser 110 can arrange the light emitting points with high positional accuracy as compared with the case where the chip-shaped semiconductor lasers are arranged, it is easy to multiplex the laser beams emitted from the respective light emitting points. However, as the number of light emitting points increases, the multicavity laser 110 is likely to be bent at the time of laser manufacturing. Therefore, the number of light emitting points 110a is preferably 5 or less.

  As the light irradiation means, the multi-cavity laser 110 or a plurality of multi-cavity lasers 110 on the heat block 100 as shown in FIG. 35 (B) has the same direction as the arrangement direction of the light emitting points 110a of each chip. A multi-cavity laser array arranged in the above can be used as a laser light source.

  The combined laser light source is not limited to one that combines laser beams emitted from a plurality of chip-shaped semiconductor lasers. For example, as shown in FIG. 22, a combined laser light source including a chip-shaped multicavity laser 110 having a plurality of (for example, three) light emitting points 110a can be used. The combined laser light source includes a multi-cavity laser 110, a single multi-mode optical fiber 130, and a condenser lens 120. The multi-cavity laser 110 can be composed of, for example, a GaN-based laser diode having an oscillation wavelength of 405 nm.

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110 a of the multicavity laser 110 is collected by the condenser lens 120 and enters the core 130 a of the multimode optical fiber 130. The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

  A plurality of light emitting points 110 a of the multicavity laser 110 are arranged in parallel within a width substantially equal to the core diameter of the multimode optical fiber 130, and as the condenser lens 120, substantially the same as the core diameter of the multimode optical fiber 130. By using a convex lens having a new focal length and a rod lens that collimates the emitted beam from the multi-cavity laser 110 only in a plane perpendicular to the active layer, the coupling efficiency of the laser beam B to the multimode optical fiber 130 is increased. be able to.

  As shown in FIG. 36, a multi-cavity laser 110 having a plurality of (for example, three) emission points is used, and a plurality of (for example, nine) multi-cavity lasers 110 are equally spaced from each other on the heat block 111. A combined laser light source including the laser array 140 arranged in (1) can be used. The plurality of multi-cavity lasers 110 are arranged and fixed in the same direction as the arrangement direction of the light emitting points 110a of each chip.

  This combined laser light source includes a laser array 140, a plurality of lens arrays 114 arranged corresponding to each multi-capability laser 110, and a single lens arranged between the laser array 140 and the plurality of lens arrays 114. A rod lens 113, one multimode optical fiber 130, and a condenser lens 120 are provided. The lens array 114 includes a plurality of microlenses corresponding to the emission points of the multi-capability laser 110.

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110a of the plurality of multi-cavity lasers 110 is condensed in a predetermined direction by the rod lens 113 and then each microlens of the lens array 114. Is collimated. The collimated laser beam L is condensed by the condensing lens 120 and is incident on the core 130a of the multimode optical fiber 130. The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

  Still another example of the combined laser light source will be described. In this combined laser light source, as shown in FIGS. 37A and 37B, a heat block 182 having an L-shaped cross section in the optical axis direction is mounted on a substantially rectangular heat block 180, and two heats are provided. A storage space is formed between the blocks. On the upper surface of the L-shaped heat block 182, a plurality of (for example, two) multi-cavity lasers 110 in which a plurality of light emitting points (for example, five) are arranged in an array form the light emitting points 110a of each chip. It is arranged and fixed at equal intervals in the same direction as the arrangement direction.

  A concave portion is formed in the substantially rectangular heat block 180, and a plurality of (for example, two) light emitting points (for example, five) are arranged in an array on the upper surface of the space side of the heat block 180. The multi-cavity laser 110 is arranged such that its emission point is located on the same vertical plane as the emission point of the laser chip arranged on the upper surface of the heat block 182.

  On the laser beam emission side of the multi-cavity laser 110, a collimator lens array 184 in which collimator lenses are arranged corresponding to the light emission points 110a of the respective chips is arranged. In the collimating lens array 184, the length direction of each collimating lens coincides with the direction in which the laser beam divergence angle is large (fast axis direction), and the width direction of each collimating lens is in the direction in which the divergence angle is small (slow axis direction). They are arranged to match. Thus, by collimating and integrating the collimating lenses, the space utilization efficiency of the laser light can be improved, the output of the combined laser light source can be increased, and the number of parts can be reduced and the cost can be reduced. .

  Further, on the laser light emitting side of the collimating lens array 184, there is one multimode optical fiber 130 and a condensing lens 120 that condenses and couples the laser light to the incident end of the multimode optical fiber 130. Has been placed.

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110a of the plurality of multi-cavity lasers 110 disposed on the laser blocks 180 and 182 is collimated by the collimating lens array 184 and collected. The light is condensed by the optical lens 120 and enters the core 130 a of the multimode optical fiber 130. The laser light incident on the core 130a propagates in the optical fiber, is combined into one, and is emitted.

  As described above, the combined laser light source can achieve particularly high output by the multistage arrangement of multicavity lasers and the array of collimating lenses. By using this combined laser light source, a higher-intensity fiber array light source or bundle fiber light source can be formed, which is particularly suitable as a fiber light source constituting the laser light source of the pattern forming apparatus.

  It should be noted that a laser module in which each of the combined laser light sources is housed in a casing and the emission end of the multimode optical fiber 130 is pulled out from the casing can be configured.

  In addition, the other end of the multimode optical fiber of the combined laser light source is coupled with another optical fiber having the same core diameter as the multimode optical fiber and a cladding diameter smaller than the multimode optical fiber. However, for example, a multimode optical fiber having a cladding diameter of 125 μm, 80 μm, 60 μm, or the like may be used without coupling another optical fiber to the emission end.

Here, the permanent pattern forming method of the present invention will be further described.
In each exposure head 166 of the scanner 162, laser light B1, B2, B3, B4, B5, B6 emitted in a divergent light state from each of the GaN-based semiconductor lasers LD1 to LD7 constituting the combined laser light source of the fiber array light source 66. , And B7 are collimated by corresponding collimator lenses 11-17. The collimated laser beams B <b> 1 to B <b> 7 are collected by the condenser lens 20 and converge on the incident end face of the core 30 a of the multimode optical fiber 30.

  In this example, the collimator lenses 11 to 17 and the condenser lens 20 constitute a condensing optical system, and the condensing optical system and the multimode optical fiber 30 constitute a multiplexing optical system. That is, the laser beams B1 to B7 collected as described above by the condenser lens 20 enter the core 30a of the multimode optical fiber 30 and propagate through the optical fiber to be combined with one laser beam B. The light is emitted from the optical fiber 31 coupled to the output end of the multimode optical fiber 30.

  In each laser module, when the coupling efficiency of the laser beams B1 to B7 to the multimode optical fiber 30 is 0.85 and each output of the GaN-based semiconductor lasers LD1 to LD7 is 30 mW, the light arranged in an array For each of the fibers 31, a combined laser beam B with an output of 180 mW (= 30 mW × 0.85 × 7) can be obtained. Therefore, the output from the laser emitting unit 68 in which the six optical fibers 31 are arranged in an array is about 1 W (= 180 mW × 6).

  In the laser emitting portion 68 of the fiber array light source 66, light emission points with high luminance are arranged in a line along the main scanning direction as described above. A conventional fiber light source that couples laser light from a single semiconductor laser to a single optical fiber has a low output, so that a desired output cannot be obtained unless multiple rows are arranged. Since the laser light source has a high output, a desired output can be obtained even with a small number of columns, for example, one column.

For example, in a conventional fiber light source in which a semiconductor laser and an optical fiber are coupled on a one-to-one basis, a laser having an output of about 30 mW (milliwatt) is usually used as the semiconductor laser, and the core diameter is 50 μm and the cladding diameter is 125 μm. Since a multimode optical fiber having a numerical aperture (NA) of 0.2 is used, if an output of about 1 W (watt) is to be obtained, 48 multimode optical fibers (8 × 6) must be bundled. Narazu, the area of the light emitting region 0.62 mm ² because it is (0.675mm × 0.925mm), the luminance at laser emitting portion 68 is ^{1.6 × 10 6 (W / m} 2), 1 present optical fiber The luminance per hit is 3.2 × 10 ⁶ (W / m ² ).

On the other hand, when the light irradiating means is a means capable of irradiating the combined laser light, an output of about 1 W can be obtained with six multimode optical fibers, and the light emitting area of the laser emitting portion 68 can be obtained. Since the area is 0.0081 mm ² (0.325 mm × 0.025 mm), the luminance at the laser emitting portion 68 is 123 × 10 ⁶ (W / m ² ), which is about 80 times higher than the conventional luminance. Can be planned. Further, the luminance per optical fiber is 90 × 10 ⁶ (W / m ² ), and the luminance can be increased by about 28 times compared to the conventional one.

  Here, with reference to FIGS. 38A and 38B, the difference in the depth of focus between the conventional exposure head and the exposure head of the present embodiment will be described. The diameter of the light emission region of the bundled fiber light source of the conventional exposure head in the sub-scanning direction is 0.675 mm, and the diameter of the light emission region of the fiber array light source of the exposure head in the sub-scanning direction is 0.025 mm. As shown in FIG. 37A, in the conventional exposure head, since the light emitting area of the light irradiating means (bundle-shaped fiber light source) 1 is large, the angle of the light beam incident on the DMD 3 is increased, and as a result, the scanning surface 5 is moved. The angle of the incident light beam increases. For this reason, the beam diameter tends to increase with respect to the light condensing direction (shift in the focus direction).

  On the other hand, as shown in FIG. 37B, in the exposure head in the pattern forming apparatus, the diameter of the light emitting region of the fiber array light source 66 in the sub-scanning direction is small, so that the light flux that passes through the lens system 67 and enters the DMD 50 , And as a result, the angle of the light beam incident on the scanning surface 56 is reduced. That is, the depth of focus becomes deep. In this example, the diameter of the light emitting region in the sub-scanning direction is about 30 times that of the conventional one, and a depth of focus substantially corresponding to the diffraction limit can be obtained. Therefore, it is suitable for exposure of a minute spot. This effect on the depth of focus is more prominent and effective as the required light quantity of the exposure head is larger. In this example, the size of one pixel projected on the exposure surface is 10 μm × 10 μm. Note that DMD is a reflective spatial light modulator, but FIGS. 38A and 38B are developed views for explaining the optical relationship.

  Pattern information corresponding to the exposure pattern is input to a controller (not shown) connected to the DMD 50 and temporarily stored in a frame memory in the controller. This pattern information is data representing the density of each pixel constituting the image as binary values (whether or not dots are recorded).

  The stage 152 having the photosensitive solder resist film 150 having the photosensitive solder resist layer 150 adsorbed on the surface thereof is moved from the upstream side to the downstream side of the gate 160 along the guide 158 by a driving device (not shown) at a constant speed. When the leading edge of the photosensitive solder resist layer 150 is detected by the detection sensor 164 attached to the gate 160 when the stage 152 passes under the gate 160, the pattern information stored in the frame memory is sequentially stored for a plurality of lines. A control signal is generated for each exposure head 166 based on the pattern information read out and read out by the data processing unit. Then, each of the micromirrors of the DMD 50 is controlled on and off for each exposure head 166 based on the generated control signal by the mirror drive control unit.

  When the DMD 50 is irradiated with laser light from the fiber array light source 66, the laser light reflected when the micromirror of the DMD 50 is in the on state is reflected on the exposed surface 56 of the photosensitive solder resist layer 150 by the lens systems 54 and 58. Is imaged. In this way, the laser light emitted from the fiber array light source 66 is turned on / off for each pixel, and the photosensitive solder resist layer 150 is exposed in the same number of pixel units (exposure area 168) as the number of pixels used in the DMD 50. Is done. In addition, the photosensitive solder resist layer 150 is moved at a constant speed together with the stage 152, so that the photosensitive solder resist layer 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162. An exposed area 170 is formed.

<Microlens array>
The exposure is preferably performed through the microlens array with the modulated light, and may be performed through an aperture array, an imaging optical system, or the like.

  The microlens array is not particularly limited and may be appropriately selected depending on the purpose. For example, a microlens array having an aspherical surface capable of correcting aberration due to distortion of the exit surface in the pixel portion Are preferable.

  There is no restriction | limiting in particular as said aspherical surface, According to the objective, it can select suitably, For example, a toric surface is preferable.

  Hereinafter, the microlens array, the aperture array, the imaging optical system, and the like will be described with reference to the drawings.

14A shows the DMD 50, the light irradiation means 144 for irradiating the DMD 50 with laser light, the lens systems (imaging optical systems) 454, 458, and DMD 50 for enlarging and imaging the laser light reflected by the DMD 50. A microlens array 472 in which a large number of microlenses 474 are arranged corresponding to the picture element portion, an aperture array 476 in which a large number of apertures 478 are provided corresponding to each microlens of the microlens array 472, and a laser that has passed through the aperture An exposure head composed of lens systems (imaging optical systems) 480 and 482 for forming an image of light on an exposed surface 56 is shown.
Here, FIG. 15 shows the result of measuring the flatness of the reflecting surface of the micromirror 62 constituting the DMD 50. In the figure, the same height position of the reflecting surface is shown by connecting with a contour line, and the pitch of the contour line is 5 nm. Note that the x direction and the y direction shown in the figure are two diagonal directions of the micromirror 62, and the micromirror 62 rotates around the rotation axis extending in the y direction as described above. FIGS. 16A and 16B show the height position displacement of the reflecting surface of the micromirror 62 along the x direction and the y direction, respectively.

  As shown in FIGS. 15 and 16, there is distortion on the reflection surface of the micromirror 62, and when attention is particularly paid to the center of the mirror, distortion in one diagonal direction (y direction) is different from that in the other diagonal line. It is larger than the distortion in the direction (x direction). For this reason, the problem that the shape in the condensing position of the laser beam B condensed with the micro lens 55a of the micro lens array 55 may be distorted may occur.

  In the permanent pattern forming method of the present invention, in order to prevent the above problem, the microlens 55a of the microlens array 55 has a special shape different from the conventional one. Hereinafter, this point will be described in detail.

  FIGS. 17A and 17B respectively show the front and side shapes of the entire microlens array 55 in detail. These drawings also show the dimensions of each part of the microlens array 55, and the unit thereof is mm. In the permanent pattern forming method of the present invention, as described above with reference to FIG. 5, the 1024 × 256 rows of micromirrors 62 of the DMD 50 are driven. A row of 1024 microlenses 55a arranged in the horizontal direction is arranged in parallel in the vertical direction. In FIG. 9A, the arrangement order of the microlens array 55 is indicated by j in the horizontal direction and k in the vertical direction.

  18A and 18B show the front shape and the side shape of one microlens 55a in the microlens array 55, respectively. In FIG. 9A, contour lines of the microlens 55a are also shown. The end surface of each microlens 55a on the light emitting side has an aspherical shape that corrects aberration due to distortion of the reflecting surface of the micromirror 62. More specifically, the micro lens 55a is a toric lens, and has a radius of curvature Rx = −0.125 mm in a direction optically corresponding to the x direction and a radius of curvature Ry = − in a direction corresponding to the y direction. 0.1 mm.

  Therefore, the condensing state of the laser beam B in the cross section parallel to the x direction and the y direction is roughly as shown in FIGS. 19A and 19B, respectively. That is, when the cross section parallel to the x direction is compared with the cross section parallel to the y direction, the radius of curvature of the microlens 55a is smaller and the focal length is shorter in the latter cross section. .

  20A, 20B, 20C, and 20D show the results of simulating the beam diameter in the vicinity of the condensing position (focal position) of the microlens 55a when the microlens 55a has the above-described shape by a computer. For comparison, FIGS. 21A, 21B, 21C, and 21D show the results of a similar simulation when the microlens 55a has a spherical shape with a radius of curvature Rx = Ry = −0.1 mm. In addition, the value of z in each figure has shown the evaluation position of the focus direction of the micro lens 55a with the distance from the beam emission surface of the micro lens 55a.

The surface shape of the microlens 55a used for the simulation is calculated by the following calculation formula.

  In the above formula, Cx means the curvature in the x direction (= 1 / Rx), Cy means the curvature in the y direction (= 1 / Ry), and X is the lens optical axis in the x direction. The distance from O means Y, and Y means the distance from the lens optical axis O in the y direction.

  20A to 20D and FIGS. 21A to 21D, in the permanent pattern forming method of the present invention, the microlens 55a has a focal length in the cross section parallel to the y direction in the cross section parallel to the x direction. By using a toric lens that is smaller than the focal length, distortion of the beam shape in the vicinity of the condensing position is suppressed. If so, a higher-definition image without distortion can be exposed to the photosensitive solder resist layer 150. It can also be seen that the present embodiment shown in FIGS. 20a to 20d has a wider region with a smaller beam diameter, that is, a greater depth of focus.

  In addition, when the magnitude relation of the distortion of the center part in the x direction and the y direction of the micromirror 62 is opposite to the above, the focal length in the cross section parallel to the x direction is in the cross section parallel to the y direction. If the microlens is composed of a toric lens that is smaller than the focal length, similarly, a higher-definition image without distortion can be exposed to the photosensitive solder resist layer 150.

  In addition, the aperture array 59 disposed in the vicinity of the condensing position of the microlens array 55 is disposed such that only light having passed through the corresponding microlens 55a is incident on each aperture 59a. That is, by providing this aperture array 59, it is possible to prevent light from adjacent microlenses 55a not corresponding to each aperture 59a from entering, and to increase the extinction ratio.

  Originally, if the diameter of the aperture 59a of the aperture array 59 installed for the above purpose is reduced to some extent, an effect of suppressing the distortion of the beam shape at the condensing position of the microlens 55a can be obtained. However, in such a case, the amount of light blocked by the aperture array 59 is increased, and the light use efficiency is reduced. On the other hand, when the microlens 55a has an aspherical shape, the light utilization efficiency is kept high because the light is not blocked.

  In the permanent pattern forming method of the present invention, the microlens 55a may have a secondary aspherical shape or a higher order (4th, 6th,...) Aspherical shape. Good. By adopting the higher order aspherical shape, the beam shape can be further refined.

  In the embodiment described above, the end surface on the light emission side of the micro lens 55a is an aspherical surface (toric surface). However, one of the two light passing end surfaces is a spherical surface and the other is a cylindrical surface. Thus, the microlens array can be configured to obtain the same effect as the above embodiment.

  Furthermore, in the embodiment described above, the microlens 55a of the microlens array 55 has an aspherical shape that corrects aberration due to distortion of the reflecting surface of the micromirror 62. Such an aspherical shape is adopted. Instead, the same effect can be obtained even if each microlens constituting the microlens array has a refractive index distribution that corrects aberration due to distortion of the reflection surface of the micromirror 62.

  An example of such a microlens 155a is shown in FIG. (A) and (B) of the same figure respectively show the front shape and side shape of the micro lens 155a, and the external shape of the micro lens 155a is a parallel plate shape as shown in the figure. The x and y directions in the figure are as described above.

  24A and 24B schematically show the condensing state of the laser beam B in the cross section parallel to the x direction and the y direction by the microlens 155a. The microlens 155a has a refractive index distribution that gradually increases outward from the optical axis O. In the drawing, the broken line shown in the microlens 155a indicates that the refractive index is predetermined from the optical axis O, etc. The position changed with pitch is shown. As shown in the figure, when the cross section parallel to the x direction and the cross section parallel to the y direction are compared, the ratio of the refractive index change of the microlens 155a is larger in the latter cross section, and the focal length is larger. It is shorter. Even when a microlens array composed of such a gradient index lens is used, it is possible to obtain the same effect as when the microlens array 55 is used.

  In addition, in the microlens whose surface shape is aspherical like the microlens 55a previously shown in FIGS. 18 and 19, the refractive index distribution as described above is given together, and both by the surface shape and the refractive index distribution. The aberration due to the distortion of the reflection surface of the micromirror 62 may be corrected.

  In the above embodiment, the aberration due to the distortion of the reflection surface of the micromirror 62 constituting the DMD 50 is corrected. However, in the permanent pattern forming method of the present invention using a spatial light modulation element other than the DMD, the spatial When there is distortion on the surface of the picture element portion of the light modulation element, the present invention can be applied to correct the aberration caused by the distortion and prevent the beam shape from being distorted.

Next, the imaging optical system will be further described.
In the exposure head, when the laser beam is irradiated from the light irradiation means 144, the cross-sectional area of the beam line reflected in the ON direction by the DMD 50 is enlarged several times (for example, two times) by the lens systems 454 and 458. The The enlarged laser light is condensed by each microlens of the microlens array 472 so as to correspond to each pixel part of the DMD 50 and passes through the corresponding aperture of the aperture array 476. The laser light that has passed through the aperture is imaged on the exposed surface 56 by the lens systems 480 and 482.

  In this imaging optical system, the laser light reflected by the DMD 50 is magnified several times by the magnifying lenses 454 and 458 and projected onto the exposed surface 56, so that the entire image area is widened. At this time, if the microlens array 472 and the aperture array 476 are not arranged, as shown in FIG. 14B, one pixel size (spot size) of each beam spot BS projected onto the exposed surface 56 is set. MTF (Modulation Transfer Function) characteristics representing the sharpness of the exposure area 468 are reduced depending on the size of the exposure area 468.

  On the other hand, when the microlens array 472 and the aperture array 476 are arranged, the laser light reflected by the DMD 50 is condensed corresponding to each pixel part of the DMD 50 by each microlens of the microlens array 472. Thereby, as shown in FIG. 14C, even when the exposure area is enlarged, the spot size of each beam spot BS can be reduced to a desired size (for example, 10 μm × 10 μm), and the MTF characteristic is obtained. It is possible to perform high-definition exposure while preventing a decrease in the image quality. The exposure area 468 is tilted because the DMD 50 is tilted and arranged in order to eliminate the gap between the pixels.

  In addition, the aperture array can shape the beam so that the spot size on the surface to be exposed 56 is constant even if the beam is thick due to the aberration of the micro lens. Thus, crosstalk between adjacent picture elements can be prevented by passing through the aperture array.

  Further, by using a high-intensity light source, which will be described later, as the light irradiating means 144, the angle of the light beam incident on each microlens of the microlens array 472 from the lens 458 becomes small. The incident can be prevented. That is, a high extinction ratio can be realized.

<Other optical systems>
In the permanent pattern forming method of the present invention, it may be used in combination with other optical systems appropriately selected from known optical systems, for example, a light quantity distribution correcting optical system composed of a pair of combination lenses.
The light amount distribution correcting optical system changes the light flux width at each exit position so that the ratio of the light flux width at the peripheral portion to the light flux width at the central portion close to the optical axis is smaller on the exit side than on the incident side. When the DMD is irradiated with the parallel light beam from the light irradiation means, the light amount distribution on the irradiated surface is corrected so as to be substantially uniform. Hereinafter, the light quantity distribution correcting optical system will be described with reference to the drawings.

  First, as shown in FIG. 25A, the case where the entire luminous flux widths (total luminous flux widths) H0 and H1 are the same for the incident luminous flux and the outgoing luminous flux will be described. In FIG. 25A, the portions denoted by reference numerals 51 and 52 virtually indicate the entrance surface and the exit surface in the light quantity distribution correction optical system.

  In the light quantity distribution correcting optical system, it is assumed that the light flux widths h0 and h1 of the light beam incident on the central portion near the optical axis Z1 and the light flux incident on the peripheral portion are the same (h0 = hl). The light quantity distribution correcting optical system expands the light flux width h0 of the incident light flux at the central portion with respect to the light having the same light flux width h0, h1 on the incident side, and conversely changes the incident light flux at the peripheral portion. On the other hand, the light beam width h1 is reduced. That is, the width h10 of the outgoing light beam at the center and the width h11 of the outgoing light beam at the periphery are set to satisfy h11 <h10. In terms of the ratio of the luminous flux width, the ratio “h11 / h10” of the luminous flux width in the peripheral portion to the luminous flux width in the central portion on the emission side is smaller than the ratio (h1 / h0 = 1) on the incident side ( (H11 / h10) <1).

  By changing the light flux width in this way, the light flux in the central part, which normally has a large light quantity distribution, can be utilized in the peripheral part where the light quantity is insufficient, and the overall light utilization efficiency is not reduced. In addition, the light quantity distribution on the irradiated surface is made substantially uniform. For example, the degree of uniformity is preferably set so that the unevenness in the amount of light in the effective region is within 30% and within 20%.

  The operations and effects of the light quantity distribution correcting optical system are the same when the entire light beam width is changed between the incident side and the exit side (FIGS. 25B and 25C).

  FIG. 25B shows a case where the entire light flux width H0 on the incident side is “reduced” to the width H2 and emitted (H0> H2). Even in such a case, the light quantity distribution correcting optical system has the same light beam width h0, h1 on the incident side, and the light beam width h10 in the central part is larger than that in the peripheral part on the emission side. Conversely, the luminous flux width h11 at the peripheral part is made smaller than that at the central part. Considering the reduction rate of the light beam, the reduction rate with respect to the incident light beam in the central part is made smaller than that in the peripheral part, and the reduction rate with respect to the incident light beam in the peripheral part is made larger than that in the central part. Also in this case, the ratio “H11 / H10” of the light flux width in the peripheral portion to the light flux width in the central portion is smaller than the ratio (h1 / h0 = 1) on the incident side ((h11 / h10) <1). .

  FIG. 25C shows a case where the entire light flux width H0 on the incident side is “enlarged” by the width Η3 and emitted (H0 <H3). Even in such a case, the light quantity distribution correcting optical system has the same light beam width h0, h1 on the incident side, and the light beam width h10 in the central part is larger than that in the peripheral part on the emission side. Conversely, the luminous flux width h11 at the peripheral part is made smaller than that at the central part. Considering the expansion rate of the light beam, the expansion rate for the incident light beam in the central portion is made larger than that in the peripheral portion, and the expansion rate for the incident light beam in the peripheral portion is made smaller than that in the central portion. Also in this case, the ratio “h11 / h10” of the light flux width in the peripheral portion to the light flux width in the central portion is smaller than the ratio (h1 / h0 = 1) on the incident side ((h11 / h10) <1). .

  As described above, the light quantity distribution correcting optical system changes the light beam width at each emission position, and the ratio of the light beam width in the peripheral part to the light beam width in the central part near the optical axis Z1 is larger on the outgoing side than on the incident side. Since the light having the same luminous flux width on the incident side is larger on the outgoing side, the luminous flux width in the central portion is larger than that in the peripheral portion, and the luminous flux width in the peripheral portion is smaller than that in the central portion. Become smaller. As a result, it is possible to make use of the light beam at the center part to the peripheral part, and it is possible to form a light beam cross-section with a substantially uniform light amount distribution without reducing the light use efficiency of the entire optical system.

Next, an example of specific lens data of a pair of combination lenses used as the light amount distribution correcting optical system will be shown. In this example, lens data in the case where the light amount distribution in the cross section of the emitted light beam is a Gaussian distribution as in the case where the light irradiation means is a laser array light source is shown. When one semiconductor laser is connected to the incident end of the single mode optical fiber, the light quantity distribution of the emitted light beam from the optical fiber becomes a Gaussian distribution. The permanent pattern forming method of the present invention can be applied to such a case. Further, the present invention can be applied to a case where the light amount in the central part near the optical axis is larger than the light quantity in the peripheral part by reducing the core diameter of the multimode optical fiber and approaching the configuration of the single mode optical fiber.
Table 1 below shows basic lens data.

  As can be seen from Table 1, the pair of combination lenses is composed of two rotationally symmetric aspherical lenses. If the light incident side surface of the first lens disposed on the light incident side is the first surface and the light exit side surface is the second surface, the first surface is aspherical. In addition, when the surface on the light incident side of the second lens disposed on the light emitting side is the third surface and the surface on the light emitting side is the fourth surface, the fourth surface is aspherical.

In Table 1, the surface number Si indicates the number of the i-th surface (i = 1 to 4), the curvature radius ri indicates the curvature radius of the i-th surface, and the surface interval di indicates the i-th surface and the i + 1-th surface. The distance between surfaces on the optical axis is shown. The unit of the surface interval di value is millimeter (mm). The refractive index Ni indicates the value of the refractive index with respect to the wavelength of 405 nm of the optical element having the i-th surface.
Table 2 below shows the aspheric data of the first surface and the fourth surface.

  The aspherical data is represented by a coefficient in the following mathematical formula (A) representing the aspherical shape.

In the above formula (A), each coefficient is defined as follows.
Z: Length of a perpendicular line (mm) drawn from a point on the aspheric surface at a height ρ from the optical axis to the tangent plane (plane perpendicular to the optical axis) of the apex of the aspheric surface
ρ: Distance from optical axis (mm)
K: Conic coefficient C: Paraxial curvature (1 / r, r: Paraxial radius of curvature)
ai: i-th order (i = 3 to 10) aspheric coefficient In the numerical values shown in Table 2, the symbol “E” indicates that the next numerical value is a “power exponent” with 10 as the base. The numerical value represented by the exponential function with the base 10 is multiplied by the numerical value before “E”. For example, “1.0E-02” indicates “1.0 × 10 ⁻² ”.

  FIG. 27 shows a light amount distribution of illumination light obtained by the pair of combination lenses shown in Tables 1 and 2. The horizontal axis indicates coordinates from the optical axis, and the vertical axis indicates the light amount ratio (%). For comparison, FIG. 26 shows a light amount distribution (Gaussian distribution) of illumination light when correction is not performed. As can be seen from FIG. 26 and FIG. 27, a light amount distribution that is substantially uniform is obtained by performing correction using the light amount distribution correcting optical system as compared with the case where correction is not performed. Thereby, it is possible to perform exposure with uniform laser light without reducing the use efficiency of light, without causing any unevenness.

-Development process-
The developing step exposes the photosensitive solder resist layer in the exposing step, cures the exposed area of the photosensitive solder resist layer, and then develops the uncured area by developing to form a permanent pattern. It is a process to do.

  There is no restriction | limiting in particular as the removal method of the said unhardened area | region, According to the objective, it can select suitably, For example, the method etc. which remove using a developing solution are mentioned.

  The developer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, alkali metal or alkaline earth metal hydroxide or carbonate, hydrogen carbonate, aqueous ammonia, quaternary ammonium salt An aqueous solution of Among these, an aqueous sodium carbonate solution is particularly preferable.

  The developer includes a surfactant, an antifoaming agent, an organic base (for example, benzylamine, ethylenediamine, ethanolamine, tetramethylammonium hydroxide, diethylenetriamine, triethylenepentamine, morpholine, triethanolamine, etc.) May be used in combination with an organic solvent (for example, alcohols, ketones, esters, ethers, amides, lactones, etc.). The developer may be an aqueous developer obtained by mixing water or an aqueous alkali solution and an organic solvent, or may be an organic solvent alone.

[Curing process]
The permanent pattern forming method of the present invention preferably further includes a curing treatment step.
The curing treatment step is a step of performing a curing treatment on the photosensitive solder resist layer in the formed permanent pattern after the development step is performed.

  There is no restriction | limiting in particular as said hardening process, According to the objective, it can select suitably, For example, a whole surface exposure process, a whole surface heat processing, etc. are mentioned suitably.

Examples of the entire surface exposure processing method include a method of exposing the entire surface of the laminate on which the permanent pattern is formed after the developing step. By the entire surface exposure, curing of the resin in the photosensitive solder resist composition for forming the photosensitive solder resist layer is promoted, and the surface of the permanent pattern is cured.
There is no restriction | limiting in particular as an apparatus which performs the said whole surface exposure, According to the objective, it can select suitably, For example, UV exposure machines, such as an ultrahigh pressure mercury lamp, are mentioned suitably.

Examples of the entire surface heat treatment method include a method of heating the entire surface of the laminate on which the permanent pattern is formed after the developing step. By heating the entire surface, the film strength of the surface of the permanent pattern is increased.
As heating temperature in the said whole surface heating, 120-250 degreeC is preferable and 120-200 degreeC is more preferable. When the heating temperature is less than 120 ° C., the film strength may not be improved by heat treatment. When the heating temperature exceeds 250 ° C., the resin in the photosensitive solder resist composition is decomposed and the film quality is weak. May become brittle.
As heating time in the said whole surface heating, 10 to 120 minutes are preferable and 15 to 60 minutes are more preferable.
There is no restriction | limiting in particular as an apparatus which performs the said whole surface heating, According to the objective, it can select suitably from well-known apparatuses, For example, a dry oven, a hot plate, IR heater etc. are mentioned.

When the substrate is a printed wiring board such as a multilayer wiring board, the permanent pattern of the present invention can be formed on the printed wiring board, and further soldered as follows.
That is, the development step forms a hardened layer that is the permanent pattern, and the metal layer is exposed on the surface of the printed wiring board. Gold plating is performed on the portion of the metal layer exposed on the surface of the printed wiring board, and then soldering is performed. Then, a semiconductor or a component is mounted on the soldered portion. At this time, the permanent pattern by the hardened layer exhibits a function as a protective film or an insulating film (interlayer insulating film), and prevents external impact and conduction between adjacent electrodes.

  In the permanent pattern forming method of the present invention, it is preferable to form at least one of a protective film and an interlayer insulating film. When the permanent pattern formed by the permanent pattern forming method is the protective film or the interlayer insulating film, the wiring can be protected from external impact and bending, particularly when the interlayer insulating film is the interlayer insulating film. Is useful for high-density mounting of semiconductors and components on, for example, multilayer wiring boards and build-up wiring boards.

The permanent pattern forming method of the present invention can be widely used for forming various patterns because the pattern can be formed at a high speed, and can be particularly suitably used for forming a wiring pattern.
In addition, the permanent pattern formed by the method for forming a permanent pattern of the present invention has excellent surface hardness, insulation, heat resistance, moisture resistance, etc., and is suitably used as a protective film, interlayer insulation film, solder resist pattern, etc. can do.

  Examples of the present invention will be described below, but the present invention is not limited to the following examples.

  (Meth) acrylamide copolymers (AP-1) to (AP-7) (Synthesis Examples 1 to 7) included in the photosensitive solder resist compositions of Examples, and included in the photosensitive solder resist compositions of Comparative Examples. (Meth) acrylamide copolymers (AP-8) to (AP-14) (Synthesis Examples 8 to 14) Alkali-soluble photocrosslinkable resins (PP-1) to (PP-2) (Synthesis Examples 15 to 16), Preparation of pigment and inorganic filler dispersion (Synthesis Example 17) was synthesized as follows.

(Synthesis Example 1) Synthesis of (meth) acrylamide copolymer (AP-1) 100 parts by mass of methoxypropyl acetate was charged in a four-flask and kept at 90 ° C., nitrogen sealing and methyl methacrylate while stirring. 25 parts by mass, 20 parts by mass of styrene, 40 parts by mass of N-tert-butylmethacrylamide, 15 parts by mass of methacrylic acid, 1.6 parts by mass of n-dodecyl mercaptan, and 2,2′-azobisisobutyronitrile 1.8 The mass part was mixed and it was dripped over 30 minutes with the dropping funnel. Thereafter, the reaction was continued for 4 hours. After returning to room temperature, methoxypropyl acetate was diluted with 50 parts by mass such that the solid content concentration was 40% by mass to obtain a (meth) acrylamide copolymer (AP-1). (AP-1) had a solid content acid value of 98 mgKOH / g and a mass average molecular weight of 45,000.

(Synthesis Examples 2 to 14) Synthesis of (Meth) acrylamide Copolymers (AP-2) to (AP-14) In the same manner as in Synthesis Example 1, each copolymer composition as shown in Table 3 or Table 4 ( Meth) acrylamide polymers (AP-2) to (AP-14) were synthesized.

Synthesis Example 15 Synthesis of Alkali-Soluble Photocrosslinkable Resin (PP-1) 220 parts by mass of YDCN704 (manufactured by Toto Kasei Co., Ltd., cresol novolac type epoxy resin (epoxy equivalent = 220)), 72 parts by mass of acrylic acid, hydroquinone 1.0 part by mass and 180 parts by mass of methoxypropyl acetate were charged, heated to 90 ° C. and stirred to dissolve the reaction mixture. Next, the mixture was cooled to 60 ° C., charged with 1 part by mass of benzyltrimethylammonium chloride, heated to 100 ° C., and reacted until the solid content acid value reached 1 mgKOH / g. Next, 152 parts by mass of tetrahydrophthalic anhydride and 100 parts by mass of methoxypropyl acetate are added, heated to 80 ° C., reacted for about 6 hours, cooled, and diluted with methoxypropyl acetate so that the solid content concentration becomes 60% by mass. Thus, an alkali-soluble photocrosslinkable resin (PP-1) was obtained. The solid content acid value of (PP-1) was 138 mgKOH / g, and the mass average molecular weight was 4,020.

(Synthesis Example 16) Synthesis of Alkali-Soluble Photocrosslinkable Resin (PP-2) 100 parts by mass of methoxypropyl acetate was charged in a four-flask and kept at 90 ° C. while nitrogen sealing and stirring. .1 part by mass, 47.3 parts by mass of methacrylic acid, 1.6 parts by mass of n-dodecyl mercaptan, and 1.8 parts by mass of 2,2′-azobisisobutyronitrile were mixed in a dropping funnel over 30 minutes. It was dripped. Thereafter, the reaction was continued for 4 hours, and then the nitrogen sealing was stopped, and 0.15 parts by mass of hydroquinone monomethyl ether and 0.45 parts by mass of dimethylbenzylamine were added. Reaction was performed by adding dropwise 58.9 parts by mass of 3,4-epoxycyclohexylmethyl methacrylate over 30 minutes and stirring at 90 ° C. for 3 hours. After returning to room temperature, methoxypropyl acetate was diluted with 127 parts by mass so that the solid content concentration was 40% by mass to obtain an alkali-soluble photocrosslinkable resin (PP-2). The solid content acid value of (PP-2) was 93 mgKOH / g, and the mass average molecular weight was 22,000.

(Synthesis example 17) Preparation of pigment and inorganic filler co-dispersion liquid Pigment Blue 15: 3 0.80 parts by mass, Pigment Yellow 180 0.7 parts by mass, 60% by mass of each alkali-soluble photocrosslinkable resin 15 parts by mass of the methoxypropyl acetate solution was weighed and dispersed using a mill type disperser filled with zirconia beads to obtain a green pigment dispersion.
Subsequently, 18 parts by mass of barium sulfate as an inorganic filler was mixed and stirred in the green pigment dispersion to obtain 81.4 parts by mass of a co-dispersion with a green pigment (solid content concentration 35% by mass).

Example 1
<Preparation of photosensitive solder resist composition coating solution>
The following components (see Table 3) were mixed to prepare a photosensitive solder resist composition coating solution.
―――――――――――――――――――――――――――――――――――――――
Alkali-soluble photocrosslinkable resin (PP-1) solution (solid content concentration 60% by mass) ... 39.3 parts by mass Alkali-soluble photocrosslinkable Resin (PP-2) solution (solid content concentration 60% by mass) ... 39.3 parts by mass (meth) acrylamide copolymer (AP- 1) Solution (solid content concentration 40% by mass) ... 47.2 parts by mass Bisphenol A type epoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., Epicoat 1004) 14.3 parts by mass Dipentaerythritol hexaacrylate (DPHA manufactured by Nippon Kayaku Co., Ltd.) ... 18.9 parts by mass Part N- (n-Butyl) -2-chloroacridone ... 2.2 Part 2-benzyl-2-dimethylamino-1- (morpholinophenyl) - butan-1-one (Ciba Specialty Chemicals Corp., Irgacure 369) · · · · ·
・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 4.9 parts by mass Pigment and inorganic filler co-dispersion (Synthesis Example 17) ) ... 81.4 parts by mass Dicyandiamide ... 0.7 parts by mass Fluorine-based Surfactant (manufactured by Dainippon Ink, F780F) ... 0.07 parts by mass Hydroquinone monomethyl ether ... 0.066 parts by mass ―――――――――――――――――――――――――――――――――――

-Production of photosensitive solder resist film-
As shown in FIG. 1, a polyethylene terephthalate film having a thickness of 25 μm (Lumirror 16QS52 manufactured by Toray Industries, Inc.) is used as the support 1, and the photosensitive solder resist composition coating solution is dried on the support 1 by a bar coater. The subsequent photosensitive solder resist layer 2 was applied to a thickness of about 30 μm, dried in a hot air circulating drier at 80 ° C. for 30 minutes, and then the protective film was coated on the photosensitive solder resist layer. No. 3, a polypropylene film having a thickness of 12 μm was laminated by lamination to produce a photosensitive solder resist film.

-Formation of permanent pattern-
-Preparation of laminate-
The substrate was prepared by subjecting a surface of a copper-clad laminate (no through-hole, printed wiring board with a copper thickness of 12 μm) to which a wiring had been formed, subjected to chemical polishing. A vacuum laminator (Nichigo Morton (Nichigo) (VP Co., Ltd.) was used to prepare a laminate in which the copper-clad laminate, the photosensitive solder resist layer, and the polyethylene terephthalate film (support) were laminated in this order.
The pressure bonding conditions were a vacuum drawing time of 40 seconds, a pressure bonding temperature of 70 ° C., a pressure bonding pressure of 0.2 MPa, and a pressure application time of 10 seconds.

--Exposure process--
A 405 nm laser beam is applied to the photosensitive solder resist layer in the prepared laminate from a polyethylene terephthalate film (support) side using a pattern forming apparatus by blue-violet laser exposure having a predetermined pattern. Was irradiated with an energy amount of 35 mJ / cm ² and exposed to cure a part of the photosensitive solder resist layer.

--Development process--
The exposed laminate was allowed to stand at room temperature for 10 minutes, and then the polyethylene terephthalate film (support) was peeled off from the laminate, and an alkaline developer was applied to the entire surface of the photosensitive solder resist layer on the copper clad laminate. As an example, spray development was performed using a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 60 seconds at a pressure of 0.18 MPa (1.8 kgf / cm ² ) to dissolve and remove unexposed areas. Thereafter, it was washed with water and dried to form a permanent pattern.

-Curing process-
The entire surface of the laminate on which the permanent pattern was formed was heat treated at 150 ° C. for 1 hour to cure the surface of the permanent pattern and increase the film strength.
According to the permanent pattern resist thus obtained, the insulation resistance after being left for 168 hours in an environment having the above composition and a temperature of 85 ° C. and a relative humidity of 85% is processed to be 10 ¹⁰ Ω or more. Therefore, even when used in a high temperature and high humidity atmosphere, the wiring conductor layers are not short-circuited, and the wiring conductor layers are not corroded, and are excellent in moisture resistance. Further, since the obtained printed wiring board is formed by depositing a wiring conductor layer on the surface of the insulating substrate and covering the part of the insulating substrate, the permanent pattern is deposited. However, it is possible to protect the insulating layer from heat when mounting electronic components on a printed wiring board, and to protect the wiring conductor layer from oxidation and corrosion due to moisture. As a result, the heat resistance and moisture resistance are excellent.

[Evaluation]
In the photosensitive solder resist film, laminate, and permanent pattern obtained in Example 1, with respect to the photosensitive solder resist film and laminate, the protective film peelability, support peelability, and sensitivity were as follows. , Resolution, developability, and storage stability were evaluated.
The permanent pattern was evaluated for pattern cross-sectional shape, insulation resistance test, impact resistance, adhesion, solvent resistance, alkali resistance, solder heat resistance, gold plating resistance, and pencil hardness under the following conditions. . The results obtained are shown in Tables 5 and 6.

<Protective film peelability>
In the step of removing the protective film from the photosensitive solder resist film, a practical sensory test and measurement of the peeling force were performed.
The measurement of the peel strength of the protective film is in accordance with JIS K-6854-2. Specifically, a sample cut out from a photosensitive solder resist film into a width of 4.5 cm and a length of 8 cm is used as the surface of the protective film. The film was fixed on the pedestal with double-sided tape, and the peel strength between the photosensitive layer and the protective film when the protective film was peeled off from the sample at a pulling speed of 160 cm / min using a force gauge was determined. . The measurement was performed 5 times and expressed as an average value.
-Evaluation criteria for protective film peelability sensory test-
○: There is no sound and it peels with little resistance.
Δ: There is a slight resistance when peeling, and a peeling sound is produced.
X: Not peeled off (forcible peeling causes cohesive failure of the photosensitive solder resist layer or peeling between the support / photosensitive solder resist layer).

<Support peelability>
In the step of peeling the support after exposure to the photosensitive solder resist film, after forming the copper-clad substrate photosensitive solder resist film laminate, cooling to room temperature without pattern exposure, and then performing a practical peelable sensory test and peeling. Force measurements were taken.
The peel strength of the support is measured in accordance with JIS K-6854-2. Specifically, a sample cut into a width 4.5 cm × length 8 cm from a laminate sample of a photosensitive solder resist film and a copper-clad laminate. And a photosensitive solder resist layer when the support is peeled off from the sample at a pulling speed of 160 cm / min using a force gauge. The peel strength from the protective film was measured and determined. The measurement was performed 5 times and expressed as an average value.
-Evaluation criteria for peelable sensory test-
○: There is no sound and it peels with little resistance.
Δ: There is a slight resistance when peeling, and a peeling sound is produced.
X: Not peeled off (If peeled off forcibly, cohesive failure of the photosensitive layer occurs).

<Sensitivity and resolution>
(1) Measurement of shortest development time The polyethylene terephthalate film (support) is peeled off from the laminate, and a 1 mass% sodium carbonate aqueous solution at 30 ° C. is added to the entire surface of the photosensitive solder resist layer on the copper clad laminate. Spraying was performed at a pressure of 15 MPa, and the time required from the start of spraying of the aqueous sodium carbonate solution until the photosensitive solder resist layer on the copper-clad laminate was dissolved and removed was measured, and this was taken as the shortest development time.

(2) Measurement of sensitivity The pattern forming apparatus having a 405 nm laser light source as the light irradiating means from the polyethylene terephthalate film (support) side with respect to the photosensitive layer of the pattern forming material in the laminated body was set to 0. Exposure was performed by irradiating with different light energy amounts ranging from 1 mJ / cm ² to 100 mJ / cm ² at 2 ^1/2 times intervals to cure a part of the photosensitive solder resist layer. After standing at room temperature for 10 minutes, the polyethylene terephthalate film (support) was peeled off from the laminate, and an aqueous sodium carbonate solution (30 ° C., 1% by mass) was formed on the entire surface of the photosensitive solder resist layer on the copper clad laminate. ) Was sprayed at a spray pressure of 0.15 MPa for twice the minimum development time to dissolve and remove the uncured region, and the thickness of the portion other than the portion removed by development (cured region) was measured. Next, a sensitivity curve is obtained by plotting the relationship between the light irradiation amount and the thickness of the cured layer. From the sensitivity curve thus obtained, the amount of light energy when the thickness of the cured region was 30 μm was determined as the minimum amount of light energy (sensitivity) necessary for curing the photosensitive solder resist layer. The pattern forming apparatus includes a light modulating unit made of the DMD and includes the pattern forming material.

(3) Resolution measurement The laminated body is allowed to stand at room temperature (23 ° C., 55% RH) for 10 minutes, and the line is formed on the polyethylene terephthalate film (support) of the laminated body using the pattern forming apparatus. / Space = 1/1, line widths of 5 μm to 20 μm were exposed in 1 μm increments, and line widths of 20 μm to 50 μm were exposed in 5 μm increments. The exposure amount at this time is the minimum amount of light energy necessary for curing the photosensitive solder resist layer of the pattern forming material obtained by the sensitivity measurement. After standing at room temperature for 10 minutes, the polyethylene terephthalate film (support) was peeled off from the laminate. Spraying the entire surface of the photosensitive solder resist layer on the copper-clad laminate with an aqueous sodium carbonate solution (30 ° C., 1% by mass) as the developer at a spray pressure of 0.15 MPa for twice the shortest development time, Uncured areas were removed by dissolution. The surface of the copper-clad laminate with the cured resin pattern thus obtained was observed with an optical microscope, and the minimum line width without any abnormalities such as tsumari and twisting was measured on the cured resin pattern line. did. The smaller the numerical value, the better the resolution.

<Developability>
An unexposed photosensitive solder resist layer having a thickness of 10 μm on the substrate was spray-developed at 30 ° C. using a 1% by mass aqueous sodium carbonate solution and evaluated by whether it could be removed in 10 to 60 seconds.
○: Removed in 10 seconds to less than 60 seconds and no development residue.
X: Removed in less than 10 seconds.
XX: Development residue exists even after 60 seconds.

<Storage stability>
The laminate is sealed in a light-proof moisture-proof bag (BF3X manufactured by Tokai Aluminum Foil Co., Ltd.), stored in a constant temperature and humidity chamber under accelerated conditions (30 ° C., 90% RH) for 3 days, and developability over time. Changes were measured.
The storage stability was evaluated according to the following criteria from the value of the ratio (t ₀ / t _3d ) by comparing the initial shortest development time t ₀ and the shortest development time t _3d after the acceleration condition.
-Evaluation criteria-
○: 1 times or more and less than 2 times △: 2 times or more and less than 3 times (Available level)
×: 3 times or more

<Pattern cross-sectional shape>
The surface irregularity of the permanent pattern after curing was measured using a surface roughness measuring machine (Surfcom 1400D: manufactured by Tokyo Seimitsu Co., Ltd.) and evaluated based on the following criteria.
-Evaluation criteria-
○: Ra = less than 0.5 μm and excellent on the surface.
X: Ra = 0.5 μm or more and inferior on the surface.

<Insulation resistance>
Using IPC-B-25 comb-shaped test pattern B, wearing a photomask for pattern B, the entire surface was exposed at 40 mJ / cm ² by the blue-violet laser irradiation apparatus, and 1% by mass of carbonic acid at 30 ° C. for 60 seconds. Development, washing with water and drying with an aqueous sodium solution were carried out, and a test substrate was prepared by post-heating treatment at 150 ° C. for 1 hour. About the obtained test board | substrate, according to the test method of IPC-SM-840B, the insulation resistance in 25 degreeC and 50% RH was measured, and the following references | standards evaluated.
-Evaluation criteria-
○: Insulation resistance value is 5 × 10 ⁸ Ω or more ×: Insulation resistance value is less than 5 × 10 ⁸ Ω

<Heat shock resistance>
As a reliability test item, the appearance and the resistance value change rate of the permanent pattern after curing were evaluated by a temperature cycle test (TCT). TCT was performed using a vapor-phase cooling / heating tester, and the electronic component module was left in a vapor phase at temperatures of −55 ° C. and 125 ° C. for 30 minutes, and this was performed under the conditions of 1,000 cycles.
-Evaluation criteria-
○: No crack occurred ×: Crack occurred

<Adhesion>
According to JIS K5400, 100 1 mm grids were produced in the permanent pattern after curing, and a peel test was performed using a cellophane tape. The peeled state of the grid was observed and evaluated according to the following criteria.
-Evaluation criteria-
○: No peeling at 90/100 or more Δ: No peeling at 50/100 or more to less than 90/100 ×: No peeling at 0/100 to less than 50/100

<Solvent resistance>
The cured permanent pattern was immersed in isopropyl alcohol for 30 minutes at room temperature, and after confirming that there was no abnormality in appearance, a peel test was performed using a cellophane tape.
-Evaluation criteria-
○: No abnormality in the appearance of the coating film and no peeling.
X: The appearance of the coating film is abnormal or peels off.

<Acid resistance>
The cured permanent pattern was immersed in a 10% by mass aqueous hydrochloric acid solution at room temperature for 30 minutes, and after confirming that there was no abnormality in the appearance, a peel test was performed using a cellophane tape.
-Evaluation criteria-
○: No abnormality in the appearance of the coating film and no peeling.
X: The appearance of the coating film is abnormal or peels off.

<Alkali resistance>
The cured permanent pattern was immersed in a 5% by mass aqueous sodium hydroxide solution at room temperature for 30 minutes, and after confirming that there was no abnormality in appearance, a peel test was performed using a cellophane tape.
-Evaluation criteria-
○: No abnormality in the appearance of the coating film and no peeling.
X: The appearance of the coating film is abnormal or peels off.

<Solder heat resistance>
A rosin-based flux or a water-soluble flux was applied to the permanent pattern after curing, and was immersed in a solder bath at 260 ° C. for 10 seconds. This was defined as one cycle, and after repeating 6 cycles, the appearance of the coating film was visually observed.
-Evaluation criteria-
○: There is no abnormality (peeling, swelling) in the appearance of the coating film, and there is no solder peeling.
X: Abnormality (peeling, blistering) in the appearance of the coating film or solder peeling.

<Gold resistance>
The cured permanent pattern was immersed in an acidic degreasing solution (manufactured by Nihon McDermitt, 20 vol% aqueous solution of Metex L-5B) for 3 minutes, and then washed with water.
Next, after immersing in a 14.4% by volume aqueous ammonium persulfate solution at room temperature for 3 minutes, it was washed with water, and further immersed in a 10% by volume sulfuric acid aqueous solution at room temperature for 1 minute, followed by washing with water.
Next, this test substrate is immersed in a 30 ° C. catalyst solution (Meltex, 10 volume% aqueous solution of Melplate Activator 350) for 7 minutes, washed with water, and 85 ° C. nickel plating solution (Meltex, Melplate). Ni-865M 10 volume% sulfuric acid aqueous solution) was immersed for 1 minute at room temperature and then washed with water.
Next, the test substrate was immersed for 10 minutes in a gold plating solution at 95 ° C. (Meltex, 15% by volume of Aurolectroles UP and 3% by volume of potassium cyanide cyanide, pH 6), followed by electroless gold plating. This was washed with water, further immersed in warm water at 60 ° C. for 3 minutes, washed with water and dried. The obtained electroless gold plating evaluation board was observed and evaluated according to the following criteria.
-Evaluation criteria-
○: No abnormality at all.
X: Bad plating adhesion or dent due to plating was observed.

<Pencil hardness>
The cured permanent pattern was subjected to gold plating according to a conventional method and then subjected to a water-soluble flux treatment. Subsequently, it was immersed three times in a solder bath set at 260 ° C. for 5 seconds, and the flux was removed by washing with water. And the pencil hardness was measured about the permanent pattern after this flux removal based on JISK-5400.

(Examples 2 to 8 and Comparative Examples 1 to 11)
For Example 2 to Example 8 and Comparative Examples 1 to 11, as shown in Table 5, in Example 1, 47.2 parts by mass of (meth) acrylamide copolymer (AP-1) Each photosensitive solder resist composition was formulated in the same manner as in Example 1 except that each copolymer and content of (AP-2 to AP-14) obtained in (Synthesis Examples 2 to 14) were changed. The coating solution was adjusted, and subsequently a photosensitive solder resist film, a laminate, and a permanent pattern were formed.
About the obtained said photosensitive soldering resist film and the said laminated body, it carried out similarly to Example 1, and performed evaluation of peelability of a protective film, support body peelability, sensitivity, resolution, developability, and storage stability.
For the permanent pattern, evaluation of pattern cross-sectional shape, insulation resistance test, impact resistance, adhesion, solvent resistance, alkali resistance, solder heat resistance, gold plating resistance, and pencil hardness was performed in the same manner as in Example 1. Went. The results obtained are shown in Tables 5 and 6.

From the results shown in Table 5 and Table 6, by including the (meth) acrylamide copolymer of the present invention in the photosensitive solder resist composition, adhesion to the substrate is not deteriorated, and developability is improved. It was found that an excellent photosensitive solder resist composition capable of forming a highly reliable photosensitive solder resist layer can be obtained.
In addition, the photosensitive solder resist layer comprising the photosensitive solder resist composition is highly sensitive to blue-ultraviolet laser, and has insulation resistance, thermal shock resistance, adhesion, solvent resistance, acid resistance, alkali resistance, It has been found that a permanent pattern having good solder heat resistance, gold plating resistance, and pencil hardness can be formed.

  The photosensitive solder resist composition of the present invention and the photosensitive solder resist film using the photosensitive solder resist composition are excellent in peelability and storage stability of the support and protective film, and have excellent chemical resistance after development. Expresses surface hardness, heat resistance, etc. In addition, even if the permanent pattern (protective film, interlayer insulating film, solder resist, etc.) of the present invention is thinned, a high-definition permanent pattern excellent in surface hardness, insulation, heat resistance, and moisture resistance can be obtained. It can be used suitably as a protective film and interlayer insulation film, printed wiring boards (multilayer wiring boards, build-up wiring boards, etc.), color filters, pillar materials, rib materials, spacers, display members such as partition walls, holograms, It can be widely used for forming permanent patterns such as micromachines and proofs.

FIG. 1 is an explanatory view showing the layer structure of a photosensitive solder resist film. FIG. 2 is an example of a partially enlarged view showing a configuration of a digital micromirror device (DMD). 3A and 3B are examples of explanatory diagrams for explaining the operation of the DMD. FIGS. 4A and 4B are examples of plan views showing the arrangement of exposure beams and scanning lines in a case where the DMD is not inclined and in a case where the DMD is inclined. 5A and 5B are examples of diagrams illustrating examples of DMD usage areas. FIG. 6 is an example of a plan view for explaining an exposure method in which the photosensitive solder resist layer is exposed by one scanning by the scanner. FIGS. 7A and 7B are examples of plan views for explaining an exposure method in which the photosensitive solder resist layer is exposed by scanning a plurality of times by a scanner. FIG. 8 is an example of a schematic perspective view showing an appearance of an example of the pattern forming apparatus. FIG. 9 is an example of a schematic perspective view illustrating the configuration of the scanner of the pattern forming apparatus. FIG. 10A is an example of a plan view showing an exposed region formed in the photosensitive solder resist layer, and FIG. 10B is an example of a diagram showing an array of exposure areas by each exposure head. . FIG. 11 is an example of a perspective view showing a schematic configuration of an exposure head including a light modulation unit. FIG. 12 is an example of a sectional view in the sub-scanning direction along the optical axis showing the configuration of the exposure head shown in FIG. FIG. 13 is an example of a controller that controls DMD based on pattern information. FIG. 14A is an example of a cross-sectional view along the optical axis showing the configuration of another exposure head having a different coupling optical system, and FIG. 14B shows an object to be exposed when a microlens array or the like is not used. FIG. 14C is an example of a plan view showing an optical image projected on an exposed surface when a microlens array or the like is used. FIG. 15 is an example of a diagram showing the distortion of the reflection surface of the micromirror constituting the DMD with contour lines. FIGS. 16A and 16B are examples of graphs showing the distortion of the reflection surface of the micromirror in the two diagonal directions of the mirror. FIG. 17 is an example of a front view (A) and a side view (B) of a microlens array used in the pattern forming apparatus. FIG. 18 is an example of a front view (A) and a side view (B) of a microlens constituting a microlens array. FIG. 19 is an example of a schematic diagram illustrating a condensing state by a microlens in one cross section (A) and another cross section (B). FIG. 20a is an example of a diagram showing a result of simulating the beam diameter in the vicinity of the condensing position of the microlens. FIG. 20b is an example of a diagram showing the same simulation result as in FIG. 20a at another position. FIG. 20c is an example of a diagram showing the same simulation result as in FIG. 20a for another position. FIG. 20d is an example of a diagram illustrating simulation results similar to those in FIG. 20a at different positions. FIG. 21a is an example of a diagram showing a result of simulating the beam diameter in the vicinity of the condensing position of the microlens in the conventional pattern forming method. FIG. 21 b is an example of a diagram showing the same simulation result as in FIG. 21 a for another position. FIG. 21c is an example of a diagram showing the same simulation result as in FIG. 21a at another position. FIG. 21d is an example of a diagram showing the same simulation result as in FIG. 21a at another position. FIG. 22 is an example of a plan view showing another configuration of the combined laser light source. FIG. 23 is an example of a front view (A) and an example of a side view (B) of a microlens constituting a microlens array. FIG. 24 is an example of a schematic diagram illustrating a light collection state by the microlens of FIG. 23 in one cross section (A) and another cross section (B). FIGS. 25A, 25B, and 25C are examples of explanatory diagrams about the concept of correction by the light amount distribution correction optical system. FIG. 26 is an example of a graph showing the light amount distribution when the light irradiation means has a Gaussian distribution and the light amount distribution is not corrected. FIG. 27 is an example of a graph showing the light amount distribution after correction by the light amount distribution correcting optical system. 28A (A) is a perspective view showing the configuration of the fiber array light source, FIG. 28A (B) is an example of a partially enlarged view of (A), and FIGS. 28A (C) and (D) are lasers. It is an example of the top view which shows the arrangement | sequence of the light emission point in an emission part. FIG. 28 b is an example of a front view showing the arrangement of light emitting points in the laser emitting section of the fiber array light source. FIG. 29 is an example of a diagram illustrating a configuration of a multimode optical fiber. FIG. 30 is an example of a plan view showing the configuration of the combined laser light source. FIG. 31 is an example of a plan view showing the configuration of the laser module. FIG. 32 is an example of a side view illustrating the configuration of the laser module illustrated in FIG. 31. FIG. 33 is a partial side view showing the configuration of the laser module shown in FIG. FIG. 34 is an example of a perspective view showing a configuration of a laser array. FIG. 35A is an example of a perspective view showing a configuration of a multi-cavity laser, and FIG. 35B is a perspective view of a multi-cavity laser array in which the multi-cavity lasers shown in FIG. It is an example. FIG. 36 is an example of a plan view showing another configuration of the combined laser light source. FIG. 37A is an example of a plan view showing another configuration of the combined laser light source, and FIG. 37B is an example of a cross-sectional view taken along the optical axis of FIG. FIGS. 38A and 38B are examples of cross-sectional views along the optical axis showing the difference between the depth of focus in the conventional exposure apparatus and the depth of focus by the permanent pattern formation method (pattern formation apparatus) of the present invention. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support body 2 Photosensitive solder resist layer 3 Protective film LD1-LD7 GaN type semiconductor laser 10 Heat block 11-17 Collimator lens 20 Condensing lens 30-31 Multimode optical fiber 44 Collimator lens holder 45 Condensing lens holder 46 Fiber holder 50 Digital Micromirror Device (DMD)
52 Lens system 53 Reflected light image (exposure beam)
54 Lens of second imaging optical system 55 Micro lens array 56 Surface to be exposed (scanning surface)
55a Micro lens 57 Lens of second image forming optical system 58 Lens of second image forming optical system 59 Aperture array 64 Laser module 66 Fiber array light source 67 Lens system 68 Laser emitting portion 69 Mirror 70 Prism 73 Combination lens 74 Imaging lens 100 Heat block 110 Multicapacity laser 111 Heat block 113 Rod lens 120 Condensing lens 130 Multimode optical fiber 130a Core 140 Laser array 144 Light irradiation means 150 Photosensitive solder resist layer 152 Stage 155a Micro lens 156 Installation table 158 Guide 160 Gate 162 Scanner 164 Sensor 166 Exposure head 168 Exposure area 170 Exposed area 180 Heat block 184 Collimating lens array 30 Controller 304 stage driver 454 lens system 468 exposure area 472 microlens array 476 array of apertures 478 apertures 480 lens system

Claims (21)

A photosensitive solder resist composition comprising an alkali-soluble photocrosslinkable resin, a polymerizable compound, a photopolymerization initiator, a thermal crosslinking agent, a thermosetting accelerator, and a colorant,
Further, a (meth) acrylamide copolymer having an acid value of 90 to 200 mg KOH / g and a weight average molecular weight of 30,000 to 80,000 (excluding those having a self-condensable group as a substituent) is described above. A photosensitive solder resist composition comprising 15 to 50% by mass of an alkali-soluble photocrosslinkable resin.   The photosensitive solder resist composition according to claim 1, wherein the (meth) acrylamide copolymer has a glass transition temperature (Tg) of 420 K or higher. The photosensitive solder resist composition according to claim 1, wherein the (meth) acrylamide copolymer is a copolymer represented by the following general formula (I).
In the general formula (I), R ¹ represents hydrogen or a methyl group, R ² represents an alkoxycarbonyl, an optionally substituted aryl group (provided that the substituent is not included in the self-condensing group) of at least R ³ represents an alkyl group, an alkyl group that may be substituted (provided that the substituent does not include a self-condensable group), an aryl group, or an aryl group that may be substituted (provided that the substituent The substituent does not include a self-condensable group.
Moreover, x, y, and z represent the mass composition ratio of a repeating unit, and are x: y: z = 15-30: 20-60: 25-50, and x + y + z = 100. The photosensitive solder resist composition according to claim 3, wherein the (meth) acrylamide copolymer is a copolymer represented by the following general formula (II).
In the general formula (II), R ¹ represents hydrogen or a methyl group, R ² represents an alkoxycarbonyl, an optionally substituted aryl group (provided that the substituent is not included in the self-condensing group) of at least R ³ represents an alkyl group, an optionally substituted alkyl group (however, the substituent does not include a self-condensable group), an aryl group, or an optionally substituted aryl group (provided that the substituted R ⁴ represents an alkyl group, an optionally substituted alkyl group (however, the substituent does not include a self-condensable group), an aryl group, or a substituted group. Represents an aryl group (wherein the substituent does not include a self-condensable group), and R ⁵ represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group.
^{Also, x, y} 1, y ² and z represent weight compositional ratio of the repeating ^{units, x: y 1: y 2} : z = 15~30: 0~60: 0~60: a 25 to 50, y ¹ + ^y 2 = ^20~60, an ^{x + y 1 + y 2 +} z = 100.   The photosensitive solder resist composition according to any one of claims 1 to 4, wherein the thermal crosslinking agent is one of an epoxy resin and a polyfunctional oxetane compound.   The photosensitive solder-resist composition in any one of Claim 1 to 5 containing an inorganic filler.   A photosensitive solder resist comprising: a support; and a photosensitive solder resist layer obtained by laminating the photosensitive solder resist composition according to any one of claims 1 to 6 on the support. Film.   8. The photosensitive solder resist film according to claim 7, further comprising a protective film on the photosensitive solder resist layer. The photosensitive solder resist film according to claim 7, wherein the photosensitive solder resist layer has a thickness of 3 to 100 μm.   A photosensitive solder resist composition according to any one of claims 1 to 6 is applied to the surface of a substrate and dried to form a photosensitive solder resist layer laminate, which is then exposed and developed. A permanent pattern forming method.   10. A method for forming a permanent pattern, comprising: transferring a photosensitive solder resist layer in the photosensitive solder resist film according to any one of claims 7 to 9 to a surface of a substrate; and exposing and developing the photosensitive solder resist layer.   The permanent pattern forming method according to claim 10, wherein the substrate is a printed wiring board on which wiring has been formed.   The exposure is performed using a light irradiation unit that irradiates light and a light modulation unit that modulates light emitted from the light irradiation unit based on pattern information to be formed. A permanent pattern forming method.   The light modulation means further comprises a pattern signal generation means for generating a control signal based on the pattern information to be formed, and the light emitted from the light irradiation means corresponds to the control signal generated by the pattern signal generation means The method for forming a permanent pattern according to claim 13, wherein the permanent pattern is modulated.   The light modulation means has n picture element parts, and pattern information to form any less than n picture element parts continuously arranged from the n picture element parts. The permanent pattern forming method according to claim 13, wherein the permanent pattern forming method can be controlled accordingly.   The exposure is performed through a microlens array in which microlenses having aspherical surfaces capable of correcting aberrations due to distortion of the exit surface of the picture element portion in the light modulation means after the light is modulated by the light modulation means. The permanent pattern formation method according to any one of 13 to 15.   The permanent pattern forming method according to claim 16, wherein the aspherical surface is a toric surface.   The permanent pattern forming method according to claim 10, wherein after the development, the photosensitive solder resist layer is cured.   The permanent pattern forming method according to claim 18, wherein the curing process is at least one of a whole surface exposure process and a whole surface heat treatment performed at 120 to 200 ° C. 19.   A permanent pattern formed by the permanent pattern forming method according to claim 10. The permanent pattern according to claim 20, wherein the permanent pattern is at least one of a protective film, an interlayer insulating film, and a solder resist pattern.