CN101116035A - Photosensitive composition, method for forming pattern, and permanent pattern - Google Patents

Abstract

Disclosed is a photosensitive composition having excellent developability, soldering heat resistance, fracture resistance and pressure cooker resistance which is preferably used for manufacturing flexible printed circuit boards. The cured coating film of such a photosensitive composition is significantly improved in flexibility. Also disclosed are a method for forming a pattern and a permanent pattern. The photosensitive composition contains at least a polyurethane resin (A) having a carboxyl group, a polymerizable compound (B), a photopolymerization initiator (C) and a thermal crosslinking agent (D). The polyurethane resin (A) having a carboxyl group is preferably obtained by reacting a diisocyanate compound represented by the constitutional formula (I) below with a diol compound represented by the constitutional formula (II) or the constitutional formula (III) below.

Description

Photosensitive composition, pattern forming method and permanent pattern

Technical Field

The present invention relates to a photosensitive composition which is excellent in developability, solder heat resistance, folding resistance and moisture resistance, has a cured coating film with greatly improved flexibility, and is suitable for the production of a flexible printed wiring board, a pattern forming method and a permanent pattern.

Background

In recent years, solder resists in various printed wiring boards have been transferred from thermosetting liquid resist resins by screen printing to dilute alkali developing liquid photoresist inks. For example, patent document 1 proposes a solder resist ink composition containing a photocurable resin obtained by reacting a saturated or unsaturated polybasic acid anhydride with a reaction product of a novolak-type epoxy compound and an unsaturated monocarboxylic acid, a photopolymerization initiator, a diluent, and an epoxy compound having 2 or more epoxy groups.

However, in this case, the solder resist ink composition based on the novolac epoxy resin has a drawback that although it is structurally excellent in heat resistance: the cured film is hard and brittle, and adhesion between the coating film and the substrate is deteriorated. Therefore, the use of the solder resist ink composition is limited to rigid substrates such as flexible glass epoxy substrates that do not require a cured coating.

However, in recent years, use of thin and flexible circuit boards (flexible circuit boards) has been increasing in order to simplify processing steps, reduce the size of substrates, increase the density of substrates, and the like, and solder resist ink compositions having flexibility have been demanded. In order to satisfy this requirement, a solder resist ink composition having flexibility has been proposed many times. For example, a solder resist ink composition containing a bisphenol a epoxy resin, a polycarboxylic acid resin having an unsaturated group which is a reaction product of an unsaturated monocarboxylic acid and succinic anhydride, a photopolymerization initiator, a diluent, and a curing agent has been proposed (see patent document 2). However, this proposal has insufficient folding endurance.

In addition, the use of a soluble urethane resin as a photosensitive resin in a dilute alkaline aqueous solution has been studied. For example, there has been proposed a photosensitive resin composition containing a photosensitive resin (a) selected from at least 1 of a photosensitive polyamide resin having a carboxyl group and a photosensitive polyamideimide resin having a carboxyl group, an epoxy resin (B), and a photopolymerization initiator (C) (see patent document 3).

Further, patent document 4 proposes a photosensitive resin composition containing a photosensitive resin (a) having a carboxyl group and obtained by reacting a saturated or unsaturated polybasic acid anhydride with an ester of an epoxy compound and an unsaturated monocarboxylic acid, a photosensitive resin (B), an elastomer (C), an epoxy curing agent (D), and a photopolymerization initiator (E); the epoxy resin (B) is selected from at least 1 of a photosensitive polyamide resin with carboxyl and a photosensitive polyamide-imide resin with carboxyl.

According to these photosensitive resin compositions, a film having flexibility can be obtained, but the current state of the art is: other properties required for resist ink compositions, such as dilute alkali developability, solder heat resistance, and pressure cooker property, which is an important property for substrate reliability, are not sufficient, and it is desired to provide a resist ink composition for circuit substrates having these properties as quickly as possible.

Patent document 1: japanese examined patent publication (Kokoku) No. 1-54390

Patent document 2: japanese unexamined patent publication Hei 8-134390

Patent document 3: japanese unexamined patent publication Hei 10-246958

Patent document 4: japanese unexamined patent publication Hei 11-288087

Disclosure of Invention

The invention aims to provide a photosensitive composition, a pattern forming method and a permanent pattern, wherein the photosensitive composition has excellent developability, solder heat resistance, folding resistance and pressure cooking resistance (1250324841247112516984, 124638412459).

The means for solving the above problems are as follows. That is to say that the temperature of the molten steel,

[ 1] A photosensitive composition characterized by containing at least (A) a polyurethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent.

<2> the photosensitive composition as stated in <1>, wherein (A) the urethane resin having a carboxyl group is formed by reacting a diisocyanate compound represented by the following structural formula (I) with a diol compound represented by any one of the following structural formulae (II) and (III).

[ solution 1]

OCN-R ¹ -NCO of the formula (I)

Structural formula (II)

Structural formula (III)

Wherein, in the structural formulas (I) to (III), R ¹ Represents a divalent hydrocarbon group. R is ² Represents a hydrogen atom or a monovalent hydrocarbon group. R is ³ ～R ⁵ Each of which may be the same or different, represents a divalent hydrocarbon group. Ar represents a trivalent aromatic hydrocarbon group. R ¹ ～R ⁵ And Ar may be further substituted with a substituent, R ² 、R ³ 、R ⁴ And R ⁵ May form a ring.

<3> the photosensitive composition according to any one of <1> to <2>, wherein the acid value of the urethane resin having a carboxyl group (A) is 80 to 300mgKOH/g.

<4> the photosensitive composition according to any one of <1> to <3>, wherein the thermal crosslinking agent (D) is at least one selected from the group consisting of an epoxy resin compound, an oxetane compound, a polyisocyanate compound, a compound obtained by reacting a blocking agent with a polyisocyanate compound, and a melamine derivative.

<5> the photosensitive composition according to any one of the above <1> to <4>, which is used for manufacturing a flexible printed circuit board.

<6> a pattern forming method, characterized in that the photosensitive composition of any one of <1> to <5> is applied on the surface of a substrate, dried to form a photosensitive layer, and then exposed and developed.

<7> the pattern forming method according to <6>, wherein the photosensitive layer is optically modulated by an optical modulation device having n number of pixel portions for receiving and emitting light from an optical irradiation device, and then exposed to light by a microlens array having microlenses arranged therein, each microlens having an aspherical surface capable of correcting aberration caused by deflection of an emission surface in the pixel portion.

<8> the pattern forming method according to <6>, wherein the photosensitive layer is optically modulated by an optical modulation device having n number of line sections for receiving and emitting light from an optical irradiation device, and then exposed by light passing through a microlens array in which microlenses having a lens opening shape for preventing light from the peripheral portion of the line section from entering are arranged.

<9> the pattern forming method as stated in the aforementioned <8>, wherein the microlens has an aspherical surface which can correct aberration caused by a skew of the exit surface in the sketch portion.

<10> the pattern forming method according to any one of the above <7> to <9>, wherein the aspheric surface is a toric (toric) surface.

<11> the pattern forming method as stated in the aforementioned <8>, wherein the microlens opening shape is a circular shape.

<12> the pattern forming method according to any one of <8> to <11>, wherein the lens opening shape is normalized by providing a light shielding portion on the lens surface.

<13> the pattern forming method according to any one of <7> to <12>, wherein the light modulation device can control any less than n of the plurality of line segments arranged in series based on the pattern information.

<14> the pattern forming method according to any one of <7> to <13>, wherein the light modulation device is a spatial light modulation element.

<15> the pattern forming method as stated in the aforementioned <14>, wherein the spatial light modulation element is a Digital Micromirror Device (DMD).

<16> the pattern forming method according to any one of <7> to <15>, wherein the light irradiation device includes a plurality of lasers, a multimode optical fiber, and a condensing optical system for condensing and coupling laser beams irradiated from the plurality of types of laser beams to the multimode optical fiber.

<17> the pattern forming method of <16>, wherein the wavelength of the laser light is 395 to 415nm.

<18> a permanent pattern formed by the pattern forming method of any one of <6> to <17 >.

The photosensitive composition of the present invention contains at least (a) a urethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent. The urethane resin (a) having a carboxyl group is formed by reacting a diisocyanate compound having a specific structure with a diol compound having a specific structure. As a result, a photosensitive composition excellent in dilute alkali developability is obtained, and a cured film thereof has excellent flexibility, adhesion, solder heat resistance, folding resistance and retort resistance, and is suitable for the production of a flexible printed wiring board.

The present invention solves the problems of the prior art, and provides a photosensitive composition, a pattern forming method and a permanent pattern, wherein the photosensitive composition has excellent developability, solder heat resistance, folding resistance and retort resistance, the cured coating film has greatly improved flexibility, and the photosensitive composition is suitable for manufacturing a flexible printed circuit board.

Drawings

Fig. 1 is an example of a partially enlarged view showing a configuration of a Digital Micromirror Device (DMD).

Fig. 2A is an example of an explanatory diagram for explaining the operation of the DMD.

Fig. 2B is an example of an explanatory diagram for explaining the operation of the DMD similar to fig. 2A.

Fig. 3A is an example of a plan view showing the arrangement of the exposure light beams and the scanning lines in comparison between the case where the DMD is not arranged in a tilted state and the case where the DMD is arranged in a tilted state.

Fig. 3B is an example of a plan view showing the arrangement of the exposure light beams and the scanning lines in comparison between the case where the DMD is not arranged in an inclined manner and the case where the DMD is arranged in an inclined manner, as in fig. 3A.

Fig. 4A is an example of a diagram showing an example of a use area of the DMD.

Fig. 4B is an example of a diagram showing an example of a use area of the DMD similar to fig. 4A.

Fig. 5 is an example of a plan view for explaining an exposure method of exposing the pattern forming material by 1 scan by the scanner.

Fig. 6A is an example of a plan view for explaining an exposure method of exposing a pattern forming material by performing scanning a plurality of times by a scanner.

Fig. 6B is an example of a plan view for explaining an exposure method of exposing the pattern forming material to light by performing scanning a plurality of times by the same scanner as that of fig. 6A.

Fig. 7 is an example of a schematic perspective view showing an external appearance of an example of the pattern forming apparatus.

Fig. 8 is an example of a schematic perspective view showing a configuration of a scanner of the pattern forming apparatus.

Fig. 9A is an example of a plan view showing an exposed region formed in the pattern forming material.

Fig. 9B is an example of an arrangement of exposure regions by the respective exposure heads.

Fig. 10 is an example of a perspective view showing a schematic configuration of an exposure head including an optical modulator.

Fig. 11 is an example of a cross-sectional view in the sub-scanning direction along the optical axis of the exposure head shown in fig. 10.

Fig. 12 shows an example of a controller for controlling the DMD based on pattern information.

Fig. 13A is an example of a cross-sectional view along the optical axis of another configuration of the exposure head with a different coupling optical system.

Fig. 13B is a top view showing an example of an optical image projected on an exposed surface without using a microlens array or the like.

Fig. 13C is a top view showing an example of an optical image projected on an exposed surface when a microlens array or the like is used.

Fig. 14 is an example of a diagram showing the deflection of the reflection surface of the micromirror constituting the DMD by contour lines.

Fig. 15A is an example of a diagram showing the deflection of the reflective surface of the micromirror in two diagonal directions of the mirror.

Fig. 15B is an example of a view showing the deflection of the reflection surface of the micro mirror in the two diagonal directions of the mirror, which is the same as fig. 15A.

Fig. 16A is an example of a front view of a microlens array used in the patterning device.

Fig. 16B is an example of a side view of a microlens array used in the patterning device.

Fig. 17A is an example of a front view of microlenses constituting a microlens array.

Fig. 17B is an example of a side view of microlenses constituting the microlens array.

Fig. 18A is an example of a schematic diagram showing a condensed state by the microlens in one cross section.

Fig. 18B is an example of a schematic view showing a condensed light state by the microlenses in one cross section.

Fig. 19A is an example of a graph showing a result of simulating the beam diameter in the vicinity of the condensing position of the microlens of the present invention.

Fig. 19B is an example of a graph showing the same simulation result as fig. 19B at other positions.

Fig. 19C is an example of a graph showing the same simulation result as in fig. 19A at other positions.

Fig. 19D is an example of a graph showing the same simulation result as in fig. 19A at other positions.

Fig. 20A is an example of a graph showing a result of simulating a beam diameter near a condensing position of a microlens in a conventional pattern forming method.

Fig. 20B is an example of a graph showing the same simulation result as fig. 20A for other positions.

Fig. 20C is an example of a graph showing the same simulation result as in fig. 20A for other positions.

Fig. 20D is an example of a graph showing the same simulation result as fig. 20A for other positions.

Fig. 21 is an example of a plan view showing another configuration of the combined-wave laser light source.

Fig. 22A is an example of a front view of microlenses constituting a microlens array.

Fig. 22B is an example of a side view of microlenses constituting the microlens array.

Fig. 23A is a schematic diagram showing an example of a condensed state formed by the microlenses of fig. 22A and B in one cross section.

Fig. 23B is a schematic diagram showing an example of a cross section different from the example of fig. 23A.

Fig. 24A is an example of an explanatory view of a concept of correction by the light amount distribution correcting optical system.

Fig. 24B is an explanatory diagram illustrating an example of a concept of correction by the light amount distribution correcting optical system.

Fig. 24C is an example of an explanatory view of a concept of correction by the light quantity distribution correction optical system.

Fig. 25 is an example of a diagram showing a light amount distribution when the light irradiation device has a gaussian distribution and the light amount distribution is not corrected.

Fig. 26 is an example of a diagram showing a light quantity distribution corrected by the light quantity distribution correction optical system.

Fig. 27A (a) is a perspective view showing a configuration of a fiber array light source, fig. 27A (B) is an example of a partially enlarged view of (a), and fig. 27A (C) and (D) are examples of plan views showing an arrangement of light emitting points in a laser emitting portion.

Fig. 27B is an example of a front view showing an arrangement of light emitting points in a laser emitting portion of the fiber array light source.

Fig. 28 is an example of a configuration of a multimode optical fiber.

Fig. 29 is a plan view showing an example of the configuration of the light source of the multiplex laser.

Fig. 30 is an example of a plan view showing the structure of the laser module.

Fig. 31 is a side view showing an example of the configuration of the laser module shown in fig. 30.

Fig. 32 is a partial side view showing the structure of the laser module shown in fig. 30.

Fig. 33 is a perspective view showing an example of the configuration of the laser array.

Fig. 34A is an example of a perspective view showing a configuration of a multi-cavity laser.

Fig. 34B is an example of a perspective view of a multi-cavity laser array in which the multi-cavity laser beams shown in fig. 34A are arranged in an array.

Fig. 35 is an example of a plan view showing another configuration of the combined-wave laser light source.

Fig. 36A is an example of a plan view showing another configuration of the combined wave laser light source.

Fig. 36B is an example of a cross-sectional view along the optical axis of fig. 36A.

Fig. 37A is an example of a cross-sectional view taken along an optical axis showing a difference between a depth of focus in a conventional exposure apparatus and a depth of focus formed by the pattern forming method (pattern forming apparatus) of the present invention.

Fig. 37B is an example of a cross-sectional view taken along an optical axis showing the difference between the depth of focus in a conventional exposure apparatus and the depth of focus formed by the pattern forming method (pattern forming apparatus) of the present invention.

Fig. 38A is a front view showing another example of microlenses constituting a microarray.

Fig. 38B is a side view showing another example of the microlens constituting the microarray.

Fig. 39A is a front view showing an example of a microlens constituting a microarray.

Fig. 39B is a side view showing an example of a microlens constituting a microarray.

Fig. 40 is a diagram showing an example of the shape of a spherical lens.

Fig. 41 shows another example of the lens surface shape.

Fig. 42 is a perspective view showing another example of the microlens array.

Fig. 43 is a plan view showing another example of the microlens array.

Fig. 44 is a plan view showing another example of the microlens array.

Fig. 45A is a longitudinal sectional view showing another example of the entire microlens array.

Fig. 45B is a longitudinal sectional view showing another example of the entire microlens array.

Fig. 45C is a longitudinal sectional view showing another example of the entire microlens array.

Detailed Description

(photosensitive composition)

The photosensitive composition of the present invention contains at least (a) a urethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent, and further contains other components as required.

[ (A) polyurethane resin having carboxyl group ]

The urethane resin having a carboxyl group is not particularly limited and may be appropriately selected according to the purpose. The urethane resin is preferably formed by reacting a diisocyanate compound represented by the following structural formula (I) with a diol compound represented by any one of the following structural formulae (II) and (III).

[ solution 3]

OCN-R ¹ -NCO structural formula (I)

Structural formula (II)

Structural formula (III)

In the above structural formula (I), R ¹ Represents a divalent hydrocarbon group, for example, a divalent aliphatic hydrocarbon group or a divalent aromatic hydrocarbon group. The divalent aliphatic hydrocarbon group is preferably an alkylene group, and examples thereof include: ethylene, propylene, butylene, pentylene, hexylene, and the like. The divalent aromatic hydrocarbon group is preferably an arylene group obtained by removing one hydrogen atom from an aryl group, for example, a phenylene group or the like. In addition, in R ¹ Other functions not reacting with isocyanate groupsThe group may have, for example, an ester group, urethane group, amide group, ureide group, or the like. These groups may be further substituted with a substituent.

Examples of the aforementioned substituents are: hydroxyl, halogen atom, nitro, carboxyl, cyano, alkyl, aryl, heterocyclic group, and the like.

In the above structural formula (II), R ² Represents a hydrogen atom or a monovalent hydrocarbon group. The monovalent hydrocarbon group is exemplified by any of alkyl groups, aralkyl groups, aryl groups, alkoxy groups, and aryloxy groups, which may be further substituted with a substituent.

The alkyl group is preferably an alkyl group having 1 to 8 carbon atoms, and examples thereof include: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-hexyl, isohexyl, n-heptyl, n-octyl, isooctyl and the like.

The aforementioned aralkyl group is not particularly limited and may be appropriately selected according to the purpose, and for example, there are: benzyl, phenethyl, phenylpropyl, and the like.

The aryl group is not particularly limited and may be appropriately selected according to the purpose, and is preferably an aryl group having 6 to 15 carbon atoms, and examples thereof include: phenyl, tolyl, xylyl, biphenyl, naphthyl, anthryl, phenanthryl, and the like.

The alkoxy group is preferably an alkoxy group having 1 to 10 carbon atoms, and examples thereof include: methoxy, ethoxy, propoxy, butoxy, and the like.

In the above structural formulae (II) and (III), R ³ ～R ⁵ Each of which may be the same or different, represents a divalent hydrocarbon group. The divalent hydrocarbon group may be the same as that of R1, and is preferably an alkylene group having 1 to 20 carbon atoms or an arylene group having 6 to 15 carbon atoms.

Ar represents a trivalent aromatic hydrocarbon group, and examples thereof include: an arylene group obtained by removing 2 hydrogen atoms from an aryl group.

R ¹ ～R ⁵ And Ar may be further substituted with a substituent, R ² 、R ³ 、R ⁴ And R ⁵ May form a ring. The ring being, for exampleComprises the following steps: aromatic rings, aliphatic rings, heterocyclic rings, and the like.

Specific examples of the diisocyanate compound represented by the structural formula (I) include: aromatic diisocyanate compounds such as 2, 4-tolylene diisocyanate, dimer of 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate, p-xylylene diisocyanate, methylxylylene diisocyanate, 4' -diphenylmethane diisocyanate, 1, 5-naphthylene diisocyanate, 3' -dimethyl-biphenyl-4, 4' -diisocyanate and the like; aliphatic diisocyanate compounds such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lycine diisocyanate, dimer acid diisocyanate, and the like; alicyclic diisocyanate compounds such as isophorone diisocyanate, 4' -methylene bis (cyclohexyl isocyanate), methylcyclohexane-2, 4 (or 2, 6) diisocyanate, and 1,3- (methyl isocyanate) cyclohexane; and diisocyanate compounds which are reaction products of a diisocyanate compound and a diol compound such as an adduct of 1,3-butanediol and 2 moles of toluene diisocyanate. These substances may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The diol compound having a carboxyl group represented by the aforementioned structural formula (II) or the aforementioned structural formula (III) is, for example: 3, 5-dihydroxybenzoic acid, 2-bis (hydroxymethyl) propionic acid, 2-bis (hydroxyethyl) propionic acid, 2-bis (3-hydroxypropyl) propionic acid, 2-bis (hydroxymethyl) acetic acid, bis- (4-hydroxyphenyl) acetic acid, 4-bis- (4-hydroxyphenyl) pentanoic acid, tartaric acid, and the like. These substances may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The urethane resin may be formed from 2 or more kinds of the diisocyanate compound represented by the structural formula (I) and the diol compound having a carboxyl group represented by the structural formula (II) or (III).

In addition, a diol compound which does not have a carboxyl group and may have a substituent which does not react with another isocyanate compound may be used together within a range in which the alkali developability is not lowered. Examples of the diol compound include: ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, neopentyl glycol, 1, 3-butanediol, 1, 6-hexanediol, 2-butene-1, 4-diol, 2, 4-trimethyl-1, 3-pentanediol, 1, 4-di- β -hydroxyethoxycyclohexane, cyclohexanedimethanol, tricyclodecanedimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, an ethylene oxide adduct of bisphenol A, a propylene oxide adduct of bisphenol A, an ethylene oxide adduct of bisphenol F, a propylene oxide adduct of bisphenol F, an ethylene oxide adduct of hydrogenated bisphenol A, a propylene oxide adduct of hydrogenated bisphenol A, hydroquinone dihydroxyethyl ether, p-xylylene alcohol, dihydroxyethyl sulfone, bis- (2-hydroxyethyl) 2, 4-toluenedicarbamate, 2, 4-toluenedi- (2-hydroxyethyl urea), bis- (2-hydroxyethyl) m-xylylene carbamate, bis- (2-hydroxyethyl) phthalate, and the like. These substances may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The aforementioned polyurethane resin can be synthesized by the following operations: the diisocyanate compound and the diol compound are added to an aprotic solvent in accordance with their respective reactivities with a known catalyst, and heated.

The molar ratio of the diisocyanate compound to the diol compound (diisocyanate compound: diol compound) is preferably 0.8: 1 to 1.2: 1. When isocyanate groups remain at the ends of the polyurethane resin, the polyurethane resin is finally synthesized without remaining isocyanate groups by treatment with alcohols, amines, or the like.

The acid value of the polyurethane resin of the component (A) is preferably 80 to 300mgKOH/g, more preferably 80 to 180mgKOH/g, still more preferably 90 to 170mgKOH/g, and particularly preferably 100 to 160mgKOH/g. When the acid value is less than 80mgKOH/g, the obtained photosensitive composition may not exhibit excellent alkali developability, and when it exceeds 300mgKOH/g, the shape of the pattern formed from the obtained photosensitive composition may be deteriorated and high resolution may not be obtained.

The acid value is measured by the following method: the acid value can be calculated from the amount of neutralization by dissolving a certain amount of the urethane carboxylic acid in a solvent such as methoxypropanol and titrating the solution with an aqueous potassium hydroxide solution of known titer.

The weight average molecular weight (Mw) of the polyurethane resin having a carboxyl group is preferably 1000 or more, and more preferably 5000 to 10 ten thousand.

The content of the urethane resin having a carboxyl group is preferably 50 to 99.5% by mass, and more preferably 50 to 95% by mass, based on the photosensitive composition. When the content of the urethane resin is less than 50% by mass, the object and effect of the present invention may not be achieved, and when it is too large, the amount of the polymerizable compound present is relatively reduced, so that the alkali developer resistance of the exposed portion, the mechanical strength of the cured film, and the solder heat resistance may be deteriorated.

In addition to the urethane resin, it is preferable that another resin is added to the photosensitive composition of the present invention as needed, and the content thereof is 50 mass% or less with respect to the urethane resin. Examples of the other resins include: polyamide resins, epoxy resins, polyacetal resins, acrylic resins, methacrylic resins, polystyrene resins, novolac-type phenol resins, and the like.

[ (B) polymerizable Compound ]

The polymerizable compound is not particularly limited and may be appropriately selected according to the purpose, and is preferably a compound having at least 1, preferably 2 or more groups capable of addition polymerization in a molecule and having a boiling point of 100 ℃ or higher under normal pressure, and examples thereof include at least 1 selected from monomers having a (meth) propenyl group.

The aforementioned monomer having a (meth) acryl group is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include: monofunctional acrylates and monofunctional methacrylates such as polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) acrylate, and the like; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane diacrylate, neopentyl glycol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyl hydroxypropyl) ether, triisocyanato tri (acryloyl hydroxyethyl) ester, tricyanocyanato tri (acryloyl hydroxyethyl) ester, glycerol tri (meth) acrylate, trimethylolpropane, glycerol, and polyfunctional alcohols such as bisphenol, which are subjected to addition reaction with ethylene oxide and propylene oxide and then subjected to (meth) acrylation, urethane acrylates described in Japanese patent publication Nos. 48-41708, 50-6034, 51-37193 and the like; polyester acrylates described in Japanese patent laid-open Nos. 48-64183, 49-43191 and 52-30490; and polyfunctional acrylates or methacrylates such as epoxy acrylates as a reaction product of an epoxy resin and (meth) acrylic acid. Among them, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta (meth) acrylate are particularly preferable.

The solid content of the polymerizable compound in the solid content of the photosensitive composition is preferably 5 to 50% by mass, more preferably 10 to 40% by mass. When the solid content is less than 5% by mass, problems such as deterioration of developability and reduction of exposure sensitivity may occur, and when it exceeds 50% by mass, the adhesiveness of the photosensitive layer may be excessively strong, which is not preferable.

[ (C) polymerization initiator ]

The photopolymerization initiator is not particularly limited as long as it has a capability of initiating polymerization of the polymerizable compound, and may be appropriately selected from known photopolymerization initiators, and for example, a polymerization initiator having photosensitivity to visible light from an ultraviolet region is preferable, and may be an initiator which generates active radicals by acting on a sensitizer formed by photoexcitation, or may be an initiator which initiates cationic polymerization depending on the kind of a monomer.

In addition, the photopolymerization initiator is preferably: contains at least 1 component having a molecular absorption coefficient of at least about 50 in the range of about 300 to 800nm, more preferably 330 to 500 nm.

Examples of the photopolymerization initiator include: halogenated hydrocarbon derivatives (for example, halogenated hydrocarbon derivatives having a triazine skeleton, halogenated hydrocarbon derivatives having an oxadiazole skeleton, etc.), phosphine oxides, hexaarylbiimidazole, oxime derivatives, organic peroxides, sulfides, ketonates, aromatic onium salts, ketoxime ethers, etc.

Examples of the halogenated hydrocarbon compound having a triazine skeleton include: compounds described in bull. Chem. Soc. Japan,42, 2924 (1969), compounds described in british patent No. 1388492, compounds described in japanese patent application publication No. 53-133428, compounds described in german patent No. 3337024, j.org.chem. according to f.c. schaefer et al; 29. 1527 (1964), a compound described in Japanese patent laid-open publication No. 62-58241, a compound described in Japanese patent laid-open publication No. 5-281728, a compound described in Japanese patent laid-open publication No. 5-34920, a compound described in the specification of U.S. Pat. No. 4212976, and the like.

Examples of the compounds described in Bull. Chem. Soc. Japan,42, 2924 (1969) by Ruhling et al include: 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-methoxybenzyl) -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- (α, α, β -trichloroethyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, and the like.

Examples of the compounds described in the specification of British patent No. 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-amino-6-trichloromethyl-1, 3, 5-triazine, and the like.

Examples of the compounds described in the above-mentioned Japanese patent laid-open No. 53-133428 include: 2- (4-methoxy-naphtho-1-acyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4-ethoxy-naphthalene-1-acyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- [4- (2-ethoxyethyl) -naphthalene-1-acyl ] -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4, 7-dimethoxy-naphthalene-1-acyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, and 2- (acenaphthylene-5-acyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, and the like.

Examples of the compounds described in the specification of the aforementioned German patent No. 3337024 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-naphthylvinyienylidene) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2-chlorostyrylphenyl-4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4-thiophene-2-vinyiidene) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4-thiophene-3-vinyiidene) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4-furan-2-vinyiidene) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, and 2- (4-benzofuran-2-vinyiidene) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, etc.

Chem, j.org.chem. by f.c. schaefer et al, supra; 29. the compound described in 1 (1964) is, for example: 2-methyl-4, 6-bis (tribromomethyl) -1,3, 5-triazine, 2,4, 6-tris (dibromomethyl) -1,3, 5-triazine, 2-amino-4-methyl-6-tris (bromomethyl) -1,3, 5-triazine, and 2-methoxy-4-methyl-6-trichloromethyl-1, 3, 5-triazine, and the like.

Examples of the compounds described in the above-mentioned Japanese patent application laid-open No. 62-58241 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-isopropylphenylethynyl) phenyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, 2- (4- (4-ethylphenylethynyl) phenyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, and the like.

Examples of the compounds 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-triazine, 2- (2, 6-dibromophenyl) -4, 6-bis (trichloromethyl) -1,3, 5-triazine, and the like.

Examples of the compounds described in the above-mentioned Japanese patent application laid-open No. Hei 5-34920 include: 2,4-bis (trichloromethyl) -6- [4- (N, N-diethoxycarbonylmethylamino) -3-bromophenyl ] -1,3,5-triazine, trihalomethyl-s-triazine compound described in the specification of U.S. Pat. No. 4239850, and 2,4,6-tris (trichloromethyl) -s-triazine, 2- (4-chlorophenyl) -4,6-bis (tribromomethyl) -s-triazine and the like.

Examples of the compounds described in the specification of the aforementioned U.S. Pat. No. 4212976 include: compounds having an oxadiazole skeleton (e.g., 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-tribromomethyl-5- (1-naphthyl) -1,3, 4-oxadiazole, 2-trichloromethyl-5- (4-n-butoxystyryl) -1,3, 4-tribromomethyl-oxadiazole, etc.) and the like can be used as a pharmaceutically acceptable carrier.

Examples of oxime derivatives suitable for use in the present invention include: 3-benzoyloxyiminobutane-2-one, 3-acetoxyiminobutane-2-one, 3-propionyloxyiminobutane-2-one, 2-acetoxyiminobutane-3-one, 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, 3- (4-toluenesulfonyloxy) iminobutane-2-one, and 2-ethoxycarbonylhydroxyimino-1-phenylpropan-1-one.

Examples of the photopolymerization initiators other than the above include: acridine derivatives (e.g., 9-phenylazeridine, 1, 7-bis (9, 9' -acridinyl) heptane, etc.); n-phenylglycine and the like; polyhalogenated compounds (e.g., carbon tetrabromide, phenyl tribromomethylsulfone, phenyl trichloroketone, etc.); coumarins (e.g., compounds described in JP-A-5-19475, JP-A-7-271028, JP-A-2002-363206, JP-A-2002-363207, JP-A-2002-3203202002-3207, JP-A-3208, JP-A-363209, and JP-A-3209) such as 3- (2-benzoyl) -7- (1-pyrrolidinyl) coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-dimethylaminobenzoyl) -7-diethylaminocoumarin, 3 '-carbonylbis (5, 7-di-n-propoxycoumarin), 3' -carbonylbis (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-acylcoumarin, JP-2002-363207-2002-363208, JP-2002-3209, and the like); amines (e.g., ethyl 4-dimethylaminobenzoate, N-butyl 4-dimethylaminobenzoate, phenethyl 4-dimethylaminobenzoate, 2-phthalimide ethyl 4-dimethylaminobenzoate), 2-methacryloxyethyl 4-dimethylaminobenzoate, pentamethylenebis (4-dimethylaminobenzoate), phenethyl ester of 3-dimethylaminobenzoate, pentamethylene ester, 4-dimethylaminobenzaldehyde, 2-chloro-4-dimethylaminobenzaldehyde, 4-dimethylaminobenzylalcohol, ethyl (4-dimethylaminobenzoyl) acetate, 4-piperidineacetophenone, 4-dimethylaminobenzoic acid, N-dimethyl-4-toluidine, N-diethyl-3-ethoxyaniline, tribenzylamine, dibenzylaniline, N-methyl-N-phenylbenzylamine, 4-bromo-N, N-dimethylaniline, trilaurylamine, aminofluoralkanes (ODB, ODB II, etc.), violactone, crystal violet, etc.), phosphoryl violet, etc.), leuco oxogroups (for example: bis (2, 4, 6-trimethylbenzoyl) -phenylphosphine oxide, bis (2, 6-dimethoxybenzoyl) -2, 4-trimethyl-pentylphenylphosphine oxide, lucirin TPO, etc.), metallocene (e.g.: bis (. Eta.5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrole-1-yl) -phenyl) titanium,. Eta.5-cyclopentadienyl-. Eta.6-cumenyl-iron (1 +) -hexafluorophosphate (1-), etc.), the compounds described in Japanese patent laid-open publication No. 53-133428, japanese patent publication No. 57-1819, japanese patent publication No. 57-6096 and U.S. patent No. 1543655, etc.

Examples of the ketone compound include: benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methoxybenzophenone, 2-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, 2-ethoxycarbonylbenzophenone, benzophenone tetracarboxylic acid or its tetramethyl ester, 4' -bis (dialkylamino) benzophenone (for example: 4,4' -bis (dimethylamino) benzophenone, 4' -bis (dicyclohexylamino) benzophenone, 4' -bis (diethylamino) benzophenone, 4' -bis (dihydroxyethylamino) benzophenone, 4-methoxy-4 ' -dimethylaminobenzophenone, 4' -dimethoxybenzophenone, 4-dimethylaminobenzophenone, 4-dimethylaminoacetophenone, dibenzoyl, anthraquinone, 2-tert-butylanthraquinone, 2-methylanthraquinone, phenanthrenequinone, xanthone, thioxanthone, 2-chloro-thioxanthone, 2, 4-diethylthioxanthone, fluorenone, 2-benzyl-dimethylamino-1- (4-morpholinophenyl) -1-butanone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinyl-1-propanone, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl ] propanol oligomer, and mixtures thereof, benzine, benzine ethers (e.g., benzine methyl ether, benzine ethyl ether, benzine propyl ether, benzine isopropyl ether, benzine phenyl ether, benzyl dimethyl ketal), acridone, chloroacridone, N-methylacridone, N-butylacridone, N-butyl-chloroacridone, etc.

In addition, a sensitizer may be added to the photopolymerization initiator in order to adjust the photosensitivity or the photosensitive wavelength of exposure in the photosensitive layer described later.

The sensitizer may be appropriately selected from visible light, ultraviolet light, visible light laser, and the like, which are light irradiation devices to be described later.

The sensitizer is excited by an active energy beam and interacts (for example, energy transfer, electron transfer, etc.) with another substance (for example, a radical generator, an acid generator, etc.) to generate a useful group such as a radical or an acid.

The sensitizer is not particularly limited, and may be appropriately selected from known sensitizers, and examples thereof include: known polynuclear aromatics (e.g., pyrene, perillene, triphenylene), xanthenes (e.g., fluorescein, eosin, erythromycin, rhodamine B, rose bengal), cyanines (e.g., indocyanine, cyanine), cyanine compounds (e.g., cyanine), thiazines (e.g., thionine, methylene blue, toluidine blue), acridines (e.g., acridine orange, flavine, acridine yellow); anthraquinones (e.g., anthraquinone), \124635012512454\ 1252; \\124735012512522125542facridones (e.g., acridone, chloroacridone, N-methylacridone, N-butylacridone, N-butyl-chloroacridone, etc.), coumarins (e.g., 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 '-carbonylbis (5, 7-di-N-propoxycarbonyl), 3' -carbonylbis (7-diethylaminocoumarin), 3-benzoyl-7-methoxycoumarin, 3- (2-furoyl) -7-diethylaminocoumarin, 3- (4-diethylaminocinnamoyl) -7-diethylaminocoumarin, 7-methoxy-3- (3-pyridinecarbonyl) 3- (3-dipropionylcoumarin) coumarin, no. 3-dipropionylcoumarin No. 3205-0285, no. 7-2715, no. 7-2710285, no. 3-2710285 And coumarin compounds described in Japanese patent application laid-open Nos. 2002-363207, 2002-363208, and 2002-363209.

Examples of the combination of the photopolymerization initiator and the sensitizer include: JP-A-2001-305734 discloses combinations of an electron transfer type initiator [ (1) an electron donating initiator and a sensitizing dye, (2) an electron accepting initiator and a sensitizing dye, (3) an electron donating initiator, a sensitizing dye, and an electron accepting initiator (ternary initiation system).

The content of the sensitizer is preferably 0.05 to 30% by mass, more preferably 0.1 to 20% by mass, and particularly preferably 0.2 to 10% by mass, based on the entire components of the photosensitive resin composition. If the content is less than 0.05% by mass, the sensitivity to active energy rays may be reduced, which takes time in the exposure step and reduces productivity, and if it exceeds 30% by mass, the sensitizer may be precipitated from the photosensitive layer during storage.

The photopolymerization initiator may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

As a particularly preferable example of the photopolymerization initiator, a complex photoinitiator which is a combination of the phosphine oxide compound, the α -aminoalkylketone, the halogenated hydrocarbon compound having a triazine skeleton and the amine compound as a sensitizer described later, which can respond to laser light having a wavelength of 405nm, a hexaarylbiimidazole compound, a titanium alkene (124817912494124753131).

The content of the photopolymerization initiator in the photosensitive composition is preferably 0.1 to 30% by mass, more preferably 0.5 to 20% by mass, and particularly preferably 0.5 to 15% by mass.

[ thermal crosslinking agent ]

The thermal crosslinking agent is not particularly limited and may be appropriately selected according to the purpose, and in order to improve the strength of a cured film of the photosensitive layer formed using the photosensitive composition, at least 1 selected from, for example, an epoxy resin compound, an oxetane compound, a polyisocyante compound, a compound obtained by reacting a blocking agent with a polyisocyanate compound, and a melamine derivative may be used within a range not affecting the developability and the like.

Examples of the epoxy resin compounds include, but are not limited to, glycidyl methacrylate resins such as bis-xylenol type or bisphenol type epoxy resins ("YX 4000, 1247212511699, \\\ 124711252488810, and mixtures thereof, and heterocyclic epoxy resins having an isocyanate skeleton and the like (" TEPIC, japanese chemical industries, and the like ". These epoxy resins may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

Examples of the oxetane compound include: polyfunctional oxetanes such as bis [ (3-methyl-3-oxetanylmethoxy) methyl ] ether, 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, acrylic acid (3-methyl-3-oxetanyl) methyl ester, acrylic acid (3-ethyl-3-oxetanyl) methyl ester, methacrylic acid (3-methyl-3-oxetanyl) methyl ester, methacrylic acid (3-ethyl-3-oxetanyl) methyl ester or oligomers or copolymers of these, and further, oxetanyl and novolac resins, curds (1241245989) type bis, 1241241251241251241257112599, and others, and also, alicyclic resins having a hydroxyl group 12471125 (r) and others.

In order to promote the thermal curing of the epoxy resin compound and the oxetane compound, for example: amine compounds such as dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethylbenzylamine, and 4-methyl-N, N-dimethylbenzylamine; quaternary ammonium salt compounds such as triethylbenzylammonium chloride; blocked isocyanate compounds such as dimethylamine; imidazole derivative bicyclic amidine compounds such as imidazole, 2-methyl-imidazole, 2-ethyl-4-methyl-imidazole, 2-phenyl-imidazole, 4-phenyl-imidazole, 1-cyanoethyl-2-phenyl-imidazole, and 1- (2-cyanoethyl) -2-ethyl-4-methyl-imidazole, and salts thereof; phosphorus compounds such as triphenylphosphine; guanamine compounds such as melamine, guanamine, acetoguanamine, and benzoguanamine; s-triazine derivatives such as 2, 4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2, 4-diamino-S-triazine, 2-vinyl-4, 6-diamino-S-triazine trimeric isocyanate adduct, and 2, 4-diamino-6-methacryloyloxyethyl-S-triazine trimeric isocyanate adduct. These substances can be used alone in 1, also can be used simultaneously more than 2. The curing catalyst for the epoxy resin compound and the oxetane compound is not particularly limited as long as it can accelerate the reaction between these compounds and the carboxyl group, and compounds other than those mentioned above which can accelerate the thermal curing can be used.

In the solid content of the photosensitive composition, the solid content of the epoxy resin, the oxetane compound and the compound capable of promoting the thermosetting of these and the carboxylic acid is usually 0.01 to 15% by mass.

The thermal crosslinking agent may be a polyisocyanate compound derived from an aliphatic, cyclic aliphatic or aromatic-substituted aliphatic compound having at least 2 isocyanate groups, as described in JP-A-5-9407. Specific examples include: 2-functional isocyanates such as 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-isocyanato-phenyl) methane, bis (4-isocyanatocyclohexyl) methane, isophorone diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate; the 2-functional isocyanate and a polyfunctional alcohol such as trimethylolpropane, pentaerythritol, glycerol, etc.; an alkylene oxide adduct of the polyfunctional alcohol and an adduct of the aforementioned 2-functional isocyanate; cyclic trimer such as hexamethylene diisocyanate, hexamethylene-1, 6-diisocyanate and derivatives thereof, and the like.

In order to improve the storage stability of the photosensitive composition of the present invention, a compound obtained by reacting a blocking agent with the isocyanate group of the polyisocyanate or the derivative thereof may be used.

Examples of the isocyanate-based blocking agent include: alcohols such as isopropyl alcohol and tert-butyl alcohol; lactams such as epsilon-caprolactam; phenols such as phenol, cresol, p-tert-butylphenol, p-sec-butylphenol, p-tert-amylphenol, p-octylphenol, and p-nonylphenol; heterocyclic hydroxy compounds such as 3-hydroxypyridine and 8-hydroxyquinoline; and active methylene compounds such as dialkyl malonate, methyl ethyl ketoxime, acetylacetone, alkyl acetoacetate oxime, acetoxime, cyclohexanone oxime, and the like. Further, a compound having at least 1 polymerizable double bond and at least one blocked isocyanate group in the molecule as described in Japanese patent application laid-open No. 6-295060, and the like can be used.

Further, a melamine derivative may be used as the crosslinking agent. Examples of such melamine derivatives are: methylolmelamine, alkylated methylolmelamine (compounds in which methylol groups are etherified with methyl, ethyl, butyl, or the like), and the like. These substances may be used alone in 1 kind, or may be used in combination in 2 or more kinds. Among them, alkylated methylolmelamine is preferable, and hexamethylated methylolmelamine is particularly preferable, in terms of good storage stability and effective improvement of the surface hardness of the photosensitive layer and the film strength of the cured film itself.

In the photosensitive composition solid content, the solid content of the crosslinking agent is preferably 1 to 40% by mass, more preferably 3 to 20% by mass. When the solid content is less than 1% by mass, the film strength of the cured film is not improved, and when it exceeds 40% by mass, the developability is lowered and the exposure sensitivity is lowered in some cases.

[ other ingredients ]

Examples of the other components include: a thermal polymerization inhibitor, a plasticizer, a coloring agent (coloring pigment or dye), a filler pigment, and the like, and an adhesion promoter to the surface of the substrate and other auxiliary agents (for example, conductive particles, a filler, an antifoaming agent, a flame retardant, a leveling agent, a peeling promoter, an antioxidant, a perfume, a surface tension regulator, a chain transfer agent, and the like) may be used together. By appropriately containing these components, properties such as stability, photographic properties, and film physical properties of the desired photosensitive composition can be adjusted.

Thermal polymerization inhibitors

The thermal polymerization inhibitor may be added to prevent thermal polymerization or polymerization with time of the polymerizable compound.

Examples of the thermal polymerization inhibitor include: 4-methoxyphenol, hydroquinone, 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-methylphenol, 2' -methylenebis (4-methyl-6-t-butylphenol), pyridine, nitrobenzene, dinitrobenzene, picric acid, 4-toluidine, methylene blue, a reactant of copper and an organic chelating agent, methyl salicylate and phenothiazine, a nitroso compound, a chelate of a nitroso compound and Al, and the like.

The content of the thermal polymerization inhibitor is preferably 0.001 to 5% by mass, more preferably 0.005 to 2% by mass, and particularly preferably 0.01 to 1% by mass, based on the polymerizable compound. When the content is less than 0.001% by mass, the stability during storage may be lowered, and when it exceeds 5% by mass, the sensitivity to active energy rays may be lowered.

Coloring pigments

The aforementioned coloring pigment is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: victoria pure blue BO (c.i. 42595), sophorae yellow (c.i. 41000), lipsoluble black HB (c.i. 26150), morronidazole yellow GT (c.i. pigment yellow 12), permanent yellow GR (c.i. pigment yellow 17), permanent yellow HR (c.i. pigment yellow 83), permanent carmine FBB (c.i. pigment red 146), phthalocyanine red B (c.i. pigment violet 19), permanent ruby red FBH (c.i. pigment red 11), fatter pink B sapra (c.i. pigment red 81), monasterl fast blue (c.i. pigment blue 15), morronidazole fast black B (c.i. pigment black 1), carbon black, c.i. pigment red 97, c.i. pigment red 122, c.i. pigment red 149, c.i. pigment red 168, c.i. pigment red 177, c.i. pigment red 215, c.i. pigment red 192, c.i. pigment green 15, c.i. pigment blue 60, c.i. pigment blue 15, c.i. pigment red 60, c.i. pigment red 15, c.i. pigment red 60, c.i. pigment blue 15. These pigments may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

The solid content of the colored pigment in the solid content of the photosensitive composition can be determined depending on the exposure sensitivity, resolution, and the like of the photosensitive layer at the time of forming a permanent pattern, and varies depending on the type of the colored dye, and is generally preferably 0.05 to 10% by mass, and more preferably 0.1 to 5% by mass.

Filling pigments

The photosensitive composition may contain an inorganic pigment and organic fine particles as necessary for the purpose of increasing the surface hardness of the permanent pattern, reducing the linear expansion coefficient, or reducing the dielectric constant and dielectric dissipation angle of the cured film itself.

The inorganic pigment is not particularly limited, and may be appropriately selected from known inorganic pigments, and examples thereof include: kaolin, barium sulfate, barium titanate, silicon oxide powder, fine powder silicon oxide, fumed silica, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, alumina, aluminum hydroxide, mica, and the like.

The average particle diameter of the inorganic pigment is preferably less than 10 μm, and more preferably 3 μm or less. When the average particle size is 10 μm or more, resolution may be deteriorated due to light dispersion.

The organic fine particles are not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: 3. melamine resins, benzoguanamine resins, crosslinked polystyrene resins, and the like. Further, those having an average particle diameter of 1 to 5 μm and an oil absorption of 100 to 200m can be used ² Silica in the order of/g, spherical porous fine particles made of a crosslinked resin, and the like.

The amount of the filler pigment added is preferably 5 to 60% by mass. When the amount is less than 5% by mass, the linear expansion coefficient may not be sufficiently reduced, and when it exceeds 60% by mass, the film quality of the cured film may become brittle when the cured film is formed on the surface of the photosensitive layer, and the function as a protective film for a circuit may be impaired when a circuit is formed using a permanent pattern.

Adhesion promoters

In order to improve the adhesion between the layers or the adhesion between the photosensitive layer and the substrate, a known adhesion promoter may be used for each layer.

As the adhesion promoter, for example, JP-A-5-11439, JP-A-5-341532 and JP-A-6-43638 can be mentioned. Specific examples include: benzimidazole, benzoxazole, benzothiazole, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, 3-morpholinomethyl-1-phenyl-triazole-2-thiocarbonyl, 3-morpholinomethyl-5-phenyl-oxadiazole-2-thiocarbonyl, 5-amino-3-morpholinomethyl-thiadiazole-2-thiocarbonyl and 2-mercapto-5-methylthio-thiadiazole, triazole, tetrazole, benzotriazole, carboxybenzotriazole, aminobenzotriazole, silane coupling agents, and the like.

The content of the adhesion promoter is preferably 0.001 to 20% by mass, more preferably 0.01 to 10% by mass, and particularly preferably 0.1 to 5% by mass, based on the total components in the photosensitive composition.

The photosensitive composition of the invention has excellent developability, solder heat resistance, folding resistance and moisture resistance, and the flexibility of the cured coating film is greatly improved. Therefore, the photosensitive composition can be widely used for forming permanent patterns such as printed wiring boards (multilayer wiring boards, assembly wiring boards, etc.), color filters, display parts such as column materials, rib materials, spacers, partition walls, etc., holograms, microcomputers, proofs, etc., and particularly, can be suitably used for the photosensitive composition, the permanent pattern, and the method for forming the same of the present invention.

[ photosensitive layer ]

The photosensitive layer is formed using the photosensitive composition of the present invention.

The photosensitive layer is preferably: in the exposure step described later, after the light modulation from the light irradiation device is performed by a light modulation device having at least n line drawing sections for receiving and emitting the light from the light irradiation device, the exposure is performed by light passing through a microlens array in which microlenses having aspherical surfaces capable of correcting aberration caused by deviation of the emission surface in the line drawing section are arranged, or by light passing through a microlens array in which microlenses having lens opening shapes for preventing the light from the peripheral portion of the line drawing section from being incident.

The thickness of the photosensitive layer is not particularly limited and may be appropriately selected according to the purpose, and is, for example, preferably 3 to 100 μm, more preferably 5 to 70 μm.

Examples of the method for forming the photosensitive layer include: the photosensitive composition of the present invention is dissolved, emulsified or dispersed in water or a solvent to prepare a photosensitive composition solution, and the photosensitive composition solution is directly applied to a substrate and dried to perform a lamination method.

The solvent of the photosensitive composition solution is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include: alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, and n-hexanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and 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, and ethylbenzene; halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene, chloroform, 1-trichloroethane, methylene chloride, monochlorobenzene and the like; ethers such as tetrahydrofuran, diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and 1-methoxy-2-propanol; dimethylformamide, dimethylacetamide, dimethylsulfoxide, cyclobutylsulfone, and the like. These substances may be used alone in 1 kind, or may be used in combination in 2 or more kinds. In addition, a known surfactant may be added.

The coating method is not particularly limited and may be appropriately selected according to the purpose, and for example, a method of directly coating the support with a spin coater, a slit spin coater, a roll coater, a die coater, a curtain coater, or the like is used.

The drying conditions vary depending on the components, the type of solvent, the ratio of the solvent used, and the like, and the drying is usually carried out at a temperature of 60 to 110 ℃ for about 30 seconds to 15 minutes.

(permanent Pattern and Pattern Forming method)

The permanent pattern of the present invention is obtained by the pattern forming method of the present invention.

The pattern forming method of the present invention is a method of applying the photosensitive composition of the present invention to the surface of a substrate, drying the composition to form a photosensitive layer, and then exposing and developing the photosensitive layer. In the present invention, since a photosensitive composition having excellent flexibility and folding resistance is used, the photosensitive composition can be applied to a flexible substrate, and can be exposed by a roll and then by a roll, so that productivity is remarkably improved.

The details of the permanent pattern of the present invention will be explained below by the description of the pattern forming method of the present invention.

[ base Material ]

The substrate is not particularly limited, and may be appropriately selected from known materials, from substrates having high surface smoothness to substrates having irregularities on the surface, and is preferably, for example, a plate-shaped substrate (substrate), and specific examples thereof include: a substrate for forming a flexible printed wiring board (e.g., a copper-clad laminate), a glass plate (e.g., a soda-lime glass plate), a synthetic resin film, paper, a metal plate, and the like. Among them, a substrate for forming a flexible printed wiring board is preferable, and a substrate on which a circuit has been formed is particularly preferable in terms of enabling high-density mounting of a semiconductor and the like on a multilayer circuit board, an assembled circuit board, and the like.

The substrate material is formed by exposing the photosensitive layer in a laminate in which the photosensitive layer is formed on the substrate by the photosensitive composition, and the exposed region is cured, thereby forming a permanent pattern by a developing step described later.

-a laminate-

The method of forming the laminate is not particularly limited and may be appropriately selected depending on the purpose, but a laminate obtained by laminating a photosensitive layer formed by applying the photosensitive composition and drying the photosensitive composition on the substrate is preferable.

The method of coating and drying is not particularly limited and may be appropriately selected according to the purpose, and for example, the method may be performed when forming the photosensitive layer in the photosensitive composition, and the method may be performed by the same method as the method of coating and drying the photosensitive composition solution, for example, a method of coating the photosensitive composition solution using a spin coater, a slit spin coater, a roll coater, a die coater, a curtain coater, or the like.

[ Exposure Process ]

The exposure step is a step of: after the light modulation from the light irradiation device, the photosensitive layer formed in the photosensitive layer forming step is exposed by light passing through a microlens array in which microlenses having aspherical surfaces capable of correcting aberration caused by deviation of an emission surface in the line drawing section are arranged or by light passing through a microlens array in which microlenses having a lens opening shape that does not allow light from the peripheral portion of the line drawing section to enter are arranged.

The exposure step includes the steps of: after the light modulation from the light irradiation device, the photosensitive layer formed in the photosensitive layer forming step is exposed by light passing through a microlens array in which microlenses having aspherical surfaces capable of correcting aberrations caused by the deviation of the emission surface in the pixel portion are arrayed, or by light passing through a microlens array in which microlenses having a lens opening shape that does not allow light from the peripheral portion of the pixel portion to enter are arrayed.

In the exposure step, the light irradiated from the light irradiation device is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include electromagnetic waves for activating a photopolymerization initiator and a sensitizer, visible light from ultraviolet rays, electron beams, X-rays, laser beams, and the like, and among these irradiation lights, laser lights in which on/off control of light is performed in a short time and interference control of light is easily performed are appropriately exemplified.

The wavelength of the visible light from ultraviolet rays is not particularly limited and may be appropriately selected according to the purpose, but in order to shorten the exposure time of the photosensitive composition, it is preferably 330 to 650nm, more preferably 395 to 415nm, and particularly preferably 405nm.

The method of irradiating light with the light irradiation device is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include methods of irradiating with a known light source such as a wet mercury lamp, a xenon lamp, a carbon arc lamp, a halogen lamp, a cold cathode tube for a copier, an LED, and a semiconductor laser. For example, it is preferable to irradiate the light sources by combining 2 or more kinds of light, and particularly preferable to irradiate the laser light combined with 2 or more kinds of light (hereinafter, may be referred to as "combined laser light").

The irradiation method of the composite laser beam is not particularly limited, and may be appropriately selected according to the purpose, and for example, a method of irradiating the composite laser beam with a plurality of laser light sources, a multimode optical fiber, and a polymerization optical system for condensing the laser beams irradiated from the plurality of laser light sources and coupling the condensed laser beams to the multimode optical fiber may be used.

The method of modulating the light in the exposure step is not particularly limited as long as the light is modulated by a light modulation device having n line segments for receiving and emitting the light from the light irradiation device, and may be appropriately selected according to the purpose, and a method of controlling any less than n line segments continuously arranged by the n line segments based on pattern information is appropriately exemplified.

The number (n) of the above-mentioned drawing sections is not particularly limited, and may be appropriately selected according to the purpose, and is preferably 2 or more.

The arrangement of the line segments in the light modulation device is not particularly limited, and may be appropriately selected according to the purpose, and for example, the line segments are preferably arranged in a 2-dimensional pattern, and more preferably in a lattice pattern.

The method of modulating the light is not particularly limited, and may be appropriately selected according to the purpose, and a method of using a spatial light modulator in the light modulation device is preferable.

The spatial Light modulation element is not particularly limited, and may be appropriately selected according to the purpose, and for example, a Digital Micromirror Device (DMD), a MEMS (Micro Electro Mechanical Systems) type spatial Light modulation element (SLM; special Light Modulator), an optical element (PLZT element) for modulating transmitted Light by an Electro-optical effect, a liquid crystal Light valve (FCL), and the like are preferable, and among these spatial Light modulation elements, DMD is particularly preferable.

In the exposure step, the light modulated by the modulation device passes through a microlens array in which microlenses having aspheric surfaces capable of correcting aberration caused by deviation of an exit surface in the drawing section are arranged, or a microlens array in which microlenses having a lens opening shape that does not allow light from a peripheral portion of the drawing section to enter are arranged.

The microlenses arranged in the microlens array are not particularly limited, and for example, microlenses having an aspherical surface are preferable, and microlenses having a toric (toric) surface as the aspherical surface are more preferable.

In the exposure step, it is preferable that the light modulated by the modulation device passes through an aperture array, a coupling optical system, another optical system appropriately selected, or the like.

In the exposure step, the method for exposing the photosensitive layer is not particularly limited, and may be appropriately selected depending on the purpose, and for example, there are digital exposure, analog exposure, and the like, and digital exposure is preferable.

The method of the digital exposure is not particularly limited, and may be appropriately selected according to the purpose, and for example, a method of performing exposure using a laser beam modulated according to a control signal generated based on predetermined pattern information is preferable.

In the exposure step, the method of exposing the photosensitive layer is not particularly limited and may be appropriately selected according to the purpose, but from the viewpoint of enabling exposure to be performed in a short time and at a high speed, it is preferable to perform exposure while relatively moving the exposure light and the photosensitive layer, and it is particularly preferable to use the exposure method in combination with the Digital Micromirror Device (DMD).

In the exposure step, exposure may be performed in an inert gas atmosphere. For example, the method of exposing the photosensitive layer formed in the photosensitive layer forming step is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include: a method of blowing an inert gas directly into the surface of the photosensitive layer; and a method of exposing a surface of a photosensitive layer while introducing an inert gas through an inert gas introduction hole and covering the surface of the photosensitive layer with the inert gas, the method including opening one side of a frame-like frame and loading a sample having the photosensitive layer to be exposed in an exposure space in a sample stage having the inert gas introduction hole formed at least in the remaining 1 side.

Further, the exposure space may be a sealed space, and an inert gas may be introduced into the sealed space under reduced pressure.

The inert gas is not particularly limited as long as it can prevent oxygen from inhibiting the polymerization reaction of the photosensitive layer, and may be appropriately selected according to the purpose, and examples thereof include: nitrogen, helium, argon, and the like.

Next, a pattern forming apparatus to which the pattern forming method of the present invention is applied will be described with reference to the drawings.

Fig. 7 is a schematic perspective view showing an external appearance of a pattern forming apparatus to which the pattern forming method of the present invention is applied.

As shown in fig. 7, the patterning device including the optical modulator includes a flat plate-like stage 152 on which a sheet-like patterning material 150 is adsorbed and held on the upper surface of a thick plate-like mounting table 156 supported by 4 frames 154.

The stage 152 is disposed so that its longitudinal direction faces the stage moving direction, and is supported to be movable back and forth by a guide rail 158 formed on the upper surface of the mount 156. The patterning device includes a not-shown driving device for driving the stage 152 along the guide rail 158.

A downward C-shaped door 160 is provided at the center of the mounting table 156 so as to cross the movement path of the stage 152. The ends of the door 160 are fixed to both side surfaces of the longitudinal center portion of the installation base 156. The door 160 is provided with a scanner 162 on one side and a plurality of (e.g., two) detection sensors 164 for detecting the front and rear ends of the pattern forming material 150 on the other side. The scanner 162 and the detection sensor 164 are mounted on the door 160, and are fixedly disposed above the movement path of the stage 152. The scanner 162 and the detection sensor 164 are connected to a controller, not shown, that controls these components.

Fig. 8 is a schematic perspective view showing the configuration of the scanner. Fig. 9A is a plan view showing an exposed region formed in the photosensitive layer. Fig. 9B is a diagram showing the arrangement of exposure regions by the exposure head.

As shown in fig. 8 and 9B, the scanner 162 includes a plurality of (e.g., 14) exposure heads 166 arranged in a substantially matrix form of m rows and n columns (e.g., 3 rows and 5 columns). In this example, 4 exposure heads 166 are arranged in the 3 rd row in relation to the width of the pattern forming material 150. In the case of each of the exposure heads arranged in the m-th row and the n-th column, the reference numeral 166 is an exposure head _mn 。

The exposure region 168 formed by the exposure head 166 is rectangular with the sub-scanning direction set to the short side. Thus, as the stage 152 moves, on the patterning material 150Each exposure head 166 forms a band-shaped exposed region 170. In addition, when an exposure area formed by each of the exposure heads arranged in the m-th row and the n-th column is shown, the mark is an exposure area 168 _mn 。

As shown in fig. 9A and 9B, each line of exposure heads arranged in a line is shifted by a predetermined interval (natural number times longer side of exposure region, 2 times in this example) in the arrangement direction so that the band-shaped exposed regions 170 are arranged without gaps in the direction perpendicular to the sub-scanning direction. Thus, exposure area 168 in row 1 ₁₁ And an exposure region 168 ₁₂ The unexposed portion in between, can pass through the exposure area 168 of row 2 ₂₁ And an exposure area 168 of row 3 ₃₁ And (6) exposing.

Fig. 10 is a perspective view showing a schematic configuration of the exposure head.

As shown in FIG. 10, exposure head 166 ₁₁ ～166 _mn Respectively provided with: a digital micromirror device (hereinafter, sometimes referred to as "DMD") 50 manufactured by us patent publication No. (12461124) 1246138; the fiber array light source 66 is disposed on the light incident side of the DMD50, and includes a laser emitting portion 68 in which the emission end portions (light emitting points) of optical fibers are aligned in a line in a direction corresponding to the longitudinal direction of the exposure region 168; the lens system 67 corrects the laser light emitted from the fiber array light source 66 and condenses the laser light on the DMD; the mirror 69 reflects the laser light transmitted through the lens system 67 toward the DMD 50; the imaging optical system 51 images the laser light B reflected by the DMD50 on the pattern forming material 150.

Fig. 12 is a controller for performing DMD control based on pattern information.

As shown in fig. 12, the DMD50 is connected to a controller 302, which will be described later, including a data processing unit, a transmission control unit, and the like. In the data processing unit of the controller 302, a control signal for controlling each micromirror in the area to be controlled by the DMD50 is generated for each exposure head 166 based on the inputted pattern information. The area to be controlled is as follows. In the mirror driving control unit, the angle of the reflection surface of each micromirror of the DMD50 is controlled for each exposure head 166 based on the control signal generated in the pattern information processing unit.

Fig. 1 is a partially enlarged view showing the configuration of a Digital Micromirror Device (DMD) as the optical modulation device.

As shown in fig. 1, in the DMD50, a plurality of (for example, 1024 × 768) minute mirrors (micromirrors) 62 constituting various pixel drawings (pixels) are mirror devices arranged in a lattice shape in an SRAM cell (memory cell) 60. In each pixel, a micromirror 62 supported by a support is provided at the uppermost part, and a material having high reflectance such as aluminum is vapor-deposited on the surface of the micromirror 62. The reflectance of the micromirror 62 is 90% or more, and the arrangement pitch thereof is an example of 13.7 μm in both the vertical and horizontal directions. Further, a CMOS SRAM cell 60 of a silicon gate manufactured by a manufacturing line of a general semiconductor memory is arranged directly under the micromirror 62 through a support column including a hinge and a support, and the whole is constituted as a monolithic integrated circuit.

Fig. 2A and B are diagrams illustrating the operation of the DMD.

When a digital signal is input to the SRAM cell 60 of the DMD50, the micromirror 62 supported by the support column is inclined within a range of ± α degrees (for example, ± 12 degrees) with respect to the substrate side on which the DMD50 is disposed, centering on the diagonal line. FIG. 2A shows the micromirror 62 tilted + α degrees for the ON state, and FIG. 2B shows the micromirror 62 tilted- α degrees for the OFF state.

Therefore, by controlling the inclination of the micromirrors 62 in each pixel of the DMD50 based on the pattern information, the laser light incident on the DMD50 is reflected in the inclination direction of each micromirror 62.

Fig. 1 shows an example of a state in which the micromirror 62 is controlled to + α degrees or- α degrees. The switching control of the respective micromirrors 62 is performed by the aforementioned controller 302 connected to the DMD 50. In addition, an optical absorber, not shown, is disposed in the direction in which the laser light B reflected by the micromirror 62 in the off state advances.

The DMD50 is preferably arranged with its short side slightly inclined so as to make a predetermined angle θ (for example, 0.1 ° to 5 °) with respect to the sub-scanning direction.

Fig. 3A shows a scanning trajectory of a reflected light image (exposure light beam) 53 formed by each micromirror when the DMD50 is not tilted, and fig. 3B shows a scanning trajectory of the exposure light beam 53 when the DMD50 is tilted.

As shown in fig. 3B, in the DMD50, a plurality of DMD chips (for example, 1024 DMD chips) are arranged in the longitudinal directionA plurality of micromirror rows) arranged in plural groups (for example, 756 groups) in the width direction, and by tilting the DMD50, the pitch P of the scanning locus (scanning line) of the exposure light beam 53 formed by each micromirror ₂ The pitch P of the scanning lines is smaller than that when the DMD50 is not tilted ₁ The resolution can be greatly improved due to the narrow width. On the other hand, since the inclination angle of the DMD50 is small, the scanning width W when the DMD50 is inclined ₂ And a scanning width W when the DMD50 is not tilted ₁ Are substantially the same.

Next, a method for increasing the modulation speed in the optical modulation device (hereinafter referred to as "high-speed modulation") will be described.

When DMD50 is irradiated with laser light B from fiber array light source 66, the laser light emitted from fiber array light source 66 is switched for each line, and pattern forming material 150 is exposed in a number of line units (exposure regions 168) substantially equal to the number of lines used in DMD 50. In addition, by moving the pattern forming material 150 together with the stage 152 at a constant speed, the pattern forming material 150 is sub-scanned by the scanner 162 in the direction opposite to the stage moving direction, and a band-shaped exposed region 170 is formed at each exposure head 166.

Here, since there is a limit to the data processing speed of the entire DMD50 and the modulation speed per 1 line is determined in proportion to the number of line drawings used, the modulation speed per 1 line is increased by using only a part of the microlens arrays. On the other hand, in the case of an exposure system in which the exposure head is continuously moved relative to the exposure surface, it is not necessary to use all of the line drawings in the sub-scanning direction.

In the DMD50, micromirror arrays of 1024 micromirrors are arranged in the main scanning direction, 768 sets of micromirror arrays are arranged in the sub-scanning direction, and the controller 302 controls so as to drive only a part of the micromirror arrays (for example, 1024 × 256 arrays).

Fig. 4A and B are diagrams showing a use area of the DMD.

As shown in fig. 4A, the DMD usage area may use a micromirror array disposed in the center of the DMD50, or may use a micromirror array disposed at the end of the DMD50 as shown in fig. 4B. When a defect occurs in some of the micromirrors, the micromirror array to be used may be changed as appropriate depending on the situation, such as using a micromirror array that does not cause a defect.

For example, when only 384 groups are used in 768 groups of micromirror columns, modulation can be accelerated by 2 times per 1 line compared to the case where 768 groups are used in their entirety. When only 256 groups are used in 768 groups of micromirror arrays, modulation can be performed at a speed up to 3 times per 1 line as compared with the case where all 768 groups are used.

As described above, according to the pattern forming method of the present invention, the DMD having 1,024 micromirror rows in the main scanning direction and 768 micromirror rows in the sub scanning direction is provided, and the modulation speed per 1 line is increased as compared with the case where all the micromirror rows are driven by controlling the DMD so that only a part of the micromirror rows are driven by the controller.

Further, in the case of the example of the micromirror partially driving the DMD, even if the DMD in which a plurality of micromirrors whose angles of the reflecting surfaces can be changed in accordance with various control signals are arranged in a 2-dimensional elongated shape is used on a substrate in which the length of the direction corresponding to the predetermined direction is longer than the length of the direction intersecting the predetermined direction, the number of micromirrors whose angles of the reflecting surfaces are controlled is reduced, and thus the modulation speed can be increased similarly.

The foregoing exposure method can expose the entire surface of the pattern forming material 150 by performing 1 scan in the X direction by the scanner 162, as shown in fig. 5.

As shown in fig. 6A and B, the exposure method may be such that the entire surface of the pattern forming material 150 is exposed by scanning the pattern forming material 150 by a scanner in the X direction, then moving the scanner 162 in the Y direction by 1 pitch, and repeating the scanning and the moving as in the X direction.

The exposure is performed on a partial region of the photosensitive layer to cure the partial region, and an uncured region other than the cured partial region is removed in a developing step described later to form a pattern.

Next, the lens system 67 and the imaging optical system 51 will be explained.

Fig. 11 is a cross-sectional view in the sub-scanning direction along the optical axis of the structure of the exposure head in fig. 10.

As shown in fig. 11, the lens system 67 includes: a condenser lens 71, a rod integrator (hereinafter referred to as a rod integrator) 72, and an imaging lens 74, wherein the condenser lens 71 condenses the laser light B emitted from the fiber array light source 66 as illumination light; the rod integrator 72 is inserted in the optical path of the light passing through the condenser lens 71; the imaging lens 74 is disposed in front of the rod integrator 72, i.e., on the side of the mirror 69.

The condenser lens 71, the rod integrator 72, and the imaging lens 74 make the laser light emitted from the fiber array light source 66 incident on the DMD50 as a light beam which is nearly parallel and has a uniform intensity in the beam cross section.

The laser beam B emitted from the lens system 67 is reflected by a mirror 69, and is irradiated onto the DMD50 through a TIR (total reflection) prism 70. Note that, in fig. 10, the TIR prism 70 is omitted.

As shown in fig. 11, the imaging optical system 51 includes: a 1 st imaging optical system, a 2 nd imaging optical system, a micro lens array 55 and a pinhole array 59, wherein the 1 st imaging optical system is composed of lens systems 52 and 54; the 2 nd imaging optical system is constituted by lens systems 57, 58; the microlens array 55 is interposed between these imaging optical systems.

The microlens array 55 is configured by arranging a plurality of microlenses 55a corresponding to each line of the DMD50 in a 2-dimensional shape. In this example, only 1024 × 256 rows of the 1024 × 768 rows of micromirrors of the DMD50 are driven as described later, and therefore 1024 × 256 rows of microlenses 55a are arranged correspondingly to this.

The arrangement pitch of the microlenses 55a was 41 μm in both the vertical and horizontal directions. The focal length of the microlens 55a is 0.19mm, and NA (aperture number) is 0.11.

The microlens 55a is made of optical glass BK 7.

The beam diameter of the laser light B at the position of each microlens 55a was 41 μm.

The pinhole array 59 is formed with a plurality of pinholes (openings) 59a corresponding to the respective microlenses 55a of the microlens array 55. The diameter of each small hole 59a was 10 μm.

The 1 st imaging optical system images an image formed by the DMD50 on the microlens array 55 at a magnification of 3 times.

The 2 nd imaging system images and projects the image passing through the microlens array 55 on the pattern forming material 150 with a magnification of 1.6 times.

Therefore, the entire optical system enlarges the image formed by the DMD50 by 4.8 times and forms an image, which is projected onto the pattern forming material 150.

Note that the double prism 73 is disposed between the 2 nd imaging optical system and the pattern forming material 150, and the focus of the image on the pattern forming material 150 can be adjusted by moving the double prism 73 in the up-down direction in fig. 11. In the same drawing, the pattern forming material 150 is sub-scanned in the direction of arrow F.

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

Fig. 13A is a cross-sectional view taken along an optical axis showing the configuration of the exposure head.

As shown in fig. 13A, the exposure head includes a light irradiation device 144, lens systems (imaging optical systems) 454 and 458, a microlens array 472, an aperture array 476, and lens systems (imaging optical systems) 480 and 482, wherein the light irradiation device 144 irradiates the DMD50 with laser light; the lens systems (imaging optical systems) 454 and 458 magnify and image the laser light reflected by the DMD 50; a plurality of microlenses 474 corresponding to each of the line segments of the DMD50 are arranged in the microlens array 472; the aperture array 476 is provided with a plurality of apertures 478 corresponding to the respective microlenses of the microlens array 472; the lens systems (imaging optical systems) 480, 482 image the laser light passing through the apertures on the exposed surface 56.

Fig. 14 is a graph showing the measurement results of the flatness of the reflection surfaces of the micromirrors 62 constituting the DMD 50.

In fig. 14, the same height positions of the reflecting surfaces are indicated by contour line connections, and the pitch of the contour lines is 5nm. The x-direction and y-direction are two diagonal directions of micromirror 62. Micromirror 62 rotates about a rotation axis extending to the y-direction as described above.

Fig. 15A and B show the height position displacement of the reflective surface of micromirror 62 along x-direction and y-direction in fig. 14, respectively.

As shown in fig. 14 and 15, the reflective surface of the micromirror 62 has a deflection, and particularly, when the mirror is viewed from the center, the deflection in one diagonal direction (y direction) is larger than the deflection in the other diagonal direction (x direction). Therefore, the following problems occur: the shape of the laser beam B condensed by the microlenses 55a of the microlens array 55 is deviated in the condensing position.

Fig. 16A and B are diagrams showing the front shape and the side shape of the entire microlens array 55.

As shown in fig. 16A, the microlens array 55 is configured by 1024 rows of microlenses 55a arranged in parallel in the vertical direction, corresponding to the micromirrors 62 of the DMD 50.

The microlens array 55 has a dimension of a long side of 50mm and a dimension of a short side of 20mm.

In the same drawing a, the arrangement order of the microlens arrays 55 is denoted by j in the horizontal direction and k in the vertical direction.

Fig. 17A and B are diagrams showing the front and side shapes of microlenses constituting the microlens array. In fig. 17A, the contour lines of the microlenses 55a are shown together.

As shown in fig. 17A and B, the end surface of the microlens 55a on the light exit side is set to an aspherical shape that corrects aberration caused by deflection of the reflection surface of the microlens 62.

The aspherical microlens 55a is a toric (toric) lens, and specifically, has a curvature radius Rx in the x direction of-0.125 mm and a curvature radius Ry in the y direction of-0.1 mm.

Fig. 18 is a schematic view showing a state of light condensing by the micro lens in one cross section a and the other cross section B.

As shown in fig. 18, since the end surface of the microlens 55a constituting the microlens array is a toric lens having an aspherical shape, the focal length of the microlens 55a in the latter cross section is shorter because the state of condensing the laser beam B in the cross section parallel to the x direction and the y direction is smaller than that in the cross section parallel to the x direction and that in the cross section parallel to the y direction.

The microlens 55a may have a 2-order aspherical shape or a higher-order (4-order or 6-order) aspherical shape. By adopting the high-order aspherical shape, the beam shape can be made finer and higher. Further, the foregoing lens shape in which the curvatures in the x direction and the y direction match each other may be adopted in accordance with the deflection of the reflection surface of the micromirror 62. Next, an example of such a lens shape will be described in detail.

The front and side microlenses 55a ″ with contour lines shown in fig. 39A and B have the same curvatures in the x and y directions, respectively, and the curvature Cy of the spherical lens is corrected by the distance h from the lens center. That is, the spherical lens shape that is the basis of the lens shape of the microlens 55a ″ is a shape in which the lens height (the optical axis direction position of the lens curved surface) z is defined by the following calculation formula (formula 1), for example.

[ number 1]

Fig. 40 is a graph showing the relationship between the lens height z and the distance h when the curvature Cy = (1/0.1 mm) is used.

Then, the curvature Cy of the spherical lens shape is corrected as shown in the following calculation formula (formula 2) based on the distance h from the lens center, and the lens shape of the microlens 55a ″ is set.

[ number 2]

In the above formula (formula 2), z is defined as in the above formula (formula 2), and the curvature Cy is corrected by the 4-degree coefficient a and the 6-degree coefficient b. The curvature Cy = (1/0.1 mm), and the 4-order coefficient a =1.2 × 10 ³ Coefficient a =5.5 × 10 for 6 orders ⁷ The relationship between the lens height z and the distance h is plotted in fig. 41.

The end surface shape of the light emitting surface of the microlens 55a is set to be a toric (toric) surface, and one of the two light-passing end surfaces is set to be a spherical surface and the other is set to be a cylindrical surface.

Fig. 19A, B, C, and D are diagrams showing the results of computer simulation of the beam diameter in the vicinity of the condensing position (focal position) of the microlens 55 a.

For comparison, fig. 20A, B, C, and D show the results of the same simulation for the case where the microlens 55a has a spherical shape with a radius of curvature Rx = Ry = -0.1mm. In the figures, the z value represents the evaluation position of the microlens 55a in the focal direction by the distance from the light beam emitting surface of the microlens 55 a.

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

[ number 3]

In the above calculation formula, cx is a curvature (= 1/Rx) in the X direction, cy is a curvature (= 1/Ry) in the Y direction, X is a distance of a lens optical axis O in the X direction, and Y is a distance of the lens optical axis O in the Y direction.

As is clear from comparison between fig. 19A to D and fig. 20A to D, in the pattern forming method of the present invention, the microlens 55a is set to a toric (otic) surface lens having a smaller focal length in a cross section parallel to the y direction than in a cross section parallel to the x direction, thereby suppressing the deviation of the beam shape in the vicinity of the converging position. Therefore, a higher-definition image without deflection can be exposed on the pattern forming material 150.

In the case where the relationship between the magnitudes of the deflections of the central portions of the micromirrors 62 in the x-direction and the y-direction is reversed from the above, if the microlenses are formed of a tollgate lens in which the focal length in a cross section parallel to the x-direction is shorter than the focal length in a cross section parallel to the y-direction, it is possible to expose a higher-definition image without deflection on the pattern forming material 150.

Further, an aperture array 59 is disposed near the light converging position of the microlens array 55. Each of the small holes 59a provided on the small hole array 59 is incident only light passing through the microlens 55a corresponding thereto. Therefore, on the 1 pinhole 59A corresponding to the 1 microlens 55a, light from the adjacent microlens 55a not corresponding thereto is prevented from being incident, and the extinction ratio can be improved.

If the diameter of the pinhole 59a is reduced to some extent, the effect of suppressing the beam shape from deviating at the light converging position of the microlens 55a can be obtained, but the light use efficiency is lowered as the amount of light blocked by the pinhole array 59 becomes larger. At this time, by setting the microlens 55a to the aspherical shape, light blocking is prevented, and light use efficiency is secured efficiently.

Further, although the aberration caused by the deflection of the reflection surface of the micro mirror 62 constituting the DMD50 is corrected by the micro lens array 55 and the pinhole array 59, even when there is a deflection on the surface of the line drawing portion of the spatial light modulation element in the pattern forming method of the present invention using a spatial light modulation element other than the DMD, the aberration caused by the deflection can be corrected by applying the present invention, and the deflection in the beam shape can be prevented.

In the pattern forming method of the present invention, a microlens 55a is applied, the microlens 55a being a troop lens having different curvatures in the x direction and the y direction optically corresponding to the two diagonal directions of the micromirror 62, and a microlens 55a' consisting of a troop lens having different curvatures in the xx direction and the y direction optically corresponding to the two side directions of the rectangular micromirror 62 can be applied according to the deflection of the micromirror 62, as the front shape and the side shape with contour lines shown in fig. 38A and B, respectively.

As shown in fig. 13A, the imaging optical system includes lenses 480 and 482, and the light passing through the aperture array 59 is imaged on the exposed surface 56 by the imaging optical system.

As described above, since the laser beam reflected by the DMD50 is projected onto the exposure surface 56 in a magnified manner by the magnifying lenses 454 and 458 of the lens system in the patterning device, the entire image area is enlarged. At this time, if the microlens array 472 and the aperture array 476 are not arranged, as shown in fig. 13B, the 1-sketch size (spot size) of each beam spot BS projected on the exposure target surface 56 becomes a large size in accordance with the size of the exposure area 468, and the MTF (Modulation Transfer Function) characteristic showing the sharpness of the exposure area 468 is degraded.

On the other hand, in the patterning device, since the microlens array 472 and the aperture array 476 are provided, the laser light reflected by the DMD50 is condensed by each microlens of the microlens array 472 corresponding to each line drawing portion of the DMD 50. Therefore, as shown in fig. 13C, 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 high-definition exposure can be performed while preventing the MTF characteristic from being degraded.

The reason why the exposure region 468 is inclined is that the DMD50 is arranged so as to be inclined so as not to generate a gap between the line drawings.

Even if the light beam is thick due to the aberration of the microlens, the light beam can be shaped by the aperture array so that the spot size on the exposure surface 56 becomes a constant size, and the crosstalk between adjacent line drawings can be prevented by passing the light beam through the aperture array provided corresponding to each line drawing.

Further, since the light irradiation device 144 uses a high-brightness light source, the angle of the light flux incident from the lens 458 to each microlens of the microlens array 472 becomes small, and therefore, it is possible to prevent a part of the light flux of the adjacent line drawing from being incident. That is, a high extinction ratio can be achieved.

Fig. 22A and B are diagrams showing the front shape and the side shape of another microlens array.

As shown in fig. 22, the other microlens arrays maintain a refractive index distribution for correcting aberration caused by deflection of the reflection surface of the micromirror 62 on each microlens.

As shown, the outer shape of the other microlenses 155a is a parallel flat plate. The x and y directions in the same drawing are as described above.

Fig. 23 is a schematic view showing a state in which the laser beam B is condensed in a cross section parallel to the x direction and the y direction by the microlens 155a of fig. 22.

As shown in fig. 23, the microlens 155a has a refractive index distribution that gradually increases outward from the optical axis O, and in the same figure, a broken line shown inside the microlens 155a indicates a position where the refractive index changes at a predetermined equal pitch from the optical axis O. As shown in the figure, when compared between a cross section parallel to the x direction and a cross section parallel to the y direction, the proportion of the refractive index change of the microlens 155a in the cross section of the latter is larger, and the focal distance is shorter. Even when a microlens array including such a gradient index lens is used, the same effect as that obtained when the microlens array 55 is used can be obtained.

In the microlens 55a shown in fig. 17 and 18, aberration caused by deflection of the reflection surface of the micromirror 62 can be corrected by both the surface shape and the refractive index distribution while giving the refractive index distribution.

Next, another example of the microlens array will be described with reference to the drawings.

As shown in fig. 42, the microlens array of the present example is configured by arranging microlenses having an opening shape that prevents light from the peripheral portion of the drawing section from entering.

As described above with reference to fig. 14 and 15, the deflection is present on the reflection surface of micromirror 62 of DMD50, and the amount of change in deflection tends to increase gradually from the center to the peripheral portion of micromirror 62. Further, the amount of change in deflection of the peripheral portion of the micromirror 62 in one diagonal direction (y direction) is larger than the amount of change in deflection of the peripheral portion in the other diagonal direction (x direction), and the above tendency is more remarkable.

The microlens array of this example is an array suitable for coping with the above problem. The microlens array 255 has a structure in which microlenses 255a arranged in an array form have circular lens openings. Therefore, it is possible to prevent the laser beam B reflected by the peripheral portion of the reflection surface of the micromirror 62 having a large deflection, particularly the four corners, from being not condensed by the microlens 255a, and prevent the shape of the condensed laser beam B from being deflected at the condensed position. Therefore, a skew-free, higher-definition image can be exposed on the pattern forming material 150.

In the microlens array 255, as shown in fig. 42, a light-shielding mask 255c is formed so as to embed the outer region of the lens opening of the plurality of microlenses 255a separated from each other in the rear surface of the transparent member 255b (which is usually formed integrally with the microlenses 255 a), that is, the surface opposite to the surface on which the microlenses 255a are formed, which holds the microlenses 255 a. By providing such a mask 255c, the laser beam B reflected at the peripheral portion of the reflecting surface of the micromirror 62, particularly at the four corners, is absorbed and blocked, and therefore, the problem of the shape deviation of the condensed laser beam B can be more reliably prevented.

In the microlens array 255, the opening shape of the microlenses is not limited to the circular shape described above, and for example: as shown in fig. 43, a microlens array 455 is formed by arranging a plurality of microlenses 455a having elliptical openings in parallel; as shown in fig. 44, a microlens array 555 in which a plurality of microlenses 555a having polygonal (in the illustrated example, quadrangular) openings are arranged in parallel, and the like. The microlenses 455a and 555a are microlenses formed by cutting a portion of a normal axisymmetric spherical lens into a circular or polygonal shape, and have a light-condensing function similar to that of a normal axisymmetric spherical lens.

Further, in the present invention, a microlens array as shown in fig. 45A, B, and C may also be applied. The microlens array 655 shown in fig. a is arranged on the surface of the transparent member 655B on the side from which the laser beam B is emitted, so that a plurality of microlenses 655a similar to the microlenses 55a, 455a, and 555a are in close contact with each other, and a mask 655c similar to the mask 255c is formed on the surface on the side from which the laser beam B is incident. Note that, in contrast to the mask 255c of fig. 42 which is formed in the outer portion of the lens opening, the mask 655c is provided in the lens opening. Further, as in the microlens array 755 shown in fig. B, a plurality of microlenses 755a are provided in parallel on the surface of the transparent member 455B on the side from which the laser light B is emitted, and a mask 755c is formed between the microlenses 755 a. Further, as with the microlens array 855 shown in fig. C, a plurality of microlenses 855a are provided side by side on the surface of the transparent member 855B on the side from which the laser light B is emitted, the microlenses 855a being connected to each other, and a mask 855C is formed at the peripheral portion of each of the microlenses 855 a.

The masks 655c, 755c, and 855c all have a circular opening in the same manner as the mask 255c, and therefore, the openings of the microlenses are defined to be circular.

As described above with respect to the microlenses 255a, 455a, 555a, 655a, and 755a, the configuration of the lens opening shape in which light from the peripheral portion of the micromirror 62 of the DMD50 is not incident by providing a mask or the like may be adopted in combination with a lens having an aspherical shape for correcting aberration caused by the deflection of the surface of the micromirror 62, such as the microlens 55a described above shown in fig. 17, and a lens having a refractive index distribution for correcting the aberration, such as the microlens 155a shown in fig. 22. This improves the effect of preventing the deviation of the exposure image due to the deviation of the reflection surface of the micromirror 62 by several times.

In particular, as shown in fig. 45C, in the configuration in which the mask 855C is formed on the lens surface of the microlens 855a in the microlens array 855, the microlens 855a is set to a lens having an aspherical shape and a refractive index distribution as described above, and in addition, for example, when the imaging position of the 1 st imaging optical system of the lens systems 52 and 54 shown in fig. 11 is set on the lens surface of the microlens 855a, the light use efficiency can be particularly improved, and the pattern forming material 150 can be exposed to light with higher intensity. That is, at this time, light is refracted by the 1 st imaging optical system so that stray light caused by the deflection of the reflection surface of the micromirror 62 is focused on the imaging portion of the optical system, but if the mask 855c is formed at this position, light other than the stray light cannot be blocked, and the light use efficiency is improved.

In the pattern forming method of the present invention, the pattern forming apparatus may be used in combination with another optical system selected from known optical systems as appropriate, for example, a light amount distribution correction optical system including a pair of combination lenses.

The light quantity distribution correction optical system corrects the light quantity distribution on the surface to be irradiated so as to be substantially uniform when the DMD is irradiated with the parallel light beam from the light irradiation device, by changing the light beam width at each of the output portions so that the ratio of the light beam width at the peripheral portion to the light beam width at the central portion close to the optical axis is smaller on the output side than on the input side. Next, the light amount distribution correcting optical system will be described with reference to the drawings.

Fig. 24 is an explanatory diagram illustrating a concept of correction by the light amount distribution correcting optical system.

As shown in fig. 24A, the case where the incident light beam and the emitted light beam have the same total beam width (total beam width) H0 and H1 will be described. In fig. 24A, portions denoted by reference numerals 51 and 52 are assumed to represent an incident surface and an emission surface in the light amount distribution correcting optical system.

In the light intensity distribution correcting optical system, the beam widths h0 and h1 of the light flux incident on the central portion close to the optical axis Z1 and the light flux incident on the peripheral portion are set to be the same (h 0= h 1). The light amount distribution correction optical system functions as: with respect to the light of the same beam widths h0, h1 in the incident side, the beam width h0 thereof is enlarged for the incident beam in the center portion; conversely, the beam width h1 is reduced with respect to the incident beam on the peripheral portion. That is, the width h10 of the outgoing beam at the center and the width h11 of the outgoing beam at the peripheral portion are set to h11 < h10. When expressed by the ratio of the beam widths, the ratio of the beam width of the peripheral portion to the beam width of the central portion on the emission side, which is "11/h 10", is smaller than the ratio on the incidence side (h 1/h0= 1) ((h 11/h 10) < 1).

By changing the beam width as described above, the central portion of the light flux having a large light quantity distribution can be generated to the peripheral portion having a small light quantity, and the light utilization efficiency as a whole is not lowered, so that the light quantity distribution on the irradiation surface can be substantially uniform. The degree of homogenization is: for example, the light amount unevenness in the effective region is within 30%, preferably within 20%.

The operation and effect of the light amount distribution correcting optical system are similar even when the entire beam width is changed between the incident side and the emission side (fig. 24B and C).

Fig. 24B shows a case where the entire incident-side beam width H0 is "reduced" to a width H2 and emitted (H0 > H2). Even in this case, the light amount distribution correcting optical system causes light having the same beam widths h0 and h1 on the incident side to be emitted, and the beam width h10 in the central portion is larger than that in the peripheral portion; conversely, the beam width h11 in the peripheral portion is smaller than that in the central portion. When considered in terms of the demagnification of the beam, it acts to: making the reduction rate of the incident beam relative to the central part smaller than that of the peripheral part; the incident beam is reduced more than the center portion with respect to the peripheral portion. At this time, the ratio "H11/H10" of the beam width at the peripheral portion to the beam width at the central portion is smaller than the ratio (H1/H0 = 1) at the incident side ((H11/H10) < 1).

Fig. 24C shows a case where the entire incident-side beam width H0 is "enlarged" to be the width H3 and emitted (H0 < H3). Even in this case, the light amount distribution correcting optical system causes light having the same beam widths h0 and h1 on the incident side to be emitted, and the beam width h10 in the central portion is larger than that in the peripheral portion; conversely, the beam width h11 in the peripheral portion is smaller than that in the central portion. When considered in terms of the magnification of the beam, it plays a role: making the incident beam magnification relative to the central part larger than that of the peripheral part; the incident beam has a smaller magnification relative to the peripheral portion than the central portion. At this time, the ratio "H11/H10" of the beam width at the peripheral portion to the beam width at the central portion is smaller than the ratio (H1/H0 = 1) at the incident side ((H11/H10) < 1).

As described above, since the light amount distribution correction system changes the beam width at each emission position so that the beam width at the peripheral portion is smaller than the emission side than the incidence side with respect to the central portion closer to the optical axis Z1, the beam width at the central portion is larger than the peripheral portion on the emission side and the beam width at the peripheral portion is smaller than the central portion on the incidence side. Thus, the light flux in the central portion can be generated toward the peripheral portion, and a light flux cross section having a substantially uniform light quantity distribution can be formed without lowering the light use efficiency of the entire optical system.

Next, 1 example of specific lens data of 1 pair combined lenses used as the light amount distribution correcting optical system is shown. This example shows lens data when the light quantity distribution in the cross section of the emitted light beam is a gaussian distribution as described above when the light irradiation device is a laser array light source. When a single semiconductor laser is connected to the incident end of the single-mode optical fiber, the light amount distribution of the outgoing light beam from the optical fiber is gaussian. Such a case can be applied to the pattern forming method of the present invention. Further, the configuration in which the core diameter of the multimode optical fiber is reduced to be close to that of the single mode optical fiber can be applied to the case where the amount of light near the center of the optical axis is larger than that of the peripheral portion.

The basic lens data are shown in table 1 below.

[ Table 1]

Basic lens data
				Si (noodle number)	ri (radius of curvature)	di (surface spacing)	Ni (refractive index)
01 02 03 04	Aspherical surface ∞ ∞ Aspherical surface	5.000 50.000 7.000	1.52811 1.52811

As can be seen from table 1, the 1-pair combined lens is composed of two aspherical lenses which are rotationally symmetric. When the surface of the 1 st lens disposed on the light incident side is set as the 1 st surface and the surface on the light emitting side is set as the 2 nd surface, the 1 st surface is an aspherical surface. When the surface of the 2 nd lens disposed on the light emitting side on the light incident side is set to the 3 rd surface and the surface on the light emitting side is set to the 4 th surface, the 4 th surface is an aspherical surface.

In table 1, surface number Si indicates the number of the surface of i number (i =1 to 4), curvature radius ri indicates the curvature radius of the surface of i number, and surface interval di indicates the surface interval on the optical axis between the surface of i number and the surface of i +1 number. The units of the face separation di values are millimeters (mm). The refractive index Ni represents a value of a refractive index at a wavelength of 405nm with respect to the optical element having i-series surfaces.

The aspherical surface data of the 1 st and 4 th surfaces are shown in table 2 below.

[ Table 2]

Aspheric data
				1 st plane	No. 4 surface
C K a3 a4 a5 a6 a7 a8 a9 a10	-1.4098E-02 -4.2192E+00 -1.0027E-04 3.0591E-05 -4.5115E-07 -8.2819E-09 4.1020E-12 1.2231E-13 5.3753E-16 1.6315E-18	-9.8506E-03 -3.6253E+01 -8.9980E-05 2.3060E-05 -2.2860E-06 8.7661E-08 4.4028E-10 1.3624E-12 3.3965E-15 7.4823E-18

The aspherical surface data is expressed by coefficients in the following formula (a) representing an aspherical surface shape.

[ number 4]

In the above formula (a), each coefficient is defined as follows.

Z: length (mm) of perpendicular line from a point on the aspherical surface at a height p from the optical axis to a tangent plane (plane perpendicular to the optical axis) at the apex of the aspherical surface

ρ: distance from the optical axis (mm)

K: coefficient of cone

C: paraxial curvature (1/r, r: radius of curvature of paraxial)

ai: aspherical surface coefficient at i-th order (i =3 to 10)

In the numerical values shown in table 2, the symbol "E" indicates that the numerical value immediately below is a "power exponent" to the base 10, and the numerical value represented by the exponential relationship to the base 10 is the numerical value before being multiplied by "E". For example, "1.0E-02" means "1.0X 10 ^-2 ”。

Fig. 26 shows the light quantity distribution of the illumination light obtained by the 1-pair combination lens shown in table 1 and table 2. The horizontal axis represents coordinates from the optical axis, and the vertical axis represents a light amount ratio (%). For comparison, fig. 25 shows a light amount distribution (gaussian distribution) of illumination light when no correction is performed.

As shown in fig. 25 and 26, by performing correction with the light amount distribution correcting optical system, a substantially uniform light amount distribution is obtained as compared with when no correction is performed. Therefore, uniform laser light can be used to perform uniform exposure without lowering the light use efficiency.

Next, the fiber array light source 66 as a light irradiation device will be explained.

Fig. 27A (a) is a perspective view showing a configuration of a fiber array light source, fig. 27A (B) is a partially enlarged view of (a), and fig. 27A (C) and (D) are plan views showing an arrangement of light emitting points in a laser emitting portion. Fig. 27B is a front view showing an arrangement of light emitting points in a laser emitting portion of the fiber array light source.

As shown in fig. 27A, the fiber array light source 66 is provided with 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. At the other end of the multimode optical fiber 30, an optical fiber 31 having the same core diameter as the multimode optical fiber 30 and a smaller cladding diameter than the multimode optical fiber 30 is coupled. As shown in detail in fig. 27B, 7 ends of the multimode optical fiber 31 on the opposite side of the optical fiber 30 are arranged in the main scanning direction perpendicular to the sub scanning direction, and the laser emitting portions 68 are formed by arranging the ends in 2 rows.

As shown in fig. 27B, the laser emitting portion 68 is sandwiched and fixed by 2 flat-surface supporting plates 65. In addition, it is desirable to dispose a transparent protective plate such as glass on the light emitting end surface of the multimode optical fiber 31 for protection. The light emitting end surface of the multimode optical fiber 31 is likely to collect dust and deteriorate due to its high optical density, but the arrangement of the protective plate as described above can prevent dust from adhering to the end surface and also delay deterioration.

In order to arrange the emission ends of the optical fibers 31 having a small cladding diameter in 1 row without a gap, the multimode optical fibers 30 are stacked between the adjacent 2 multimode optical fibers 30 in a portion having a large cladding diameter, and the emission ends of the optical fibers 31 joined to the stacked multimode optical fibers 30 are arranged so as to be sandwiched between the two emission ends of the optical fibers 31 joined to the adjacent 2 multimode optical fibers 30 in a portion having a large cladding diameter.

As shown in fig. 28, such an optical fiber can be obtained by coaxially coupling an optical fiber 31 having a small cladding diameter and a length of 1 to 30cm to the tip portion on the laser light emission side of a multimode optical fiber 30 having a large cladding diameter. The 2 optical fibers were fusion-bonded such that the incident end face of the optical fiber 31 was fusion-bonded to the emission end face of the multimode optical fiber 30, and the central axes of both the optical fibers were aligned. As described above, the diameter of the core 31a of the optical fiber 31 is the same size as the diameter of the core 30a of the multimode optical fiber 30.

The short-sized optical fiber having a small cladding diameter can be fused to the long, short-clad optical fiber having a large cladding diameter, and can be coupled to the output end of the multimode optical fiber 30 by a ferrule, an optical connector, or the like. The optical fiber can be coupled by engaging and disengaging with a connector or the like, so that the exchange of the tip portion becomes easy when the optical fiber having a small cladding diameter is damaged, and the cost required for the maintenance of the exposure head can be reduced. Hereinafter, the optical fiber 31 may be referred to as an output end of the multimode optical fiber 30.

The multimode optical fiber 30 and the optical fiber 31 may be any of a step-index optical fiber, a graded-index optical fiber, and a composite optical fiber. For example, a graded index optical fiber manufactured by mitsubishi electric corporation can be used. In the present embodiment, the multimode optical fiber 30 and the optical fiber 31 are step-index optical fibers, and the multimode optical fiber 30 has a cladding diameter =125 μm, a core diameter =50 μm, NA =0.2, and a transmittance of an incident end surface layer =99.5% or more; the fiber 31 had a cladding diameter =60 μm, a core diameter =50 μm, and NA =0.2.

In general, in a laser in the infrared region, when the cladding diameter of an optical fiber is reduced, the propagation loss increases. Therefore, an appropriate cladding diameter is determined according to the wavelength band of the laser. However, the shorter the wavelength, the smaller the propagation loss, and in the laser beam of 405nm wavelength emitted from the GaN-based semiconductor laser, the propagation loss hardly increases even if the thickness { (cladding diameter-core diameter)/2 } of the cladding layer is set to about 1/2 of the thickness when the infrared light of 800nm wavelength band is propagated and about 1/4 of the thickness when the infrared light of 1.5 μm wavelength band for communication is propagated. 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 cladding diameter of the optical fiber used in the conventional fiber array light source is 125 μm, but the smaller the cladding diameter, the deeper the focal depth, and therefore, the cladding diameter of the multimode optical fiber is preferably 80 μm or less, more preferably 60 μm or less, and further preferably 40 μm or less. On the other hand, since the core diameter must 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 is constituted by a composite laser light source (fiber array light source) as shown in fig. 29. The light source of the wave-combining laser is composed of the following components: a plurality of (for example, 7) sheet-like lateral multimode or single mode GaN-based semiconductor lasers LD1, LD2, LD3, LD4, LD5, LD6, and LD7 arranged and fixed to the heating block 10; collimator lenses 11, 12, 13, 14, 15, 16, and 17 provided corresponding to the GaN-based semiconductor lasers LD1 to LD7, respectively; a condenser lens 20;1 multimode optical fiber 30. The number of semiconductor lasers is not limited to 7. For example, in a multimode optical fiber having a cladding diameter =60 μm, a core diameter =50 μm, and NA =0.2, 20 semiconductor lasers can be incident, a required light amount of an exposure head can be realized, and the number of optical fibers can be further reduced.

The GaN-based semiconductor lasers LD1 to LD7 have the same oscillation wavelength (for example, 405 nm) and the same maximum output power (for example, 100mW for the multimode laser and 30mW for the single-mode laser). In the wavelength range of 350nm to 450nm, the GaN-based semiconductor lasers LD1 to LD7 may use a laser having an oscillation wavelength other than 405nm.

As shown in fig. 30 and 31, the multiplex laser light source is stored in a box-shaped package 40 having an upper opening together with other optical elements. The package 40 is provided with a package lid 41 formed so that the opening is closed, and by introducing a sealing gas after degassing treatment, the opening of the package 40 is closed with the package lid 41, and the combined-wave laser light source is hermetically sealed in a sealed space (sealed space) formed by the package 40 and the package lid 41.

A substrate 42 is fixed to the bottom of the package 40, and the heating block 10, a condensing lens holder 45 for supporting the condensing lens 20, and a fiber holder 46 for supporting the incident end of the multimode optical fiber 30 are mounted on the upper surface of the substrate 42. The emission end of the multimode optical fiber 30 is drawn out of the package through an opening formed in a wall surface of the package 40.

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

In fig. 31, in order to avoid complication of the drawing, only the GaN-based semiconductor laser LD7 is numbered among the plurality of GaN-based semiconductor lasers, and only the collimator lens 17 is numbered among the plurality of collimator lenses.

Fig. 32 shows the front shape of the mount portion of the collimator lenses 11 to 17. The collimator lenses 11 to 17 are each formed by cutting out a region including the optical axis of a circular lens having an aspherical surface in a slender shape in parallel planes. The elongated collimator lens can be formed by, for example, molding a resin or an optical glass. The collimator lenses 11 to 17 are closely arranged in the arrangement direction of the light emitting points so that the longitudinal direction thereof is perpendicular to the arrangement direction (the left-right direction in fig. 32) of the light emitting points of the GaN-based semiconductor lasers LD1 to LD 7.

On the other hand, the GaN-based semiconductor lasers LD1 to LD7 include an active layer having an emission width of 2m, and laser beams emitting laser beams B1 to B7 are used in a state of 10 ° and 30 °, respectively, for example, at the magnification angles in the direction parallel to and perpendicular to the active layer. These GaN-based semiconductor lasers LD1 to LD7 are arranged in a direction parallel to the active layer so that the light emitting points are arranged in 1 row.

The laser beams B1 to B7 emitted from the respective light emitting points are incident on the elongated collimator lenses 11 to 17 in a state where the direction of the enlargement angle is large coincides with the longitudinal direction and the direction of the enlargement angle is small coincides with the width direction (direction perpendicular to the longitudinal direction). That is, the width and length of each collimator lens 11 to 17 are 1.1mm and 4.6mm, and the horizontal and vertical beam diameters of the laser beams B1 to B7 incident on these lenses are 0.9mm and 2.6mm, respectively. Further, the focal length f of each collimator lens 11 to 17 ₁ =3mm, NA =0.6, and lens arrangement pitch =1.25mm.

The condenser lens 20 is formed in a shape in which a region including the optical axis of the circular lens having the aspherical surface is cut out to be slender in parallel planes, and the collimator lenses 11 to 17 are arranged in a long direction, i.e., in a horizontal direction and in a short direction perpendicular thereto. A focal length f of the condenser lens 20 ₂ =23mm, na =0.2. The condenser lens 20 is also exemplifiedSuch as resin or optical glass, by molding.

In the light irradiation device for illuminating the DMD, the fiber array light source is used which has high brightness and is formed by arranging the emission ends of the optical fibers of the multiplex laser light source in an array, and thus a patterning device having high output and a deep focal depth can be realized. Further, 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 cost reduction of the patterning device can be achieved.

Further, since the diameter of the cladding at the output end of the optical fiber is made smaller than that at the input end, the diameter of the light emitting section becomes smaller, and the brightness of the fiber array light source can be increased. Therefore, a pattern forming apparatus having a deeper focal depth can be realized. For example, in the case of ultra-high resolution exposure in which the beam diameter is 1 μm or less and the resolution is 0.1 μm or less, a deep depth of focus can be obtained, and high-speed and high-precision exposure can be performed. Therefore, the method is suitable for an exposure process of a Thin Film Transistor (TFT) requiring high resolution.

The light irradiation device is not limited to the fiber array light source including a plurality of the wave-combining laser light sources, and for example, a fiber array light source including 1 optical fiber for emitting laser light incident from a single semiconductor laser light having one light emitting point may be used.

As a light irradiation device provided with a plurality of light emitting points, for example, as shown in fig. 33, a laser array in which a plurality of (for example, 7) sheet-like semiconductor lasers LD1 to LD7 are arranged on a heating block 100 can be used. Further, as shown in fig. 34A, a sheet-like multi-cavity laser 110 in which a plurality of (for example, 5) light emitting points 110a are arranged in a predetermined direction may be used. The multi-cavity laser 110 can arrange light emitting points with a higher positional accuracy than the case of arranging the sheet-like semiconductor lasers, and therefore, it is easy to combine the laser beams emitted from the light emitting points. However, since the multi-cavity laser 110 is likely to be warped during laser production when the number of light-emitting points is increased, the number of light-emitting points 110a is preferably set to 5 or less.

The light irradiation apparatus may use the multi-cavity laser 110 and a multi-cavity laser array in which a plurality of multi-cavity lasers 110 are arranged on a heating block 100 in the same arrangement direction as the arrangement direction of the light emitting points 110a of the respective sheets, as a laser light source, as shown in fig. 34B.

The combined-wave laser light source is not limited to a light source that combines laser beams emitted from a plurality of sheet-like semiconductor lasers.

For example, a combined-wave laser light source including a sheet-like multi-cavity laser 110 having a plurality of (e.g., 3) light emitting points 110a as shown in fig. 21 may be used. The light source of the wave-combining laser is composed of a multi-cavity laser 110, 1 multi-mode optical fiber 130 and a condensing lens 120. The multi-cavity laser 110 may be composed of, for example, a GaN-based laser diode having an oscillation wavelength of 405nm.

In the above configuration, the laser beams B emitted from the light emitting points 110a of the multi-cavity laser 110 are condensed by the condenser lens 120, and are incident on the core 130a of the multi-mode optical fiber 130. The laser light incident on the core 130a propagates through the optical fiber, and the combined wave is emitted as 1 beam.

The plurality of light emitting points 110a of the multi-cavity laser 110 are collectively arranged within a width substantially equal to the core diameter of the multi-mode fiber 130, and the coupling efficiency of the laser beam B to the multi-mode fiber 130 can be improved by using a convex lens having a focal length substantially equal to the core diameter of the multi-mode fiber 130 and a concave lens collimating the light beam emitted from the multi-cavity laser 110 only in a plane perpendicular to the active layer thereof as the condensing lens 120.

As shown in fig. 35, a combined-wave laser light source may be used, which uses a multi-cavity laser 110 having a plurality of (e.g., 3) light-emitting points, and a laser array 140 in which a plurality of (e.g., 9) multi-cavity lasers 110 are arranged at equal intervals on a heating block 111. The plurality of multi-cavity lasers 110 are aligned and fixed in the same direction as the direction in which the light emitting points 110a of the respective chips are aligned.

The multiplexing laser light source includes a laser array 140, a plurality of lens arrays 114 arranged corresponding to the respective multi-cavity lasers 110, one concave lens 113 arranged between the laser array 140 and the plurality of lens arrays 114, 1 multi-mode fiber 130, and a condensing lens 120. The lens array 114 is provided with a plurality of microlenses corresponding to light emitting points of the multi-cavity laser 110.

In the above configuration, the laser beams B emitted from the light emitting points 110a of the multi-cavity lasers 110 are converged in a predetermined direction by the concave lenses 113, and then collimated by the microlenses of the lens array 114. The collimated laser beam L is condensed by the condenser lens 120 and enters the core 130a of the multimode optical fiber 130. The laser light incident on the core 130a propagates through the optical fiber, and is combined into 1 wave to be emitted.

As shown in fig. 36A and B, another combined-wave laser light source is configured such that a heating block 182 having an L-shaped cross section in the optical axis direction is mounted on a substantially rectangular heating block 180, and a storage space is formed between the two heating blocks. On the upper surface of the L-shaped heating block 182, a plurality of (e.g., two) multi-cavity lasers 110 having a plurality of light emitting points (e.g., 5) arranged in an array are arranged and fixed at equal intervals in the same direction as the arrangement direction of the light emitting points 110a of the respective sheets.

A recess is formed in a substantially rectangular heating block 180, and a plurality of (e.g., two) multi-cavity lasers 110 having a plurality of light emitting points (e.g., 5) arranged in an array are arranged on the upper surface of the heating block 180 on the space side so that the light emitting points are on the same vertical plane as the light emitting points of the laser sheet arranged on the upper surface of the heating block 182.

On the laser light emitting side of the multi-cavity laser 110, a collimator lens array 184 in which collimator lenses are arranged so as to correspond to the light emitting points 110a of the respective pieces is disposed. The collimator lens array 184 is disposed such that the longitudinal direction of each collimator lens coincides with the direction in which the magnification angle of the laser beam is large (fast axis direction), and the width direction of each collimator lens coincides with the direction in which the magnification angle is small (slow axis direction). As described above, by arraying and integrating the collimating lenses, it is possible to improve the space utilization efficiency of the laser light, to increase the output power of the combined-wave laser light source, and to reduce the number of components and the cost.

Further, on the laser light emitting side of the collimator lens array 184, 1 multimode optical fiber 130 and a condenser lens 120 that condenses and couples the laser beam on the incident end of the multimode optical fiber 130 are arranged.

In the above configuration, the laser beams B emitted from the light emitting points 110a of the multi-cavity lasers 110 arranged in the laser modules 180 and 182 are collimated by the collimator lens array 184, condensed by the condenser lens 120, and incident on the core 130a of the multimode optical fiber 130. The laser light incident on the core 130a propagates through the optical fiber, and is combined into 1 wave and emitted.

As described above, the combined-wave laser light source can particularly achieve high output power by the multi-stage arrangement of the multi-cavity laser light and the array of the collimator lenses. The use of the combined-wave laser light source makes it possible to constitute a fiber array light source and a bundle fiber light source having higher luminance, and is therefore particularly suitable as a fiber light source of a laser light source of the pattern forming apparatus of the present invention.

The light sources of the above-described multiplex lasers are stored in the ferrules, and a laser module in which the emission end of the multimode optical fiber 130 is pulled out from the ferrule can be configured.

Further, an example in which another optical fiber having the same core diameter as the multimode optical fiber and a smaller cladding diameter than the multimode optical fiber is coupled to the exit end of the multimode optical fiber of the combined wave laser light source to achieve high brightness of the fiber array light source will be described, and for example, a multimode optical fiber having a cladding diameter of 125 μm, 80 μm, 60 μm, or the like, to which another optical fiber is not coupled to the exit end, can be used.

In each exposure head 166 of the scanner 162, the laser beams B1, B2, B3, B4, B5, B6, and B7 emitted in a divergent light state from the GaN-based semiconductor lasers LD1 to LD7 constituting the combined-wave laser light source of the fiber array light source 66 are collimated by the corresponding collimator lenses 11 to 17, respectively. The collimated laser beams B1 to B7 are condensed by the condenser lens 20 and converged on the incident end surface of the core 30a of the multimode optical fiber 30.

The condensing optical system is composed of collimator lenses 11 to 17 and a condensing lens 20. Further, the condensing optical system and the multimode optical fiber 30 constitute a multiplexing optical system.

The laser beams B1 to B7 condensed by the condensing lens 20 as described above are incident on the core 30a of the multimode optical fiber 30, propagate through the fiber, and are emitted from the optical fiber 31 that is coupled to the emission end of the multimode optical fiber 30 by being multiplexed into 1 laser beam.

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 the output powers of the GaN-based semiconductor lasers LD1 to LD7 are 30mW, the combined laser beam B having an output power of 180mW (= 30mW × 0.85 × 7) can be obtained for each of the optical fibers 31 arranged in an array. Therefore, the output power of the laser emitting portion 68 in which 6 optical fibers 31 are arranged in an array is about 1W (= 180mW × 6).

In the laser emitting portion 68 of the fiber array light source 66, light emitting points with high luminance are arranged in 1 row in the main scanning direction. Since the output power of a conventional fiber light source in which laser light from a single semiconductor laser is coupled to 1 optical fiber is low, a desired output power can be obtained only by arranging a plurality of lines, but since the combined-wave laser light source has a high output power, a desired output power can be obtained even with a small number of lines, for example, 1 line.

For example, in a conventional fiber light source in which a semiconductor laser and an optical fiber are bonded in a 1-to-1 manner, a laser having an output of about 30mW (milliwatt) is generally used as the semiconductor laser, and a multimode optical fiber having a core diameter of 50 μm, a cladding diameter of 125 μm, and an NA (number of openings) of 0.2 is used as the optical fiber, so that if an output of about 1W (watt) is desiredIt is necessary to bundle 48 (8 × 6) multimode optical fibers since the area of the light emitting region is 0.62mm ² (0.675 mm. Times.0.925 mm), the brightness of the laser emitting section 68 is 1.6. Times.10 ⁶ (W/m ² ) Brightness of 3.2X 10 per 1 fiber ⁶ (W/m ² )。

In contrast, when the light irradiation device is a device capable of irradiating a multiplexed laser beam, since about 1W of output power can be obtained by using 6 multimode optical fibers, the area of the light emitting region of the laser emitting portion 68 is 0.0081mm ² (0.325 mm. Times.0.025 mm), the brightness at the laser emitting portion 68 is 123X 10 ⁶ (W/m ² ) The luminance can be increased by about 80 times as high as that of the conventional one. In addition, the brightness of each 1 optical fiber is 90 × 10 ⁶ (W/m ² ) The brightness can be increased by about 28 times as high as that of the conventional one.

Here, the difference in focal depth between the conventional exposure head and the exposure head of the present embodiment will be described with reference to fig. 37A and B. The diameter of the light emitting region of the beam-like fiber light source of the conventional exposure head in the sub-scanning direction was 0.675mm, and the diameter of the light emitting region of the fiber array light source of the exposure head in the sub-scanning direction was 0.025mm. As shown in fig. 37A, in the conventional exposure head, since the light emitting region of the light irradiation device (beam-shaped fiber light source) 1 is large, the angle of the light beam incident on the DMD3 becomes large, and as a result, the angle of the light beam incident on the scanning surface 5 becomes large. Therefore, the beam diameter with respect to the condensing direction (shift in the focal point direction) tends to be large.

On the other hand, as shown in fig. 37B, in the exposure head in the pattern forming apparatus of the present invention, since the diameter of the light emitting region of the fiber array light source 66 in the sub-scanning direction is small, the angle of the light beam incident on the DMD50 through the lens system 67 becomes small, and as a result, the angle of the light beam incident on the scanning surface 56 becomes small. 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 as large as that of the conventional one, and the depth of focus substantially corresponding to the diffraction limit can be obtained. Therefore, the method is suitable for exposure of a tiny light spot. The effect on the focal depth is more remarkable and effective as the amount of light required by the exposure head is larger. In this example, the 1-line size projected on the exposure surface is 10 μm × 10 μm. Note that the DMD is a reflective spatial light modulator, and fig. 37A and B are developed views for explaining the optical relationship.

Next, a pattern forming method of the present invention using the aforementioned pattern forming apparatus will be described.

First, pattern information of an exposure pattern is inputted to a controller, not shown, connected to the DMD50, and is stored in a frame memory in the controller at a time. The pattern information is data indicating the density of each line constituting an image by a 2-value (presence or absence of dot recording).

Then, the stage 152 having the pattern forming material 150 adsorbed on the surface thereof is moved at a constant speed along the guide rail 158 from the upstream side to the downstream side of the gate 160 by an unillustrated driving device. When the stage 152 passes under the gate 160 and the leading end of the pattern forming material 150 is detected by the detection sensor 164 mounted on the gate 160, the pattern information stored in the frame memory is sequentially read out on a plurality of lines, and a control signal is generated for each exposure head 166 based on the pattern information read out by the data processing section. The micromirrors of the DMD50 in each exposure head 166 are on-off controlled by the mirror drive control unit based on the generated control signal.

When laser light is irradiated from fiber array light source 66 to DMD50, the laser light reflected when the micromirrors of DMD50 are turned on is formed into an image on exposed surface 56 of pattern forming material 150 by lens systems 54 and 58.

Thus, the laser light emitted from the fiber array light source 66 is switched on and off for each line, and the pattern forming material 150 is exposed in the same number of line units (exposure regions 168) as the number of lines used in the DMD 50.

Further, by moving the pattern forming material 150 together with the stage 152 at a constant speed, the pattern forming material 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162, and a belt-shaped exposed region 170 is formed on each exposure head 166.

[ developing Process ]

The developing step is a step of exposing the photosensitive layer to light in the exposure step to cure the exposed region of the photosensitive layer, and then removing the uncured region to develop the photosensitive layer, thereby forming a permanent pattern.

The method for removing the uncured region is not particularly limited, and may be appropriately selected according to the purpose, and for example, a method of removing the uncured region using a developer is used.

The developing solution is not particularly limited and may be appropriately selected according to the purpose, and is preferably an aqueous solution of a hydroxide or carbonate of an alkali metal or alkaline earth metal, a bicarbonate, ammonia, a quaternary ammonium salt, or the like. Of these solutions, aqueous sodium carbonate solutions are particularly preferred.

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

[ curing treatment Process ]

The pattern forming method of the present invention preferably further comprises a curing step.

The curing step is a step of: after the developing step, the photosensitive layer in the formed permanent pattern is cured.

The curing step is not particularly limited, and may be appropriately selected depending on the purpose, and examples thereof include blanket exposure treatment and blanket heating treatment.

The method of the blanket exposure process includes, for example: and a method of exposing the entire surface of the laminate on which the permanent pattern is formed after the developing step. By this blanket exposure, the curing of the resin in the photosensitive composition forming the photosensitive layer is accelerated, and the surface of the permanent pattern is cured.

The apparatus for performing the blanket exposure is not particularly limited, and may be suitably selected according to the purpose, and examples thereof include a UV exposure apparatus such as an ultra-high pressure silver lamp.

Examples of the method of the overall heat treatment include: and a method of heating the entire surface of the laminate on which the permanent pattern is formed after the developing step. The overall heating improves the film strength of the surface of the permanent pattern.

The heating temperature in the above-mentioned overall heating is preferably 120 to 250 ℃ and more preferably 120 to 200 ℃. When the heating temperature is less than 120 ℃, the film strength may not be improved by the heat treatment, and when it exceeds 250 ℃, the resin in the photosensitive composition may be decomposed to weaken and embrittle the film.

The heating time in the above-mentioned total heating is preferably 10 to 120 minutes, more preferably 15 to 60 minutes.

The device for carrying out the above-mentioned overall heating is not particularly limited, and may be appropriately selected from known devices according to the purpose, for example, a drying oven, an electric heating plate, an IR heater, and the like.

When the substrate is a printed wiring board such as a multilayer circuit board, the permanent pattern of the present invention is formed on the printed wiring board, and soldering can be performed as follows.

That is, the developing step forms a cured layer as the permanent pattern, and exposes the metal layer on the surface of the printed circuit board. After gold plating is performed on the portion of the metal layer exposed on the surface of the printed circuit board, soldering is performed. Further, a semiconductor, a component, and the like are mounted on the soldered portion. At this time, the permanent pattern of the cured layer exerts performance as a protective film or an insulating film (interlayer insulating film), a solder resist pattern, or the like, thereby preventing external impact and conduction between adjacent electrodes.

In the pattern forming method of the present invention, it is preferable to form at least any one of the resist, the interlayer insulating film, and the solder resist pattern. When the permanent pattern formed by the pattern forming method is used as the protective layer, the interlayer insulating film or the solder resist pattern, a circuit can be protected from external impact and bending, and particularly, when the permanent pattern is used as the interlayer insulating film, the permanent pattern is useful for mounting a semiconductor and a component at high density such as a multilayer circuit board and an assembled circuit board.

The pattern forming method of the present invention can form a pattern at high speed, and therefore can be widely used for forming various patterns, and particularly can be applied to the formation of a flexible circuit pattern substrate.

The permanent pattern formed by the pattern forming method of the present invention has excellent surface hardness, insulation properties, heat resistance, and the like, and can be suitably used as a protective film, an interlayer insulating film, and a solder resist pattern.

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples.

(Synthesis example 1)

Synthesis of polyurethane resins having carboxyl groups

125g of 4,4' -diphenylmethane diisocyanate represented by the following structural formula (1) and 67g of 2, 2-bis (hydroxymethyl) propionic acid represented by the following structural formula (2) were dissolved in 290ml of dioxane in a 500ml three-necked flask. Then, 1g of N, N-diethylaniline was added to this solution, and the mixture was stirred under reflux for 6 hours to react with dioxane, and then the resulting solution was added little by little to a solution of 4L of water and 40mL of acetic acid to precipitate a polymer. 185g of a polyurethane resin (A) was synthesized by subjecting the obtained solid to vacuum drying. The acid value of the polyurethane resin (A) was 138mgKOH/g. The weight average molecular weight (in terms of polystyrene) of the polycarbonate resin composition was 28,000 as measured by GPC.

[ solution 4]

Structural formula (1)

Structural formula (2)

(Synthesis example 2)

Synthesis of polyurethane resins having carboxyl groups

In synthesis example 1, a polyurethane resin (B) was synthesized in the same manner as in synthesis example 1 except that a diisocyanate compound represented by the following structural formula (3) was used instead of 4,4' -diphenylmethane diisocyanate. The acid value of the polyurethane resin (B) was 137mgKOH/g.

[ solution 5]

Structural formula (3)

(Synthesis example 3)

Synthesis of polyurethane resins having carboxyl groups

In synthesis example 1, a polyurethane resin (C) was synthesized in the same manner as in synthesis example 1 except that a diisocyanate compound represented by the following structural formula (4) was used instead of 4,4' -diphenylmethane diisocyanate. The acid value of the polyurethane resin (C) was 126mgKOH/g.

[ solution 6]

Structural formula (4)

(Synthesis example 4)

Synthesis of polyurethane resins having carboxyl groups

In synthesis example 1, a polyurethane resin (D) was synthesized in the same manner as in synthesis example 1 except that a diisocyanate compound represented by the following structural formula (5) was used instead of 4,4' -diphenylmethane diisocyanate. The acid value of the polyurethane resin (D) was 172mgKOH/g.

[ solution 7]

OCNCH ₂  ₆ NCO structural formula (5)

(Synthesis example 5)

Synthesis of polyurethane resins having carboxyl groups

In synthesis example 1, a polyurethane resin (E) was synthesized in the same manner as in synthesis example 1 except that a diisocyanate compound represented by the following structural formula (6) was used instead of 4,4' -diphenylmethane diisocyanate. The acid value of the polyurethane resin (E) was 148mgKOH/g.

[ solution 8]

Structural formula (6)

(Synthesis example 6)

Synthesis of polyurethane resins having carboxyl groups

A polyurethane resin (F) was synthesized in the same manner as in synthesis example 1, except that 4,4' -diphenylmethane diisocyanate was substituted with a diisocyanate compound represented by the following structural formula (7) and 2, 2-bis (hydroxymethyl) propionic acid was substituted with a diol compound represented by the following structural formula (8) in synthesis example 1. The acid value of the polyurethane resin (F) was 118mgKOH/g.

[ solution 9]

Structural formula (7)

Structural formula (8)

(Synthesis example 7)

Synthesis of polyurethane resins having carboxyl groups

A polyurethane resin (G) was synthesized in the same manner as in synthesis example 1, except that 4,4' -diphenylmethane diisocyanate was substituted with a diisocyanate compound represented by the following structural formula (9) and 2, 2-bis (hydroxymethyl) propionic acid was substituted with a diol compound represented by the following structural formula (10) in synthesis example 1. The acid value of the polyurethane resin (G) was 130mgKOH/G.

[ solution 10]

Structural formula (9)

Structural formula (10)

(Synthesis example 8)

Synthesis of polyurethane resins having carboxyl groups

In synthesis example 1, a polyurethane resin (H) was synthesized in the same manner as in synthesis example 1, except that 4,4' -diphenylmethane diisocyanate was substituted with a diisocyanate compound represented by the following structural formula (1) and 2, 2-bis (hydroxymethyl) propionic acid was substituted with a diol compound represented by the following structural formula (12). The acid value of the polyurethane resin (H) was 116mgKOH/g.

[ solution 11]

Structural formula (11)

Structural formula (12)

(Synthesis example 9)

Synthesis of polyurethane resins having carboxyl groups

A polyurethane resin (I) was synthesized in the same manner as in synthesis example 1, except that 4,4' -diphenylmethane diisocyanate was substituted with a diisocyanate compound represented by the following structural formula (13) and 2, 2-bis (hydroxymethyl) propionic acid was substituted with a diol compound represented by the following structural formula (14) in synthesis example 1. The acid value of the polyurethane resin (I) was 99mgKOH/g.

[ solution 12]

Structural formula (13)

Structural formula (14)

(Synthesis example 10)

Synthesis of polyurethane resins having carboxyl groups

In synthetic example 1, a polyurethane resin (J) was synthesized in the same manner as in synthetic example 1 except that a diol compound represented by the following structural formula (15) was used instead of 2, 2-bis (hydroxymethyl) propionic acid. The acid value of the polyurethane resin (J) was 88mgKOH/g.

[ solution 13]

Structural formula (15)

(Synthesis example 11)

Synthesis of polyurethane resins having carboxyl groups

A polyurethane resin (K) was synthesized in the same manner as in synthesis example 1, except that a diol compound represented by the following structural formula (16) was used instead of 2, 2-bis (hydroxymethyl) propionic acid in synthesis example 1. The acid value of the polyurethane resin (K) was 82mgKOH/g.

[ solution 14]

Structural formula (16)

(Synthesis example 12)

Synthesis of polyurethane resins having carboxyl groups

A polyurethane resin (L) was synthesized in the same manner as in synthesis example 1, except that 4,4' -diphenylmethane diisocyanate was substituted with a diisocyanate compound represented by the following structural formula (6) and 2, 2-bis (hydroxymethyl) propionic acid was substituted with a diol compound represented by the following structural formula (17) in synthesis example 1. The acid value of the polyurethane resin (L) was 92mgKOH/g.

[ solution 15]

Structural formula (6)

Structural formula (17)

(Synthesis example 13)

Synthesis of polyurethane resins having carboxyl groups

A polyurethane resin (M) was synthesized in the same manner as in synthesis example 1, except that 4,4' -diphenylmethane diisocyanate was substituted with a diisocyanate compound represented by the following structural formula (6) and 2, 2-bis (hydroxymethyl) propionic acid was substituted with a diol compound represented by the following structural formula (18) in synthesis example 1. The acid value of the polyurethane resin (M) was 87mgKOH/g.

[ solution 16]

Structural formula (6)

Structural formula (18)

(comparative Synthesis example 1)

1 equivalent of a cresol novolak type epoxy resin having an epoxy equivalent of 217, an average of 7 phenol core residues in one molecule, and an epoxy group at the same time, and 1.05 equivalents of acrylic acid were reacted. Among the obtained reaction products, 0.69 equivalent of tetrahydrophthalic anhydride was reacted by a conventional method using phenoxyethyl acrylate as a solvent to produce a viscous liquid (epoxy acrylate resin) containing 35 mass% phenoxyethyl acrylate. The epoxy acrylate resin as a mixture showed an acid value of 63.4 mgKOH/g.

(comparative Synthesis example 2)

A flask equipped with a stirrer, a reflux condenser, an inert gas inlet and a thermometer was charged with 1,000g of polytetramethylene ether glycol (PTG, average molecular weight: 1,000) and 405g of sebacic acid, and the mixture was heated to 200 ℃ over 2 hours and reacted for 3 hours, followed by cooling to synthesize a carboxylic acid compound having both ends of polytetramethylene ether glycol having an acid value of 81.9 and a molecular weight of 1,370.

Then, 100g of gamma-butyrolactone and 50g of N-methylpyrrolidone (NMP) were placed in a flask equipped with a stirrer, a reflux condenser, an inert gas inlet, and a thermometer. Then, 55.6g of both terminal carboxylic acid products of the polytetramethylene ether glycol, 6.1g of adipic acid, 8.3g of sebacic acid, 13.7g of isophthalic acid, 13.8g of 4,4' -diphenylmethane diisocyanate (MDI), 14.4g of toluene diisocyanate (124671252512412412412412412412412480, japanese 1250922125125241251257912442, manufactured by industrial corporation), was heated to 200 ℃ and cooled after keeping the temperature for 4 hours, thereby synthesizing a polyamide resin having a heating residue of 40 mass% and an acid value (solid content) of 83.5.

Further, 141.5g of bisphenol a type epoxy resin (v.l \\/1245667124881001 (manufactured by oil \/124711251723 \/12456091246112412471). 10.7g of acrylic acid was added thereto at 120 ℃ and the mixture was incubated for 3 hours, and then 90.6g of tetrahydrophthalic anhydride (THPA) was added thereto and the mixture was incubated for 1 hour. Then, 58.4g of glycidol was added thereto and the mixture was incubated for 2 hours, and then 240g of tetrahydrophthalic anhydride (THPA) was added thereto and the mixture was incubated for 2 hours. Then, the mixture was diluted with Dimethylformamide (DMF), and a photosensitive polyamide resin having a heating residue of 55 mass% and an acid value (solid content) of 145mgKOH/g was synthesized.

(comparative Synthesis example 3)

482.6 parts by mass of α, ω -polybutadiene dicarboxylic acid (NISSO-PB C-1000, manufactured by japan caokada corporation), 400 parts by mass of brominated bisphenol a type epoxy resin (YDB-400 manufactured by sycamore chemical co., ltd.), 183 parts by mass of carbitol acetate and 110 parts by mass of solvent oil (124125231250584124150) were charged into a flask equipped with a stirrer, a reflux condenser and a thermometer, and heated at 110 ℃ for 8 hours. Wherein 36.4 parts by mass of acrylic acid, 0.5 part by mass of methylhydroquinone and 6 parts by mass of carbitol acetate are added, 3 parts by mass of triphenylphosphine and 6 parts by mass of solvent oil are added at 70 ℃, and the mixture is heated to 100 ℃ to react until the acid value of a solid component is below 2 KOHmg/g. Then, the obtained solution was cooled to 50 ℃ and 100 parts by mass of tetrahydrophthalic anhydride, 126 parts by mass of carbitol acetate, and 6 parts by mass of solvent oil were added to the solution to react at 80 ℃ for a predetermined time, thereby synthesizing an unsaturated group-containing polycarboxylic acid resin having a solid acid value of 59KOHmg/g and a solid content of 40 mass%.

100g of gamma-butyrolactone and 50g of N-methylpyrrolidone (NMP) were charged into a flask equipped with a stirrer, a reflux cooler, an inert gas inlet and a thermometer, and then 74.6g of the unsaturated group-containing polycarboxylic acid resin, 3.3g of adipic acid, 4.6g of sebacic acid, 7.5g of isophthalic acid, 4.8g of 4,4' -diphenylmethane diisocyanate (MDI), 13.4g of tolylene diisocyanate (cf. \ 124672512493one \12488t80, jp 1250912522125541255412579125125791251251254). Then, 27.6g of bisphenol a type epoxy resin (\12456091251/124842, manufactured by mitsui petrochemical industry corporation) was added thereto, and after keeping the temperature at 140 ℃ for 2 hours, dimethylformamide (DMF) was added thereto to separate the heating residue into 40 mass%. After 3.3g of methacrylic acid was added thereto at 120 ℃ and the mixture was kept constant for 3 hours, 37.9g of tetrahydrophthalic anhydride (THPA) was added thereto and the mixture was kept constant for 1 hour. Then, the mixture was diluted with Dimethylformamide (DMF) to synthesize a photosensitive polyamide resin having a heat residue of 55 mass% and an acid value (solid content) of 74 mgKOH/g.

200 parts by mass of cresol novolak type epoxy resin (epoxy equivalent: 200), 20 parts by mass of acrylic acid, 0.4 part by mass of methylhydroquinone, 80 parts by mass of carbitol acetate and 20 parts by mass of mineral spirits were charged into a flask equipped with a stirrer, a reflux condenser, an inert gas inlet and a thermometer, and the mixture was heated and stirred at 70 ℃ to dissolve the mixture. Then, the solution was cooled to 50 ℃, 0.5 part by mass of triphenylphosphine was added, and the mixture was heated to 100 ℃ and reacted until the solid acid value became 1KOHmg/g or less. 10 parts by mass of a solvent oil was added to synthesize a resin containing an acrylate group and an epoxy group having a solid content of 67% by mass.

(comparative Synthesis example 4)

First, a copolymer composed of styrene/n-butyl acrylate/maleic anhydride (molar ratio = 41/24/35) was synthesized by a one drop polymerization method.

Then, 103.71 parts by mass of the obtained copolymer was dissolved in 220 parts by mass of methyl ethyl ketone. To this solution, a solution of 36.1 parts by mass of benzylamine and 40 parts by mass of methyl ethyl ketone was added dropwise over 2 hours while stirring at room temperature, and the reaction was further stirred at room temperature for 6 hours to complete the reaction, thereby synthesizing a benzylamine-modified resin solution (solid content 36.8 mass%).

The acid value of the obtained resin was 135KOHmg/g, the weight average molecular weight was 30,000, and the solid content concentration was 36.8% by mass.

(example 1)

Production of flexible printed circuit boards

24.75 parts by mass of a urethane resin (a) of synthesis example 1, 13.36 parts by mass of methoxypropanol, 3.06 parts by mass of a 2-functional propylene monomer (R712, manufactured by japan chemical corporation), 4.59 parts by mass of dipentaerythritol hexaacrylate, 1.98 parts by mass of bis (2, 4, 6-trimethylbenzoyl) -phenylphosphonic oxide (124811249612512512516 \, 12452124124656512559231241252312474, manufactured by MW30HM, tris and v/12465112459, 5.00 parts by mass of a phthalocyanine green dispersion (in 10% by mass of methoxypolylamine) and 1.0 part by mass of a photosensitive composition (manufactured by jp 52125125125611256).

After premixing 30 parts by mass of barium sulfate (made by sakai chemical corporation, B30), 34.29 parts by mass of a 35 mass% methyl ethyl ketone solution of the styrene/maleic anhydride/butyl acrylate copolymer, and 35.71 parts by mass of 1-methoxy-2-propyl acetate, the mixture was dispersed at a peripheral speed of 9M/s for 3.5 hours by using zirconia beads having a diameter of 1.0mm with an electric mill M-200 (made by\124501245212460.

Then, the obtained photosensitive composition solution was applied onto a 2-layer type flexible substrate (copper thickness: 35 μm/resin thickness: 25 μm) by a bar coating method so that the dry film thickness was 35 μm, and dried in an oven at 80 ℃ for 30 minutes to form a photosensitive layer.

< Exposure Process >

A photosensitive layer of a substrate is exposed to a laser beam having a wavelength of 405nm by using a patterning device described below so that a 15-step wedge pattern (Δ logE = 0.15) and a desired circuit pattern are obtained, and a partial region of the photosensitive layer is cured.

Patterning means

A patterning device having the following structure is used, the patterning device having: a combined-wave laser light source shown in fig. 27 to 32 as the light irradiation device, a DMD50 as the optical modulation device, a microlens array 472, and optical systems 480 and 482, wherein the DMD50 controls a microlens array in which 1024 micromirrors are arranged in the main scanning direction shown in fig. 4, and only 1024 × 256 rows are driven in 768 sets of the optical modulation devices arranged in the sub scanning direction; the microlens array 472 arranges the microlenses one surface of which is a tonick surface shown in fig. 13 in an array; the optical systems 480, 482 form images of the light passing through the microlens array on the photosensitive layer.

As shown in fig. 17 and 18, the microlens uses a torquer (toric) lens 55a, and has a radius of curvature Rx = -0.125mm in a direction optically corresponding to the x direction and a radius of curvature Ry = -0.1mm in a direction optically corresponding to the y direction.

The pinhole array 59 disposed near the light collecting position of the microlens array 55 is disposed so that only the light passing through the corresponding microlens 55a is incident on each pinhole 59 a.

Then, spray development was carried out using a 1 mass% aqueous solution of sodium carbonate (spray pressure: 2.0 kgf/cm) ² ) And 60 seconds, removing the unexposed parts. Then, the cured product was heated and cured at 160 ℃ for 1 hour by a circulating oven to produce a flexible printed wiring board.

(example 2)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (B) of synthesis example 2 was used instead of the urethane resin (a) of synthesis example 1 in example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 3)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (C) of synthesis example 3 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 4)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (D) of synthesis example 4 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 5)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (E) of synthesis example 5 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 6)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (F) of synthesis example 6 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 7)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (G) of synthesis example 7 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 8)

Production of flexible printed circuit boards

A photosensitive composition was produced and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (H) of synthesis example 8 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 9)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (I) of synthesis example 9 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 10)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (J) of synthesis example 10 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 11)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (K) of synthesis example 11 was used instead of the urethane resin (a) of synthesis example 1 in example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 12)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (L) of synthesis example 12 was used in example 1 instead of the urethane resin (a) of synthesis example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

(example 13)

Production of flexible printed circuit boards

A photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in example 1, except that the urethane resin (M) of synthesis example 13 was used instead of the urethane resin (a) of synthesis example 1 in example 1. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

Comparative example 1

Production of flexible printed circuit boards

40 parts by mass of the epoxy acrylate resin synthesized in comparative synthesis example 1, 15 parts by mass of 2-hydroxyethyl acrylate, 2.5 parts by mass of benzyl diethyl ketal, 1.0 part by mass of 1-benzyl-2-methylimidazole, 1.0 part by mass of the leveling agent (12514\12501125251 manufactured by U.S. Pat. No. 1251412512531124881), 26 parts by mass of barium sulfate, and 0.5 part by mass of phthalocyanine green were mixed with a triple roll mill to prepare an ink. Then, 15 parts by mass of trimethylolpropane triglycidyl ether was mixed with the obtained ink to prepare a photosensitive composition.

The obtained photosensitive composition solution was coated on the entire surface of a flexible substrate by a screen printing method in the same manner as in example 1, and dried at 80 ℃ for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

Comparative example 2

Production of flexible printed circuit boards

The photosensitive polyamide resin 91 parts by mass, pentaerythritol hexaacrylate 10 parts by mass, cresol novolac acrylic acid adduct 22 parts by mass, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one 7 parts by mass, 2, 4-diethylthioxanthone 1 parts by mass, melamine 2 parts by mass, phthalocyanine green 1 parts by mass, talc 10 parts by mass, barium sulfate 43 parts by mass, silicon oxide 21 parts by mass, triglycidyl isocyanurate 40 parts by mass, and carbitol acetate synthesized in comparative synthesis example 2 were mixed by a triple roll mill to prepare a photosensitive composition.

The obtained photosensitive composition solution was applied to the entire surface of a flexible substrate by screen printing in the same manner as in example 1, and dried at 80 ℃ for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

Comparative example 3

Production of flexible printed circuit boards

25 parts by mass of the unsaturated group-containing polycarboxylic acid resin synthesized in comparative synthesis example 3, 10 parts by mass of the photosensitive polyamide resin synthesized in comparative synthesis example 3, 4.5 parts by mass of 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholino-propan-1-one, 0.5 part by mass of 2, 4-diethylthioxanthone, 4 parts by mass of melamine, 1 part by mass of phthalocyanine green, 20 parts by mass of silica, 15 parts by mass of precipitated barium sulfate, 12 parts by mass of an epoxy resin (ESLV-80 XY, manufactured by Nissan chemical Co., ltd.), 5 parts by mass of the resin containing an acrylate group and an epoxy group synthesized in comparative synthesis example 3, and 3 parts by mass of dipentaerythritol hexaacrylate were mixed by using a triple roll mill to prepare a photosensitive composition.

The obtained photosensitive composition solution was applied to the entire surface of a flexible substrate by screen printing in the same manner as in example 1, and dried at 80 ℃ for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

Comparative example 4

Production of flexible printed circuit boards

13.36 parts by mass of the benzylamine-modified resin synthesized in comparative synthesis example 4, 4.59 parts by mass of dipentaerythritol hexaacrylate, 3.06 parts by mass of a 2-functional acrylic monomer (R712, manufactured by japan chemical company), 1.98 parts by mass of bis (2, 4, 6-trimethylbenzoyl) -phenylphosphonic oxide (a patent publication No. 2,1248112496125patent No. 125124125patent No. 124125patent No. 6,125patent No. 124124125patent No. 1,98; three, 2 parts by mass of a 30 mass% methyl ethyl ketone solution (manufactured by nippon 124521245912523manufactured by 1256), 0.066 part by mass of a phthalocyanine green dispersion (in 10 mass% methoxypropanol), 0.024 part by mass of hydroquinone monomethyl ether, and 24.75 parts by mass of a barium sulfate dispersion were mixed by a triple roll mill, A photosensitive composition was prepared.

The obtained photosensitive composition solution was applied to the entire surface of a flexible substrate by screen printing in the same manner as in example 1, and dried at 80 ℃ for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Then, exposure and development were carried out in the same manner as in example 1 to produce a flexible printed wiring board.

The obtained flexible printed wiring boards of examples 1 to 13 and comparative examples 1 to 4 were evaluated for various properties as described below. The results are shown in tables 3 and 4.

< evaluation of developability >

The surface properties of each of the obtained flexible printed wiring boards after development were evaluated by visual observation using the following criteria.

[ evaluation standards ]

O: after the non-image portion was developed, the composition was completely removed.

And (delta): there was a slight residue in the non-image portion.

X: there is a residue that cannot be developed.

< evaluation of adhesion >

A mesh having a width of 1mm at 100 points was formed on each flexible printed wiring board in accordance with JIS K5400, and a peel test (mesh test) was carried out using a cellophane tape to evaluate the following criteria.

[ evaluation standards ]

O: there was no peeling above 90 in 100.

And (delta): no peeling occurred at 50-90 of 100.

X: no peeling occurred at 0 to 50 of 100.

< evaluation of solder Heat resistance >

Each flexible printed wiring board was coated with rosin flux and immersed in a solder bath at 260 ℃ for 10 seconds. This operation was repeated 6 times, and then the appearance of the flexible printed wiring board was evaluated by the following criteria.

[ evaluation standards ]

O: the appearance was free from peeling and swelling, and solder wrinkles.

X: there is peeling, swelling or solder wrinkling.

< retort resistance test (PCT) >

The respective flexible printed wiring boards were left to stand in water vapor at 121 ℃ and 2 atm for 96 hours, and then the mesh test was performed, and the evaluation was performed by the following criteria.

[ evaluation standards ]

O: there was no peeling above 90 in 100.

And (delta): no peeling occurred at 50-90 of 100.

X: no peeling occurred at 0 to 50 of 100.

< folding endurance >

Examples 1 to 13 and comparative examples were coated on a non-adhesive 2-layer flexible substrate composed of a rolled copper foil (thickness =35 μm) on a polyimide substrate (thickness =25 μm) by a bar coating method or a screen printing methodPhotosensitive layers were formed from the photosensitive compositions of examples 1 to 4. Then, 500mJ/cm was performed ² After the exposure, the cured film (thickness =35 μm) was formed by heating at 160 ℃ for 2 hours, and the bending life (next time) of the cured film was evaluated by bending the cured film to cause cracks in copper under the conditions of temperature = room temperature, frequency =25Hz, stroke =25 mm, and radius of curvature =2mm, using VCMFLEX TEESTER (IPC-FC 241C, JIS-C5016).

[ Table 3]

	Example 1	Example 2	Example 3	Example 4	Example 5	Example 6	Example 7	Example 8	Example 9
										Developability	○	○	○	○	○	○	○	○	○
Adhesion	○	○	○	○	○	○	○	○	○
										Solder heat resistance	○	○	○	○	○	○	○	○	○
Resistance to PCT	○	○	○	○	○	○	○	○	○
										Folding endurance	10000	12000	24000	10000	20000	9000	8000	5000	25000

[ Table 4]

	Example 10	Example 11	Example 12	Example 13	Comparative example 1	Comparative example 2	Comparative example 3	Comparative example 4
									Developability	○	○	○	○	△	○	△	○
Adhesion Property	○	○	○	○	○	○	○	○
									Solder heat resistance	○	○	○	○	○	○	○	○
Resistance to PCT	○	○	○	○	△	×	○	○
									Folding endurance	13000	50000	60000	90000	500	2000	3000	1000

Possibility of industrial application

The photosensitive composition of the present invention is excellent in developability, solder heat resistance, folding resistance and moisture resistance, and the cured film has a greatly improved flexibility, and is suitable for the production of flexible printed wiring boards for mobile phones, various in-vehicle devices, and the like having a movable portion.

Claims (18)

1. A photosensitive composition characterized by containing at least (A) a polyurethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent.

2. The photosensitive composition according to claim 1, wherein the (A) urethane resin having a carboxyl group is formed by reacting a diisocyanate compound represented by the following structural formula (I) with a diol compound represented by any one of the following structural formulae (II) and (III):

[ solution 1]

OCN-R ¹ -NCO of the formula (I)

Structural formula (II)

Structural formula (III)

Wherein, in the structural formulas (I) to (III), R ¹ Represents a divalent hydrocarbon group. R ² Represents a hydrogen atom or a monovalent hydrocarbon group. R ³ ～R ⁵ Each of which may be the same or different represents a divalent hydrocarbon group. Ar represents a trivalent aromatic hydrocarbon group. R ¹ ～R ⁵ And Ar may be further substituted with a substituent, R ² 、R ³ 、R ⁴ And R ⁵ May form a ring.

3. The photosensitive composition according to any one of claims 1 to 2, wherein the acid value of the urethane resin having a carboxyl group (A) is from 80 to 300mgKOH/g.

4. The photosensitive composition according to any one of claims 1 to 3, wherein the thermal crosslinking agent (D) is at least one selected from the group consisting of an epoxy resin compound, an oxetane compound, a polyisocyanate compound, a compound obtained by reacting a blocking agent with a polyisocyanate compound, and a melamine derivative.

5. The photosensitive composition according to any one of claims 1 to 4, which is used for producing a flexible printed wiring board.

6. A pattern forming method comprising applying the photosensitive composition according to any one of claims 1 to 5 to a surface of a substrate, drying the applied composition to form a photosensitive layer, and then exposing and developing the photosensitive layer.

7. The pattern forming method according to claim 6, wherein the photosensitive layer is optically modulated by an optical modulation device having n pixel portions for receiving and emitting light from an optical irradiation device, and then exposed to light by a microlens array having microlenses arranged thereon, the microlenses having aspherical surfaces capable of correcting aberration caused by deflection of an emission surface in the pixel portions.

8. The pattern forming method according to claim 6, wherein the photosensitive layer is optically modulated by an optical modulation device having n line segments for receiving and emitting light from an optical irradiation device, and then exposed by light passing through a microlens array in which microlenses having a lens opening shape for preventing light from the peripheral portion of the line segment from being incident are arranged.

9. The pattern forming method according to claim 8, wherein the microlens has an aspherical surface which can correct aberration caused by a skew of an exit surface in the sketch portion.

10. The pattern forming method according to any one of claims 7 to 9, wherein the aspherical surface is a toric surface.

11. The pattern forming method as claimed in claim 8, wherein the microlens opening shape is a circle.

12. The pattern forming method according to any one of claims 8 to 11, wherein the lens opening shape is defined by providing a light shielding portion on the lens surface.

13. The pattern forming method according to any one of claims 7 to 12, wherein the light modulation device can control any less than n of the plurality of sketch portions which are continuously arranged from the plurality of sketch portions according to the pattern information.

14. The pattern forming method according to any one of claims 7 to 13, wherein the light modulation device is a spatial light modulation element.

15. The pattern forming method as claimed in claim 14, wherein the spatial light modulation element is a Digital Micromirror Device (DMD).

16. The pattern forming method according to any one of claims 7 to 15, wherein the light irradiation device comprises: the multimode optical fiber includes a plurality of lasers, a multimode optical fiber, and a condensing optical system for condensing laser beams irradiated from the plurality of lasers, respectively, and coupling the condensed laser beams to the multimode optical fiber.

17. The pattern forming method as claimed in claim 16, wherein the wavelength of the laser is 395 to 415nm.

18. A permanent pattern formed by the pattern forming method according to any one of claims 6 to 17.

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