JPWO2005124462A1 - Photosensitive composition, pattern forming method and permanent pattern - Google Patents

Abstract

The present invention is excellent in developability, solder heat resistance, folding resistance, pressure cooker resistance, greatly improves the flexibility of the cured film, and is a photosensitive composition suitably used for the production of a flexible printed wiring board, An object is to provide a pattern forming method and a permanent pattern. For this reason, it is a photosensitive composition containing (A) a polyurethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent. A mode in which a polyurethane resin having a group is reacted with a diisocyanate compound represented by the following structural formula (I) and a diol compound represented by either the following structural formula (II) or the following structural formula (III) Is preferred.

Description

  The present invention is excellent in developability, solder heat resistance, folding resistance, pressure cooker resistance, greatly improves the flexibility of the cured film, and is a photosensitive composition suitably used for the production of a flexible printed wiring board, The present invention relates to a pattern forming method and a permanent pattern.

  In recent years, the solder resist in various printed wiring boards has shifted from a thermosetting liquid resist resin by screen printing to a liquid photo solder resist ink of a dilute alkali development type. For example, Patent Document 1 discloses a photocurable resin obtained by reacting a reaction product of a novolak epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride, a photopolymerization initiator, A solder resist ink composition comprising a diluent and an epoxy compound having two or more epoxy groups has been proposed.

  However, in this case, the solder resist ink composition based on the novolak type epoxy resin is excellent in heat resistance due to its structure, but the cured film is hard and brittle, and the adhesion between the coating film and the substrate is inferior. There is a drawback. Therefore, the use of the solder resist ink composition is limited to rigid substrates such as glass epoxy substrates that do not require the flexibility of the cured film.

  However, in recent years, the use of thin and flexible wiring boards (flexible wiring boards) has been increasing for the purpose of simplifying the processing steps, downsizing and increasing the density of the boards, and the like. There is a need for a solder resist ink composition. In order to satisfy this requirement, many proposals have been made for a solder resist ink composition having flexibility. For example, it contains a polycarboxylic acid resin having an unsaturated group, which is a reaction product of a bisphenol A type epoxy resin, an unsaturated monocarboxylic acid, and succinic anhydride, a photopolymerization initiator, a diluent, and a curing agent. A solder resist ink composition has been proposed (see Patent Document 2). However, even in this proposal, folding resistance is insufficient.

In addition, the use of a polyurethane resin that is soluble in a dilute alkaline aqueous solution is being studied as a photosensitive resin. For example, at least one photosensitive resin (A) selected from 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). The photosensitive resin composition to contain is proposed (refer patent document 3).
Patent Document 4 discloses a photosensitive resin (A) having a carboxyl group obtained by reacting an esterified product of an epoxy compound and an unsaturated monocarboxylic acid with a saturated or unsaturated polybasic acid anhydride, and a carboxyl group. At least one photosensitive resin (B) selected from a photosensitive polyamide resin having a carboxyl group and a photosensitive polyamideimide resin having a carboxyl group, an elastomer (C), an epoxy curing agent (D), and a photopolymerization initiator (E ) Containing a photosensitive resin composition has been proposed.

  According to these photosensitive resin compositions, a film having flexibility can be obtained, but other performances required for the resist ink composition, for example, dilute alkali developability, solder heat resistance, The pressure cooker resistance, which is an important performance for the reliability of the board, is still insufficient, and it is desired to provide a photo solder resist ink composition for circuit boards that has these characteristics widely. It is.

Japanese Patent Publication No. 1-54390 JP-A-8-134390 Japanese Patent Laid-Open No. 10-246958 Japanese Patent Laid-Open No. 11-288087

  The present invention is excellent in developability, solder heat resistance, folding resistance, pressure cooker resistance, greatly improves the flexibility of the cured film, and is a photosensitive composition suitably used for the production of a flexible printed wiring board, An object is to provide a pattern forming method and a permanent pattern.

Means for solving the problems are as follows. That is,
<1> A photosensitive composition comprising 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> (A) A polyurethane resin having a carboxyl group is a diisocyanate compound represented by the following structural formula (I) and a diol compound represented by any one of the following structural formula (II) and the following structural formula (III) The photosensitive composition as described in <1> above, wherein
However, 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 to} R ⁵ may be the same as or different from each other, and represent a divalent hydrocarbon group. Ar represents a trivalent aromatic hydrocarbon group. R ^{1 to} R ⁵ and Ar may be further substituted with a substituent, and two or three adjacent R ² , R ³ , R ⁴ and R ⁵ may be linked to form a ring.
<3> (A) The photosensitive composition according to any one of <1> to <2>, wherein the acid value of the polyurethane resin having a carboxyl group is 80 to 300 mgKOH / g.
<4> (D) The above <1, wherein the thermal crosslinking agent is at least one selected from an epoxy resin compound, an oxetane compound, a polyisocyanate compound, a compound obtained by reacting a polyisocyanate compound with a blocking agent, and a melamine derivative. > To <3>.
<5> The photosensitive composition according to any one of <1> to <4>, which is used for producing a flexible printed circuit board.
<6> The photosensitive composition according to any one of <1> to <5> is applied to a surface of a substrate, dried to form a photosensitive layer, and then exposed and developed. This is a pattern forming method.
<7> After the photosensitive layer modulates the light from the light irradiation means by the light modulation means having n drawing parts for receiving and emitting the light from the light irradiation means, the emission surface in the drawing part The pattern forming method according to <6>, wherein the pattern is exposed to light through a microlens array in which microlenses having aspheric surfaces capable of correcting aberration due to distortion are arranged.
<8> After the photosensitive layer modulates the light from the light irradiation means by the light modulation means having n drawing parts for receiving and emitting the light from the light irradiation means, the peripheral portion of the drawing part It is the pattern formation method as described in said <6> exposed by the light which passed through the micro lens array which arranged the micro lens which has the lens opening shape which does not make the light from incident.
<9> The pattern forming method according to <8>, wherein the microlens has an aspherical surface capable of correcting an aberration due to distortion of the exit surface in the pixel portion.
<10> The pattern forming method according to any one of <7> to <9>, wherein the aspherical surface is a toric surface.
<11> The pattern forming method according to <8>, wherein the lens opening shape is circular.
<12> The pattern forming method according to any one of <8> to <11>, wherein the lens opening shape is defined by providing a light shielding portion on the lens surface.
<13> From the <7> to the <12>, wherein the light modulation means can control any less than n number of the graphic elements arranged continuously from the n graphic elements according to the pattern information. > The pattern forming method according to any one of the above.
<14> The pattern forming method according to any one of <7> to <13>, wherein the light modulator is a spatial light modulator.
<15> The pattern forming method according to <14>, wherein the spatial light modulation element is a digital micromirror device (DMD).
<16> The light irradiation means includes a plurality of lasers, a multimode optical fiber, and a collective optical system that collects and couples the laser beams irradiated from the plurality of lasers to the multimode optical fiber. <7> to the pattern forming method according to any one of <15>.
<17> The pattern forming method according to <16>, wherein the laser beam has a wavelength of 395 to 415 nm.
<18> A permanent pattern formed by the pattern forming method according to any one of <6> to <17>.

  The photosensitive composition of the present invention comprises (A) a polyurethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent. The polyurethane resin having a carboxyl group (A) is carried out 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 the cured film has excellent flexibility, adhesion, solder heat resistance, folding resistance, and pressure cooker resistance. It is suitable for manufacturing a substrate.

  According to the present invention, conventional problems can be solved, excellent developability, solder heat resistance, folding resistance, and pressure cooker resistance, the flexibility of the cured film is greatly improved, and a flexible printed wiring board is produced. It is possible to provide a photosensitive composition, a pattern forming method, and a permanent pattern that are suitably used for the above.

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 beam and the scanning line in a case where the DMD is not inclined and in a case where the DMD is inclined. FIG. 3B is an example of a plan view showing the arrangement of the exposure beam and the scanning line in a case where the DMD similar to that in FIG. 3A is not inclined and in a case where the DMD is inclined. FIG. 4A is an example of a diagram illustrating an example of a DMD usage area. FIG. 4B is an example of a diagram illustrating an example of a DMD usage area similar to FIG. 4A. FIG. 5 is an example of a plan view for explaining an exposure method in which the pattern forming material is exposed by one scanning by the scanner. FIG. 6A is an example of a plan view for explaining an exposure method for exposing a pattern forming material by a plurality of scans by a scanner. FIG. 6B is an example of a plan view for explaining an exposure method for exposing the pattern forming material by a plurality of scans by the same scanner as in FIG. 6A. FIG. 7 is an example of a schematic perspective view illustrating an appearance of an example of the pattern forming apparatus. FIG. 8 is an example of a schematic perspective view illustrating the configuration of the 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 areas by each exposure head. FIG. 10 is an example of a perspective view showing a schematic configuration of an exposure head including light modulation means. FIG. 11 is an example of a sectional view in the sub-scanning direction along the optical axis showing the configuration of the exposure head shown in FIG. FIG. 12 is an example of a controller that controls DMD based on pattern information. FIG. 13A is an example of a cross-sectional view along the optical axis showing the configuration of another exposure head having a different coupling optical system. FIG. 13B is an example of a plan view showing a light image projected on the exposure surface when a microlens array or the like is not used. FIG. 13C is an example of a plan view showing a light image projected on the exposed surface when a microlens array or the like is used. FIG. 14 is an example of a diagram showing the distortion of the reflection surface of the micromirror constituting the DMD with contour lines. FIG. 15A is an example of a graph showing the distortion of the reflection surface of the micromirror in two diagonal directions of the mirror. FIG. 15B is an example of a graph showing the distortion of the reflection surface of the micromirror similar to FIG. 15A in two diagonal directions of the mirror. FIG. 16A is an example of a front view of a microlens array used in the pattern forming apparatus. FIG. 16B is an example of a side view of the microlens array used in the pattern forming apparatus. FIG. 17A is an example of a front view of a microlens constituting the microlens array. FIG. 17B is an example of a side view of the microlens constituting the microlens array. FIG. 18A is an example of a schematic diagram illustrating a condensing state by a microlens in one cross section. FIG. 18B is an example of a schematic diagram illustrating a condensing state by a microlens in one cross section. FIG. 19A is an example of a diagram showing the result of simulating the beam diameter in the vicinity of the light condensing position of the microlens of the present invention. FIG. 19B is an example of a diagram illustrating a simulation result similar to FIG. 19B at another position. FIG. 19C is an example of a diagram showing the same simulation result as in FIG. 19A for another position. FIG. 19D is an example of a diagram illustrating simulation results similar to those in FIG. 19A at different positions. FIG. 20A is an example of a diagram showing a result of simulating a beam diameter in the vicinity of a condensing position of a microlens in a conventional pattern forming method. FIG. 20B is an example of a diagram illustrating simulation results similar to those in FIG. 20A at different positions. FIG. 20C is an example of a diagram illustrating the same simulation result as in FIG. 20A for another position. FIG. 20D is an example of a diagram illustrating simulation results similar to those in FIG. 20A at different positions. FIG. 21 is an example of a plan view showing another configuration of the combined laser light source. FIG. 22A is an example of a front view of a microlens constituting the microlens array. FIG. 22B is an example of a side view of the microlens constituting the microlens array. FIG. 23A is an example of a schematic diagram illustrating a condensing state by the microlens of FIGS. 22A and 22B in one cross section. FIG. 23B is an example of a schematic diagram illustrating another cross section of the example of FIG. 23A. FIG. 24A is an example of an explanatory diagram about the concept of correction by the light amount distribution correction optical system. FIG. 24B is an example of an explanatory diagram about the concept of correction by the light amount distribution correction optical system. FIG. 24C is an example of an explanatory diagram about the concept of correction by the light amount distribution correction optical system. FIG. 25 is an example of a graph showing the light amount distribution when the light irradiation means has a Gaussian distribution and the light amount distribution is not corrected. FIG. 26 is an example of a graph showing the light amount distribution after correction by the light amount distribution correcting optical system. 27A (A) is a perspective view showing the configuration of the fiber array light source, FIG. 27A (B) is an example of a partially enlarged view of (A), and FIGS. 27A (C) and (D) are lasers. It is an example of the top view which shows the arrangement | sequence of the light emission point in an emission part. FIG. 27B is an example of a front view showing an array of light emitting points in the laser emitting portion of the fiber array light source. FIG. 28 is an example of a diagram illustrating a configuration of a multimode optical fiber. FIG. 29 is an example of a plan view showing the configuration of the combined laser light source. FIG. 30 is an example of a plan view showing the configuration of the laser module. FIG. 31 is an example of a side view showing the configuration of the laser module shown in FIG. 32 is a partial side view showing the configuration of the laser module shown in FIG. FIG. 33 is an example of a perspective view showing a configuration of a 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 lasers shown in FIG. 34A are arranged in an array. FIG. 35 is an example of a plan view showing another configuration of the combined laser light source. FIG. 36A is an example of a plan view showing another configuration of the combined 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 along the optical axis showing the difference between the depth of focus in a conventional exposure apparatus and the depth of focus by the pattern forming method (pattern forming apparatus) of the present invention. FIG. 37B is an example of a cross-sectional view along the optical axis showing the difference between the depth of focus in the conventional exposure apparatus and the depth of focus by the pattern forming method (pattern forming apparatus) of the present invention. FIG. 38A is a front view showing another example of the microlens constituting the macro array. FIG. 38B is a side view showing another example of the microlens constituting the macro array. FIG. 39A is an example of a front view of a microlens constituting a macro array. FIG. 39B is an example of a side view of the microlens constituting the macro array. FIG. 40 is a graph showing a spherical lens shape example. FIG. 41 is a graph showing another lens surface shape example. 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 microlens array. FIG. 45B is a longitudinal sectional view showing another example of the microlens array. FIG. 45C is a longitudinal sectional view showing another example of the microlens array.

(Photosensitive composition)
The photosensitive composition of the present invention comprises (A) a polyurethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent. Accordingly, it contains other components.

[(A) Polyurethane resin having carboxyl group]
There is no restriction | limiting in particular as said polyurethane resin which has a carboxyl group, According to the objective, it can select suitably, For example, the diisocyanate compound represented by following Structural formula (I), following Structural formula (II), and following Those obtained by reacting with a diol compound represented by any one of structural formula (III) are preferred.

In the 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, amylene, hexylene and the like. The divalent aromatic hydrocarbon group is preferably an arylene group obtained by removing one hydrogen atom from an aryl group, and examples thereof include a phenylene group. R ¹ may have another functional group that does not react with the isocyanate group, such as an ester group, a urethane group, an amide group, or a ureido group. These may be further substituted with a substituent.
Examples of the substituent include a hydroxyl group, a halogen atom, a nitro group, a carboxyl group, a cyano group, an alkyl group, an aryl group, and a heterocyclic group.

R ² in the structural formula (II) represents a hydrogen atom or a monovalent hydrocarbon group. The monovalent hydrocarbon group represents, for example, any one of an alkyl group, an aralkyl group, an aryl group, an alkoxy group, and an aryloxy group, and these may be further substituted with a substituent.
The alkyl group is preferably one having 1 to 8 carbon atoms, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, n-hexyl group, An isohexyl group, n-heptyl group, n-octyl group, isooctyl group, etc. are mentioned.
There is no restriction | limiting in particular as said aralkyl group, According to the objective, it can select suitably, For example, a benzyl group, a phenylethyl group, a phenylpropyl group, etc. are mentioned.
There is no restriction | limiting in particular as said aryl group, According to the objective, it can select suitably, A C6-C15 thing is preferable, for example, a phenyl group, a tolyl group, a xylyl group, a biphenylyl group, a naphthyl group, anthryl. Group, phenanthryl group, and the like.
As said alkoxy group, a C1-C10 thing is preferable, for example, a methoxy group, an ethoxy group, a propoxy group, a butoxy group etc. are mentioned.

In the structural formulas (II) and (III), R ^{3 to} R ⁵ may be the same as or different from each other, and represent a divalent hydrocarbon group. As the divalent hydrocarbon group, those similar to the above R ¹ can be used, and an alkylene group having 1 to 20 carbon atoms, an arylene group having 6 to 15 carbon atoms and the like are preferable.
Ar represents a trivalent aromatic hydrocarbon group, and examples thereof include those obtained by removing two hydrogen atoms from an aryl group.
R ^{1 to} R ⁵ and Ar may be further substituted with a substituent, and two or three adjacent R ² , R ³ , R ⁴ and R ⁵ may be linked to form a ring. Examples of the ring include an aromatic ring, an aliphatic ring, and a heterocyclic ring.

  Specific examples of the diisocyanate compound represented by the structural formula (I) include 2,4-tolylene diisocyanate, dimer of 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p- Aromatic diisocyanate compounds such as xylylene diisocyanate, metaxylylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3′-dimethyl-biphenyl-4,4′-diisocyanate; hexamethylene diisocyanate Aliphatic diisocyanate compounds such as trimethylhexamethylene diisocyanate, lysine diisocyanate and dimer acid diisocyanate; isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate), methylcyclohexane Alicyclic diisocyanate compounds such as sun-2,4 (or 2,6) diisocyanate, 1,3- (isocyanatomethyl) cyclohexane; adducts of 1 mol of 1,3-butylene glycol and 2 mol of tolylene diisocyanate, etc. Examples thereof include a diisocyanate compound which is a reaction product of a diol compound and a diisocyanate compound. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the diol compound having a carboxyl group represented by the structural formula (II) or the structural formula (III) include 3,5-dihydroxybenzoic acid, 2,2-bis (hydroxymethyl) propionic acid, 2-bis (hydroxyethyl) propionic acid, 2,2-bis (3-hydroxypropyl) propionic acid, 2,2-bis (hydroxymethyl) acetic acid, bis- (4-hydroxyphenyl) acetic acid, 4,4-bis -(4-hydroxyphenyl) pentanoic acid, tartaric acid and the like. These may be used individually by 1 type and may use 2 or more types together.

The polyurethane resin is composed of two or more kinds of diisocyanate compounds represented by the structural formula (I) and diol compounds having a carboxyl group represented by the structural formula (II) or the structural formula (III). It may be formed.
Moreover, the diol compound which does not have a carboxyl group and may have the substituent which does not react with another isocyanate compound can be used together to such an extent that alkali developability is not reduced. 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-butylene glycol, and 1,6-hexanediol. 2-butene-1,4-diol, 2,2,4-trimethyl-1,3-pentanediol, 1,4-bis-β-hydroxyethoxycyclohexane, cyclohexanedimethanol, tricyclodecanedimethanol, hydrogenated Bisphenol A, hydrogenated bisphenol F, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, ethylene oxide adduct of bisphenol F, bisphenol Propylene oxide adduct of hydrogen F, ethylene oxide adduct of hydrogenated bisphenol A, propylene oxide adduct of hydrogenated bisphenol A, hydroquinone dihydroxyethyl ether, p-xylylene glycol, dihydroxyethyl sulfone, bis- (2-hydroxyethyl) ) 2,4-tolylene dicarbamate, 2,4-tolylene-bis- (2-hydroxyethylcarbamide), bis- (2-hydroxyethyl) m-xylylenecarbamate, bis- (2-hydroxyethyl) phthalate, etc. Can be mentioned. These may be used individually by 1 type and may use 2 or more types together.

The polyurethane resin can be synthesized by adding and heating the diisocyanate compound and the diol compound in an aprotic solvent according to the reactivity of each known active catalyst.
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 an isocyanate group remains at the terminal of the polyurethane resin, it is synthesized by treating with alcohols or amines so that no isocyanate group remains finally.

The acid value of the polyurethane resin as the component (A) is preferably 80 to 300 mgKOH / g, more preferably 80 to 180 mgKOH / g, still more preferably 90 to 170 mgKOH / g, and particularly preferably 100 to 160 mgKOH / g. If the acid value is less than 80 mgKOH / g, the resulting photosensitive composition may not exhibit excellent alkali developability, and if it exceeds 300 mgKOH / g, the shape of the pattern from the resulting photosensitive composition may be Deteriorating and high resolution may not be obtained.
Here, the acid value can be calculated from a neutralized amount obtained by dissolving a certain amount of polyurethane carboxylic acid in a solvent such as methoxypropanol and titrating with a potassium hydroxide aqueous solution having a known titer. it can.

1000 or more are preferable and, as for the weight average molecular weight (Mw) in the polyurethane resin which has the said carboxyl group, 5000-100,000 are more preferable.
50-99.5 mass% is preferable with respect to the said photosensitive composition, and, as for content of the polyurethane resin which has the said carboxyl group, 55-95 mass% is more preferable. When the content of the polyurethane resin is less than 50% by mass, the object and effect of the present invention may not be achieved. When the content is too large, the amount of the polymerizable compound is relatively reduced. The alkali developer resistance, the mechanical strength of the cured film and the solder heat resistance may deteriorate.

  In addition to the polyurethane resin, it is preferable to add another resin to the photosensitive composition of the present invention in an amount of 50% by mass or less based on the polyurethane resin as necessary. Examples of the other resin include polyamide resin, epoxy resin, polyacetal resin, acrylic resin, methacrylic resin, polystyrene resin, and novolac type phenol resin.

[(B) Polymerizable compound]
The polymerizable compound is not particularly limited and may be appropriately selected depending on the intended purpose. However, the polymerizable compound has at least one, preferably two or more addition-polymerizable groups in the molecule, and has a normal boiling point. The compound which is 100 degreeC or more is preferable, for example, at least 1 sort (s) selected from the monomer which has a (meth) acryl group is mentioned suitably.

  There is no restriction | limiting in particular as a monomer which has the said (meth) acryl group, According to the objective, it can select suitably, For example, polyethyleneglycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, phenoxyethyl (meth) ) Monofunctional acrylates and monofunctional methacrylates such as acrylates; polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, trimethylolpropane diacrylate, neopentylglycol di (Meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, dipentaerythritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanurate, tri (acryloyloxyethyl) cyanurate, glycerin Poly (functional) alcohols such as tri (meth) acrylate, trimethylolpropane, glycerin, bisphenol, etc., which are subjected to addition reaction with ethylene oxide and propylene oxide, and converted to (meth) acrylate, Japanese Patent Publication No. 48-41708, Japanese Patent Publication No. 50- Urethane acrylates described in JP-A-6034, JP-A-51-37193, etc .; JP-A-48-64183, JP-B-49-43191, JP-B-52-30 Polyester acrylates described in each publication of such 90 No.; and epoxy resin and (meth) polyfunctional acrylates or methacrylates such as epoxy acrylates which are reaction products of acrylic acid. Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta (meth) acrylate are particularly preferable.

  5-50 mass% is preferable and, as for solid content in the said photosensitive composition solid content of the said polymeric compound, 10-40 mass% is more preferable. If the solid content is less than 5% by mass, problems such as deterioration of developability and reduction in exposure sensitivity may occur, and if it exceeds 50% by mass, the adhesiveness of the photosensitive layer may become too strong. Yes, not preferred.

[(C) Photopolymerization initiator]
The photopolymerization initiator is not particularly limited as long as it has the ability to initiate polymerization of the polymerizable compound, and can be appropriately selected from known photopolymerization initiators. For example, it is visible from the ultraviolet region. It is preferable to have photosensitivity to the light, and it may be an activator that produces some kind of action with a photoexcited sensitizer and generates active radicals, and initiates cationic polymerization depending on the type of monomer. Initiator may be used.
The photopolymerization initiator preferably contains at least one component having a molecular extinction coefficient of at least about 50 within a range of about 300 to 800 nm (more preferably 330 to 500 nm).

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

  Examples of the halogenated hydrocarbon compound having a triazine skeleton include those described in Wakabayashi et al., Bull. Chem. Soc. Japan, 42, 2924 (1969), a compound described in British Patent No. 1388492, a compound described in JP-A-53-133428, a compound described in German Patent No. 3333724, F.I. C. J. Schaefer et al. Org. Chem. 29, 1527 (1964), compounds described in JP-A-62-258241, compounds described in JP-A-5-281728, compounds described in JP-A-5-34920, US Pat. No. 4,221,976 And the compounds described in the book.

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

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

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

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

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

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

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

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

  Examples of the oxime derivative include 3-benzoyloxyiminobutan-2-one, 3-acetoxyiminobutane-2-one, 3-propionyloxyiminobutan-2-one, and 2-acetoxyiminopentane-3-one. 2-acetoxyimino-1-phenylpropan-1-one, 2-benzoyloxyimino-1-phenylpropan-1-one, 3- (4-toluenesulfonyloxy) iminobutan-2-one, and 2-ethoxy And carbonyloxyimino-1-phenylpropan-1-one.

  Further, as photopolymerization initiators other than the above, acridine derivatives (for example, 9-phenylacridine, 1,7-bis (9,9′-acridinyl) heptane, etc.), N-phenylglycine, and the like, polyhalogen compounds (for example, Carbon tetrabromide, phenyltribromomethylsulfone, phenyltrichloromethylketone, etc.), coumarins (for example, 3- (2-benzofuroyl) -7-diethylaminocoumarin, 3- (2-benzofuroyl) -7- (1-pyrrolidinyl) ) Coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-methoxybenzoyl) -7-diethylaminocoumarin, 3- (4-dimethylaminobenzoyl) -7-diethylaminocoumarin, 3,3′-carbonylbis (5 , 7-di-n-propoxycoumarin), 3,3′-carbonylbis (7-diethylaminocoumarin), 3-benzoyl-7-methoxycoumarin, 3- (2-furoyl) -7-diethylaminocoumarin, 3- (4-diethylaminocinnamoyl) -7-diethylaminocoumarin, 7-methoxy-3- (3-pyridylcarbonyl) coumarin, 3-benzoyl-5,7-dipropoxycoumarin, 7-benzotriazol-2-ylcoumarin, JP-A-5-19475, JP-A-7-271028, JP-A-2002-363206 No., JP-A-2002-363207, JP-A-2002-363208, JP-A-2002-363209, etc.), amines (for example, ethyl 4-dimethylaminobenzoate, 4-dimethylaminobenzoate) N-butyl acid, 4-dimethylaminobenzoic acid phenethyl, 4-dimethyl 2-phthalimidoethyl tilaminobenzoate, 2-methacryloyloxyethyl 4-dimethylaminobenzoate, pentamethylenebis (4-dimethylaminobenzoate), phenethyl of 3-dimethylaminobenzoic acid, pentamethylene ester, 4-dimethylaminobenzaldehyde, 2-chloro-4-dimethylaminobenzaldehyde, 4-dimethylaminobenzyl alcohol, ethyl (4-dimethylaminobenzoyl) acetate, 4-piperidinoacetophenone, 4-dimethylaminobenzoin, N, N-dimethyl-4-toluidine, N, N-diethyl-3-phenetidine, tribenzylamine, dibenzylphenylamine, N-methyl-N-phenylbenzylamine, 4-bromo-N, N-dimethylaniline, tridodecylamine, amino Nofluoranes (ODB, ODBII, etc.), crystal violet lactone, leuco crystal violet, etc., acylphosphine oxides (for example, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) ) -2,4,4-trimethyl-pentylphenylphosphine oxide, Lucirin TPO, etc.), metallocenes (for example, bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3-) (1H-pyrrol-1-yl) -phenyl) titanium, η5-cyclopentadienyl-η6-cumenyl-iron (1 +)-hexafluorophosphate (1-), etc.), JP-A-53-133428, Kosho 57-1819, 57-609 JP, and include compounds described in U.S. Patent No. 3,615,455.

  Examples of the ketone compound include benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 4-methoxybenzophenone, 2-chlorobenzophenone, 4-chlorobenzophenone, 4-bromobenzophenone, 2-carboxybenzophenone, 2-ethoxycarbonylbenzolphenone, benzophenonetetracarboxylic acid or tetramethyl ester thereof, 4,4′-bis (dialkylamino) benzophenone (for example, 4,4′-bis (dimethylamino) benzophenone, 4,4′- Bisdicyclohexylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, 4,4′-bis (dihydroxyethylamino) benzophenone, 4-methoxy-4′-dimethylamino Nzophenone, 4,4'-dimethoxybenzophenone, 4-dimethylaminobenzophenone, 4-dimethylaminoacetophenone, benzyl, anthraquinone, 2-t-butylanthraquinone, 2-methylanthraquinone, phenanthraquinone, xanthone, thioxanthone, 2-chloro -Thioxanthone, 2,4-diethylthioxanthone, fluorenone, 2-benzyl-dimethylamino-1- (4-morpholinophenyl) -1-butanone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino -1-propanone, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer, benzoin, benzoin ethers (for example, benzoin methyl ether, benzoin ethyl ether, In propyl ether, benzoin isopropyl ether, benzoin phenyl ether, benzyl dimethyl ketal), acridone, chloro acridone, N- methyl acridone, N- butyl acridone, N- butyl - such as chloro acrylic pyrrolidone.

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

  The sensitizer is not particularly limited and may be appropriately selected from known sensitizers. For example, known polynuclear aromatics (for example, pyrene, perylene, triphenylene), xanthenes (for example, , Fluorescein, eosin, erythrosine, rhodamine B, rose bengal), cyanines (eg, indocarbocyanine, thiacarbocyanine, oxacarbocyanine), merocyanines (eg, merocyanine, carbomerocyanine), thiazines (eg, thionine, Methylene blue, toluidine blue), acridines (eg, acridine orange, chloroflavin, acriflavine), anthraquinones (eg, anthraquinone), squariums (eg, squalium), acridones (eg, acridone, chloroacrine) Don, N-methylacridone, N-butylacridone, N-butyl-chloroacridone, etc.), coumarins (for example, 3- (2-benzofuroyl) -7-diethylaminocoumarin, 3- (2-benzofuroyl)- 7- (1-pyrrolidinyl) coumarin, 3-benzoyl-7-diethylaminocoumarin, 3- (2-methoxybenzoyl) -7-diethylaminocoumarin, 3- (4-dimethylaminobenzoyl) -7-diethylaminocoumarin, 3,3 '-Carbonylbis (5,7-di-n-propoxycoumarin), 3,3'-carbonylbis (7-diethylaminocoumarin), 3-benzoyl-7-methoxycoumarin, 3- (2-furoyl) -7- Diethylaminocoumarin, 3- (4-diethylaminocinnamoyl) -7-diethylaminocoumarin Examples thereof include 7-methoxy-3- (3-pyridylcarbonyl) coumarin, 3-benzoyl-5,7-dipropoxycoumarin, and others, and JP-A-5-19475, JP-A-7-271028, JP-A-2002-. No. 363206, JP-A No. 2002-363207, JP-A No. 2002-363208, JP-A No. 2002-363209, and the like.

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

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

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

  As content in the said photosensitive composition of the said photoinitiator, 0.1-30 mass% is preferable, 0.5-20 mass% is more preferable, 0.5-15 mass% is especially preferable.

(Thermal crosslinking agent)
The thermal crosslinking agent is not particularly limited and may be appropriately selected depending on the purpose. In order to improve the film strength after curing of the photosensitive layer formed using the photosensitive composition, developability For example, at least one selected from an epoxy resin compound, an oxetane compound, a polyisocyanate compound, a compound obtained by reacting a polyisocyanate compound with a blocking agent, and a melamine derivative may be used. it can.

  Examples of the epoxy resin compound include a bixylenol type or biphenol type epoxy resin (“YX4000, manufactured by Japan Epoxy Resin Co., Ltd.”) or a mixture thereof, a heterocyclic epoxy resin having an isocyanurate skeleton (“TEPIC, Nissan”). Chemical Industries, "Araldite PT810, Ciba Specialty Chemicals, etc.), bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, glycidyl amine type epoxy resin, Hydantoin type epoxy resin, alicyclic epoxy resin, trihydroxyphenylmethane type epoxy resin, bisphenol S type epoxy resin, bisphenol A novolac type epoxy resin, tetraphenylolethane type Poxy resin, glycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, naphthalene group-containing epoxy resin (“ESN-190, ESN-360, manufactured by Nippon Steel Chemical Co., Ltd.”, “HP-4032, EXA-4750, EXA-4700; large Nippon Ink Chemical Co., Ltd. ”), epoxy resins having a dicyclopentadiene skeleton (“ HP-7200, HP-7200H; manufactured by Dainippon Ink & Chemicals ”etc.), glycidyl methacrylate copolymer epoxy resin (“ CP -50S, CP-50M; manufactured by NOF Corporation, etc.), a copolymer epoxy resin of cyclohexylmaleimide and glycidyl methacrylate, and the like, but is not limited thereto. These epoxy resins may be used individually by 1 type, and may use 2 or more types together.

  Examples of the oxetane compound include 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, (3-methyl-3-oxetanyl) methyl acrylate, (3-ethyl-3-oxetanyl) In addition to polyfunctional oxetanes such as methyl acrylate, (3-methyl-3-oxetanyl) methyl methacrylate, (3-ethyl-3-oxetanyl) methyl methacrylate or oligomers or copolymers thereof, oxetane groups and novolak resins , Poly (p-hydroxystyrene), cardo-type bisphe And ether compounds with hydroxyl groups, such as siloles, calixarenes, calixresorcinarenes, silsesquioxanes, and the like, as well as unsaturated monomers having an oxetane ring and alkyl (meth) acrylates. And a copolymer thereof.

Moreover, in order to accelerate the thermal curing of the epoxy resin compound or the oxetane compound, for example, dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N-dimethyl Amine compounds such as benzylamine and 4-methyl-N, N-dimethylbenzylamine; quaternary ammonium salt compounds such as triethylbenzylammonium chloride; blocked isocyanate compounds such as dimethylamine; imidazole, 2-methylimidazole and 2-ethylimidazole , 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole, etc. Bicyclic amidine compounds and salts thereof; phosphorus compounds such as triphenylphosphine; guanamine compounds such as melamine, guanamine, acetoguanamine and benzoguanamine; 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2 -Vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine isocyanuric acid adduct, 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid S-triazine derivatives such as adducts can be used. These may be used alone or in combination of two or more. The epoxy resin compound or the oxetane compound is a curing catalyst, or any compound that can accelerate the reaction between the epoxy resin compound and the oxetane compound and a carboxyl group. May be.
Solid content in the said photosensitive composition solid content of the said epoxy resin, the said oxetane compound, and the compound which can accelerate | stimulate thermosetting with these and carboxylic acid is 0.01-15 mass% normally.

  Further, as the thermal crosslinking agent, a polyisocyanate compound described in JP-A-5-9407 can be used, and the polyisocyanate compound is aliphatic, cycloaliphatic or aromatic containing at least two isocyanate groups. It may be derived from a group-substituted aliphatic compound. Specifically, a mixture of 1,3-phenylene diisocyanate and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate, 1,3- and 1,4-xylylene diisocyanate, bis (4 -Isocyanate-phenyl) methane, bis (4-isocyanatocyclohexyl) methane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc .; bifunctional isocyanates, trimethylolpropane, pentalysitol, glycerin, etc. An alkylene oxide adduct of the polyfunctional alcohol and an adduct of the bifunctional isocyanate; hexamethylene diisocyanate, hexamethylene-1,6-diisocyanate Cyclic trimers, such as preparative and derivatives thereof; and the like.

Furthermore, for the purpose of improving 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 and its derivative may be used.
Examples of the isocyanate group blocking agent include isopropanol, tert. Alcohols such as butanol; lactams such as ε-caprolactam; phenol, cresol, p-tert. -Butylphenol, p-sec. -Butylphenol, p-sec. -Phenols such as amylphenol, p-octylphenol, p-nonylphenol; heterocyclic hydroxyl compounds such as 3-hydroxypyridine and 8-hydroxyquinoline; dialkylmalonate, methylethylketoxime, acetylacetone, alkylacetoacetate oxime, acetoxime, Active methylene compounds such as cyclohexanone oxime; and the like. In addition to these, compounds having at least one polymerizable double bond and at least one blocked isocyanate group in the molecule described in JP-A-6-295060 can be used.

  Moreover, a melamine derivative can be used as the thermal crosslinking agent. Examples of the melamine derivative include methylol melamine, alkylated methylol melamine (a compound obtained by etherifying a methylol group with methyl, ethyl, butyl or the like). These may be used individually by 1 type and may use 2 or more types together. Among these, alkylated methylol melamine is preferable and hexamethylated methylol melamine is particularly preferable in that it has good storage stability and is effective in improving the surface hardness of the photosensitive layer or the film strength itself of the cured film.

  1-40 mass% is preferable and, as for solid content in the said photosensitive composition solid content of the said thermal crosslinking agent, 3-20 mass% is more preferable. When the solid content is less than 1% by mass, improvement in the film strength of the cured film is not recognized, and when it exceeds 40% by mass, the developability and the exposure sensitivity may be lowered.

[Other ingredients]
Examples of the other components include thermal polymerization inhibitors, plasticizers, colorants (color pigments or dyes), extender pigments, and the like, and further adhesion promoters to the substrate surface and other auxiliary agents ( For example, conductive particles, fillers, antifoaming agents, flame retardants, leveling agents, peeling accelerators, antioxidants, fragrances, surface tension modifiers, chain transfer agents, etc.) may be used in combination. By appropriately containing these components, properties such as stability, photographic properties, and film properties of the intended photosensitive composition can be adjusted.

-Thermal polymerization inhibitor-
The thermal polymerization inhibitor may be added to prevent thermal polymerization or temporal polymerization 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-tert-butyl-4-cresol, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), pyridine, nitrobenzene, dinitrobenzene, picric acid 4-toluidine, methylene blue, copper and organic chelating agent reactant, methyl salicylate, phenothiazine, nitroso compound, chelate of nitroso compound and Al, and the like.

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

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

  The solid content in the photosensitive composition solid content of the color pigment can be determined in consideration of the exposure sensitivity, resolution, etc. of the photosensitive layer at the time of permanent pattern formation, depending on the type of the color pigment. Generally, 0.05 to 10% by mass is preferable, and 0.1 to 5% by mass is more preferable.

-Extender pigment-
If necessary, the photosensitive composition may be inorganic for the purpose of improving the surface hardness of the permanent pattern or keeping the linear expansion coefficient low, or keeping the dielectric constant or dielectric loss tangent of the cured film itself low. Pigments and organic fine particles can be added.
The inorganic pigment is not particularly limited and may be appropriately selected from known ones. For example, kaolin, barium sulfate, barium titanate, silicon oxide powder, finely divided silicon oxide, vapor phase method silica, amorphous Examples thereof include silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica.
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 scattering.
There is no restriction | limiting in particular as said organic fine particle, According to the objective, it can select suitably, For example, a melamine resin, a benzoguanamine resin, a crosslinked polystyrene resin etc. are mentioned. Further, silica having an average particle diameter of 1 to 5 μm and an oil absorption of about 100 to 200 m ² / g, spherical porous fine particles made of a crosslinked resin, and the like can be used.

  The amount of the extender is preferably 5 to 60% by mass. When the addition amount is less than 5% by mass, the linear expansion coefficient may not be sufficiently reduced. When the addition amount exceeds 60% by mass, when the cured film is formed on the photosensitive layer surface, The film quality becomes fragile, and when a wiring is formed using a permanent pattern, the function of the wiring as a protective film may be impaired.

-Adhesion promoter-
In order to improve the adhesion between the layers or the adhesion between the photosensitive layer and the substrate, a known so-called adhesion promoter can be used for each layer.

  Suitable examples of the adhesion promoter include adhesion promoters described in JP-A-5-11439, JP-A-5-341532, and JP-A-6-43638. Specifically, benzimidazole, benzoxazole, benzthiazole, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzthiazole, 3-morpholinomethyl-1-phenyl-triazole-2-thione, 3-morpholino Methyl-5-phenyl-oxadiazole-2-thione, 5-amino-3-morpholinomethyl-thiadiazole-2-thione, and 2-mercapto-5-methylthio-thiadiazole, triazole, tetrazole, benzotriazole, carboxybenzotriazole Amino group-containing benzotriazole, silane coupling agents, and the like.

  As content of the said adhesion promoter, 0.001 mass%-20 mass% are preferable with respect to all the components in the said photosensitive composition, 0.01-10 mass% is more preferable, 0.1 mass% ˜5% by weight is particularly preferred.

  The photosensitive composition of the present invention is excellent in developability, solder heat resistance, folding resistance and pressure cooker resistance, and the flexibility of the cured film is greatly improved. For this reason, it is widely used for the formation of permanent patterns such as printed wiring boards (multilayer wiring boards, build-up wiring boards, etc.), color filters, pillar materials, rib materials, spacers, partition walls, and other display members, holograms, micromachines, and proofs. In particular, it can be suitably used for the photosensitive composition, permanent pattern and method of forming the same of the present invention.

(Photosensitive layer)
The photosensitive layer is formed by the photosensitive composition of the present invention.
In the exposure process described later, the photosensitive layer modulates the light from the light irradiating means after modulating the light from the light irradiating means by light modulating means having at least n image elements for receiving and emitting light from the light irradiating means. Lens aperture shape that does not allow light that has passed through a microlens array in which microlenses having aspherical surfaces capable of correcting aberration due to distortion of the exit surface in the element part to be incident or light from the peripheral part of the picture element part are not incident It is preferable that the exposure is performed with the light that has passed through the microlens array in which microlenses having the structure are arranged.

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

  As the method for forming the photosensitive layer, a photosensitive composition solution is prepared by dissolving, emulsifying, or dispersing the photosensitive composition of the present invention in water or a solvent on a substrate, and directly applying the solution. And a method of laminating by drying.

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

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

(Permanent pattern and pattern forming method)
The permanent pattern of the present invention is obtained by the pattern forming method of the present invention.
In the pattern forming method of the present invention, the photosensitive composition of the present invention is applied to the surface of a substrate, dried to form a photosensitive layer, and then exposed and developed. In the present invention, since a photosensitive composition excellent in flexibility and folding resistance is used, it can be applied to a flexible substrate, can be exposed in a roll-to-roll manner, and the productivity is dramatically improved. To improve.
Hereinafter, the details of the permanent pattern of the present invention will be clarified through the description of the pattern forming method of the present invention.

〔Base material〕
There is no restriction | limiting in particular as said base material, From the well-known material, what has high surface smoothness to what has an uneven surface can be selected suitably, for example, a plate-shaped base material (board | substrate) is. Preferably, specific examples include a flexible printed wiring board forming substrate (for example, a copper-clad laminate), a glass plate (for example, a soda glass plate), a synthetic resin film, paper, a metal plate, and the like. Among these, a flexible printed wiring board forming substrate is preferable, and the printed wiring board forming substrate has already been formed in terms of enabling high-density mounting of a semiconductor or the like on a multilayer wiring board or a build-up wiring board. Is particularly preferred.

  The base material is cured by exposing the photosensitive layer in the laminate in which a photosensitive layer made of the photosensitive composition is formed on the base material to be described later, thereby curing the exposed region. A permanent pattern can be formed.

-Laminate-
There is no restriction | limiting in particular as a formation method of the said laminated body, Although it can select suitably according to the objective, The photosensitive layer formed by apply | coating and drying the said photosensitive composition on the said base material is laminated | stacked. Is preferred.
There is no restriction | limiting in particular as the method of the said application | coating and drying, According to the objective, it can select suitably, For example, the said photosensitive composition solution performed when forming the photosensitive layer in the said photosensitive composition is used. For example, a method of applying the photosensitive composition solution by using a spin coater, a slit spin coater, a roll coater, a die coater, a curtain coater or the like can be used.

[Exposure process]
In the exposure step, the light from the light irradiating means is modulated by the light modulating means having at least n picture elements for receiving and emitting the light from the light irradiating means, and then the emission surface of the picture element portion. A microlens having a lens opening shape that does not allow light that has passed through a microlens array in which microlenses having an aspheric surface capable of correcting aberration due to distortion of the lens to be arranged, or light from a peripheral portion of the pixel portion to be incident. In this step, the photosensitive layer formed in the photosensitive layer forming step is exposed to light that has passed through the arrayed microlens array.

  In the exposure step, the light from the light irradiating means is modulated by the light modulating means having at least n picture elements for receiving and emitting the light from the light irradiating means, and then the emission surface of the picture element portion. A microlens having a lens opening shape that does not allow light that has passed through a microlens array in which microlenses having an aspheric surface capable of correcting aberration due to distortion of the lens to be arranged, or light from a peripheral portion of the pixel portion to be incident. A step of exposing the photosensitive layer formed by the photosensitive layer forming step with light transmitted through the arrayed microlens array.

In the exposure step, the light emitted from the light irradiation means is not particularly limited and can be appropriately selected according to the purpose. For example, an electromagnetic wave that activates a photopolymerization initiator and a sensitizer, Examples include ultraviolet to visible light, electron beams, X-rays, and laser beams. Among these, laser beams that can perform on / off control of light in a short time and easily control light interference are preferable.
There is no restriction | limiting in particular as a wavelength of the light of the said ultraviolet to visible light, Although it can select suitably according to the objective, 330-650 nm is preferable and the objective of shortening the exposure time of a photosensitive composition is 395. ˜415 nm is more preferable, and 405 nm is particularly preferable.
The light irradiation method by the light irradiation means is not particularly limited and can be appropriately selected according to the purpose. For example, a high pressure mercury lamp, a xenon lamp, a carbon arc lamp, a halogen lamp, a cold cathode tube for a copying machine, The method of irradiating with well-known light sources, such as LED and a semiconductor laser, is mentioned. In addition, it is preferable that two or more light beams from these light sources are combined and irradiated, and laser light that combines two or more light beams (hereinafter, referred to as “combined laser beam”) is irradiated. Is particularly preferred.
There is no restriction | limiting in particular as the irradiation method of the said combined laser beam, Although it can select suitably according to the objective, A laser irradiated from a several laser light source, a multimode optical fiber, and this several laser light source There is a method of forming and irradiating a combined laser beam with a collective optical system that collects light and couples it to the multimode optical fiber.

In the exposure step, the method of modulating light is not particularly limited as long as it is a method of modulating light by means of light modulating means having n picture elements for receiving and emitting light from the light irradiating means. Depending on the pattern information, a method of suitably controlling any less than n pixel portions arranged continuously from n pixel portions can be preferably used.
There is no restriction | limiting in particular as the number (n) of said picture element parts, Although it can select suitably according to the objective, Two or more are preferable.
The arrangement of the picture element portions in the light modulation means is not particularly limited and may be appropriately selected according to the purpose. For example, it is preferably arranged two-dimensionally and arranged in a lattice pattern. Is more preferable.
The light modulation method is not particularly limited and may be appropriately selected depending on the intended purpose. A preferable example is a method in which the light modulation means uses a spatial light modulation element.
The spatial light modulation element is not particularly limited and may be appropriately selected depending on the intended purpose. However, a digital micromirror device (DMD) or a MEMS (Micro Electro Mechanical Systems) type spatial light modulation element (SLM) may be used. A Special Light Modulator), an optical element that modulates transmitted light by an electro-optic effect (PLZT element), a liquid crystal light shutter (FLC), and the like. Among these, a DMD is particularly preferable.

In the exposure step, the light modulated by the modulation means is a microlens array in which microlenses having aspherical surfaces capable of correcting aberrations due to distortion of the exit surface in the imager unit, or the imager unit Can be passed through a microlens array in which microlenses having a lens aperture shape that does not allow light from the periphery of the lens to enter.
Although there is no restriction | limiting in particular as a microlens arrange | positioned at the said microlens array, For example, what has an aspherical surface is preferable, and it is more preferable that the said aspherical surface is a microlens which is a toric surface.
Further, in the exposure step, it is preferable that the light modulated by the modulation means is allowed to pass through an aperture array, a coupling optical system, other optical systems appropriately selected, and 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 intended purpose. Examples thereof include digital exposure and analog exposure, but digital exposure is preferred. .
The digital exposure method is not particularly limited and may be appropriately selected depending on the purpose. For example, the digital exposure method is performed using laser light modulated according to a control signal generated based on predetermined pattern information. Is preferred.
Furthermore, in the exposure step, the method for exposing the photosensitive layer is not particularly limited and can be appropriately selected according to the purpose. From the viewpoint of enabling high-speed exposure in a short time, It is preferably carried out while relatively moving the photosensitive layer, and particularly preferably used in combination with the digital micromirror device (DMD).

In the exposure step, exposure can be performed in an inert gas atmosphere. For example, the method for exposing the photosensitive layer formed by the photosensitive layer forming step is not particularly limited and can be appropriately selected according to the purpose. For example, an inert gas is sprayed directly on the surface of the photosensitive layer. Method, placing a sample on which a photosensitive layer to be exposed is placed in an exposure space in a sample stage in which one side of a frame-shaped frame is opened and an inert gas introduction hole is formed on at least one remaining side, Examples thereof include a method of performing exposure while introducing an inert gas from the inert gas introduction hole and covering the surface of the photosensitive layer with the inert gas.
In addition, it is possible to introduce an inert gas into the sealed space under reduced pressure using the exposure space as a sealed space.
The inert gas is not particularly limited as long as it can prevent the polymerization reaction of the photosensitive layer from being inhibited by the influence of oxygen, and can be appropriately selected according to the purpose. For example, nitrogen, helium, argon, etc. Is mentioned.

  Hereinafter, a pattern forming apparatus suitably used in the pattern forming method of the present invention will be described with reference to the drawings.

FIG. 7 is a schematic perspective view showing an appearance of a pattern forming apparatus suitably used in the pattern forming method of the present invention.
As shown in FIG. 7, the pattern forming apparatus including the light modulating means adsorbs the sheet-like pattern forming material 150 on the upper surface of a thick plate-like installation table 156 supported by four legs 154. A flat plate-like stage 152 is provided.
The stage 152 is arranged so that the longitudinal direction thereof faces the stage moving direction, and is supported by a guide 158 formed on the upper surface of the installation table 156 so as to be reciprocally movable. The pattern forming apparatus has a drive device (not shown) for driving the stage 152 along the guide 158.

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

FIG. 8 is a schematic perspective view showing the configuration of the scanner. FIG. 9A is a plan view showing an exposed area formed on the photosensitive layer, and FIG. 9B is a view showing an arrangement of exposure areas by the exposure head.
As shown in FIGS. 8 and 9B, the scanner 162 includes a plurality of (for example, 14) exposure heads 166 arranged in a substantially matrix of m rows and n columns (for example, 3 rows and 5 columns). In this example, four exposure heads 166 are arranged in the third row in relation to the width of the pattern forming material 150. In addition, when showing each exposure head arranged in the m-th row and the n-th column, it is expressed as an exposure head 166 _mn .
An exposure area 168 by the exposure head 166 has a rectangular shape with a short side in the sub-scanning direction. Accordingly, as the stage 152 moves, a strip-shaped exposed region 170 is formed in the pattern forming material 150 for each exposure head 166. In addition, when showing the exposure area by each exposure head arranged in the m-th row and the n-th column, it is expressed as an exposure area 168 _mn .

Further, as shown in FIGS. 9A and 9B, each of the exposure heads in each row arranged in a line is arranged in a predetermined direction in the arrangement direction so that the strip-shaped exposed areas 170 are arranged without gaps in the direction orthogonal to the sub-scanning direction. They are arranged with a gap (natural number times the long side of the exposure area, twice in this example). Therefore, can not be exposed portion between the exposure area _{168 11} in the first row and the exposure area _{168 12,} it can be exposed by the second row of the exposure area _{168 21} and the exposure area _{168 31} in the third row.

FIG. 10 is a perspective view showing a schematic configuration of the exposure head.
As shown in FIG. 10, each of the exposure heads 166 _{11 to} 166 _mn serves as the light modulation means (spatial light modulation element for modulating each pixel) that modulates a light beam according to pattern information. A digital micromirror device (hereinafter also referred to as “DMD”) 50 manufactured by Instruments Co., Ltd. A fiber array light source 66 as a light irradiating means 66 provided with laser emitting portions 68 arranged in a line along a direction corresponding to the side direction, and a laser beam emitted from the fiber array light source 66 are corrected and placed on the DMD. A lens system 67 for condensing, a mirror 69 for reflecting laser light transmitted through the lens system 67 toward the DMD 50, and a laser reflected by the DMD 50 The B, and an image forming optical system 51 forms an image on the pattern forming material 150. In FIG. 10, the lens system 67 is schematically shown.

FIG. 12 shows a controller that controls the DMD based on the pattern information.
As shown in FIG. 12, the DMD 50 is connected to a controller 302 having a data processing unit, a mirror drive control unit, and the like. The data processing unit of the controller 302 generates a control signal for driving and controlling each micromirror in the region to be controlled by the DMD 50 for each exposure head 166 based on the input pattern information. The area to be controlled will be described later. The mirror drive control unit controls the angle of the reflection surface of each micromirror of the DMD 50 for each exposure head 166 based on the control signal generated by the pattern information processing unit.

FIG. 1 is a partially enlarged view showing a configuration of a digital micromirror device (DMD) as the light modulation means.
As shown in FIG. 1, in the DMD 50, a large number (for example, 1024 × 768) of micromirrors (micromirrors) 62 each constituting a pixel (pixel) are arranged on a SRAM cell (memory cell) 60 in a lattice shape. This is a mirror device arranged in a row. In each pixel, a micromirror 62 supported by a support column is provided at the top, and a material having high reflectivity such as aluminum is deposited on the surface of the micromirror 62. The reflectance of the micromirror 62 is 90% or more, and the arrangement pitch is 13.7 μm as an example in both the vertical and horizontal directions. A silicon gate CMOS SRAM cell 60 manufactured in a normal semiconductor memory manufacturing line is disposed directly below the micromirror 62 via a support including a hinge and a yoke. The entire structure is monolithically configured. ing.

2A and 2B are diagrams for explaining the operation of the DMD.
When a digital signal is written in the SRAM cell 60 of the DMD 50, the micromirror 62 supported by the support is tilted in a range of ± α degrees (for example, ± 12 degrees) with respect to the substrate side on which the DMD 50 is disposed with the diagonal line as the center. It is done. 2A shows a state in which the micromirror 62 is tilted to + α degrees when the micromirror 62 is in an on state, and FIG. 2B shows a state in which the micromirror 62 is tilted to −α degrees that is in an off state.
Therefore, by controlling the tilt of the micromirror 62 in each pixel of the DMD 50 according to the pattern information, the laser light incident on the DMD 50 is reflected in the tilt 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. On / off control of each micromirror 62 is performed by the controller 302 connected to the DMD 50. A light absorber (not shown) is arranged in the direction in which the laser beam B reflected by the micromirror 62 in the off state travels.

The DMD 50 is preferably arranged with a slight inclination so that the short side forms a predetermined angle θ (for example, 0.1 ° to 5 °) with the sub-scanning direction.
3A shows the scanning trajectory of the reflected light image (exposure beam) 53 by each micromirror when the DMD 50 is not tilted, and FIG. 3B shows the scanning trajectory of the exposure beam 53 when the DMD 50 is tilted.
As shown in FIG. 3B, in the DMD 50, a number of micromirror arrays in which a large number (for example, 1024) of micromirrors are arranged in the longitudinal direction are arranged in a short direction (for example, 756 sets). , by inclining the DMD 50, the pitch P ₂ of the scanning locus of the exposure beams 53 from each micromirror (scan line), becomes narrower than the pitch P ₁ of the scanning line in the case of not tilting the DMD 50, greatly improve the resolution be able to. On the other hand, the inclination angle of the DMD 50 is small, the scanning width _{W 2} in the case of tilting the DMD 50, which is substantially equal to the scanning width _{W 1} when not inclined DMD 50.

Next, a method for increasing the modulation speed in the optical modulation means (hereinafter referred to as “high-speed modulation”) will be described.
When the laser light B is irradiated from the fiber array light source 66 to the DMD 50, the laser light emitted from the fiber array light source 66 is turned on and off for each pixel, and the pattern forming material 150 has approximately the same number of pixels as the DMD 50 used. Exposure is performed in elementary units (exposure area 168). Further, when the pattern forming material 150 is moved at a constant speed together with the stage 152, the pattern forming material 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162, and a strip-shaped exposed region 170 is provided for each exposure head 166. Is formed.
Here, there is a limit to the data processing speed of the entire DMD 50, and the modulation speed per line is determined in proportion to the number of pixels to be used. Therefore, one line can be obtained by using only a part of the micromirror array. The modulation speed per hit is increased. On the other hand, in the case of an exposure method in which the exposure head is continuously moved relative to the exposure surface, it is not necessary to use all the pixels in the sub-scanning direction.
In the DMD 50, 768 micromirror rows in which 1024 micromirrors are arranged in the main scanning direction are arranged in the subscanning direction, but a part of micromirror rows (eg, 1024 × 256 rows) is arranged by the controller 302. Only is controlled to drive.
4A and 4B are diagrams showing areas where DMD is used.
As shown in FIG. 4A, a micromirror array arranged at the center of the DMD 50 may be used as the DMD use area. As shown in FIG. 4B, the micromirror array arranged at the end of the DMD 50. May be used. In addition, when a defect occurs in some of the micromirrors, the micromirror array to be used may be appropriately changed depending on the situation, such as using a micromirror array in which no defect has occurred.
For example, in the case of using only 384 sets out of 768 sets of micromirror arrays, the modulation can be performed twice as fast per line as compared with the case of using all 768 sets. Also, when only 256 pairs are used in the 768 sets of micromirror arrays, modulation can be performed three times faster per line than when all 768 sets are used.

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

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

As the exposure method, as shown in FIG. 5, the entire surface of the pattern forming material 150 may be exposed by a single scan in the X direction by a scanner 162.
As the exposure method, as shown in FIGS. 6A and 6B, after the pattern forming material 150 is scanned in the X direction by the scanner 162, the scanner 162 is moved one step in the Y direction and scanned in the X direction. As described above, the entire surface of the pattern forming material 150 may be exposed by a plurality of scans by repeating scanning and moving.

  The exposure is performed on a partial area of the photosensitive layer to cure the partial area, and uncured areas other than the cured partial area are removed in a development step described later. A pattern is formed.

Next, the lens system 67 and the imaging optical system 51 will be described.
FIG. 11 is a cross-sectional view in the multiple scanning direction along the optical axis showing the details of the configuration of the exposure head in FIG.
As shown in FIG. 11, the lens system 67 includes a condensing lens 71 that condenses the laser light B as illumination light emitted from the fiber array light source 66, and a rod that is inserted in the optical path of the light that has passed through the condensing lens 71. And an imaging lens 74 disposed in front of the rod integrator 72, that is, on the mirror 69 side.
The condensing lens 71, the rod integrator 72, and the imaging lens 74 cause the laser light emitted from the fiber array light source 66 to enter the DMD 50 as a light beam that is close to parallel light and has a uniform beam cross-sectional intensity.

  The laser beam B emitted from the lens system 67 is reflected by the mirror 69 and irradiated to the DMD 50 via the TIR (total reflection) prism 70. In FIG. 10, the TIR prism 70 is omitted.

  As shown in FIG. 11, the imaging optical system 51 includes a first imaging optical system including lens systems 52 and 54, a second imaging optical system including lens systems 57 and 58, and these imaging optical systems. And an aperture array 59.

The microlens array 55 is formed by two-dimensionally arranging a large number of microlenses 55a corresponding to each picture element of the DMD 50. In this example, as will be described later, only 1024 × 256 rows of the 1024 × 768 rows of micromirrors of the DMD 50 are driven, and accordingly, 1024 × 256 rows of microlenses 55a are arranged.
The arrangement pitch of the micro lenses 55a is 41 μm in both the vertical direction and the horizontal direction. The focal length of the micro lens 55a is 0.19 mm, and the NA (numerical aperture) is 0.11.
Further, the microlens 55a is formed from the optical glass BK7.
The beam diameter of the laser beam B at the position of each microlens 55a is 41 μm.

  In the aperture array 59, a large number of apertures (openings) 59a corresponding to the respective microlenses 55a of the microlens array 55 are formed. The diameter of each aperture 59a is 10 μm.

The first imaging optical system forms an image on the microlens array 55 by enlarging the image by the DMD 50 three times.
The second imaging optical system enlarges the image that has passed through the microlens array 55 by 1.6 times, and forms and projects the image on the pattern forming material 150.
Accordingly, in the entire optical system, an image formed by the DMD 50 is magnified 4.8 times and formed and projected on the pattern forming material 150.

  A prism pair 73 is disposed between the second imaging optical system and the pattern forming material 150. By moving the prism pair 73 in the vertical direction in FIG. 11, an image on the pattern forming material 150 is obtained. The focus can be adjusted. In the figure, the pattern forming material 150 is sub-scanned in the direction of arrow F.

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

FIG. 13A is a cross-sectional view along the optical axis showing the configuration of the exposure head.
As shown in FIG. 13A, the exposure head includes a light irradiation means 144 for irradiating the DMD 50 with laser light, a lens system (imaging optical system) 454, 458 for enlarging the laser light reflected by the DMD 50 and forming an image. A microlens array 472 in which a large number of microlenses 474 are arranged corresponding to each pixel part of the DMD 50, an aperture array 476 in which a large number of apertures 478 are provided in correspondence with each microlens of the microlens array 472, and apertures It is composed of lens systems (imaging optical systems) 480 and 482 that image the passed laser beam on the exposed surface 56.

FIG. 14 is a diagram showing a result of measuring the flatness of the reflecting surface of the micromirror 62 constituting the DMD 50.
In FIG. 14, the same height positions of the reflecting surfaces are shown connected by contour lines, and the pitch of the contour lines is 5 nm. In the drawing, the x direction and the y direction are two diagonal directions of the micromirror 62, and the micromirror 62 rotates around the rotation axis extending in the y direction as described above.
15A and 15B show the height position displacement of the reflecting surface of the micromirror 62 along the x direction and the y direction in FIG. 14, respectively.
As shown in FIGS. 14 and 15, there is distortion on the reflection surface of the micromirror 62, and when attention is paid particularly to the center of the mirror, distortion in one diagonal direction (y direction) is different from that in the other diagonal line. It is larger than the distortion in the direction (x direction). For this reason, the problem that the shape in the condensing position of the laser beam B condensed with the micro lens 55a of the micro lens array 55 may be distorted may occur.

FIGS. 16A and 16B are views showing a front shape and a side shape of the entire microlens array 55, respectively.
As shown in FIG. 16A, the microlens array 55 is configured by arranging 1024 rows of microlenses 55a in the horizontal direction and 256 rows in the vertical direction corresponding to the micromirrors 62 of the DMD 50.
The long side dimension of the microlens array 55 is 50 mm, and the short side dimension is 20 mm.
In FIG. A, the arrangement order of the micro lenses 55a is indicated by j for the horizontal direction and k for the vertical direction.

FIGS. 17A and 17B are views showing a front shape and a side shape of the microlens constituting the microlens array. FIG. 17A also shows the contour lines of the microlens 55a.
As shown in FIGS. 17A and 17B, the end surface on the light exit side of the micro lens 55a has an aspherical shape that corrects aberration due to distortion of the reflection surface of the micro mirror 62.
Specifically, the aspherical microlens 55a is a toric lens having a radius of curvature Rx in the x direction of −0.125 mm and a radius of curvature Ry in the y direction of −0.1 mm.
FIG. 18 is a schematic view showing a condensing state by the microlens in one cross-section A and another cross-section B.
As shown in FIG. 18, since a toric lens having an aspherical end surface on the light emission side is used as the microlens 55a constituting the microlens array, the laser beam B in a cross section parallel to the x and y directions is used. In the light condensing state, when the parallel cross section in the x direction is compared with the parallel cross section in the y direction, the radius of curvature of the microlens 55a is smaller in the latter cross section, and the focal length becomes shorter. .

  The shape of the microlens 55a may be a secondary aspherical shape or a higher order (4th order, 6th order,...) Aspherical shape. By adopting the higher order aspherical shape, the beam shape can be further refined. Furthermore, it is possible to adopt a lens shape in which the curvatures in the x direction and the y direction described above coincide with each other in accordance with the distortion of the reflection surface of the micromirror 62. Hereinafter, examples of such lens shapes will be described in detail.

39A and 39B, the microlens 55a ″ showing the front shape and the side shape with contour lines, respectively, has the same curvature in the x direction and the y direction, and the curvature is the distance h from the lens center to the curvature Cy of the spherical lens. That is, the spherical lens shape that is the basis of the lens shape of the microlens 55a ″ is, for example, the lens height (in the optical axis direction of the lens curved surface) by the following formula (Equation 1). Position) The one that defines z is adopted.
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).

Then, the curvature Cy of the spherical lens shape is corrected according to the following formula (Equation 2) according to the distance h from the lens center to obtain the lens shape of the microlens 55a ″.

In the calculation formula (Equation 2), the meaning of z is the same as that of the above-described calculation equation (Equation 2). . The lens height z and the distance h when the curvature Cy = (1 / 0.1 mm), the fourth-order coefficient a = 1.2 × 10 ³ , and the sixth-order coefficient a = 5.5 × 10 ⁷ are described. The relationship is shown in a graph in FIG.

  In addition to making the end surface shape of the light exit side of the microlens 55a a toric surface, it is also possible to form a microlens array from microlenses in which one of the two light passage end surfaces is a spherical surface and the other is a cylindrical surface. It is.

19A, 19B, 19C, and 19D are diagrams showing the results of simulating the beam diameter in the vicinity of the condensing position (focal position) of the microlens 55a by a computer.
For comparison, FIGS. 20A, 20B, 20C, and 20D show the results of a similar simulation when the microlens has a spherical shape with a radius of curvature Rx = Ry = −0.1 mm. In addition, the value of z in each figure has shown the evaluation position of the focus direction of the micro lens 55a with the distance from the beam emission surface of the micro lens 55a.
The surface shape of the microlens 55a used for the simulation is calculated by the following calculation formula.

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

  19A to 19D and FIGS. 20A to 20D, in the pattern forming method of the present invention, the microlens 55a has a focal length in the cross section parallel to the y direction that is greater than the focal length in the cross section parallel to the x direction. Since the toric lens is also small, distortion of the beam shape in the vicinity of the condensing position is suppressed. Therefore, it is possible to expose the pattern forming material 150 with a higher definition image without distortion.

  In addition, when the magnitude relation of the distortion of the center part in the x direction and the y direction of the micromirror 62 is opposite to the above, the focal length in the parallel section in the x direction is the focal length in the parallel section in the y direction. If the microlens is formed of a smaller toric lens, the pattern forming material 150 can be similarly exposed to a higher-definition image without distortion.

The aperture array 59 is disposed in the vicinity of the light collection position of the microlens array 55. Only the light that has passed through the corresponding microlens 55 a is incident on each aperture 59 a provided in the aperture array 59. Accordingly, light from the adjacent microlens 55a not corresponding to one aperture 59a corresponding to one microlens 55a is prevented, and the extinction ratio can be increased.
If the diameter of the aperture 59a is reduced to some extent, an effect of suppressing the distortion of the beam shape at the condensing position of the micro lens 55a can be obtained, but the amount of light blocked by the aperture array 59 is increased, and the light utilization efficiency is reduced. . In this case, the microlens 55a having the aspherical shape prevents light from being blocked and keeps light use efficiency high.

  The micro lens array 55 and the aperture array 59 correct the aberration caused by the distortion of the reflection surface of the micro mirror 62 constituting the DMD 50. In the pattern forming method of the present invention using a spatial light modulation element other than the DMD. However, if there is distortion on the surface of the picture element portion of the spatial light modulator, the present invention can be applied to correct the aberration due to the distortion and prevent the beam shape from being distorted.

  In the pattern forming method of the present invention, the micro lens 55a which is a toric lens having different curvatures in the x direction and the y direction optically corresponding to the two diagonal directions of the micro mirror 62 is applied. 38A and 38B, the curvatures in the xx direction and the yy direction optically corresponding to the two side directions of the rectangular micromirror 62 are shown in FIGS. 38A and 38B, respectively. A microlens 55a ′ made of different toric lenses is also applicable.

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

As described above, in the pattern forming apparatus, the laser light reflected by the DMD 50 is magnified several times by the magnifying lenses 454 and 458 of the lens system and projected onto the exposed surface 56, so that the entire image area is Become wider. At this time, if the microlens array 472 and the aperture array 476 are not arranged, one pixel size (spot size) of each beam spot BS projected onto the exposed surface 56 is set to the exposure area 468 as shown in FIG. 13B. MTF (Modulation Transfer Function) characteristics representing the sharpness of the exposure area 468 are deteriorated.
On the other hand, since the pattern forming apparatus includes the micro lens array 472 and the aperture array 476, the laser light reflected by the DMD 50 corresponds to each pixel part of the DMD 50 by each micro lens of the micro lens array 472. Focused. Accordingly, 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 the MTF characteristic is deteriorated. And high-definition exposure can be performed.
Note that the exposure area 468 is inclined because the DMD 50 is inclined and disposed in order to eliminate the gap between the pixels.
In addition, the aperture array can shape the beam so that the spot size on the surface to be exposed 56 is constant even if the beam is thick due to the aberration of the micro lens. Thus, crosstalk between adjacent picture elements can be prevented by passing through the aperture array.
Further, by using a high-intensity light source for the light irradiating means 144, the angle of the light beam incident from the lens 458 to each microlens of the microlens array 472 is reduced, so that a part of the light flux of the adjacent pixel enters. Can be prevented. That is, a high extinction ratio can be realized.

22A and 22B are views showing the front shape and side shape of another microlens array.
As shown in FIG. 22, as another microlens array, each microlens is provided with a refractive index distribution for correcting aberration due to distortion of the reflecting surface of the micromirror 62.
As illustrated, the external shape of the other microlens 155a is a parallel plate. The x and y directions in the figure are as described above.
FIG. 23 is a schematic view showing a condensing state of the laser beam B in the cross section parallel to the x direction and the y direction by the micro lens 155a of FIG.
As shown in FIG. 23, the microlens 155a has a refractive index distribution that gradually increases outward from the optical axis O. In FIG. 23, the broken line in the microlens 155a indicates that the refractive index is light. A position changed from the axis O at a predetermined equal pitch is shown. As shown in the drawing, when the parallel cross section in the x direction is compared with the parallel cross section in the y direction, the ratio of the refractive index change of the microlens 155a is larger in the latter cross section, and the focal length is shorter. It has become. Even when a microlens array composed of such a gradient index lens is used, it is possible to obtain the same effect as when the microlens array 55 is used.
In addition, in the microlens 55a shown in FIGS. 17 and 18, the refractive index distribution is given together, and the aberration due to the distortion of the reflecting surface of the micromirror 62 can be corrected by both the surface shape and the refractive index distribution. Is possible.

Next, another example of the microlens array will be described with reference to the drawings.
As shown in FIG. 42, the microlens array of this example is formed by arranging microlenses having a lens opening shape that does not allow the light from the peripheral portion of the picture element portion to enter.

  As described above with reference to FIGS. 14 and 15, there is distortion on the reflection surface of the micromirror 62 of the DMD 50, but the amount of change in distortion gradually increases from the center of the micromirror 62 toward the periphery. Has a trend. The amount of change in peripheral distortion in one diagonal direction (y direction) of the micromirror 62 is larger than the amount of change in peripheral distortion in another diagonal direction (x direction), and the above-described tendency is more remarkable. .

  The microlens array of this example is applied to cope with the above-described problem. In the microlens array 255, the microlenses 255a arranged in an array have a circular lens opening. Therefore, as described above, the laser light B reflected at the peripheral portion of the reflecting surface of the micromirror 62 having a large distortion, particularly at the four corners, is not condensed by the microlens 255a, and the condensing position of the condensed laser light B is reduced. Can be prevented from being distorted. Therefore, a higher-definition image without distortion can be exposed to the pattern forming material 150.

  In the microlens array 255, as shown in FIG. 42, the back surface of the transparent member 255b holding the microlens 255a (which is usually formed integrally with the microlens 255a), that is, the microlens 255a. A light-shielding mask 255c is formed on the surface opposite to the surface on which the lens openings are formed so as to fill the outer regions of the lens openings of the plurality of microlenses 255a separated from each other. By providing such a mask 255c, the laser beam B reflected at the periphery of the reflecting surface of the micromirror 62, particularly at the four corners, is absorbed and blocked there, so the shape of the focused laser beam B Is more reliably prevented from being distorted.

  In the microlens array 255, the opening shape of the microlens is not limited to the circular shape described above. For example, as shown in FIG. 43, a microlens array in which a plurality of microlenses 455a having elliptical openings are arranged in parallel. As shown in FIG. 44, a microlens array 555 formed by arranging a plurality of microlenses 555a having polygonal (quadrangle in the illustrated example) openings can be used. Note that the microlenses 455a and 555a are formed by cutting out a part of a normal axisymmetric spherical lens into a circular shape or a polygonal shape, and have a light collecting function similar to that of a normal axisymmetric spherical lens.

  Furthermore, in the present invention, it is possible to apply a microlens array as shown in A, B and C of FIG. A microlens array 655 shown in FIG. 6A is arranged in parallel so that a plurality of microlenses 655a similar to the microlenses 55a, 455a, and 555a are in close contact with the surface of the transparent member 655b on the side where the laser beam B is emitted. Then, a mask 655c similar to the mask 255c is formed on the surface on which the laser beam B is incident. Note that the mask 255c in FIG. 42 is formed in the outer portion of the lens opening, whereas the mask 655c is provided in the lens opening. In the microlens array 755 shown in FIG. 5B, a plurality of microlenses 755a are arranged in parallel on the surface of the transparent member 455b on the side where the laser beam B is emitted, and a mask 755c is provided between the microlenses 755a. Formed. Further, in the microlens array 855 shown in FIG. 6C, a plurality of microlenses 855a are arranged in parallel with each other on the surface of the transparent member 855b on the side where the laser beam B is emitted, and each microlens 855a has a peripheral portion. A mask 855c is formed.

  The masks 655c, 755c, and 855c all have a circular opening as in the above-described mask 255c, whereby the opening of the microlens is defined to be circular.

  FIG. 17 shows a configuration in which a lens opening shape that does not allow light from the periphery of the micromirror 62 of the DMD 50 to enter by providing a mask, such as the microlenses 255a, 455a, 555a, 655a, and 755a described above. An aspherical lens that corrects aberration due to the distortion of the surface of the micromirror 62 like the microlens 55a described above, or a lens having a refractive index distribution that corrects the aberration like the microlens 155a shown in FIG. It is also possible to employ them. By doing so, the effect of preventing the distortion of the exposure image due to the distortion of the reflection surface of the micromirror 62 is synergistically enhanced.

  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 has the above-described aspherical shape and refractive index distribution. In addition, for example, when the imaging position of the first imaging optical system such as the lens systems 52 and 54 shown in FIG. 11 is set on the lens surface of the microlens 855a, the light utilization efficiency is particularly high. The pattern forming material 150 can be exposed with higher intensity light. That is, at that time, the first imaging optical system refracts the light so that stray light due to the distortion of the reflection surface of the micromirror 62 is focused at one point at the imaging position of the optical system. If the mask 855c is formed, light other than stray light is not shielded, and light use efficiency is improved.

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

FIG. 24 is an explanatory diagram showing the concept of correction by the light quantity distribution correction optical system.
As shown in FIG. 24A, a description will be given of a case where the entire luminous flux width (total luminous flux width) H0 and H1 is the same for the incident luminous flux and the outgoing luminous flux. In FIG. 24A, the portions denoted by reference numerals 51 and 52 virtually indicate the entrance surface and the exit surface in the light quantity distribution correction optical system.
In the light quantity distribution correcting optical system, it is assumed that the light flux widths h0 and h1 of the light beam incident on the central portion near the optical axis Z1 and the light beam incident on the peripheral portion are the same (h0 = hl). The light quantity distribution correcting optical system expands the light flux width h0 of the incident light beam in the central portion with respect to the light having the same light flux widths h0 and h1 on the incident side, and conversely changes the incident light flux in the peripheral portion. On the other hand, the light beam width h1 is reduced. That is, the width h10 of the outgoing light beam at the center and the width h11 of the outgoing light beam at the periphery are set to satisfy h11 <h10. In terms of the ratio of the luminous flux width, the ratio “h11 / h10” of the luminous flux width in the peripheral portion to the luminous flux width in the central portion on the emission side is smaller than the ratio on the incident side (h1 / h0 = 1) ( (H11 / h10) <1).

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

  The operations and effects of the light quantity distribution correcting optical system are the same when the entire light flux width is changed between the incident side and the exit side (FIGS. 24B and 24C).

  FIG. 24B shows a case where the entire light flux width H0 on the incident side is “reduced” to the width H2 and emitted (H0> H2). Even in such a case, the light quantity distribution correcting optical system has the same light beam width h0, h1 on the incident side, and the light beam width h10 in the central part is larger than that in the peripheral part on the emission side. Conversely, the luminous flux width h11 at the peripheral part is made smaller than that at the central part. Considering the reduction rate of the light beam, the reduction rate with respect to the incident light beam in the central part is made smaller than that in the peripheral part, and the reduction rate with respect to the incident light beam in the peripheral part is made larger than that in the central part. Also in this case, the ratio “H11 / H10” of the light flux width in the peripheral portion to the light flux width in the central portion is smaller than the ratio (h1 / h0 = 1) on the incident side ((h11 / h10) <1). .

  FIG. 24C shows a case where the entire light flux width H0 on the incident side is “enlarged” by the width Η3 and emitted (H0 <H3). Even in such a case, the light quantity distribution correcting optical system has the same light beam width h0, h1 on the incident side, and the light beam width h10 in the central part is larger than that in the peripheral part on the emission side. Conversely, the luminous flux width h11 at the peripheral part is made smaller than that at the central part. Considering the expansion rate of the light beam, the expansion rate for the incident light beam in the central portion is made larger than that in the peripheral portion, and the expansion rate for the incident light beam in the peripheral portion is made smaller than that in the central portion. Also in this case, the ratio “h11 / h10” of the light flux width in the peripheral portion to the light flux width in the central portion is smaller than the ratio (h1 / h0 = 1) on the incident side ((h11 / h10) <1). .

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

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

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

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

  The aspheric data is expressed by a coefficient in the following formula (A) that represents the aspheric shape.

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

FIG. 26 shows a light amount distribution of illumination light obtained by the pair of combination lenses shown in Tables 1 and 2. Here, the horizontal axis represents coordinates from the optical axis, and the vertical axis represents the light amount ratio (%). For comparison, FIG. 25 shows a light amount distribution (Gaussian distribution) of illumination light when correction is not performed.
As shown in FIG. 25 and FIG. 26, by performing correction with the light amount distribution correcting optical system, a substantially uniform light amount distribution is obtained as compared with the case where correction is not performed. As a result, it is possible to perform exposure with uniform laser light without reducing the efficiency of use of light without lowering the light utilization efficiency.

Next, the fiber array light source 66 as a light irradiation means will be described.
27A (A) is a perspective view showing the configuration of the fiber array light source, FIG. 27A (B) is a partially enlarged view of (A), and FIGS. 27A (C) and (D) are laser emitting portions. It is a top view which shows the arrangement | sequence of the light emission point in. FIG. 27B is a front view showing the arrangement of the light emitting points in the laser emission part of the fiber array light source.

  As shown in FIG. 27A, the fiber array light source 66 includes a plurality of (for example, 14) laser modules 64, and one end of the multimode optical fiber 30 is coupled to each laser module 64. An optical fiber 31 having the same core diameter as that of the multimode optical fiber 30 and a smaller cladding diameter than the multimode optical fiber 30 is coupled to the other end of the multimode optical fiber 30. As shown in detail in FIG. 27B, seven ends of the multimode optical fiber 31 on the side opposite to the optical fiber 30 are arranged along the main scanning direction orthogonal to the sub-scanning direction, and these are arranged in two rows to form a laser. An emission unit 68 is configured.

  As shown in FIG. 27B, the laser emitting portion 68 is sandwiched and fixed between two support plates 65 having a flat surface. In addition, a transparent protective plate such as glass is preferably disposed on the light emitting end face of the multimode optical fiber 31 for protection. The light exit end face of the multimode optical fiber 31 has high light density and is likely to collect dust and easily deteriorate. However, the protective plate as described above prevents the dust from adhering to the end face and deteriorates. Can be delayed.

  Further, in order to arrange the emission ends of the optical fibers 31 having a small cladding diameter in a row without any gaps, the multi-mode optical fibers 30 are stacked between two adjacent multi-mode optical fibers 30 in a portion having a large cladding diameter, The exit end of the optical fiber 31 coupled to the stacked multi-mode optical fiber 30 is between the two exit ends of the optical fiber 31 coupled to the two adjacent multi-mode optical fibers 30 at a portion where the cladding diameter is large. It is arranged to be sandwiched between.

  In such an optical fiber, as shown in FIG. 28, an optical fiber 31 having a length of 1 to 30 cm and having a small cladding diameter is coaxially provided at the tip of the multimode optical fiber 30 having a large cladding diameter on the laser light emission side. It can be obtained by bonding. In the two optical fibers, the incident end face of the optical fiber 31 is fused and joined to the outgoing end face of the multimode optical fiber 30 so that the central axes of both optical fibers coincide. As described above, the diameter of the core 31 a of the optical fiber 31 is the same as the diameter of the core 30 a of the multimode optical fiber 30.

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

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

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

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

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

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

  As shown in FIGS. 30 and 31, the combined laser light source is housed in a box-shaped package 40 having an upper opening together with other optical elements. The package 40 includes a package lid 41 created so as to close the opening thereof. After the deaeration process, a sealing gas is introduced, and the package 40 and the package lid 41 are closed by closing the opening of the package 40 with the package lid 41. 41. The combined laser light source is hermetically sealed in a closed space (sealed space) formed by 41.

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

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

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

  FIG. 32 shows the front shape of the attachment part of the collimator lenses 11-17. Each of the collimator lenses 11 to 17 is formed in a shape obtained by cutting a region including the optical axis of a circular lens having an aspherical surface into an elongated shape on a parallel plane. This elongated collimator lens can be formed, for example, by molding resin or optical glass. The collimator lenses 11 to 17 are closely arranged in the arrangement direction of the light emitting points so that the length direction is orthogonal to the arrangement direction of the light emitting points of the GaN-based semiconductor lasers LD1 to LD7 (left and right direction in FIG. 32).

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

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

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

Since the fiber array light source uses a high-intensity fiber array light source in which the output ends of the optical fibers of the combined laser light source are arranged in an array as the light irradiating means for illuminating the DMD, it has a high output and a deep focus. A pattern forming apparatus having a depth can be realized. Furthermore, since the output of each fiber array light source is increased, the number of fiber array light sources required to obtain a desired output is reduced, and the cost of the pattern forming apparatus can be reduced.
Further, since the cladding diameter of the output end of the optical fiber is smaller than the cladding diameter of the incident end, the diameter of the light emitting portion is further reduced, and the brightness of the fiber array light source can be increased. Thereby, a pattern forming apparatus having a deeper depth of focus can be realized. For example, even in the case of ultra-high resolution exposure with a beam diameter of 1 μm or less and a resolution of 0.1 μm or less, a deep depth of focus can be obtained, and high-speed and high-definition exposure is possible. Therefore, it is suitable for a thin film transistor (TFT) exposure process that requires high resolution.

  The light irradiating means is not limited to a fiber array light source including a plurality of the combined laser light sources. For example, a single laser beam that emits laser light incident from a single semiconductor laser having one light emitting point is emitted. A fiber array light source obtained by arraying fiber light sources including optical fibers can be used.

  As the light irradiation means having a plurality of light emitting points, for example, as shown in FIG. 33, a laser array in which a plurality of (for example, seven) chip-shaped semiconductor lasers LD1 to LD7 are arranged on the heat block 100 is used. Can be used. It is also possible to use a chip-shaped multicavity laser 110 in which a plurality of (for example, five) light emitting points 110a shown in FIG. 34A are arranged in a predetermined direction. Since the multicavity laser 110 can arrange the light emitting points with higher positional accuracy than the case where the chip-shaped semiconductor lasers are arranged, it is easy to multiplex laser beams emitted from the respective light emitting points. However, as the number of light emitting points increases, the multicavity laser 110 is likely to be bent at the time of laser manufacturing. Therefore, the number of light emitting points 110a is preferably 5 or less.

  As the light irradiation means, as shown in FIG. 34B, a plurality of multi-cavity lasers 110 are arranged on the heat block 100 in the same direction as the arrangement direction of the light emitting points 110a of each chip. A multi-cavity laser ray can be used as a laser light source.

The combined laser light source is not limited to one that combines laser beams emitted from a plurality of chip-shaped semiconductor lasers.
For example, as shown in FIG. 21, a combined laser light source including a chip-shaped multicavity laser 110 having a plurality of (for example, three) light emitting points 110a can be used. This combined laser light source is configured to include a multi-cavity laser 110, one multi-mode optical fiber 130, and a condensing lens 120. The multi-cavity laser 110 can be composed of, for example, a GaN-based laser diode having an oscillation wavelength of 405 nm.

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

  A plurality of light emitting points 110 a of the multicavity laser 110 are arranged in parallel within a width substantially equal to the core diameter of the multimode optical fiber 130, and a focal point substantially equal to the core diameter of the multimode optical fiber 130 is formed as the condenser lens 120. By using a convex lens of a distance or a rod lens that collimates the outgoing beam from the multicavity laser 110 only in a plane perpendicular to the active layer, the coupling efficiency of the laser beam B to the multimode optical fiber 130 can be increased. it can.

  As shown in FIG. 35, a multi-cavity laser 110 having a plurality of (for example, three) emission points is used, and a plurality of (for example, nine) multi-cavity lasers 110 are equidistant from each other on the heat block 111. A combined laser light source including the laser array 140 arranged in (1) can be used. The plurality of multi-cavity lasers 110 are arranged and fixed in the same direction as the arrangement direction of the light emitting points 110a of each chip.

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

  In the above configuration, each of the laser beams B emitted from each of the plurality of light emitting points 110a of the plurality of multi-cavity lasers 110 is condensed in a predetermined direction by the rod lens 113, and then each microlens of the lens array 114. It becomes parallel light. 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 in the optical fiber, is combined into one, and is emitted.

  Furthermore, as another combined laser light source, as shown in FIGS. 36A and B, a heat block 182 having an L-shaped cross section in the optical axis direction is mounted on a substantially rectangular heat block 180, and two heat blocks are mounted. A storage space is formed between them. On the upper surface of the L-shaped heat block 182, a plurality of (for example, two) multi-cavity lasers 110 in which a plurality of light emitting points (for example, five) are arranged in an array form the light emitting points 110a of each chip. It is arranged and fixed at equal intervals in the same direction as the arrangement direction.

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

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

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

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

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

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

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

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

The condensing optical system includes collimator lenses 11 to 17 and a condensing lens 20. Also, the converging optical system and the multimode optical fiber 30 constitute a multiplexing optical system.
The laser beams B1 to B7 condensed as described above by the condenser lens 20 are incident on the core 30a of the multimode optical fiber 30, propagate through the optical fiber, and are combined into one laser beam B. The light exits from the optical fiber 31 coupled to the exit end of the multimode optical fiber 30.

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

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

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

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

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

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

Next, the pattern forming method of the present invention using the pattern forming apparatus will be described.
First, pattern information corresponding to the exposure pattern is input to a controller (not shown) connected to the DMD 50 and temporarily stored in a frame memory in the controller. This pattern information is data representing the density of each pixel constituting the image as binary values (whether or not dots are recorded).
Next, the stage 152 having the pattern forming material 150 adsorbed on the surface thereof is moved at a constant speed from the upstream side to the downstream side of the gate 160 along the guide 158 by a driving device (not shown). When the leading edge of the pattern forming material 150 is detected by the detection sensor 164 attached to the gate 160 when the stage 152 passes under the gate 160, the pattern information stored in the frame memory is sequentially read out for a plurality of lines. Then, a control signal is generated for each exposure head 166 based on the pattern information read by the data processing unit. Then, each of the micromirrors of the DMD 50 is on / off controlled for each exposure head 166 based on the generated control signal by the mirror drive control unit.
Next, when the DMD 50 is irradiated with laser light from the fiber array light source 66, the laser light reflected when the micromirrors of the DMD 50 are turned on is exposed to the exposed surface 56 of the pattern forming material 150 by the lens systems 54 and 58. Imaged on top.
In this manner, the laser light emitted from the fiber array light source 66 is turned on / off for each pixel, and the pattern forming material 150 is exposed in approximately the same number of pixel units (exposure area 168) as the number of used pixel elements of the DMD 50. The
Further, when the pattern forming material 150 is moved at a constant speed together with the stage 152, the pattern forming material 150 is sub-scanned in the direction opposite to the stage moving direction by the scanner 162, and a strip-shaped exposed region 170 is provided for each exposure head 166. Is formed.

[Development process]
The developing step is a step of forming a permanent pattern by exposing the photosensitive layer by the exposing step, curing the exposed region of the photosensitive layer, and then developing by removing the uncured region.

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

  The developer is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include alkali metal or alkaline earth metal hydroxides or carbonates, bicarbonates, aqueous ammonia, and quaternary ammonium. An aqueous salt solution is preferred. Among these, an aqueous sodium carbonate solution is particularly preferable.

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

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

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

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

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

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

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

Since the pattern forming method of the present invention can form a pattern at high speed, it can be widely used for forming various patterns, and can be particularly suitably used for forming a flexible wiring pattern substrate.
The permanent pattern formed by the pattern forming method of the present invention has excellent surface hardness, insulation, heat resistance and the like, and can be suitably used as a protective film, an interlayer insulating film, and a solder resist pattern.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

(Synthesis Example 1)
-Synthesis of polyurethane resin having carboxyl group-
125 g of 4,4′-diphenylmethane diisocyanate represented by the following structural formula (1) and 67 g of 2,2-bis (hydroxymethyl) propionic acid represented by the following structural formula (2) are placed in a 500 mL three-necked flask. Dissolved in 290 ml of dioxane. Next, 1 g of N, N-diethylaniline was added to this solution and stirred for 6 hours under reflux of dioxane. After reaction, the obtained solution was added little by little into a solution of 4 L of water and 40 mL of acetic acid. The polymer was precipitated. The obtained solid was vacuum dried to synthesize 185 g of polyurethane resin (A). The acid value of this polyurethane resin (A) was 138 mgKOH / g. It was 28,000 when the weight average molecular weight (polystyrene conversion) was measured by GPC.

(Synthesis Example 2)
-Synthesis of polyurethane resin having carboxyl group-
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 this polyurethane resin (B) was 137 mgKOH / g.

(Synthesis Example 3)
-Synthesis of polyurethane resin having carboxyl group-
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 in Synthesis Example 1. The acid value of this polyurethane resin (C) was 126 mgKOH / g.

(Synthesis Example 4)
-Synthesis of polyurethane resin having carboxyl group-
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 in Synthesis Example 1. The acid value of this polyurethane resin (D) was 172 mgKOH / g.

(Synthesis Example 5)
-Synthesis of polyurethane resin having carboxyl group-
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 in Synthesis Example 1. The acid value of this polyurethane resin (E) was 148 mgKOH / g.

(Synthesis Example 6)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a diisocyanate compound represented by the following structural formula (7) is used instead of 4,4′-diphenylmethane diisocyanate, and the following structural formula (8) is used instead of 2,2-bis (hydroxymethyl) propionic acid. A polyurethane resin (F) was synthesized in the same manner as in Synthesis Example 1 except that the diol compound represented by The acid value of this polyurethane resin (F) was 118 mgKOH / g.

(Synthesis Example 7)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a diisocyanate compound represented by the following structural formula (9) was used instead of 4,4′-diphenylmethane diisocyanate, and the following structural formula (10) was used instead of 2,2-bis (hydroxymethyl) propionic acid. A polyurethane resin (G) was synthesized in the same manner as in Synthesis Example 1 except that the diol compound represented by The acid value of this polyurethane resin (G) was 130 mgKOH / g.

(Synthesis Example 8)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a diisocyanate compound represented by the following structural formula (11) was used instead of 4,4′-diphenylmethane diisocyanate, and the following structural formula (12) was used instead of 2,2-bis (hydroxymethyl) propionic acid. A polyurethane resin (H) was synthesized in the same manner as in Synthesis Example 1 except that the diol compound represented by The acid value of this polyurethane resin (H) was 116 mgKOH / g.

(Synthesis Example 9)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a diisocyanate compound represented by the following structural formula (13) was used instead of 4,4′-diphenylmethane diisocyanate, and the following structural formula (14) was used instead of 2,2-bis (hydroxymethyl) propionic acid. A polyurethane resin (I) was synthesized in the same manner as in Synthesis Example 1 except that the diol compound represented by The acid value of this polyurethane resin (I) was 99 mgKOH / g.

(Synthesis Example 10)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a polyurethane resin (J) was prepared in the same manner as in Synthesis Example 1 except that a diol compound represented by the following structural formula (15) was used instead of 2,2-bis (hydroxymethyl) propionic acid. Was synthesized. The acid value of this polyurethane resin (J) was 88 mgKOH / g.

(Synthesis Example 11)
-Synthesis of polyurethane resin having carboxyl group-
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, polyurethane resin (K) Was synthesized. The acid value of this polyurethane resin (K) was 82 mgKOH / g.

(Synthesis Example 12)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a diisocyanate compound represented by the following structural formula (6) was used instead of 4,4′-diphenylmethane diisocyanate, and the following structural formula (17) was used instead of 2,2-bis (hydroxymethyl) propionic acid. A polyurethane resin (L) was synthesized in the same manner as in Synthesis Example 1 except that the diol compound represented by The acid value of this polyurethane resin (L) was 92 mgKOH / g.

(Synthesis Example 13)
-Synthesis of polyurethane resin having carboxyl group-
In Synthesis Example 1, a diisocyanate compound represented by the following structural formula (6) was used instead of 4,4′-diphenylmethane diisocyanate, and the following structural formula (18) was used instead of 2,2-bis (hydroxymethyl) propionic acid. A polyurethane resin (M) was synthesized in the same manner as in Synthesis Example 1 except that the diol compound represented by The acid value of this polyurethane resin (M) was 87 mgKOH / g.

(Comparative Synthesis Example 1)
1 equivalent of a cresol novolac type epoxy resin having an epoxy equivalent of 217 and an average of 7 phenol nucleus residues in one molecule and an epoxy group, and 1.05 equivalent of acrylic acid Reacted. A viscous liquid (epoxy acrylate resin) containing 35% by mass of phenoxyethyl acrylate was prepared by reacting the obtained reaction product with 0.69 equivalents of tetrahydrophthalic anhydride in a conventional manner using phenoxyethyl acrylate as a solvent. did. This epoxy acrylate resin showed an acid value of 63.4 mg KOH / g as a mixture.

(Comparative Synthesis Example 2)
In a flask equipped with a stirrer, reflux condenser, inert gas inlet, and thermometer, 1,000 g of polytetramethylene ether glycol (PTG, average molecular weight 1,000) and 405 g of sebacic acid were charged for 2 hours. The temperature was raised to 200 ° C. and the reaction was further continued for 3 hours, followed by cooling to synthesize polycarboxylic acid compounds of both ends of polytetramethylene ether glycol having an acid value of 81.9 and a molecular weight of 1,370.

Next, 100 g of γ-butyrolactone and 50 g of N-methylpyrrolidone (NMP) were charged into a flask equipped with a stirrer, a reflux condenser, an inert gas inlet, and a thermometer. Furthermore, 55.6 g of both end carboxylic acids of the above polytetramethylene ether glycol, 6.1 g of adipic acid, 8.3 g of sebacic acid, 13.7 g of isophthalic acid, 13.8 g of 4,4′-diphenylmethane diisocyanate (MDI), tri Polyisocyanate (Coronate T80, manufactured by Nippon Polyurethane Industry Co., Ltd.) 14.4 g was charged, heated to 200 ° C., kept warm for 4 hours and then cooled, polyamide having a heating residue of 40% by mass and an acid value (solid content) of 83.5 Resin was synthesized.
Furthermore, 141.5 g of bisphenol A type epoxy resin Epicoat 1001 (manufactured by oil-based shell epoxy) was charged and kept at 140 ° C. for 2 hours, and then dimethylformamide (DMF) was added to make the heating residue 40% by mass. After adding 10.7 g of acrylic acid at 120 ° C. and keeping it warm for 3 hours, 90.6 g of tetrahydrophthalic anhydride (THPA) was added and kept warm for 1 hour. Next, 58.4 g of glycidol was added and kept warm for 2 hours, and then 240 g of tetrahydrophthalic anhydride (THPA) was added and kept warm for 2 hours. Next, the resultant was diluted with dimethylformamide (DMF) to synthesize a photosensitive polyamide resin having a heating residue of 55% by mass and an acid value (solid content) of 145 mgKOH / g.

(Comparative Synthesis Example 3)
In a flask equipped with a stirrer, a reflux condenser, and a thermometer, α, ω-polybutadienedicarboxylic acid (NISSO-PBC-1000, manufactured by Nippon Soda Co., Ltd.) 482.6 parts by mass, brominated bisphenol A type epoxy resin ( 400 parts by mass of YDB-400 (manufactured by Toto Kasei Co., Ltd.), 183 parts by mass of carbitol acetate, and 110 parts by mass of solvent naphtha (Solvesso 150) were added and heated at 110 ° C. for 8 hours. This was charged with 36.4 parts by weight of acrylic acid, 0.5 parts by weight of methylhydroquinone, and 6 parts by weight of carbitol acetate. At 70 ° C, 3 parts by weight of triphenylphosphine and 6 parts by weight of solvent naphtha were charged and heated to 100 ° C. The reaction was continued until the solid content acid value reached 2 KOHmg / g or less. Next, the resulting solution was cooled to 50 ° C., charged with 100 parts by mass of tetrahydrophthalic anhydride, 126 parts by mass of carbitol acetate, and 6 parts by mass of solvent naphtha, reacted at 80 ° C. for a predetermined time, and had a solid content acid value of 59 KOH mg. / G, an unsaturated group-containing polycarboxylic acid resin having a solid content of 40% by mass was synthesized.

  In a flask equipped with a stirrer, reflux condenser, inert gas inlet, and thermometer, 100 g of γ-butyrolactone and 50 g of N-methylpyrrolidone (NMP) were charged, and the unsaturated group-containing polycarboxylic acid resin 74. 6 g, adipic acid 3.3 g, sebacic acid 4.6 g, isophthalic acid 7.5 g, 4,4′-diphenylmethane diisocyanate (MDI) 4.8 g, tolylene diisocyanate (Coronate T80, manufactured by Nippon Polyurethane Industry Co., Ltd.) 13.4 g The mixture was heated to 200 ° C., kept warm for 4 hours, and then cooled to obtain a polyamide resin having a heating residue of 40% by mass and an acid value (solid content) of 58.6. Furthermore, 27.6 g of bisphenol A type epoxy resin (Epomic R140, manufactured by Mitsui Petrochemical Co., Ltd.) was added, and after keeping at 140 ° C. for 2 hours, dimethylformamide (DMF) was added to make the heating residue 40% by mass. At 120 ° C., 3.3 g of methacrylic acid was added and kept for 3 hours, and then 37.9 g of tetrahydrophthalic anhydride (THPA) was added and kept for 1 hour. Subsequently, it diluted with dimethylformamide (DMF) and synthesize | combined the photosensitive polyamide resin of 55 mass% of heating residues, and acid value (solid content) 74KOHmg / g.

  In a flask equipped with a stirrer, a reflux condenser, and a thermometer, 200 parts by mass of a cresol novolac type epoxy resin (epoxy equivalent: 200), 20 parts by mass of acrylic acid, 0.4 parts by mass of methyl hydroquinone, and 80 parts by mass of carbitol acetate. Part and 20 parts by mass of solvent naphtha were heated and stirred at 70 ° C. to dissolve the mixture. Next, the solution was cooled to 50 ° C., charged with 0.5 parts by mass of triphenylphosphine, heated to 100 ° C., and reacted until the solid content acid value was 1 KOH mg / g or less. 10 parts by mass of solvent naphtha was charged, and a resin containing an acrylate group and an epoxy group having a solid content of 67% by mass was synthesized.

(Comparative Synthesis Example 4)
First, a copolymer composed of styrene / n-butyl acrylate / maleic anhydride (molar ratio = 41/24/35) was synthesized by a dropping polymerization method.
Next, 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 completed by further stirring for 6 hours at room temperature. A solution (solid content: 36.8% by mass) was synthesized.
The acid value of the obtained resin was an acid value of 135 KOH mg / g, the weight average molecular weight was 30,000, and the solid content concentration was 36.8% by mass.

(Example 1)
-Fabrication of flexible printed circuit board-
24.75 parts by mass of the polyurethane resin (A) of Synthesis Example 1, 13.36 parts by mass of methoxypropanol, 3.06 parts by mass of a bifunctional acrylic monomer (R712, manufactured by Nippon Kayaku Co., Ltd.), 4.59 of dipentaerythritol hexaacrylate Parts by mass, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (Ciba Specialty Chemicals) 1.98 parts by mass, hexamethoxymethylmelamine (MW30HM, Sanwa Chemical Co., Ltd.) 5.00 parts by mass 1 part by weight, 1.0 part by weight of a phthalocyanine green dispersion (in a concentration of 10% by weight methoxypropanol) and 0.066 part by weight of a 30% by weight methyl ethyl ketone solution of F780F (manufactured by Dainippon Ink & Chemicals, Inc.) A sex composition was prepared.

  The barium sulfate dispersion was composed of 30 parts by mass of barium sulfate (manufactured by Sakai Chemical Co., Ltd., B30), 34.29 parts by mass of a 35% by mass methyl ethyl ketone solution of the styrene / maleic anhydride / butyl acrylate copolymer, -35.71 parts by mass of methoxy-2-propylacetate was mixed in advance, and then the motor mill M-200 (manufactured by Eiger) was used with zirconia beads having a diameter of 1.0 mm at a peripheral speed of 9 m / s. Prepared by dispersing for 5 hours.

  Next, the obtained photosensitive composition solution was applied onto a two-layer flexible substrate (copper thickness 35 μm / resin thickness 25 μm) by bar coating so that the film thickness after drying was 35 μm, It was dried in an oven for 30 minutes to form a photosensitive layer.

<Exposure process>
Using a pattern forming apparatus described below, the photosensitive layer on the substrate is irradiated with a laser beam having a wavelength of 405 nm so that a 15-step step wedge pattern (Δlog E = 0.15) and a desired wiring pattern can be obtained. Then, a portion of the photosensitive layer was cured.

-Pattern forming device-
27 to 32 as the light irradiating means, and 768 sets of micromirror arrays in which 1024 micromirrors are arranged in the main scanning direction shown in FIG. 4 as the light modulating means are arranged in the sub-scanning direction. Among the optical modulation means, the DMD 50 controlled to drive only 1024 × 256 rows and the microlens array in which the microlenses shown in FIG. 13 whose one surface is a toric surface are arranged in an array. A pattern forming apparatus having 472 and optical systems 480 and 482 for forming an image of light passing through the microlens array on the photosensitive layer was used.

  As the microlens, a toric lens 55a is used as shown in FIGS. 17 and 18, and the radius of curvature Rx = −0.125 mm in a direction optically corresponding to the x direction corresponds to the y direction. The radius of curvature Ry in the direction to travel is −0.1 mm.

  In addition, the aperture array 59 disposed in the vicinity of the condensing position of the microlens array 55 is disposed so that only light that has passed through the corresponding microlens 55a is incident on each aperture 59a.

Next, spray development (spray pressure: 2.0 kgf / cm ² ) was carried out for 60 seconds using a 1% by mass aqueous sodium carbonate solution to remove unexposed portions. Next, using a circulation oven, heat curing was performed at 160 ° C. for 1 hour to produce a flexible printed circuit board.

(Example 2)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1, except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (B) in Synthesis Example 2. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 3)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1, except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (C) in Synthesis Example 3. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

Example 4
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (D) in Synthesis Example 4. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 5)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (E) in Synthesis Example 5. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 6)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1, except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (F) in Synthesis Example 6. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 7)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1, except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (G) in Synthesis Example 7. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 8)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (H) in Synthesis Example 8. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

Example 9
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (I) in Synthesis Example 9. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 10)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (J) in Synthesis Example 10. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 11)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (K) in Synthesis Example 11. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 12)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (L) in Synthesis Example 12. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Example 13)
-Fabrication of flexible printed circuit board-
In Example 1, a photosensitive composition was prepared and a photosensitive layer was formed in the same manner as in Example 1 except that the polyurethane resin (A) in Synthesis Example 1 was replaced with the polyurethane resin (M) in Synthesis Example 13. did. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Comparative Example 1)
-Fabrication of flexible printed circuit board-
40 parts by mass of 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, leveling agent (Modaflow (Manufactured by Monsanto, USA) 1.0 part by mass, 26 parts by mass of barium sulfate, and 0.5 part by mass of phthalocyanine green were kneaded by a three-roll mill to prepare an ink. Subsequently, the obtained ink was mixed with 15 parts by weight of trimethylolpropane triglycidyl ether to prepare a photosensitive composition.
About the obtained photosensitive composition solution, it applied to the whole surface of the flexible substrate by the screen-printing method like Example 1, and it dried for 30 minutes at 80 degreeC, and formed the photosensitive layer with a dry film thickness of 35 micrometers. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Comparative Example 2)
-Fabrication of flexible printed circuit board-
91 parts by weight of photosensitive polyamide resin synthesized in Comparative Synthesis Example 2, 10 parts by weight of pentaerythritol hexaacrylate, 22 parts by weight of cresol novolac resin acrylic acid adduct, 2-methyl-1- (4- (methylthio) phenyl) -2 -7 parts by mass of morpholinopropan-1-one, 1 part by mass of 2,4-diethylthioxanthone, 2 parts by mass of melamine, 1 part by mass of phthalocyanine green, 10 parts by mass of talc, 43 parts by mass of barium sulfate, 21 parts by mass of silicon oxide, 40 parts by mass of triglycidyl isocyanurate and carbitol acetate were kneaded using a three-roll mill to prepare a photosensitive composition.
The obtained photosensitive composition solution was applied to the entire surface of the flexible substrate by screen printing in the same manner as in Example 1, and dried at 80 ° C. for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Comparative Example 3)
-Fabrication of flexible printed circuit board-
25 parts by mass of unsaturated group-containing polycarboxylic acid resin synthesized in Comparative Synthesis Example 3, 10 parts by mass of photosensitive polyamide resin synthesized in Comparative Synthesis Example 3, 2-methyl-1 [4- (methylthio) phenyl] -2- Morpholino-propan-1-one 4.5 parts by weight 2,4-diethylthioxanthone 0.5 parts by weight, melamine 4 parts by weight, phthalocyanine green 1 part by weight, silica 20 parts by weight, precipitated barium sulfate 15 parts by weight, epoxy Three roll mills containing 12 parts by mass of resin (ESLV-80XY, manufactured by Nippon Steel Chemical Co., Ltd.), 5 parts by mass of resin containing acrylate group and epoxy group synthesized in Comparative Synthesis Example 3, and 3 parts by mass of dipentaerythritol hexaacrylate Were kneaded to prepare a photosensitive composition.
The obtained photosensitive composition solution was applied to the entire surface of the flexible substrate by screen printing in the same manner as in Example 1, and dried at 80 ° C. for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

(Comparative Example 4)
-Fabrication of flexible printed circuit board-
13.36 parts by mass of benzylamine-modified resin synthesized in Comparative Synthesis Example 4, 4.59 parts by mass of dipentaerythritol hexaacrylate, 3.06 parts by mass of bifunctional acrylic monomer (R712, manufactured by Nippon Kayaku Co., Ltd.), bis (2 , 4,6-trimethylbenzoyl) -phenylphosphine oxide (manufactured by Ciba Specialty Chemicals) 1.98 parts by mass, 2 parts by mass of hexamethoxymethylmelamine (MW30HM, manufactured by Sanwa Chemical Co., Ltd.), F780F (Dainippon Ink Chemical Co., Ltd.) Kogyo Co., Ltd.) 30 mass% methyl ethyl ketone solution 0.066 mass part, phthalocyanine green dispersion (concentration in 10 mass% methoxypropanol) 1.0 mass part, hydroquinone monomethyl ether 0.024 mass part, and barium sulfate dispersion 24.75 parts by mass using a three-roll mill And kneaded to prepare a photosensitive composition.
The obtained photosensitive composition solution was applied to the entire surface of the flexible substrate by screen printing in the same manner as in Example 1, and dried at 80 ° C. for 30 minutes to form a photosensitive layer having a dry film thickness of 35 μm. Next, exposure and development were performed in the same manner as in Example 1 to produce a flexible printed circuit board.

  About the obtained flexible wiring printed circuit board of Examples 1-13 and Comparative Examples 1-4, various characteristics were evaluated as follows. The results are shown in Tables 3 and 4.

<Development evaluation>
The surface properties after development of each of the obtained flexible printed circuit boards were evaluated according to the following criteria by visual observation.
〔Evaluation criteria〕
○: The composition was completely removed after development in the non-image area.
Δ: There is a slight residue in the non-image area.
X: There is a residue that cannot be developed.

<Evaluation of adhesion>
In accordance with JIS K5400, 100 cross sections having a 1 mm width were prepared on each flexible wiring printed board, a peel test (cross cut test) was performed using a cellophane tape, and the following criteria were evaluated.
〔Evaluation criteria〕
○: 90 or more of 100 sites do not peel off.
(Triangle | delta): More than 50 places and less than 90 places do not peel in 100 places.
X: 0 or more and less than 50 places in 100 places do not peel.

<Evaluation of solder heat resistance>
A rosin flux was applied to each flexible printed circuit board and immersed in a solder bath at 260 ° C. for 10 seconds. After repeating this operation 6 times, the appearance of the flexible printed circuit board was evaluated according to the following criteria.
〔Evaluation criteria〕
○: There is no peeling or swelling in the external appearance, and there is no solder diving.
X: There exists peeling, a swelling, or the dive of solder.

<Pressure-resistant cooker test (PCT)>
Each flexible printed circuit board was allowed to stand in water vapor at 121 ° C. and 2 atm for 96 hours, and then the above cross-cut test was performed and evaluated according to the following criteria.
〔Evaluation criteria〕
○: 90 or more of 100 sites do not peel off.
(Triangle | delta): More than 50 places and less than 90 places do not peel in 100 places.
X: 0 or more and less than 50 places in 100 places do not peel.

<Folding resistance>
Each photosensitive composition of Examples 1 to 13 and Comparative Examples 1 to 4 is applied to a bar coating method or a non-adhesive two-layer flexible substrate made of a rolled copper foil (thickness = 35 μm) on a polyimide substrate (thickness = 25 μm). A photosensitive layer was formed by coating by screen printing. Next, after exposure at 500 mJ / cm ² , a cured film (thickness = 35 μm) is formed by heating at 160 ° C. for 2 hours, and using VCM FLEX TEESTER (IPC-FC241C, JIS-C5016), temperature = room temperature, The bending life (times) from when bending was performed to cracking copper was evaluated under the conditions of frequency = 25 Hz, stroke = 25 mm, and radius of curvature = 2 mm.

The photosensitive composition of the present invention has excellent developability, solder heat resistance, folding resistance, and pressure cooker resistance, greatly improves the flexibility of the cured film, mobile phones having moving parts, various in-vehicle devices, etc. It is used suitably for preparation of a flexible printed wiring board.

Claims (18)

A photosensitive composition comprising at least (A) a polyurethane resin having a carboxyl group, (B) a polymerizable compound, (C) a photopolymerization initiator, and (D) a thermal crosslinking agent. (A) A polyurethane resin having a carboxyl group reacts with a diisocyanate compound represented by the following structural formula (I) and a diol compound represented by either the following structural formula (II) or the following structural formula (III). The photosensitive composition according to claim 1, wherein the photosensitive composition is used.
However, 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 to} R ⁵ may be the same as or different from each other, and represent a divalent hydrocarbon group. Ar represents a trivalent aromatic hydrocarbon group. R ^{1 to} R ⁵ and Ar may be further substituted with a substituent, and two or three adjacent R ² , R ³ , R ⁴ and R ⁵ may be linked to form a ring. (A) The photosensitive composition in any one of Claim 1 to 2 whose acid value of the polyurethane resin which has a carboxyl group is 80-300 mgKOH / g. (D) The thermal crosslinking agent is at least one selected from an epoxy resin compound, an oxetane compound, a polyisocyanate compound, a compound obtained by reacting a polyisocyanate compound with a blocking agent, and a melamine derivative. The photosensitive composition in any one of Claim 3 to 3. The photosensitive composition in any one of Claim 1 to 4 used for manufacture of a flexible wiring printed circuit board. A photosensitive composition according to any one of claims 1 to 5 is applied to a surface of a substrate, dried to form a photosensitive layer, and then exposed and developed. Pattern formation method. The photosensitive layer modulates the light from the light irradiating means by the light modulating means having n picture elements for receiving and emitting the light from the light irradiating means. 7. The pattern forming method according to claim 6, wherein exposure is performed with light passing through a microlens array in which microlenses having aspherical surfaces capable of correcting aberrations are arranged. The photosensitive layer modulates the light from the light irradiation means by the light modulation means having n picture elements for receiving and emitting the light from the light irradiation means, and then the light from the peripheral part of the picture elements. The pattern forming method according to claim 6, wherein exposure is performed with light that has passed through a microlens array in which microlenses having a lens opening shape that does not allow incidence of light are arranged. The pattern forming method according to claim 8, wherein the microlens has an aspherical surface capable of correcting aberration due to distortion of the exit surface in the pixel portion. The pattern forming method according to any one of claims 7 to 9, wherein the aspherical surface is a toric surface. The pattern forming method according to claim 8, wherein the lens opening shape is circular. 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 light modulation means is capable of controlling any less than n number of pixel parts arranged continuously from n number of picture element parts according to pattern information. The pattern formation method in any one of. 14. The pattern forming method according to claim 7, wherein the light modulation means is a spatial light modulation element. The pattern forming method according to claim 14, wherein the spatial light modulation element is a digital micromirror device (DMD). The light irradiating means includes a plurality of lasers, a multimode optical fiber, and a collective optical system for condensing and coupling the laser beams respectively emitted from the plurality of lasers to the multimode optical fiber. 16. The pattern forming method according to any one of items 7 to 15. The pattern forming method according to claim 16, wherein the wavelength of the laser beam is 395 to 415 nm. A permanent pattern formed by the pattern forming method according to any one of claims 6 to 17.