TWI570513B - And a method for forming a photosensitive resin composition and a circuit pattern - Google Patents

Description

Photosensitive resin composition and method for forming circuit pattern

The present invention relates to a photosensitive resin composition which can be developed by an aqueous alkaline solution, and a circuit pattern forming method using the photosensitive resin composition. More specifically, the present invention relates to a metal foil which is suitable for the production of a printed wiring board, the manufacture of a flexible printed wiring board, the manufacture of an IC (Integrated Circuit) wafer mounting lead frame, and the manufacture of a metal mask. Precision processing; semiconductor package manufacturing such as BGA (Ball Grid Array), CSP (Chip Scale Package); TAB (Tape Automated Bonding) and COF (Chip On Film) Manufacture of semiconductor tapes, including the semiconductor chip mounted on a film-shaped micro-wiring board; manufacture of semiconductor bumps; ITO (Indium Tin Oxide) electrodes in the field of flat panel displays A photosensitive resin composition for a resist pattern produced by a member such as an address electrode or an electromagnetic wave mask, and a circuit pattern forming method using the photosensitive resin composition.

Previously, the manufacture of printed wiring boards, precision machining of metals, and the like were produced by photolithography. The photosensitive resin composition used in the photolithography method is classified into a composition of a negative type and a positive type. The photolithography method using a negative photosensitive resin composition is carried out, for example, by applying a negative photosensitive resin composition onto a substrate, performing pattern exposure, and performing exposure of the photosensitive resin composition. Polymerization hardening. Then, the unexposed portion is removed by the developer to form a resist pattern on the substrate. Further, performing etching or plating treatment After the conductor pattern is formed, the resist pattern is peeled off from the substrate, thereby forming a conductor pattern on the substrate.

In the photolithography method, when the photosensitive resin composition is applied onto a substrate, any one of the following methods is used: (1) a method of applying a photoresist solution onto a substrate and drying it, and ( 2) A photosensitive resin layer obtained by using a layered support and a layer containing a photosensitive resin composition (hereinafter referred to as "photosensitive resin layer") and a protective layer as needed, and a photosensitive resin layer A method of laminating on a substrate. In the manufacture of printed wiring boards, the latter method is used in most cases.

Hereinafter, a method of manufacturing a printed wiring board using the above-described photosensitive resin laminate will be briefly described.

First, the protective layer is peeled off from the photosensitive resin laminate. Then, the photosensitive resin layer and the support volume layer are formed on the substrate such as a copper foil laminate using a bonding machine in the order of the substrate, the photosensitive resin layer, and the support. Then, the photosensitive resin layer is exposed through a mask having a desired wiring pattern, and the exposed portion is subjected to polymerization hardening. Then, the above support is peeled off. Then, a resist pattern is formed on the substrate by dissolving or dispersing the unexposed portion of the photosensitive resin layer with a developing solution.

As the protective layer, for example, a polyethylene film or the like is preferably used; as the support, for example, a polyethylene terephthalate film or the like is preferably used; and as the developer, for example, an aqueous solution having a weak alkalinity is preferably used. Wait.

The step of dissolving or dispersing the photosensitive resin layer in the unexposed portion by the developer is referred to as a development step. Each time the development step is repeated, the amount of dissolution of the unexposed portion of the photosensitive resin composition is increased in the developer. Therefore, when the development step is repeated, the foaming property of the developer tends to increase. The foamability of the developer significantly reduces the work efficiency of the development step.

Next, a resist pattern formed by the above development step is used as a protective mask. An etching process or a pattern plating process is performed. Finally, a substrate having a conductor pattern (i.e., a printed wiring board) is produced by peeling the resist pattern from the substrate.

In recent years, with the miniaturization and weight reduction of electronic equipment, the line/gap (L/S) of wiring has been miniaturized and densified. Further, the demand for a build-up substrate having a multilayer wiring structure is also increased. In the build-up method, since a technique of accurately aligning the position between the multilayer substrates is required, a photosensitive resin layer capable of applying a direct imaging (DI, Derect Image) method excellent in alignment accuracy is becoming mainstream. Therefore, high sensitivity and high resolution of the photosensitive resin are required.

In this regard, Patent Literatures 1 and 2 disclose photosensitive resin compositions containing a specific alkali-soluble polymer, a monomer, and a photopolymerizable initiator, and the photosensitive resin composition is described. The above-described high sensitivity and high resolution are achieved. Patent Document 3 discloses a method of using a polyalkylene alcohol as an additive of a photosensitive resin composition in order to suppress foaming property of a developing solution.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2009/147913

[Patent Document 2] International Publication No. 2010/098175

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2012-159651

In order to cope with the miniaturization and high density of wiring, it is required to stably produce the final line width of the etched conductor line (for example, copper wire). For this reason, the resist width after development is required to be relatively stable. However, at the bottom of the resist after development, a minute skirt-like bottom phenomenon called "resist crotch portion" is often seen (refer to Fig. 1). Further, the presence of the resist crotch portion is a factor that makes the width of the conductor line after etching uneven. Further, regarding the existence of the resist crotch portion, in the method of forming a conductor pattern by pattern plating, the obtained conductor is also obtained. The pattern has a large influence on the adhesion of the substrate. These phenomena are particularly prominent in the DI type exposure method used in recent years, and have become a new problem that comes with the advancement of technology.

Regarding the mechanism by which the generation of the resist crotch in the DI exposure becomes apparent, it is considered as follows. However, the invention is not limited to the following theories.

The DI exposure system utilizes the exposure mode of the scanning of the laser spot. The intensity of the laser spot is based on a Gaussian distribution. Therefore, a region where the amount of exposure is small (a weak exposure region) is generated at both end portions of the exposure pattern. The hardened resist in the weakly exposed region is partially dissolved in the subsequent development step because the developer resistance is lowered. It is considered that since the dissolved residue at this time is deposited on the bottom of the resist and deposited, a resist crotch portion is generated.

This weakly exposed area is a unique problem in the multiple exposure DI of the point of use. More importantly, since the width of the weak light region is determined by a fixed value, the narrower the line width of the design becomes, the more the problem becomes superficial. In order to improve the resolution, each exposure machine manufacturer is working to improve the resolution of the laser spot diameter and the point. However, the current situation is that the performance of the exposure machine does not follow the requirements of the high-performance printed circuit board.

In order to suppress the foaming property in the development step, it is reported that the polyalkylene alcohol as an antifoaming agent is added to the photosensitive resin composition in the above-mentioned Patent Document 3 (JP-A-2012-159651). The method. However, according to the technique of Patent Document 3, since the density of the monomer is reduced by the addition of the antifoaming agent, the efficiency of photopolymerization caused by exposure is lowered, and the sensitivity tends to be lowered.

Therefore, an object of the present invention is to provide a photosensitive resin composition for direct imaging which has stability of a conductor line width after etching or adhesion of a conductor wire after plating, or both of them, and use of the photosensitivity A method of forming a circuit pattern of a resin composition.

In order to solve the above problems, the inventors of the present invention have conducted research and repeated experiments. As a result, it was found that the above problems can be solved by the following technical methods, thereby completing Cost invention.

The present invention discloses the following embodiments.

[1] A photosensitive resin composition comprising (A) an alkali-soluble polymer: 40 to 80% by mass, (B) a photopolymerization initiator: 0.1 to 20% by mass, and (C) a compound having an ethylenic double bond: 5 to 50% by mass, and a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate so that the position of the focus at the time of exposure is from the surface of the substrate. The resist pattern width of the resist pattern obtained by exposure and development under the condition that the substrate is shifted by 200 μm in the thickness direction of the substrate is 0.01 μm to 3.5 μm, and is used for direct imagewise exposure.

[2] The photosensitive resin composition according to the above [1], wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to have a Stouffer 21 grade When the exposure sheet is exposed as a mask, and the exposure amount of the highest residual film level at the time of development is 6 levels, the average of the ethylenic double bonds in the compound (C) is exposed. When the number is Q, and the reaction rate of the ethylenic double bond in the compound (C) after the above exposure is P, the value of P × Q / 100 is 0.7 or more.

[3] The photosensitive resin composition according to the above [1] or [2], wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to introduce Stufe 21 When the exposure film is exposed as a mask, and the exposure amount of the highest residual film level at the time of development is 1/10 of the exposure amount, the photosensitive resin layer is exposed to the above-mentioned (C) compound. The average number of the ethylenic double bonds is set to Q, and the value of P'×Q/100 when the reaction rate of the ethylenic double bond in the above (C) compound after the above exposure is taken as P' It is 0.3 or more.

[4] The photosensitive resin composition according to any one of the above [1], wherein the weight average Tg ^total of the Tg of the (A) alkali-soluble polymer is 30 ° C or more and 125 ° C or less. .

[5] The photosensitive resin composition according to any one of the above [1], wherein the compound (C) contains a compound having three or more methacryl groups in one molecule.

[6] The photosensitive resin composition according to any one of the above [1], wherein the compound (C) contains a compound having four or more methacryl groups in one molecule.

The photosensitive resin composition of any one of the above-mentioned (C) containing the compound represented by following formula (IV),

In the formula, n ₁ , n ₂ , n ₃ , and n ₄ each independently represent an integer of 1 to 25, and n ₁ + n ₂ + n ₃ + n ₄ is an integer of 9 to 60, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, and R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkylene group, and when a plurality of R ₅ , R ₆ , R ₇ and R ₈ are respectively present, The plurality of R ₅ , R ₆ , R ₇ , and R ₈ may be the same or different from each other}.

[8] The photosensitive resin composition according to the above [7], wherein, in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of from 15 to 40.

[9] The photosensitive resin composition according to the above [7], wherein, in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of 15 to 28.

[10] The photosensitive resin composition according to any one of the above [1], wherein the (B) photopolymerization initiator comprises an acridine compound.

[11] The photosensitive resin composition according to any one of the above [1] to [10] further comprising a halogen compound.

[12] The photosensitive resin composition according to any one of the above [1], wherein the (B) photopolymerization initiator comprises N-phenylglycine or a derivative thereof.

[13] The photosensitive resin composition according to any one of the above [1], wherein the (A) alkali-soluble polymer has an aromatic hydrocarbon group.

[14] A photosensitive resin composition comprising (A) an alkali-soluble polymer: 40 to 80% by mass, (B) a photopolymerization initiator: 0.1 to 20% by mass, and (C) A compound having an ethylenic double bond: 5 to 50% by mass, and the above compound (C) contains a compound having 3 or more methacryl groups in one molecule.

[15] The photosensitive resin composition according to the above [14], wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to have a Stuart 21-stage exposure meter as When the mask is subjected to exposure, and the exposure amount of the highest residual film level at the time of development is 6 levels, the average number of ethylenic double bonds in the compound (C) is set. Q, and the value of P × Q / 100 in the case where the reaction rate of the ethylenic double bond in the compound (C) after the above exposure is P is 0.7 or more.

[16] The photosensitive resin composition according to the above [14] or [15], wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to introduce Stufe 21 The exposure sheet is exposed as a mask, and then the exposure amount of the highest residual film level at the time of development is 1/10 of the exposure amount is performed on the photosensitive resin layer. At the time of exposure, the average number of ethylenic double bonds in the above (C) compound is set to Q, and the reaction rate of the ethylenic double bond in the above (C) compound after the above exposure is set to P' In the case, the value of P'×Q/100 is 0.3 or more.

The photosensitive resin composition as described in any one of the above-mentioned [14], wherein the compound (C) contains a compound having four or more methacryl groups in one molecule.

[18] The photosensitive resin composition according to any one of the above [14], wherein the compound (C) contains a compound represented by the following formula (IV),

In the formula, n ₁ , n ₂ , n ₃ , and n ₄ each independently represent an integer of 1 to 25, and n ₁ + n ₂ + n ₃ + n ₄ is an integer of 9 to 60, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, and R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkylene group, and when a plurality of R ₅ , R ₆ , R ₇ and R ₈ are respectively present, The plurality of R ₅ , R ₆ , R ₇ , and R ₈ may be the same or different from each other}.

[19] The photosensitive resin composition according to the above [18], wherein in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of from 15 to 40.

[20] The photosensitive resin composition according to the above [18], wherein, in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of 15 to 28.

[21] The photosensitive resin composition according to any one of the above [14], wherein the (B) photopolymerization initiator comprises an acridine compound.

The photosensitive resin composition as described in any one of the above [14] to [21] further containing a halogen compound.

[23] The photosensitive resin composition according to any one of the above [14], wherein the (B) photopolymerization initiator comprises N-phenylglycine or a derivative thereof.

[24] The photosensitive resin composition according to any one of the above [14], wherein the (A) alkali-soluble polymer has an aromatic hydrocarbon group.

The photosensitive resin composition of any one of the above-mentioned (A) alkali-soluble polymer, wherein the weight average Tg ^total of the Tg of the alkali-soluble polymer is 30 ° C or more and 125 ° C or less. .

[26] The photosensitive resin composition as described in any one of [14] to [25] which is used for direct imagewise exposure.

[27] A method of forming a circuit pattern, comprising the steps of: forming a layer of the photosensitive resin composition according to any one of the above [1] to [26] on a substrate; a step of exposing and developing a layer of the resin composition to form a resist pattern; and a step of etching or plating the substrate on which the resist pattern is formed.

[28] The method according to [27] above, wherein the exposure is performed by direct imagewise exposure.

According to the present invention, by suppressing the generation of the resist crotch portion, it is possible to provide a wide stability of the conductor wire (for example, copper wire) after etching, and excellent adhesion of the conductor wire after plating, and can be suitably applied to utilization. a photosensitive resin composition formed by a circuit pattern of a direct imaging method, And a method of forming a circuit pattern using the photosensitive resin composition.

Fig. 1 is a schematic cross-sectional view for explaining the definition of the width of a resist crotch portion.

Hereinafter, the form for carrying out the invention (hereinafter, simply referred to as "the embodiment") will be described in detail. The present invention is not limited to the embodiments described below, and various modifications can be made without departing from the spirit and scope of the invention.

<Photosensitive Resin Composition>

In one embodiment, the photosensitive resin composition (photosensitive resin composition for direct image formation) is characterized in that it contains (A) an alkali-soluble polymer: 40 to 80% by mass, and (B) photopolymerization initiation The agent: 0.1 to 20% by mass, and (C) a compound having an ethylenic double bond: 5 to 50% by mass, and a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate. The resist portion width of the resist pattern obtained by exposing and developing the position of the focus at the time of exposure from the substrate surface in the thickness direction of the substrate by 200 μm is 0.01 μm to 3.5 μm. And for direct imaging exposure.

Another embodiment provides a photosensitive resin composition comprising (A) an alkali-soluble polymer: 40 to 80% by mass, (B) a photopolymerization initiator: 0.1 to 20% by mass, and ( C) A compound having an ethylenic double bond: 5 to 50% by mass, and the above compound (C) contains a compound having 3 or more methacryl groups in one molecule.

The photosensitive resin composition for direct imagewise exposure of the present invention is a composition in which the resist pattern obtained by exposure and development in the above conditions forms the specific resist crotch width. A photosensitive resin layer having a thickness of 25 μm including a photosensitive resin composition is formed on the surface of the substrate, and the position of the focus at the time of exposure is exposed from the surface of the substrate to the inside of the substrate by 200 μm in the thickness direction of the substrate. The width of the resist portion of the resist pattern obtained by development is 0.01 μm to 3.5 μm, which contributes to reducing the unevenness of the width of the conductor line after etching and improving the adhesion of the conductor line after plating. condition. It is advantageous from the viewpoint of improving the adhesion of the hardened resist to the width of the resist portion of 0.01 μm or more; the value of 3.5 μm or less reduces the unevenness of the width of the conductor line after etching, and improves plating. It is advantageous from the viewpoint of the adhesion of the conductor wires after application. The resist crotch portion width is preferably 0.02 μm or more, more preferably 0.03 μm or more, more preferably 2.5 μm or less, still more preferably 2.0 μm or less, further preferably 1.5 μm or less, and particularly preferably 1.2 μm or less. Preferably, it is 1 μm or less.

The more specific order of the above exposure and development is based on the method described in the item of [Example] or the method equivalent to those skilled in the art.

The above-described specific resist portion width is understood to be realized by using each of the components (A) to (C) at a specific ratio and, for example, a method exemplified below (not limited thereto). Hereinafter, each component contained in the photosensitive resin composition of the present embodiment will be described in order.

<(A) alkali soluble polymer>

In the present embodiment, the (A) alkali-soluble polymer is a polymer which can be dissolved in an alkaline aqueous solution. For example, a vinyl polymer containing a carboxyl group is preferable, and a monomer selected from the group consisting of (meth)acrylic acid, (meth)acrylate, (meth)acrylonitrile, (meth)acrylamide, and the like is preferable. Copolymer.

(A) The alkali-soluble polymer preferably has a carboxyl group and has an acid equivalent of from 100 to 600. The acid equivalent means the mass of the gram unit of the alkali-soluble polymer having 1 equivalent of a carboxyl group. on From the viewpoint of improving the development resistance, the resolution, and the adhesion, the acid equivalent is preferably 100 or more. On the other hand, from the viewpoint of improving developability and peelability, it is preferred to set the acid equivalent. 600 or less. The measurement of the acid equivalent can be carried out by a potentiometric titration method using a 0.1 mol/L aqueous sodium hydroxide solution using a titration apparatus (for example, manufactured by Hiranuma Sangyo Co., Ltd., Hirohyo Automatic Titration Apparatus (COM-555)). The acid equivalent of the (A) alkali-soluble polymer is more preferably from 250 to 450.

The (A) alkali-soluble polymer preferably has a weight average molecular weight of 5,000 or more and 500,000 or less. From the viewpoint of the properties of the developed coacervate, the edge meltability of the photosensitive resin laminate, and the properties of the unexposed film such as dicing wafer properties, the weight average molecular weight is preferably 5,000 or more. From the viewpoint of improving the solubility in the developer, the weight average molecular weight is preferably 500,000 or less. The edge melting property is a property of suppressing a phenomenon in which the photosensitive resin composition layer overflows from the end surface of the roll when the photosensitive resin laminated body is wound into a roll shape. The dicing wafer property is a property of suppressing the phenomenon of wafer flying out when the unexposed film is cut by a cutter. If the dicing property is poor, there is a problem that the scattered wafer is attached to, for example, the upper surface of the photosensitive resin laminate, and the wafer is transferred onto the mask in the subsequent exposure step to cause a defect. The weight average molecular weight of the alkali-soluble polymer (A) is more preferably 5,000 or more and 300,000 or less, and still more preferably 10,000 or more and 200,000 or less.

Preferably, the (A) alkali-soluble polymer has an aromatic hydrocarbon group.

When the (A) alkali-soluble polymer has an aromatic hydrocarbon group, it is possible to improve the resolution and adhesion, reduce the amount of aggregates generated during development, and improve the etching resistance.

An aromatic hydrocarbon group can be introduced into the (A) alkali-soluble polymer by using an aromatic vinyl compound or a (meth) acrylate compound having a benzyl group as part of the monomer used in the synthesis.

(A) The alkali-soluble polymer can be obtained by copolymerizing one or two or more monomers selected from the following two types of monomers.

The first monomer is a carboxylic acid or anhydride having a polymerizable unsaturated group in the molecule. For example, (meth)acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, a maleic acid half ester, etc. are mentioned. Especially preferred is (meth)acrylic acid. Here, the term "(meth)acrylic" means acrylic acid or methacrylic acid.

(A) The copolymerization ratio of the first monomer in the alkali-soluble polymer can be easily calculated from the value of the acid equivalent required in the alkali-soluble polymer. (A) The copolymerization ratio of the first monomer in the alkali-soluble polymer is preferably from 10 to 50% by mass based on the total mass of all the monomer components. From the viewpoint of exhibiting good developability, controlling edge meltability, and the like, it is preferred to set the copolymerization ratio to 10% by mass or more. In view of the viewpoint of improving the resolution and suppressing the generation of the resist, the copolymerization ratio is preferably 50% by mass or less, and more preferably 30% by mass. Hereinafter, it is more preferably 25% by mass or less, and still more preferably 20% by mass or less.

The second single system is a monomer that is non-acidic and has at least one polymerizable unsaturated group in the molecule. For example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, (methyl) ) isobutyl acrylate, tert-butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, Benzyl (meth)acrylate, ester of vinyl alcohol; vinyl acetate; (meth)acrylonitrile; aromatic vinyl compound. Examples of the aromatic vinyl compound include styrene and a styrene derivative.

As the second monomer, among the above, methyl (meth)acrylate, n-butyl (meth)acrylate, styrene, a styrene derivative, and benzyl (meth)acrylate are preferable. Among these, styrene, styrene derivatives, and (A) are particularly preferable in terms of improving resolution, improving adhesion, or developing cohesiveness (less amount of aggregates) and etching resistance. Base) benzyl acrylate.

As the copolymer component in the (A) alkali-soluble polymer, an aromatic monomer such as an aromatic vinyl compound or a (meth) acrylate compound having a benzyl group can be used. About (A) base The copolymerization ratio of the compound of the aromatic monomer in the soluble polymer is preferably from 20 to 85% by mass based on the total mass of all the monomer components. The copolymerization ratio is preferably 20% by mass or more, and more preferably 25% by mass, from the viewpoints of improving resolution and adhesion, suppressing generation of aggregates during development, and improving etching resistance. The above is more preferably 30% by mass or more, and particularly preferably 40% by mass or more. From the viewpoint of exhibiting moderate developability, it is preferred to set the copolymerization ratio to 85% by mass or less. In view of the cost, the aromatic vinyl compound is more preferable, and among the alkali-soluble polymers (A), the copolymerization ratio is preferably 20 based on the total mass of all the monomer components. ~70% by mass. From the viewpoint of improving the resolution, improving the adhesion, or exhibiting good development cohesiveness, etching resistance, and the like, the copolymerization ratio is preferably 20% by mass or more, and more preferably 25% by mass. % or more is further preferably 30% by mass or more, and particularly preferably 40% by mass or more. From the viewpoint of exhibiting moderate developability and flexibility of the cured film, the copolymerization ratio is preferably 70% by mass or less, and more preferably 60% by mass or less. When the viewpoint is emphasized, the copolymerization ratio of the aromatic vinyl compound is more preferably 20 to 50% by mass, particularly preferably 20 to 30% by mass.

In one embodiment, examples of the aromatic vinyl compound include styrene and a styrene derivative. Examples of the styrene derivative include oxystyrene, hydroxystyrene, ethoxylated styrene, alkylstyrene, and haloalkylstyrene.

(A) The alkali-soluble polymer is preferably a copolymer comprising a styrene or a styrene derivative, methyl (meth)acrylate, and a monomer mixture of (meth)acrylic acid as a copolymerizable monomer.

In the above, in order to obtain excellent resolution, the copolymerization ratio of the aromatic vinyl compound is preferably 40 to 60% by mass based on the total mass of all the monomer components. It is preferred to contain a styrene or styrene derivative, methyl (meth)acrylate, and/or (meth)acrylic acid as a copolymerizable monomer in this case.

In one embodiment, the weight average Tg ^total of the Tg of the (A) alkali-soluble polymer in the photosensitive resin composition may be in the range of 30 to 125 ° C, preferably 50 to 110 ° C, more preferably 50. ~105 ° C, and more preferably 50 to 90 ° C. From the viewpoint of controlling edge meltability, it is preferable to set the weight average of Tg to 30 ° C or higher, and it is preferable to set 110 ° C from the viewpoint of suppressing generation of the resist crotch portion. the following. The weight average Tg ^total of Tg in the present invention is a value obtained by the following formula (Fox formula): Tg ^total = Σ _i (W _i × Tg _i ) / W ^total

Here, W _i is the solid mass of each alkali-soluble polymer, Tg _i is the glass transition temperature obtained by the Fox formula for each alkali-soluble polymer, and W ^total is the total value of the solid mass of each alkali-soluble polymer. }. Here, when the glass transition temperature Tg _i is determined by the Fox equation for each alkali-soluble polymer, it is necessary to include the Tg of the homopolymer of the copolymerizable monomer forming each alkali-soluble polymer. In the present invention, literature values (Brandrup, J. Immergut, EH ed., Polymer handbook, Third edition, John Wiley & sons, 1989, Chapter VI "Glass transition temperatures of polymers", p209) are used as the values.

The Tg _i of each of the copolymerized monomers used in the calculations in the examples is shown in Table 4.

The mechanism for suppressing the resist crotch portion during DI exposure by using the (A) alkali-soluble polymer having the above composition is considered as follows. However, the invention is not limited to the following theories.

In the DI exposure, a weak exposure area is produced on both sides of the exposure pattern. The reaction rate of the resist in the weakly exposed region is lowered. Thereby, the developer resistance of the hardened resist in this region is lowered, so that it is partially dissolved in the subsequent development step. It is presumed that since the dissolved residue at this time is deposited on the bottom of the resist and deposited, a resist crotch portion is generated.

Therefore, in order to suppress the generation of the resist crotch portion, it is considered that it is necessary to efficiently harden the monomer in the resist in the weakly exposed region. It is believed that the reaction rate of the monomer is affected by the diffusion speed of the monomers, and the diffusion rate is limited by the free volume in the resist.

In view of the above, it is considered that by designing the composition and structure of the (A) alkali-soluble polymer in such a manner that the free volume in the resist is increased, the reaction rate of the monomer can be increased to suppress the resist in the weakly exposed region. Crotch.

As an indicator of the free volume, a glass transition temperature Tg can usually be used. The ratio of the Tg free volume to the total volume of the polymer begins to increase. Therefore, it is considered that at a temperature higher than Tg, the free volume increases in proportion to the temperature difference from Tg.

Under the same temperature condition, the higher the Tg of the substance, the smaller the free volume, and the lower the Tg, the larger the free volume. Therefore, it is considered that the resist composition having a high Tg is likely to cause a decrease in the monomer reaction rate, so that a resist crotch portion is formed, and a resist composition having a low Tg suppresses the generation of the resist crotch portion.

For this reason, it is preferable that the weight average Tg ^total of the Tg of the (A) alkali-soluble polymer is low, but it is preferable to control the edge meltability when the Tg ^{total is} high. Considering the balance of these meltability, the results can be exemplified as the preferred range of Tg ^total .

In the embodiment, the amount of the (A) alkali-soluble polymer in the photosensitive resin composition is preferably set to 100% by mass based on the total mass of the solid content of the photosensitive resin composition. The range of 40 to 80% by mass, more preferably 50 to 70% by mass. It is advantageous from the viewpoint of controlling the edge meltability from the viewpoint of the blending amount of 40% by mass or more. On the other hand, it is advantageous from the viewpoint of controlling the development time by setting the blending amount to 80% by mass or less.

<(B) Photopolymerization initiator>

In the embodiment of the present invention, as the (B) photopolymerization initiator, various materials which can be used as a photopolymerization initiator of the photosensitive resin can be used.

As the photopolymerization initiator (B) in the present embodiment, for example, a group selected from the group consisting of an acridine compound, an N-aryl-α-amino acid compound, and a triaryl imidazole dimer can be used. More than one type. The acridine compound is preferred from the viewpoint of exhibiting a high degree of sensitivity and at the same time achieving high sensitivity and suppression of the generation of the crotch portion of the resist; From the viewpoint of more reliably suppressing the generation of the crotch portion of the resist, a triaryl imidazole dimer is preferred.

Examples of the acridine compound include 1,7-bis(9,9'-acridinyl)heptane, 9-phenyl acridine, 9-methyl acridine, 9-ethyl acridine, and 9 -Chloroethyl acridine, 9-methoxy acridine, 9- Ethyl acridine, 9-(4-methylphenyl)acridine, 9-(4-ethylphenyl)acridine, 9-(4-n-propylphenyl)acridine, 9-(4 -n-butylphenyl)acridine, 9-(4-t-butylphenyl)acridine, 9-(4-methoxyphenyl)acridine, 9-(4-ethoxyphenyl) Acridine, 9-(4-ethylmercaptophenyl)acridine, 9-(4-dimethylaminophenyl)acridine, 9-(4-chlorophenyl)acridine, 9-(4- Bromophenyl)acridine, 9-(3-methylphenyl)acridine, 9-(3-tert-butylphenyl)acridine, 9-(3-acetamidophenyl)acridine, 9 -(3-dimethylaminophenyl)acridine, 9-(3-diethylaminophenyl)acridine, 9-(3-chlorophenyl)acridine, 9-(3-bromobenzene Acridine, 9-(2-pyridyl)acridine, 9-(3-pyridyl)acridine, and 9-(4-pyridyl)acridine. Among these, from the viewpoints of sensitivity, resolution, and availability, it is preferably 1,7-bis(9,9'-acridinyl)heptane or 9-phenylacridine.

Examples of the N-aryl-α-amino acid compound include N-phenylglycine, N-methyl-N-phenylglycine, and N-ethyl-N-phenylglycine. Wait. In particular, N-phenylglycine has a higher sensitizing effect and is preferred.

Examples of the triaryl imidazole dimer include 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer and 2-(o-chlorophenyl)-4,5-di(methoxy). Phenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole 2,4,5-triarylimidazole dimer such as 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer.

The acridine compound is highly sensitive compared to the triaryl imidazole dimer compound. Further, when a urethane compound is used as the (C) compound having an ethylenic double bond, it is preferable from the viewpoint of suppressing both foaming property and developing cohesiveness.

N-phenylglycine and its derivatives are preferred from the viewpoint of improving sensitivity. In particular, when N-phenylglycine or a derivative thereof is used in combination with an acridine compound, it is preferable to suppress the generation of the resist crotch more reliably.

In a preferred aspect, the (B) photopolymerization initiator preferably comprises one selected from the group consisting of an acridine compound, an N-phenylglycine, and an N-phenylglycine derivative. More than one species. The acridine compound preferably contains a compound selected from the following formula (I):

The 9-phenyl acridine represented by the following formula (II):

(wherein R ₁ represents an alkylene group having 1 to 12 carbon atoms)

One or more of the group consisting of the compounds represented. These compounds are advantageous from the standpoint of improving sensitivity in DI exposure. The carbon number of R ₁ in the formula (II) is from 1 to 12, which is advantageous from the viewpoint of solubility. The carbon number of R ₁ is more preferably 4 to 10.

As the acridine compound, 9-phenyl acridine represented by the above formula (I) is preferably used.

As the (B) photopolymerization initiator in the present embodiment, only a group selected from the group consisting of an acridine compound, N-phenylglycine or a derivative thereof, and a triaryl imidazole dimer can be used. One type or more may further contain a photopolymerization initiator other than the above.

Further examples of the (B) photopolymerization initiator include benzophenone and N,N'-tetramethyl-4,4'-dimethylaminobenzophenone (Michele). Ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2-benzyl-2 -Dimethylamino-1-(4-morpholinylphenyl)-butanone-1, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinyl-acetone -1 such as an aromatic ketone; 2-ethyl hydrazine, phenanthrenequinone, 2-tert-butyl fluorene, octamethyl hydrazine, 1,2-benzopyrene, 2,3-benzopyrene, 2-phenylindole, 2,3-diphenylanthracene, 1-chloroindole, 2-methylindole, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1 , 4-naphthoquinone, 2,3-dimethylhydrazine and the like; benzoin ether, benzoin ethyl ether, benzoin phenyl ether and other benzoin ether compounds; benzoin methyl ketal and other benzoin derivatives; Prime compound; 4,4'-bis(diethylamino)benzophenone; 1-phenyl-3-(4-t-butyl-styryl)-5-(4-third -Phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-t-butyl-phenyl)-pyrazoline, 1-phenyl-3- (4-biphenyl)-5-(4-trioctyl-phenyl)- A pyrazoline derivative such as a pyrazoline or the like.

(B) The photopolymerization initiator may be used alone or in combination of two or more.

When the mass of the solid content of the photosensitive resin composition is 100% by mass, the amount of the photopolymerization initiator (B) in the photosensitive resin composition is 0.1 to 20% by mass. The amount of the compounding amount is 0.1% by mass or more based on the viewpoint of obtaining an exposure pattern having a sufficient residual film ratio after development. On the other hand, the blending amount is 20% by mass or less based on the light sufficiently transmitted to the resist. The viewpoint of obtaining a high resolution of the underside of the agent and suppressing development cohesiveness in the developer. The preferred range of the blending amount is from 0.3 to 10% by mass.

In the case where the (B) photopolymerization initiator contains an acridine compound, the amount of the acridine compound is preferably 0.01% by mass to 5% by mass based on the total mass of the solid content of the photosensitive resin composition. . In terms of obtaining a good sense of sensitivity, it is preferred to adjust the tone. The amount of the amount is set to 0.01% by mass or more. The blending amount is more preferably 0.1% by mass or more, and particularly preferably 0.2% by mass or more. On the other hand, from the viewpoint of adjusting the shape of the resist to a rectangular shape and improving the hue stability of the photosensitive resin composition, the blending amount is preferably 5% by mass or less. The blending amount is more preferably 3% by mass or less, and particularly preferably 2% by mass or less.

In the case where the (B) photopolymerization initiator contains an N-aryl-α-amino acid compound, the N-aryl-α-amino acid is based on the total mass of the solid component of the photosensitive resin composition. The content of the compound is preferably 0.001% by mass to 5% by mass. From the viewpoint of obtaining good sensitivity, the blending amount is preferably 0.001% by mass or more. In particular, when the N-aryl-α-amino acid compound and the acridine compound are used in combination, it is preferable to suppress the generation of the resist crotch more reliably. The blending amount is more preferably 0.01% by mass or more, further preferably 0.05% by mass or more, and particularly preferably 0.1% by mass or more. On the other hand, from the viewpoint of improving the resolution and improving the hue stability of the photosensitive resin composition, the blending amount is preferably 5% by mass or less. The blending amount is more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less.

When the (B) photopolymerization initiator contains a triaryl imidazole dimer, the content of the triaryl imidazole dimer is preferably 0.1% by mass based on the total mass of the solid content of the photosensitive resin composition. 15% by mass. From the viewpoint of obtaining good sensitivity, it is preferred to set the blending amount to 0.1% by mass or more. The blending amount is more preferably 1% by mass or more, and particularly preferably 3% by mass or more. On the other hand, from the viewpoint of obtaining high resolution and suppressing cohesiveness in the developer, it is preferred to set the blending amount to 15% by mass or less. The blending amount is more preferably 10% by mass or less, and particularly preferably 6% by mass or less.

<(C) Compound having an ethylenic double bond>

In the embodiment of the present invention, the photosensitive resin composition contains (C) a compound having an ethylenic double bond. Preferable examples of the compound include a trifunctional or higher methacrylate group (three or more methacryl groups in one molecule) and a molecular weight of 500 g/mol. Above and 5,000 g/mol or less of compound (polyfunctional monomer). The compound (C) is more preferably a compound having a tetrafunctional or higher methacrylate group (four or more methacryl groups in one molecule).

Regarding the mechanism for suppressing the resist crotch portion in the DI exposure by using the above (C) compound, the following is considered. However, the invention is not limited to the following theories.

As described above, in the DI exposure, weak exposure regions are produced on both sides of the exposure pattern. Further, it is estimated that the reaction rate of the resist existing in the region is lowered, so that the developer liquid resistance is lowered to cause the resist crotch portion. Therefore, in order to suppress the generation of the resist crotch portion, it is necessary to increase the reaction rate of the (C) compound in the weakly exposed region, increase the crosslinking density, and improve the development liquid resistance.

In order to crosslink the resist, it is necessary to further react the other unreacted double bonds in the same monomer after reacting one of the double bonds of the polyfunctional monomer. Therefore, the (C) compound has a large amount of double bonds, and the less unreacted double bonds remaining after exposure, the more the crosslinking density is increased.

However, the polyfunctional monomer obtained by reacting the double bond once is introduced into the high molecular weight growth polymer chain. Therefore, in order to react two or more of the double bonds in the polyfunctional monomer molecule, the double bond that hangs to the growing polymer chain needs to react with other monomers or growing polymers. The steric hindrance of this reaction is large and unfavorable. In order to promote the reaction by mitigating the steric hindrance of such a reaction, it is necessary to lengthen the molecular chain between the double bonds in the (C) compound. Therefore, it is preferred that the molecular weight of the (C) compound is large. On the other hand, when the polymer having a too high molecular weight is increased, the reaction rate of the double bond of the compound (C) is increased, but the amount of the double bond in the composition is lowered, so that the crosslinking density is also lowered in this case. .

Therefore, in order to suppress the resist crotch portion during the DI exposure, it is considered to be particularly effective as a methacrylate monomer having a high molecular weight body and having a large amount of functional groups.

From this point of view, in the compound (C) in the present embodiment, there is a range of the optimum molecular weight and the number of functional groups. The molecular weight of the (C) compound is preferably 500 g/mol or more. 5,000 g/mol or less, more preferably 600 g/mol or more and 4,000 g/mol or less, further preferably 700 g/mol or more and 3,000 g/mol or less.

The number of the functional groups in the compound (C) is preferably a trifunctional or higher viewpoint from the viewpoint of improving the crosslinking density, improving the resolution and adhesion, and suppressing the generation of the resist crotch portion. More than 4 functional groups. From the viewpoint of controlling edge meltability, it is also preferably a trifunctional or higher functional group, and more preferably a tetrafunctional or higher functional group. In addition, from the viewpoint of the peeling property, it is preferably 10 or less, more preferably 6 or less, further preferably 5 or less, and particularly preferably 4 or less. Therefore, in order to exhibit an improvement in resolution, a suppression of generation of a resist crotch, control of edge meltability, and peeling properties at a high level, it is preferably tetrafunctional.

Further, from the viewpoint of the development resistance of the monomer crosslinked body, the methacrylate monomer having a low hydrolyzability is effective. The methacrylate monomer is excellent in terms of improvement in resolution and adhesion, suppression of generation of a resist crucible, and control of edge meltability.

In the embodiment of the present invention, the photosensitive resin composition preferably contains a compound represented by the following formula (III) as (C) a compound having an ethylenic double bond.

In the formula, n ₁ , n ₂ , and n ₃ are each independently an integer from 1 to 25, wherein n ₁ + n ₂ + n ₃ is an integer from 3 to 75, and R ₁ , R ₂ , and R ₃ are independent. Is an alkyl}.

In the general formula (V), the value of n ₁ + n ₂ + n ₃ is preferably 3 or more and 50 or less. From the viewpoint of suppressing the generation of the resist crotch portion, the viewpoint of imparting flexibility to the cured film, and the improvement of the puncture resistance of the cover film, it is preferable to set n ₁ +n ₂ +n ₃ to 3 or more. On the other hand, from the viewpoint of obtaining high resolution, adhesion, and good peeling properties, it is preferable to set n ₁ + n ₂ + n ₃ to 50 or less. A more preferable range of n ₁ + n ₂ + n ₃ is 6 or more and 40 or less, and further preferably a range of 9 or more and 30 or less.

Specific examples of the compound represented by the above formula (III) include trimethyl acrylate having an average of 3 moles of ethylene oxide added to the terminal of the hydroxyl group of trimethylolpropane, and trishydroxyl The terminal end of the hydroxyl group of methyl propane is added with an average of 9 moles of ethylene oxide trimethacrylate, and the end of the hydroxyl group of trimethylolpropane is added with an average of 15 moles of ethylene oxide. The methacrylate is added to the terminal of the hydroxyl group of trimethylolpropane to have an average of 30 moles of ethylene oxide trimethacrylate or the like.

In one embodiment, the photosensitive resin composition preferably contains a compound represented by the following formula (IV) as (C) a compound having an ethylenic double bond.

In the formula, n ₁ , n ₂ , n ₃ , and n ₄ each independently represent an integer of 1 to 25, and n ₁ + n ₂ + n ₃ + n ₄ is an integer of 4 to 100, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, and R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkylene group, and when a plurality of R ₅ , R ₆ , R ₇ and R ₈ are respectively present, The plurality of R ₅ , R ₆ , R ₇ , and R ₈ may be the same or different from each other}.

In the formula (IV), n ₁ + n ₂ + n ₃ + n _{4 is} preferably 9 or more and 60 or less. From the viewpoint of suppressing the generation of the resist crotch portion, the viewpoint of improving the puncture resistance of the cover film, and the flexibility imparted to the cured film, it is preferable to set n ₁ + n ₂ + n ₃ + n ₄ . On the other hand, on the other hand, from the viewpoint of improving the resolution and adhesion, obtaining good peeling characteristics, and controlling the edge meltability, it is preferable that n ₁ + n ₂ + n ₃ + n ₄ Set to 60 or less. Further, a more preferable range of n ₁ + n ₂ + n ₃ + n ₄ is 9 or more and 40 or less, and further preferably 15 or more and 40 or less, and particularly preferably 15 or more and 28 or less.

As R ₅ , R ₆ , R ₇ and R ₈ in the formula (IV), respectively, a 1,2-extended ethyl group, a 1,2-extended propyl group, a butyl group, etc. may be imparted to the cured film. From the viewpoint of flexibility, the viewpoint of improving the puncture resistance of the mask film, the viewpoint of suppressing development cohesiveness, and the viewpoint of improving the reactivity of the ethylenic double bond, a 1,2-extended ethyl group is preferred. Therefore, the compound represented by the formula (IV) is preferably a compound represented by the following formula (V).

[wherein, n ₁ , n ₂ , n ₃ , and n ₄ are each independently an integer of 1 to 25, wherein n ₁ + n ₂ + n ₃ + n ₄ is an integer of 4 to 100, R ₁ , R ₂ And R ₃ and R ₄ are each independently an alkyl group}. The preferred range of n ₁ + n ₂ + n ₃ + n ₄ is the same as described above.

Specific examples of the compound represented by the above formula (IV) include tetramethyl methacrylate having an average of 9 moles of ethylene oxide at the terminal end of the hydroxyl group of pentaerythritol, and terminal end of the hydroxyl group of pentaerythritol. Addition of tetramethacrylate with an average of 12 moles of ethylene oxide, tetramethyl methacrylate with an average of 15 moles of ethylene oxide at the end of the hydroxyl group of pentaerythritol, and terminal end of the hydroxyl group of pentaerythritol Addition of tetramethacrylate with an average of 20 moles of ethylene oxide, addition of tetramethyl methacrylate with an average of 28 moles of ethylene oxide at the end of the hydroxyl group of pentaerythritol, at the end of the hydroxyl group of pentaerythritol An average of 35 moles of ethylene oxide tetramethacrylate or the like is added.

In one embodiment, the photosensitive resin composition preferably contains a compound represented by the following formula (VI) as (C) a compound having an ethylenic double bond.

Wherein R ₃ and R ₄ are each independently a hydrogen atom or a methyl group; n ₉ and n ₁₁ are each independently an integer of 0 to 20, and n ₉ + n ₁₁ is an integer of 0 to 20; n ₈ and n ₁₀ Independently being an integer from 1 to 20, and n ₈ + n ₁₀ is an integer from 2 to 20; the arrangement of repeating units of -(C ₂ H ₄ O)- and -(C ₃ H ₆ O)- may be random It may also be a block, and any of -(C ₂ H ₄ O)- and -(C ₃ H ₆ O)- may be bonded to the bisphenol structure}.

In the formula (VI), it is preferred that n ₈ + n ₉ + n ₁₀ + n ₁₁ is 2 or more and 40 or less. From the viewpoint of obtaining the flexibility of the cured film, it is preferable to set n ₈ + n ₉ + n ₁₀ + n ₁₁ to 2 or more. On the other hand, from the viewpoint of obtaining resolution, it is preferred that n ₈ +n ₉ +n ₁₀ +n _{11 is} set to 40 or less. Further, in order to obtain chemical resistance, a more preferable range of n ₈ + n ₉ + n ₁₀ + n ₁₁ is 4 or more and 20 or less, and a more preferable range is 6 or more and 12 or less. Further, in order to obtain the hiding property, a more preferable range of n ₈ + n ₉ + n ₁₀ + n ₁₁ is 16 or more and 40 or less, and further preferably a range of 30 or more and 40 or less. Further preferably, n ₉ + n ₁₁ is an integer of 1 to 20, and n ₈ + n ₁₀ is an integer of 2 to 20.

Specific examples of the compound represented by the above formula (VI) include ethylene glycol dimethacrylate obtained by adding an average of 2 moles of ethylene oxide to both ends of bisphenol A. The ester is added to the two ends of bisphenol A to form an ethylene glycol dimethacrylate having an average of 5 moles of ethylene oxide, and an average of 6 moles is added to both ends of the bisphenol A. Dialkyl methacrylate of ethylene oxide with an average of 2 moles of propylene oxide, and an average of 15 moles of ethylene oxide and an average of bisphenol A 2 dimethyl propylene oxide of dialkyl propylene oxide and the like.

In one embodiment, the photosensitive resin composition may be a compound represented by each of the above formulas (III), (IV), and (VI) as (C) a compound having an ethylenic double bond, in addition to the above. Further, it may further contain other (C) compounds.

As the other (C) compound, an ethylenically unsaturated compound which can be photopolymerized can be used. As such a photopolymerizable ethylenically unsaturated compound, for example, it can be exemplified: A compound having one ethylenic double bond, a compound having two ethylenic double bonds, and a compound having three or more ethylenic double bonds.

Examples of the compound having one ethylenic double bond include a compound obtained by adding (meth)acrylic acid to one end of a polyalkylene oxide; and a methyl group at one end of the polyalkylene oxide. Acrylic acid, a compound obtained by etherifying or allyl etherizing the other terminal alkyl group, and the like.

Examples of the compound having two ethylenic double bonds in the molecule include a compound having a (meth)acryloyl group at both terminals of the alkylene oxide chain; and a random amount in the ethylene oxide unit and the propylene oxide unit. a compound having a (meth) acrylonitrile group at both ends of the alkylene oxide chain bonded by alternating, or blockwise; having (methyl) at both ends of the alkylene oxide-modified bisphenol A a compound of an acrylonitrile group or the like.

Among these, from the viewpoint of resolution and adhesion, a compound having a (meth)acryl fluorenyl group at both ends of the alkylene oxide-modified bisphenol A is preferred. Examples of the alkylene oxide modification include ethylene oxide modification, propylene oxide modification, butylene oxide modification, pentylene oxide modification, and hexylene oxide modification. More preferably, it is a compound having a (meth)acryl fluorenyl group at both ends of the ethylene oxide-modified bisphenol A.

A compound having three or more ethylenic double bonds in the molecule can be obtained, for example, by using a compound having a group of an alkylene group having an alkyl group of 3 mol or more in the molecule as a central skeleton, and adding the compound. An alkyloxy group such as an ethoxy group, a propoxy group, or a butoxy group is formed, and the obtained alcohol is made into a (meth) acrylate. In this case, examples of the compound which can be a central skeleton include glycerin, trimethylolpropane, pentaerythritol, dipentaerythritol, and a compound having an isocyanurate ring.

Specific examples of the compound having three or more ethylenic double bonds in the molecule include polypropylene glycol di(meth)acrylate, polyethylene glycol (meth)acrylate, and 2-two. (p-hydroxyphenyl)propane (meth) acrylate, tris (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyoxypropyl trimethylol propane tri (methyl) Acrylate, polyoxyethyltrimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, trimethylpropane triglycidyl ether Acrylate, phenoxy polyethylene glycol (meth) acrylate, nonyl phenoxy polyethylene glycol (meth) acrylate, and the like.

The other (C) compounds may be used singly or in combination of two or more.

When the mass of the solid content of the photosensitive resin composition is 100% by mass, the compounding amount of the compound having an ethylenic double bond in (C) in the photosensitive resin composition is 5 to 50% by mass. The blending amount is 5% by mass or more based on the viewpoint of improving the sensitivity, the resolving property, and the adhesion. On the other hand, the blending amount is 50% by mass or less based on the viewpoint of suppressing edge melting and suppressing the hardening resistance. The viewpoint of the peeling delay of the etchant. The blending amount is more preferably 25 to 45% by mass.

In the case where the compound having an ethylenic double bond (C) contains a compound represented by the above formula (III), the total amount of the solid component of the photosensitive resin composition is set to 100% by mass based on the compounding amount of the compound. In the case of 2% by mass or more and 40% by mass or less, more preferably 5% by mass or more and 30% by mass or less, and still more preferably 10% by mass or more and 20% by mass or less.

In the case where the compound having an ethylenic double bond (C) contains a compound represented by the above formula (IV), the compounding amount of the compound is set to 100% by mass based on the total solid content of the photosensitive resin composition. In the case of 2% by mass or more and 40% by mass or less, more preferably 5% by mass or more and 30% by mass or less, and still more preferably 10% by mass or more and 20% by mass or less.

In the case where the compound having an ethylenic double bond (C) contains a compound represented by the above formula (VI), the total amount of the solid component of the photosensitive resin composition is set to 100% by mass based on the compounding amount of the compound. In time, it is preferably 2% by mass or more and 40% by mass or less. The amount is preferably 5% by mass or more and 30% by mass or less, and more preferably 10% by mass or more and 20% by mass or less.

<leuco dye, fluorescent yellow mother dye, coloring matter>

The photosensitive resin composition of the present invention may contain one or more selected from the group consisting of a leuco dye, a fluorescent yellow mother dye, and a coloring material. The photosensitive resin composition is colored by the exposed portion by containing the components. Therefore, it is preferable from the viewpoint of visibility. Further, when the inspection machine or the like reads the alignment mark for exposure, it is advantageous in that the contrast between the exposure portion and the unexposed portion is increased and the recognition is easy.

Examples of the leuco dye include tris(4-dimethylaminophenyl)methane [leuco crystal violet], bis(4-dimethylaminophenyl)phenylmethane [hidden malachite green], and the like. . In particular, from the viewpoint of a good contrast, it is preferred to use leuco crystal violet as a leuco dye.

When the mass of the solid content of the photosensitive resin composition is 100% by mass, the content of the leuco dye in the photosensitive resin composition is preferably from 0.1 to 10% by mass. From the viewpoint of improving the contrast between the exposed portion and the unexposed portion, the content is preferably made 0.1% by mass or more. The content is more preferably 0.2% by mass or more, still more preferably 0.3% by mass or more. On the other hand, from the viewpoint of maintaining the storage stability of the photosensitive resin composition and suppressing the generation of aggregates during development, the content is preferably 10% by mass or less. The content is more preferably 5% by mass or less, still more preferably 1% by mass or less.

Examples of the coloring matter include magenta, phthalocyanine green, golden amine base, p-magenta, crystal violet, methyl orange, Nero blue 2B, Victoria blue, and malachite green (manufactured by Hodogaya Chemical Co., Ltd., Aizen ( Registered trademark) MALACHITE GREEN), Basic Blue 20, Diamond Green (manufactured by Hodogaya Chemical Co., Ltd., Aizen (registered trademark) DIAMOND GREEN GH).

When the mass of the solid content of the photosensitive resin composition is 100% by mass, the content of the coloring matter in the photosensitive resin composition is preferably 0.001% by mass to 1% by mass. From the viewpoint of improving workability, the content is preferably 0.001% by mass or more. On the other hand, from the viewpoint of maintaining storage stability, the content is preferably 1% by mass or less.

<halogen compound>

In the photosensitive resin composition of the present embodiment, a leuco dye is used in combination with the following halogen compound, which is preferable from the viewpoint of adhesion and contrast.

Examples of the halogen compound include bromopentane, bromoisopentane, 1,2-dibromo-2-methylpropane, 1,2-dibromoethane, diphenylbromomethane, benzyl bromide, and Methyl bromide, tribromomethylphenyl hydrazine, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, iodopentane, iodoisobutane, 1,1,1- Trichloro-2,2-bis(p-chlorophenyl)ethane, chlorinated three Compounds, etc. It is especially preferred to be tribromomethylphenyl hydrazine. When a halogen compound such as tribromomethylphenyl hydrazine is used in combination with an acridine compound, the effect is improved, the resolution is improved, the adhesion is improved, the sensitivity is improved, the contrast is improved, the puncture resistance of the mask is improved, and the inhibition is suppressed. It is preferable from the viewpoint of generation of a resist portion and improvement of etching resistance.

In view of the above, when the mass of the solid content of the photosensitive resin composition is 100% by mass, the content of the halogen compound in the photosensitive resin composition is preferably 0.01% by mass. The content is more preferably 0.1% by mass or more, further preferably 0.3% by mass or more, and particularly preferably 0.5% by mass or more. Moreover, it is preferable that the content is 3% by mass or less from the viewpoint of maintaining the storage stability of the hue in the photosensitive layer and suppressing the generation of aggregates during development. The content is more preferably 2% by mass or less, still more preferably 1.5% by mass or less.

<Radical polymerization inhibitors, benzotriazoles, carboxybenzotriazoles>

In the present embodiment, in order to improve the thermal stability and storage stability of the photosensitive resin composition, the photosensitive resin composition may further contain a radical polymerization inhibitor, a benzotriazole, and a carboxybenzotriene. At least one or more compounds selected from the group consisting of azoles.

Examples of the radical polymerization inhibitor include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, t-butyl catechol, biphenol, cuprous chloride, and 2,6. -two-number Tributyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6- Tributylphenol), 4,4'-thiobis(6-tert-butyl-m-cresol), 4,4'-butylenebis(3-methyl-6-tert-butylphenol), 1 , 1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, styrenated phenol (for example, manufactured by Kawaguchi Chemical Industry Co., Ltd., trade name "Antage SP"), Tribenzyl phenol (for example, manufactured by Kawaguchi Chemical Industry Co., Ltd., trade name "TBP", phenol compound having 1 to 3 benzyl groups), nitrosophenylhydroxylamine aluminum salt, diphenylnitrosamine, etc. .

Examples of the benzotriazoles include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, and bis(N-2-ethylhexyl)aminone. Methyl-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-tolyltriazole, bis(N-2-hydroxyethyl) Aminomethylene-1,2,3-benzotriazole and the like.

Examples of the carboxybenzotriazoles include 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, and N-(N,N-di 2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, N-(N,N -Di-2-ethylhexyl)aminovinylcarboxybenzotriazole and the like.

The total content of the radical polymerization inhibitor, the benzotriazole, and the carboxybenzotriazole is such that the mass of the solid content of the photosensitive resin composition is 100% by mass. The total amount is preferably 0.01 to 3% by mass, more preferably 0.05 to 1% by mass. In view of the storage stability of the photosensitive resin composition, the content is preferably 0.01% by mass or more, and it is preferable to maintain the sensitivity and suppress the discoloration of the dye. This content is made 3% by mass or less.

<Plasticizer>

The photosensitive resin composition of this embodiment may contain a plasticizer as needed. Examples of the plasticizer include polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether, and the like. a polyoxyethylene monoethyl ether, a polyoxypropylene monoethyl ether, a polyoxyethylene polyoxypropylene monoethyl ether or the like; Phthalates such as diethyl phthalate; o-toluenesulfonamide, p-toluenesulfonamide, tributyl citrate, triethyl citrate, triethyl citrate triacetate, acetamidine Tri-n-propyl citrate, tri-n-butyl citrate, etc.; propylene glycol with propylene oxide added to both ends of bisphenol A, and ethylene oxide added to both ends of bisphenol A Ethylene glycol and the like.

These may be used alone or in combination of two or more.

In particular, the viewpoint of improving the peeling characteristics, the deterioration of the resolution and the adhesion, the viewpoint of suppressing the occurrence of the resist crotch, the viewpoint of improving the flexibility of the cured film, and the improvement of the puncture resistance of the cover film. From the viewpoint of viewpoint, it is preferred to use p-toluenesulfonamide as a plasticizer.

The content of the plasticizer in the photosensitive resin composition is preferably from 1 to 50% by mass, more preferably from 1 to 30%, when the mass of the solid content of the photosensitive resin composition is 100% by mass. %. In view of suppressing the delay of the development time and imparting flexibility to the cured film, the content is preferably 1% by mass or more, and from the viewpoint of suppressing insufficient hardening and edge melting, it is preferably The content is made 50% by mass or less.

<solvent>

The photosensitive resin composition can be used by being dissolved in a solvent to prepare a solution. Examples of the solvent to be used include a ketone represented by methyl ethyl ketone (MEK, Methyl Ethyl Ketone), an alcohol represented by methanol, ethanol, and isopropyl alcohol.

The solvent is preferably added to the photosensitive resin composition such that the viscosity of the solution of the photosensitive resin composition applied to the support film is 500 to 4,000 mPa·s at 25° C.

<Characteristics of Photosensitive Resin Composition>

The photosensitive resin composition of the present embodiment is formed on the surface of the substrate to contain the photosensitive The photosensitive resin layer having a thickness of 25 μm in the resin composition is exposed by using a Stuffer 21-stage exposure meter as a mask, and then the highest residual film level at the time of development is 6 exposure amount to the photosensitive resin layer. When the exposure is performed, the average number of the ethylenic double bonds in the compound (C) is set to Q, and the reaction rate of the ethylenic double bond in the (C) compound after the exposure is set to P. In the case of the case, the value of P × Q / 100 is preferably 0.7 or more.

This is a necessary condition for sufficiently reacting the ethylenic double bond in the hardened resist pattern to achieve a sufficient crosslinking density and suppressing the generation of the resist crotch in the weakly exposed region. In order to suppress the generation of the resist crotch portion as much as possible, the value of P × Q / 100 is more preferably 1.0 or more, further preferably 1.5 or more, further preferably 1.7 or more, particularly preferably 2.0 or more, and most preferably 2.5. the above. On the other hand, in order to easily peel off the used resist pattern after the formation of the circuit pattern, the value of P × Q / 100 is more preferably 5.0 or less, further preferably 4.0 or less, and particularly preferably 3.5 or less.

From the same viewpoint as described above, a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition of the present embodiment is formed on the surface of the substrate, and exposure is performed by using a Stuart 21-stage exposure meter as a mask, followed by exposure. The exposure amount of the highest residual film level at the time of development is 1/10 of the exposure amount of the sixth stage. When the photosensitive resin layer is exposed, the average number of ethylenic double bonds in the compound (C) is set to Q, and the value of P' × Q / 100 in the case where the reaction rate of the ethylenic double bond in the compound (C) after the above exposure is P' is preferably 0.3 or more. The exposure amount at this time is a value considering the exposure amount of the weak exposure region. For the same point of view as above, the value of P'×Q/100 above

More preferably, it is 0.5 or more, further preferably 0.7 or more, further preferably 1.0 or more, further preferably 1.3 or more, particularly preferably 1.6 or more, most preferably 1.9 or more, more preferably 5.0 or less, still more preferably 3.0. Below, it is particularly preferably 2.5 or less.

When the transmittance at 405 nm (h-ray) when the polyethylene film of the photosensitive resin laminate is peeled off is less than 65%, the value of P×Q/100 is directly drawn by using the h-ray. The measurement was carried out under the exposure conditions of the exposure machine. When the transmittance at 405 nm (h-ray) when the polyethylene film of the photosensitive resin laminate is peeled off is 65% or more, the value of P×Q/100 is based on the exposure of the direct drawing exposure machine using i-rays. The measurement was carried out under the conditions.

The above value of P' x Q/100 is measured under the exposure conditions of an exposure machine using an ultrahigh pressure mercury lamp.

<Photosensitive Resin Laminate>

A photosensitive resin laminate can be formed using the photosensitive resin composition of the present invention. Typically, the photosensitive resin laminate has a support film and a photosensitive resin layer containing the photosensitive resin composition laminated on the support film. The photosensitive resin laminate may have a protective layer on the surface opposite to the support film side as needed.

As the support film, it is preferable to make the light emitted from the exposure light source transparent. Examples of such a support film include a polyethylene terephthalate film, a polyvinyl alcohol film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyvinylidene chloride film, a vinylidene chloride copolymer film, and A polymethyl methacrylate copolymer film, a polystyrene film, a polyacrylonitrile film, a styrene copolymer film, a polyamide film, a cellulose derivative film, or the like. These films may also be extended as needed.

It is preferred that the support film has a haze of 5 or less.

It is advantageous in that the thickness of the support film is thinner than image formation and economy, but it is preferably 10 to 30 μm if the function of maintaining strength is also considered.

An important characteristic of the protective layer used in the photosensitive resin laminate is that it has an appropriate adhesive force. In other words, it is preferable that the adhesion between the protective layer and the photosensitive resin layer is sufficiently smaller than the adhesion between the support film and the photosensitive resin layer, and the protective layer can be easily peeled off from the photosensitive resin laminate. As the protective layer, for example, a polyethylene film, a polypropylene film, a film excellent in peelability as disclosed in JP-A-59-202457, and the like can be used.

The film thickness of the protective layer is preferably from 10 to 100 μm, more preferably from 10 to 50 μm.

The thickness of the photosensitive resin layer in the photosensitive resin laminate is not depending on the use. The same, but preferably 5 to 100 μm, more preferably 7 to 60 μm. The thinner the thickness of the photosensitive resin layer, the higher the resolution, and the thicker the film strength is.

<Method for Producing Photosensitive Resin Laminate>

The photosensitive resin laminate can be produced by sequentially laminating a photosensitive resin layer on the support film and optionally a protective layer. As the method, a known method can be employed. For example, a photosensitive resin composition used in the photosensitive resin layer is mixed with a solvent which dissolves them to prepare a uniform coating solution. Then, the coating liquid can be applied onto the support film by a bar coater or a roll coater, followed by drying, and a photosensitive resin layer containing the photosensitive resin composition is laminated on the support film. Then, the protective layer is laminated on the photosensitive resin layer as needed, whereby a photosensitive resin laminate can be produced.

<Circuit pattern forming method>

According to another embodiment of the present invention, there is provided a method of forming a circuit pattern comprising the steps of forming a layer of the photosensitive resin composition of the present invention on a substrate (lamination step), and the photosensitive resin composition The step of exposing and developing to form a resist pattern (exposure step and development step), and the step of etching or plating the substrate on which the resist pattern is formed (etching step or plating step).

It is preferable to further include a peeling step of peeling the resist pattern from the laminated body after the series of steps described above.

In a preferred embodiment, the layer of the photosensitive resin composition is formed using the above-mentioned photosensitive resin laminate.

Hereinafter, an example of a method of forming a circuit pattern using a photosensitive resin laminate and a copper foil laminate as a substrate will be described.

(1) Lamination step

The protective layer of the photosensitive resin composition is peeled off and adhered to a substrate such as a copper foil laminate or a flexible substrate, for example, by a heat roll laminator.

(2) Exposure step

a step of exposing the layer of the photosensitive resin composition formed on the substrate to a mask film having a desired wiring pattern in a state in which the mask film is adhered to each other, by direct imaging exposure The step of exposing the desired wiring pattern or the exposing method by exposing the image of the photomask through the lens.

The advantages of the photosensitive resin composition of the present embodiment are more prominently exhibited by a direct imagewise exposure method using a direct drawing of a wiring pattern, or an exposure method of projecting an image of a reticle via a lens, and a direct imagewise exposure method Particularly prominently, it is preferred to employ a direct imaging exposure method in the exposure step.

(3) Development step

After the exposure step, after the support on the photosensitive resin layer is peeled off, the unexposed portion is developed and removed using a developing solution of an alkaline aqueous solution to form a resist pattern on the substrate.

As the alkaline aqueous solution, an aqueous solution of Na ₂ CO ₃ or K ₂ CO ₃ can be used. The alkaline aqueous solution is appropriately selected depending on the characteristics of the photosensitive resin layer, and is preferably a Na ₂ CO ₃ aqueous solution having a concentration of about 0.2 to 2% by mass and about 20 to 40 ° C.

A resist pattern can be obtained through the above steps. Optionally, after the steps, the heating step may be further carried out at about 100 ° C to 300 ° C for 1 minute to 5 hours. By performing this heating step, the adhesion or chemical resistance of the obtained hardened resist pattern can be further improved. In this case, for example, a heating furnace in the form of hot air, infrared rays, or far infrared rays may be used.

(4) etching step or plating step

By performing the surface of the substrate exposed by development (for example, the copper surface of the copper foil laminate) Etching or plating to produce a conductor pattern.

In the case of the etching step, the step of forming the desired circuit pattern by ejecting the etching solution from above by etching the etching solution formed on the resist pattern formed by the above steps to form a desired circuit pattern . Examples of the etching method include acid etching, alkaline etching, and the like, which are carried out by a method suitable for the photosensitive resin laminate used.

(5) Stripping step

Thereafter, the laminate is treated by an aqueous solution having a stronger alkalinity than the developer to peel the resist pattern from the substrate. The alkaline aqueous solution for peeling is not particularly limited. An aqueous solution of NaOH or KOH having a concentration of about 2 to 5% by mass and a temperature of about 40 to 70 ° C is generally used. A small amount of a water-soluble solvent may also be added to the stripping solution.

[Examples]

Hereinafter, the present invention will be more specifically described by way of examples and comparative examples.

First, the production methods of the samples for evaluation of the examples and the comparative examples will be described, and then the evaluation methods and evaluation results relating to the obtained samples will be described.

(1) Evaluation of alkali-soluble polymers <Measurement of Weight Average Molecular Weight>

The weight average molecular weight of the polymer was determined by a gel permeation chromatography (GPC, Gel Permeation Chromatography) manufactured by JASCO Corporation. The machine configuration and reagents used are as follows.

Pump: manufactured by Gulliver, PU-1580

Pipe column: manufactured by Showa Denko Co., Ltd., and connected four of Shodex (registered trademark) KF-807, KF-806M, KF-806M, and KF-802.5 in series.

Flow layer solvent: tetrahydrofuran

Calibration curve: Made using polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko Co., Ltd.)

(2) Method for producing sample for evaluation

The samples for evaluation in the examples and the comparative examples were produced in the following manner.

<Production of Photosensitive Resin Laminate>

The component shown in the first table below (wherein the number in each component column indicates the amount (parts by mass) based on the solid content) and the solvent are sufficiently mixed by stirring to prepare a photosensitive resin combination. Mixture. In the photosensitive resin composition preparation liquids of Examples 1 to 19 and Comparative Examples 1 to 8, 0.05 parts by mass of diamond green as a coloring matter and a component described in the first table were added as a leuco dye. 0.6 parts by mass of leuco crystal violet; 1-(2-di-n-butylaminomethyl)-5-carboxybenzotriazole and 1-(2-di-n-butylamine) as benzotriazoles 0.2 parts by mass of a 1:1 (mass ratio) mixture of methyl-)-6-carboxybenzotriazole; 0.05 parts by mass of hydrogenated bisphenol A diglycidyl ether as an antioxidant; as a radical polymerization inhibitor It is 0.004 parts by mass of an aluminum salt of 3 mol of nitrophenylhydroxylamine; and 2 parts by mass of p-toluenesulfonamide as a plasticizer.

Further, 0.7 parts by mass of tribromomethylphenylphosphonium as a halogen compound was added to the photosensitive resin composition preparation liquid other than Comparative Examples 1 and 2.

In the photosensitive resin composition preparation liquids of Examples 20 to 26, 28 to 44 and Comparative Examples a and 9 to 12, the above-mentioned additional components were not blended except as described in Table 1.

In addition, all of the photosensitive resin composition preparation liquid further contains a solvent which is added to the alkali-soluble polymer solution prepared in the preparation liquid, or a solvent added to adjust the concentration.

A 16 μm-thick polyethylene terephthalate film (manufactured by Teijin Dupont Films Co., Ltd., GR-16) was used as a support film, and a bar coater was used on the surface thereof to uniformly coat each of the above-prepared samples. The solution was adjusted and dried in a dryer at 95 ° C for 2.5 minutes to form a photosensitive resin composition layer. The dry thickness of the photosensitive resin composition layer was adjusted to 25 μm. Then, on the surface of the photosensitive resin composition layer (with polyterephthalic acid) On the surface opposite to the side of the ethylene glycol film, a 19 μm-thick polyethylene film (GF-18 manufactured by Tamapoly Co., Ltd.) was attached as a protective layer, whereby a photosensitive resin laminate was obtained.

In the second table below, the names of the components indicated by the abbreviations in Table 1 are disclosed.

<Substrate surface treatment>

A copper foil laminate having a thickness of 0.4 mm laminated with a rolled copper foil having a thickness of 35 μm was used as an evaluation substrate for imageability, resist crotch width, etching property, and peeling time. The substrate was treated with CPE-900 (registered trademark, manufactured by Lingjiang Chemical Co., Ltd.), and then surface-washed with 10% by mass of H ₂ SO ₄ , and further rinsed with pure water for use.

<Lamination>

The polyethylene film of the photosensitive resin laminate was peeled off and subjected to a surface treatment and preheated to a copper foil laminate having a temperature of 60 ° C, and was applied to a roll by a hot roll laminator (Al-700 manufactured by Asahi Kasei Co., Ltd.). Lamination was carried out at a temperature of 105 ° C, whereby a laminate for various evaluations was obtained. The air pressure system was set to 0.35 MPa, and the laminating speed was set to 1.5 m/min.

The evaluation other than the one described in the following evaluation methods was carried out using the laminated body after the lamination, and the sample produced under the conditions described in the items of various evaluation methods. The usual operation methods for exposure, development, etching, and peeling are described below.

<exposure>

In the exposure other than "(x)P'×Q/100" below, the direct drawing exposure machine (manufactured by Hitachi Via Mechanics Co., Ltd., DE-1DH, light source: GaN blue-violet diode (main wavelength 405±) 5 nm)), exposure was carried out under the conditions of an illuminance of 80 mW/cm ² using a Stutfel 21-stage exposure meter or a mask pattern for a specific DI exposure. This exposure is performed by exposing and developing the above-mentioned Stuffer 21-stage exposure meter as a mask to the exposure level of the sixth highest level of residual film.

For the substrate for evaluating items other than the width of the resist crotch, the position of the focus at the time of exposure is aligned with the surface of the substrate, With respect to the substrate for evaluating the width of the resist crotch portion, the position of the focus at the time of exposure was shifted from the substrate surface to the inside of the substrate by 200 μm in the thickness direction of the substrate.

<development>

After peeling off the polyethylene terephthalate film of the evaluation substrate which was exposed as described above, the temperature was adjusted to a temperature of 30 ° C using an alkaline developing machine (manufactured by Fujikiko, a developing machine for dry film). After the % Na ₂ CO ₃ aqueous solution was sprayed for a specific period of time, the pure water was sprayed for a predetermined period of time to be washed with water, and the unexposed portion of the photosensitive resin layer was dissolved and removed to prepare a hardened resist pattern.

The development time and the washing time were set to twice the minimum development time.

The minimum development time refers to the minimum time required to completely dissolve the photosensitive resin layer of the unexposed portion.

<etching>

The evaluation substrate which forms the hardened resist pattern by the above development is sprayed with a copper chloride etching apparatus (manufactured by Tokyo Chemical Machinery Co., Ltd., copper chloride etching apparatus) for a period of 1.3 times the minimum etching time. The copper chloride etching solution adjusted to 50 ° C was used to dissolve and remove the portion of the copper foil on the copper foil laminate which was not coated with the resist pattern.

The copper chloride etching solution was a solution in which the concentration of copper chloride was 250 g/L and the concentration of hydrochloric acid was 3 mol/L. The above-mentioned minimum etching time refers to the time required until the copper foil on the substrate is completely dissolved and removed.

<stripping>

The hardened resist pattern was peeled off by spraying an aqueous sodium hydroxide solution adjusted to a temperature of 50 ° C to 5% by mass of the substrate after the etching.

(3) Evaluation method of samples

Next, the evaluation method of the sample will be described.

(i) Sensitivity evaluation

For the evaluation of the substrate after 15 minutes of sensitivity after lamination, the Stuffer 21 exposure meter The mask is exposed. Then, development is performed twice as long as the minimum development time.

While changing the exposure amount, the above operation was repeated, and the exposure amount at which the maximum residual film level was 6 was investigated.

With respect to Examples 1 to 19 and Comparative Examples 1 to 8, the exposure amount in which the highest residual film level was six was classified by the following criteria.

○ (good): the case where the maximum residual film level becomes 6 levels and the exposure amount is less than 20 mJ/cm ²

× (defect): the case where the exposure amount of the highest residual film level is 6 or more is 20 mJ/cm ² or more

In Examples 20 to 26, 28 to 44, and Comparative Examples a and 9 to 12, the value of the exposure amount in which the highest residual film number was six was described in Table 1. In the application assumed in the examples, when the exposure amount is 70 mJ or less, the sensitivity is good, and it is preferably 40 mJ or less, more preferably 30 mJ or less, and still more preferably 20 mJ or less.

(ii) Resolution evaluation (1)

The substrate for evaluation which was passed for 15 minutes after lamination was exposed to a pattern of lines and spaces which became a ratio of the width of the exposed portion to the unexposed portion of 1:1. Then, development is performed at twice the development time of the minimum development time to obtain a hardened resist pattern. It was investigated that the minimum mask line width of the line and gap pattern in the hardened resist pattern was normally formed.

With respect to Examples 1 to 19 and Comparative Examples 1 to 8, the value of the minimum mask line width was graded by the following criteria.

○ (good): the case where the minimum mask line width is 25 μm or less

△ (may): the case where the minimum mask line width exceeds 25 μm and is 30 μm or less.

× (bad): the case where the minimum mask line width exceeds 30 μm

With respect to Examples 20 to 26, 28 to 44, and Comparative Examples a and 9 to 12, the value of the minimum mask line width is described in the first table. In the application assumed in the examples, when the minimum mask line width is 60 μm or less, the resolution (1) is good, preferably 35 μm or less, more preferably 25 μm or less, and still more preferably 20 μm. Hereinafter, it is preferably 16 μm or less.

(iii) Resolution evaluation (2)

Regarding some of the examples and comparative examples, in addition to the resolution evaluation (1) of the above (ii), the resolution evaluation of the positive independent release was also performed.

In other words, the substrate for evaluation which was passed for 15 minutes after lamination was exposed to a pattern in which the unexposed portion was a gap. Then, development is performed at a development time twice the minimum development time to obtain a hardened resist pattern. At this time, the value of the minimum gap width in which the gap of the unexposed portion is normally formed is set to the value of the resolution (positive independent mold release).

When the minimum gap width is 45 μm or less, the resolution (2) is preferably good, preferably 35 μm or less, more preferably 30 μm or less, further preferably 25 μm or less, and particularly preferably 20 μm or less.

(iv) Adhesion evaluation

The substrate for evaluation which was passed for 15 minutes after lamination was exposed to a pattern of the exposed portion. Then, development is performed at a development time twice the minimum development time to obtain a hardened resist pattern. The minimum mask line width at which the hardened resist line was normally formed was investigated.

With respect to Examples 1 to 19 and Comparative Examples 1 to 8, the minimum mask line width was classified by the following criteria.

○ (good): the case where the minimum mask line width is 25 μm or less

△ (may): the case where the minimum mask line width exceeds 25 μm and is 30 μm or less.

× (bad): the case where the minimum mask line width exceeds 30 μm

With respect to Examples 20 to 26, 28 to 44, and Comparative Examples a and 9 to 12, the value of the minimum mask line width is described in the first table. In the application assumed in the examples, when the minimum mask line width is 70 μm or less, the adhesion is good, preferably 30 μm or less, more preferably 25 μm or less, still more preferably 20 μm or less. More preferably, it is 10 μm or less.

(v) Evaluation of resist width

The substrate for evaluation which was passed for 15 minutes after lamination was exposed to a pattern of lines and gaps in which the width of the exposed portion and the unexposed portion was 1:1. At the time of exposure, the position of the focus at the time of exposure was shifted from the substrate surface by 200 μm toward the inside of the substrate in the thickness direction of the substrate. By In this measure, the weak exposure area of the exposure pattern end is enlarged, and the size comparison of the resist crotch width is easy.

After the exposed substrate was developed with a development time of twice the development time, the exposed portion of the copper substrate of the substrate was subjected to soft etching for 60 seconds by using a 200 g/L aqueous ammonium persulfate solution to obtain an evaluation resistance. A sample of the width of the etchant crotch. A line pattern portion of a ratio of 1:1 of L/S=45 μm/45 μm of the sample was observed by a scanning electron microscope <Hitachi High-Technologies, S-3400 N), and the pattern of the line pattern was determined. The width of the bottom portion.

With respect to Examples 1 to 19 and Comparative Examples 1 to 8, this value was defined as the resist line width, and the level was classified by the following basis:

◎ (very good): the case where the width of the resist crotch is 1.5 μm or less

○ (good): the case where the width of the resist crotch exceeds 1.5 μm and is 2.5 μm or less.

△ (may): the case where the width of the resist crotch is more than 2.5 μm and 3.5 μm or less

× (bad): the case where the width of the resist crotch exceeds 3.5 μm

With respect to Examples 20 to 26, 28 to 44, and Comparative Examples a and 9 to 12, the value of the width of the resist crotch portion is described in Table 1. In the application assumed in the examples, when the value of the width of the resist crotch portion is 10 μm or less, the adhesion is good, and preferably 3 μm or less, more preferably 2.5 μm or less, further preferably It is 2 μm or less, more preferably 1.5 μm or less, and particularly preferably 1 μm or less.

Refer to Fig. 1 for the method of measuring the width of the resist crotch portion.

(vi) Etchability evaluation

The substrate for evaluation which was passed for 15 minutes after lamination was exposed to a pattern of lines and gaps in which the width of the exposed portion and the unexposed portion was 1:1. This was developed by developing time twice as long as the development time, and after etching for 1.3 times of the minimum etching time, the hardened resist pattern was peeled off with an aqueous sodium hydroxide solution, thereby obtaining a conductor pattern. The conductor pattern was observed by an optical microscope (manufactured by Nikon, MM-800), and the conductor pattern was investigated. Shape and grade by reference to:

○ (good): a conductor pattern was formed linearly, and no fluctuations and penetration of the etching liquid were observed.

△ (may): a conductor pattern is formed linearly, but the penetration of the etching solution is slightly visible.

× (bad): a case where at least one of the case where the conductor pattern is not linearly formed and a case where the penetration of the etching liquid is clearly observed is observed

(vii) developer foamability evaluation

The photosensitive resin laminate produced in the above <Production of Photosensitive Resin Laminate> was cut into an area of 0.048 m ² , and the photosensitive resin layer from which the protective layer and the support film were peeled off was immersed in 120 ml of 1% by mass Na _{2 .} In a CO ₃ aqueous solution, a solution in which a resin layer was dissolved was obtained. This solution was added to a gas absorption tank having a capacity of 500 ml, and nitrogen gas of 6000 ml/min passed through a glass filter of G3 was passed. The time until the bubble generated from the gas absorption tank overflowed was measured, and the result was ranked by the following basis.

◎ (very good): no overflow in 100 seconds

○ (good): In case of overflow for more than 30 seconds and less than 100 seconds

× (bad): overflow within 30 seconds

(viii) Pressurized flow test

The photosensitive resin laminate produced in the above-mentioned <Production of Photosensitive Resin Laminate> was cut into 2.5 cm square, and the protective layer was peeled off, and then sandwiched in the center of 10 cm square of the polyethylene terephthalate film. A force of 100 kg was applied for 5 minutes from an oil hydraulic press heated to 40 °C. Then, the overflow width of the photosensitive resin layer was measured in the four directions (8 o'clock), and the average value was calculated|required. This test was carried out with n=2, and the average value of n=2 was calculated, and this average value was made into the value of the pressurized flow test.

It is known from experience that if the value is large, edge melting tends to occur, and it is substantially impossible to stably laminate the substrate on the substrate during lamination.

(ix) P×Q/100

The transmittance at 405 nm (h-ray) when the polyethylene film of the photosensitive resin laminate was peeled off was less than 65% in all of the examples and the comparative examples. Therefore, the value of P × Q / 100 is measured under exposure conditions using a direct drawing exposure machine using h rays.

From the side of the polyethylene terephthalate film (support layer) of the photosensitive resin laminate produced in the above-mentioned <Preparation of photosensitive resin laminated body>, a direct drawing exposure machine (manufactured by Hitachi Via Mechanics Co., Ltd., DE-1DH, light source: GaN blue-violet diode (main wavelength 405±5 nm), for direct imaging exposure. At this time, the position of the focus at the time of exposure is aligned with the bottom of the resist. The illuminance at the time of exposure was set to 80 mW/cm ² . The exposure amount at this time is exposed by using the Stuffer 21-stage exposure meter as a mask, and then the exposure amount of the highest residual film level at the time of development is 6 (normal exposure).

The reaction rate P of the ethylenic double bond of the hardened resist obtained by the above operation was determined by FT-IR (Fourier Transform Infrared Radiation) (manufactured by Thermo SCIENTIFIC, NICOLET 380). The peak height at a wave number of 810 cm ^-1 was measured, and this value was defined as the amount of the ethylenic double bond.

The average number (functional group number) of the ethylenic double bonds in the above (C) compound was calculated, and this value was made into Q. When the compound (C) is a mixture of a plurality of compounds, Q is determined in consideration of the content of each component.

Based on P and Q above, the value of P × Q / 100 is obtained.

(x)P'×Q/100

From the side of the polyethylene terephthalate film (support layer) of the photosensitive resin laminate produced in the above-mentioned <Preparation of photosensitive resin laminated body>, an ultrahigh pressure mercury lamp (HMW-801, manufactured by Oak Manufacturing Co., Ltd.) was used. Exposure. The exposure amount is performed by an exposure amount of 1/10 of the exposure amount in the above <(ix)P×Q/100> (rounding up to a decimal point). Except for the above, the reaction rate P' of the ethylenic double bond of the hardened resist in 1/10 exposure (weak exposure) was determined by FT-IR in the same manner as above.

Based on the value of P' and the value of Q calculated by the same method as described above, the value of P'xQ/100 at the time of weak exposure was obtained.

(xi) Hue stability of the photosensitive resin composition blending solution

The transmittance at 630 nm of the photosensitive resin laminate was measured by the following method using an ultraviolet-visible (UV-Vis) measuring device (manufactured by Hitachi High-Technologies Co., Ltd., U-3010 spectrophotometer):

(i) The polyethylene film of the photosensitive resin laminate was peeled off, and the transmittance at 630 nm was measured, and the obtained value was defined as the initial transmittance (T _in ).

(ii) A photosensitive resin laminate is prepared by using a photosensitive resin composition preparation liquid which has been stored at 40 ° C for 3 days, and the polyethylene film of the photosensitive resin laminate is peeled off to measure the transmittance at 630 nm. The value is set to the transmittance after storage (T _af ).

The hue stability is determined by the following formula: T _af -T _in .

(xii) stripping time

A rectangular pattern of 5 cm × 6 cm was exposed to the substrate for evaluation which was passed for 15 minutes after lamination. Then, development is performed at a development time twice the minimum development time to obtain a hardened resist pattern.

The hardened resist pattern on the substrate obtained by this operation was immersed in a 2% by mass aqueous NaOH solution at 50° C., and the time until the resist was completely peeled off from the substrate was measured, and this was set as the peeling time.

(xiii) hardened film softness

The photosensitive resin laminate was laminated on NIKAFLEX F-30VC1 25C1 1/2 (manufactured by NIKKAN INDUSTRIES), and a pattern having a width of 2.5 cm and a length of 30 cm was exposed. Then, development was performed at a development time twice the minimum development time, and a short strip sample was prepared.

So that the substrate side and the diameter are 1, 2, 3, 4, 5, and 6 mm The SUS rods are erected by means of contact. Then, both ends of the short strip sample were grasped so that the bending angle became 90 degrees, and the short strip sample was rubbed back and forth 10 times.

At this time, the diameter of the SUS rod having the largest crack was not formed on the resist surface, and the grade was classified as follows.

○ (good): at 4mm No cracks formed

△ (can): if it is 4mm Then cracks are formed, but if it is 5mm No cracks are formed

(xiiv) cover film puncture ductility

The photosensitive resin laminate was laminated on both surfaces of a substrate including a 1.6 mm-thick copper foil laminate having an opening of 6 mm in diameter, and the entire surfaces of both surfaces were exposed. Then, the hardened resist pattern was obtained by performing development with a development time twice as long as the minimum development time.

Then, using a column having a diameter of 1.5 mm, the puncturing strength and ductility of the film of the portion of the opening of the substrate were measured by Tensilon (RTM-500, manufactured by Orientec Co., Ltd.).

(3) Evaluation results

The evaluation results of the examples and comparative examples are shown in the first table.

Table 2 discloses the names of the components indicated by the abbreviations in Table 1. The alkali-soluble polymer shown in the second table was prepared by adding a methyl ethyl ketone solution having a solid content concentration as described in the above table. The abbreviation of the functional group type column of the compound having an ethylenic double bond in the second table has the following meanings.

A: acrylate group

MA: methacrylate group

The third table is a glass transition temperature (literature value) in the case where each of the monomers used in the synthesis of the alkali-soluble resin is a homopolymer.

[Industrial availability]

The photosensitive resin composition of the present embodiment, and the photosensitive resin laminate, the resist pattern, and the circuit pattern produced by using the same can be suitably used for the production of a printed wiring board, a flexible printed wiring board, and a lead for IC chip mounting. Manufacturing of frame, metal mask, semiconductor package such as BGA or CSP, tape substrate such as TAB or COF, semiconductor bump, ITO electrode, address electrode, electromagnetic wave mask, etc.

Claims (26)

A photosensitive resin composition containing (A) an alkali-soluble polymer: 40 to 80% by mass, (B) when the total mass of the solid content of the photosensitive resin composition is 100% by mass Photopolymerization initiator: 0.1 to 20% by mass, and (C) a compound having an ethylenic double bond: 5 to 50% by mass, and a photosensitive layer containing the photosensitive resin composition having a thickness of 25 μm is formed on the surface of the substrate. In the resin layer, the resist portion width of the resist pattern obtained by exposing and developing the position of the focus at the time of exposure from the substrate surface to the substrate inner side by 200 μm in the thickness direction is 0.01 From μm to 3.5 μm, and for direct imagewise exposure, the weight average Tg ^total of the Tg of the above (A) alkali-soluble polymer is 30 ° C or more and 125 ° C or less. The photosensitive resin composition of claim 1, wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to expose the Stutfe 21-level exposure meter as a mask, followed by exposure When the photosensitive resin layer is exposed to the highest residual film level at the time of development, the average number of ethylenic double bonds in the compound (C) is set to Q, and the exposure is performed. When the reaction rate of the ethylenic double bond in the above (C) compound is P, the value of P × Q / 100 is 0.7 or more. The photosensitive resin composition of claim 1 or 2, wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to expose the Stuttgart 21-level exposure meter as a mask. Then, the exposure amount of the highest residual film level at the time of development is 1/10 of the exposure amount of 6 stages, and the photosensitive resin layer is exposed. In the case where the average number of the ethylenic double bonds in the above (C) compound is Q, and the reaction rate of the ethylenic double bond in the above (C) compound after the above exposure is taken as P' The value of P'×Q/100 is 0.3 or more. The photosensitive resin composition of claim 1 or 2, wherein the compound (C) contains a compound having three or more methacryl groups in one molecule. The photosensitive resin composition of claim 1 or 2, wherein the compound (C) contains a compound having four or more methacryl groups in one molecule. The photosensitive resin composition of claim 1 or 2, wherein the compound (C) comprises a compound represented by the following formula (IV), In the formula, n ₁ , n ₂ , n ₃ , and n ₄ each independently represent an integer of 1 to 25, and n ₁ + n ₂ + n ₃ + n ₄ is an integer of 9 to 60, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, and R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkylene group, and when a plurality of R ₅ , R ₆ , R ₇ and R ₈ are respectively present, The plurality of R ₅ , R ₆ , R ₇ , and R ₈ may be the same or different from each other}. The photosensitive resin composition of claim 6, wherein in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of from 15 to 40. The photosensitive resin composition of claim 6, wherein in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of from 15 to 28. The photosensitive resin composition of claim 1 or 2, wherein the (B) photopolymerization initiator comprises an acridine compound. The photosensitive resin composition of claim 1 or 2, which further contains a halogen compound. The photosensitive resin composition of claim 1 or 2, wherein the (B) photopolymerization initiator comprises N-phenylglycine or a derivative thereof. The photosensitive resin composition of claim 1 or 2, wherein the (A) alkali-soluble polymer has an aromatic hydrocarbon group. A photosensitive resin composition containing (A) an alkali-soluble polymer: 40 to 80% by mass, (B) when the total mass of the solid content of the photosensitive resin composition is 100% by mass Photopolymerization initiator: 0.1 to 20% by mass, and (C) a compound having an ethylenic double bond: 5 to 50% by mass, and the above compound (C) contains 3 or more methacryl groups in one molecule The weight average Tg ^total of the Tg of the above (A) alkali-soluble polymer is 30 ° C or more and 125 ° C or less. The photosensitive resin composition of claim 13, wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to expose the Stutfe 21-level exposure meter as a mask, followed by exposure When the photosensitive resin layer is exposed to the highest residual film level at the time of development, the average number of ethylenic double bonds in the compound (C) is set to Q, and the exposure is performed. When the reaction rate of the ethylenic double bond in the above (C) compound is P, the value of P × Q / 100 is 0.7 or more. The photosensitive resin composition of claim 13 or 14, wherein a photosensitive resin layer having a thickness of 25 μm including the photosensitive resin composition is formed on the surface of the substrate to expose the Stuttgart 21-level exposure meter as a mask. Then, when the photosensitive resin layer is exposed to the highest residual film level at the time of development, the average number of ethylenic double bonds in the compound (C) is exposed. When Q is set and the reaction rate of the ethylenic double bond in the (C) compound after the above exposure is P', the value of P'xQ/100 is 0.3 or more. The photosensitive resin composition of claim 13 or 14, wherein the compound (C) contains a compound having 4 or more methacryl groups in one molecule. The photosensitive resin composition of claim 13 or 14, wherein the compound (C) comprises a compound represented by the following formula (IV), In the formula, n ₁ , n ₂ , n ₃ , and n ₄ each independently represent an integer of 1 to 25, and n ₁ + n ₂ + n ₃ + n ₄ is an integer of 9 to 60, R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, and R ₅ , R ₆ , R ₇ and R ₈ each independently represent an alkylene group, and when a plurality of R ₅ , R ₆ , R ₇ and R ₈ are respectively present, The plurality of R ₅ , R ₆ , R ₇ , and R ₈ may be the same or different from each other}. The photosensitive resin composition of claim 17, wherein in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of from 15 to 40. The photosensitive resin composition of claim 17, wherein in the above formula (IV), n ₁ + n ₂ + n ₃ + n ₄ is an integer of from 15 to 28. The photosensitive resin composition of claim 13 or 14, wherein the (B) photopolymerization initiator comprises an acridine compound. The photosensitive resin composition of claim 13 or 14, which further contains a halogen compound. The photosensitive resin composition of claim 13 or 14, wherein the (B) photopolymerization initiator comprises N-phenylglycine or a derivative thereof. The photosensitive resin composition of claim 13 or 14, wherein the (A) alkali-soluble polymer has an aromatic hydrocarbon group. The photosensitive resin composition of claim 13 or 14, which is used for direct imagewise exposure. A method of forming a circuit pattern, comprising the steps of: forming a layer of the photosensitive resin composition according to any one of claims 1 to 24 on a substrate; and exposing the layer of the photosensitive resin composition And developing a step of forming a resist pattern; and etching or plating the substrate on which the resist pattern is formed. The method of claim 25, wherein the exposing is performed by direct imaging exposure.