TWI480683B - A photosensitive resin composition and a photosensitive member using the same, a method for forming a photoresist pattern, and a method for manufacturing a printed circuit board - Google Patents

Description

Photosensitive resin composition, photosensitive element using the same, method for forming photoresist pattern, and method for manufacturing printed circuit board

The present invention relates to a photosensitive resin composition, a photosensitive element using the composition, a method for forming a photoresist pattern, and a method for producing a printed circuit board.

In the field of manufacturing a printed circuit board, a photosensitive resin composition or a photosensitive element (laminate) is widely used as a photoresist material for etching or plating.

The printed circuit board is manufactured as follows. First, a photosensitive resin composition layer of a photosensitive element is laminated on a circuit-forming substrate. Next, a predetermined portion of the photosensitive resin composition layer is irradiated with active light rays to expose and harden the predetermined portion. Then, after the support film is peeled off and removed, a portion other than the predetermined portion (unexposed or unhardened portion) is removed (developed) from the substrate, and a cured product of the photosensitive resin composition is formed on the substrate. Photoresist pattern. The obtained photoresist pattern is subjected to an etching treatment or a plating treatment to form a circuit on the substrate, and finally, the photoresist is removed and removed to produce a printed circuit board.

Here, the etching treatment refers to a method of etching away the conductive layer of the circuit-forming substrate which is not covered by the photoresist pattern, and then peeling off the photoresist. In addition, the plating treatment is performed by performing a plating treatment of copper, solder, or the like on a conductive layer of a circuit-forming substrate that is not covered by a photoresist pattern, and then removing the photoresist and soft-etching the metal surface covered by the photoresist. Methods.

In the above exposure method, a method in which a mercury lamp is used as a light source and exposure is performed via a photomask is conventionally used. In addition, in recent years, a direct drawing exposure method in which a digital data of a pattern called DLP (Digital Light Processing) or LDI (Laser Direct Imaging) is directly drawn on a photosensitive resin composition layer has been proposed (see Non-Patent Document 1). The direct drawing exposure method is more accurate in positional alignment than the exposure method via the photomask, and a high-definition pattern can be obtained, and is introduced into a high-density package substrate.

However, the above-described direct drawing exposure method light source uses monochromatic light such as laser light to scan the substrate and simultaneously irradiate light. Therefore, compared with the conventional exposure method, there is a tendency for a long exposure time. Therefore, in order to shorten the exposure time and increase the production efficiency, it is necessary to increase the sensitivity of the photosensitive resin composition.

In addition, with the increase in density of printed circuit boards in recent years, it is further required to form a resolution pattern (removal accuracy of an unexposed portion) and a photoresist pattern having higher adhesion to a substrate (resistance liquid resistance of an exposed portion). A photosensitive resin composition. In particular, in the production of a package substrate, it is required to form a photosensitive resin composition having a resist pattern of a line width/pitch width (L/S) of 10/10 (unit: μm) or less.

Since the high-density package substrate has a narrow width between circuits, an excellent photoresist shape (a cross-sectional shape of a photoresist pattern) is also important. When the cross-sectional shape of the photoresist is trapezoidal or inverted trapezoidal, or the photoresist has a bottom edge folded, the circuit formed by the subsequent etching treatment or plating treatment may cause a short circuit or a broken wire, which is not preferable, and the photoresist shape is not good. It is a rectangle, and the bottomless edge is preferably folded.

The photosensitive resin composition is excellent in peeling properties after hardening (easiness in peeling off the cured product from the substrate). In other words, by means of photoresist The peeling time is shortened, and the production efficiency of the peeling step is improved. Further, by reducing the size of the peeling sheet of the photoresist, the peeling sheet is prevented from adhering to the circuit board again, and the production yield is improved.

Patent Document 1 discloses a photosensitive resin composition having a good sensitivity for directly drawing an exposure method, and is a photosensitive resin composition using a specific binder polymer or a sensitizing dye.

Patent Document 2 discloses a photosensitive resin composition in which a polyfunctional acrylate compound is introduced to increase the adhesion to a substrate, and a crosslinking point is increased.

Patent Document 3 discloses that a photosensitive resin composition of a polymerization inhibitor such as catechol or hydroquinone is used in order to improve the contrast (developability) between the exposed portion and the unexposed portion.

[Previous Technical Literature] [Patent Document]

Patent Document 1: JP-A-2005-122123

Patent Document 2: JP-A-2003-215799

Patent Document 3: JP-A-2000-162767

[Non-patent literature]

[Non-Patent Document 1] "Electronic Mounting Technology", June 2002 issue, p.74-79

[Summary of the Invention]

The photosensitive resin composition is required to improve various characteristics such as sensitivity, resolution, adhesion, photoresist shape, and peeling property after curing in a well-balanced manner.

However, the photosensitive resin composition described in Patent Document 1 has good sensitivity and peeling properties, but the resolution and the adhesion are not necessarily sufficient.

The photosensitive resin composition described in Patent Document 2 has good adhesion, but the peeling property is insufficient, and the cured product tends to be difficult to be peeled off from the substrate.

The photosensitive resin composition described in the patent document 3 is excellent in resolution, adhesion, and developability, but the sensitivity is insufficient, and when the direct drawing exposure method is used, a large exposure time is required.

As described above, the conventional photosensitive resin compositions are not well balanced and sufficiently satisfy various characteristics required for the photosensitive resin composition for forming a photoresist pattern.

Accordingly, an object of the present invention is to provide a photosensitive resin composition excellent in sensitivity, resolution, adhesion, photoresist shape, and peeling property after hardening, and a photosensitive element and a photoresist pattern using the composition. A method of forming the same and a method of manufacturing a printed circuit board.

In order to achieve the above object, the present invention provides a photosensitive resin composition containing a photosensitive resin composition of (A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator. Wherein (A) the binder polymer has a structural unit based on (meth)acrylic acid, and a knot based on benzyl (meth)acrylate or benzyl (meth)acrylate derivative The unit (B) photopolymerizable compound contains the compound represented by the following general formula (1).

In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a methyl group, and a, b and c each independently represent an integer of 1 to 48, and the total number of a, b and c is 6 to 50. .

In other words, since the photosensitive resin composition of the present invention has the above-described configuration, the sensitivity, the resolution, the adhesion, the resist shape, and the peeling property after curing are all good. The inventors of the present invention thought that by using a (A) binder polymer having a specific structural unit, the resolution and the peeling property after hardening can be improved, and (B) photopolymerizability by using the compound represented by the above general formula can be used. The compound can improve the resolution, the adhesion, and the shape of the photoresist, and in combination, a photosensitive resin composition satisfying all of the above characteristics can be obtained. Further, in combination of the (A) binder polymer and the (B) photopolymerizable compound and the (C) photopolymerization initiator, good sensitivity can be obtained.

In the photosensitive resin composition of the present invention, the (B) photopolymerizable compound may further contain a bisphenol A-based (meth) acrylate compound. Thereby, the alkali developability, resolution, and hardness of the photosensitive resin composition can be further improved. Peeling characteristics after the transformation.

Further, the (B) photopolymerizable compound may further contain a compound having one ethylenically unsaturated bond. Thereby, the alkali developability, the resist shape, and the peeling property after hardening of the photosensitive resin composition can be further improved.

(B) The photopolymerizable compound may further contain a polyalkylene glycol di(meth)acrylate compound having a (poly)oxyethylene chain and a (poly)oxypropylene chain. Thereby, the flexibility of the cured product (cured film) of the photosensitive resin composition can be further improved.

In the photosensitive resin composition of the present invention, the (C) photopolymerization initiator may contain a 2,4,5-triarylimidazole dimer. Thereby, the sensitivity and adhesion of the photosensitive resin composition can be further improved.

The photosensitive resin composition of the present invention may further contain (D) a sensitizing dye from the viewpoint of further improving the sensitivity of the photosensitive resin composition.

The photosensitive resin composition of the present invention may further contain (E) an amine compound from the viewpoint of further improving the sensitivity of the photosensitive resin composition.

In the photosensitive resin composition of the present invention, the (A) binder polymer may contain a structural unit based on styrene or a styrene derivative. Thereby, the resolution and adhesion of the photosensitive resin composition can be further improved.

Further, the (A) binder polymer may further contain a structural unit based on an alkyl (meth)acrylate. Thereby, alkali developability and peeling characteristics can be further improved.

(A) The weight average molecular weight of the binder polymer is preferably from 10,000 to 100,000. Thereby, the photosensitive resin composition can be more balanced and improved. The alkali resolution of the substance, the development time, and the liquid resistance (adhesion).

The acid value of the (A) binder polymer is preferably from 100 to 250 mgKOH/g from the viewpoint of alkali resolution and adhesion (resistance to liquid).

Further, the present invention provides a photosensitive element comprising a support film and a photosensitive resin composition layer composed of the photosensitive resin composition formed on the support film. By using the photosensitive element of the present invention, a photoresist pattern having excellent resolution, adhesion, photoresist shape, and peeling property after curing can be formed with good sensitivity and efficiency.

Furthermore, the present invention provides a method for forming a photoresist pattern, comprising: a lamination step of laminating a photosensitive resin composition layer composed of the photosensitive resin composition on a substrate; and a photosensitive resin composition An exposure step of irradiating the active light with a predetermined portion of the layer to expose and harden the predetermined portion; and removing a portion other than the predetermined portion of the photosensitive resin composition layer from the substrate to form a photosensitive resin on the substrate A step of developing a photoresist pattern formed by a cured product of the composition. Thereby, a photoresist pattern having excellent resolution, adhesion, photoresist shape, and peeling property after hardening can be formed with good sensitivity and efficiency.

The wavelength of the above active light is preferably from 390 to 420 nm. Thereby, a photoresist pattern having good resolution, adhesion, and photoresist shape can be formed with good sensitivity and efficiency.

Further, the present invention provides a method of manufacturing a printed circuit board comprising the step of etching or plating a substrate on which a photoresist pattern is formed by the above-described photoresist pattern forming method. According to this manufacturing method, it is possible to accurately and efficiently manufacture a package such as a high-density package substrate and a wafer. A printed circuit board with high-density wiring.

According to the present invention, a photosensitive resin composition excellent in sensitivity, resolution, adhesion, photoresist shape, and peeling property after hardening can be provided, and a photosensitive element or a resist pattern using the composition can be provided. A method of forming and a method of manufacturing a printed circuit board.

[Formation of the Invention]

The best mode for carrying out the invention will be described in detail below. However, the present invention is not limited to the following embodiments. Further, in the present specification, (meth)acrylic means acryl or methacrylic acid, (meth) acrylate means acrylate or methacrylate, and (meth) acryl oxime means propylene fluorenyl or Acryl fluorenyl. Further, the (poly)oxyethylene chain means an oxyethylene group or a polyoxyethylene chain, and the (poly)oxypropylene chain means an oxypropylene group or a polyoxypropylene chain.

<Photosensitive resin composition>

The photosensitive resin composition of the present invention contains (A) a binder polymer (hereinafter also referred to as "(A) component)", (B) a photopolymerizable compound (hereinafter also referred to as "(B) component)"), and (C) Photopolymerization initiator (hereinafter also referred to as "(C) component").

Hereinafter, each of the photosensitive resin compositions constituting the present invention will be described in more detail. ingredient.

[(A) component: binder polymer]

The binder polymer of the component (A) has a structural unit based on (meth)acrylic acid and a structural unit based on benzyl (meth)acrylate or benzyl (meth)acrylate derivative. Such a binder polymer can be obtained, for example, by radical polymerization of (meth)acrylic acid with benzyl (meth)acrylate or a benzyl (meth)acrylate derivative. If necessary, it can be copolymerized with other polymerizable monomers.

The benzyl (meth) acrylate derivative is, for example, a benzyl group of benzyl (meth) acrylate and/or a phenyl group.

The content of the structural unit based on the benzyl (meth) acrylate or the benzyl (meth) acrylate derivative in the component (A) is relative to the component (A) from the viewpoint of the resolving property and the peeling property after curing. The mass is 100 parts by mass, preferably 5 to 65 parts by mass, more preferably 10 to 55 parts by mass, still more preferably 20 to 45 parts by mass. The content of the above structural unit is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 20 parts by mass or more from the viewpoint of further improving the resolution. The content of the above structural unit is preferably 65 parts by mass or less, more preferably 55 parts by mass or less, and still more preferably 45 parts by mass or less from the viewpoint of further improving the peeling property after curing.

A polymerizable monomer other than (meth)acrylic acid, benzyl (meth)acrylate or benzyl (meth)acrylate derivative, for example, α-position such as styrene, vinyl toluene or α-methylstyrene Or a polymerizable styrene derivative substituted in an aromatic ring; propylene phthalamide such as diacetone acrylamide Ethyl alcohol esters such as vinyl n-butyl ester; alkyl (meth)acrylate, cycloalkyl (meth)acrylate, decyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, ( Methyl acrylate borneol ester, adamantyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylamino (meth) acrylate Ethyl ester, glycidyl (meth)acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, etc. (meth) acrylate; α-bromo (meth)acrylic acid, α-chloro(meth)acrylic acid, β-furyl (meth)acrylic acid, β-styryl (meth)acrylic acid, etc. (methyl) Acrylic acid derivative; maleic acid derivative of maleic acid, maleic anhydride, monomethyl maleate, monoethyl maleate, monoisopropyl maleate; fumaric acid, cinnamic acid, α- Organic acid derivatives such as cyanocinnamic acid, itaconic acid, crotonic acid and propiolic acid, and acrylonitrile. These may be used alone or in combination of two or more.

(A) The binder polymer may further contain a structural unit based on styrene or a derivative thereof from the viewpoint of improving the resolution, adhesion, and peeling properties in a well-balanced manner. (A) When the binder polymer contains a structural unit based on styrene or a derivative thereof, the content thereof is 100 parts by mass based on the total mass of the component (A) from the viewpoints of resolution, adhesion, and peeling characteristics. Good for 5 to 65 parts by mass. In addition, the content is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, still more preferably 15 parts by mass or more, and particularly preferably 20 parts by mass or more, from the viewpoint of further improving the resolution and the adhesion. Good is 30 parts by mass or more. Further, from the viewpoint of further improving the peeling property, the content is preferably 65 parts by mass or less, more preferably 60 parts by mass or less. More preferably, it is 55 mass parts or more, and especially preferably 50 mass parts or less.

(A) The binder polymer preferably further contains a structural unit based on an alkyl (meth)acrylate from the viewpoint of improving alkali developability and peeling properties. (A) When the binder polymer contains a structural unit based on an alkyl (meth)acrylate, the content is preferably 100 parts by mass based on the total mass of the component (A) from the viewpoint of alkali developability and peeling properties. It is 1 to 50 parts by mass, more preferably 2 to 30 parts by mass, still more preferably 3 to 20 parts by mass. The content is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and still more preferably 3 parts by mass or more from the viewpoint of further improving the peeling property. The content is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, and still more preferably 20 parts by mass or less from the viewpoint of further improving the resolution and adhesion after alkali development.

The alkyl (meth)acrylate is, for example, a compound represented by the following general formula (2). In the formula (2), R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents an alkyl group having 1 to 12 carbon atoms.

The alkyl group having 1 to 12 carbon atoms represented by R ⁵ in the general formula (2) may, for example, be a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a decyl group or a fluorenyl group. Base, eleven base, dodecyl and these structural isomers. From the viewpoint of further improving the peeling property, the alkyl group is preferably a carbon number of 4 or less.

The compound represented by the above general formula (2) is, for example, methyl (meth)acrylate, ethyl (meth)acrylate or propyl (meth)acrylate, ( Methyl)butyl acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate , (meth) methacrylate, decyl (meth) acrylate, eleven (meth) acrylate, dodecyl (meth) acrylate. These may be used alone or in combination of two or more.

(A) The weight average molecular weight (Mw) of the binder polymer is measured by gel permeation chromatography (hereinafter referred to as "GPC") (calculated using a calibration curve of standard polystyrene), preferably 10,000~ 100000. In addition, from the viewpoint of improving the liquid resistance (adhesiveness) of the cured product of the photosensitive resin composition, the Mw of the binder polymer is preferably 10,000 or more, more preferably 20,000 or more, still more preferably 25,000 or more. The Mw of the binder polymer is preferably 100,000 or less, more preferably 80,000 or less, and still more preferably 70,000 or less from the viewpoint of excellent alkali developability.

(A) The acid value of the binder polymer is preferably from 100 to 250 mgKOH/g. Further, from the viewpoint of improving the alkali developability, the acid value of the binder polymer is preferably 100 mgKOH/g or more, more preferably 120 mgKOH/g or more, still more preferably 140 gKOH/g or more, and particularly preferably 150 mgKOH/g or more. Further, from the viewpoint of excellent liquid resistance (adhesion), the acid value of the binder polymer is preferably 250 mgKOH/g or less, more preferably 230 mgKOH/g, still more preferably 220 mgKOH/g, and particularly preferably 210 mgKOH. /g. When performing solvent development, it is preferred to prepare a polymerizable monomer having a carboxyl group such as (meth)acrylic acid in a small amount.

(A) The dispersity (Mw/Mn) of the binder polymer is preferably from 1.0 to 3.0, more preferably from 1.0 to 2.0. From the viewpoint of excellent adhesion and resolution Preferably, it is 3.0 or less, More preferably, it is 2.0 or less.

(A) The binder polymer may have a photosensitive property group for light having a wavelength in the range of 350 to 440 nm in its molecule, if necessary.

(A) Adhesive Polymer One type of binder polymer may be used alone or two or more types of binder polymers may be used in any combination. When the binder polymer is used in combination of two or more kinds, for example, two or more types of copolymer polymers having different copolymerization components (including different monomers as a copolymerization component) and two or more types of different weight average molecular weights are used. A binder polymer, a binder polymer of two or more types having different degrees of dispersion, and the like. Further, a polymer having a plurality of morphological molecular weight distributions described in JP-A-H11-327137 can also be used.

The content of the component (A) (the binder polymer) is preferably 30 to 70 parts by mass based on 100 parts by mass of the total of the components (A) and (B). From the viewpoint of imparting film properties, it is preferably 30 parts by mass or more, more preferably 35 parts by mass or more, and still more preferably 40 parts by mass or more. In addition, from the viewpoint of excellent sensitivity and resolution, it is preferably 70 parts by mass or less, more preferably 65 parts by mass or less, still more preferably 60 parts by mass or less.

[(B) component: photopolymerizable compound]

The photopolymerizable compound of the component (B) contains a compound represented by the following general formula (1).

〔化3〕

In the above general formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a methyl group. The a, b, and c systems of the repeating unit of the oxyethylene "-(OC ₂ H ₄ )-" each independently represent an integer of 1 to 48. However, the total number (a+b+c) is 6 to 50, and from the viewpoint of further improving the resolution, the adhesion, and the shape of the photoresist, it is preferably 9 to 45, more preferably 12 to 39, still more preferably 15 ~36.

The compound represented by the above general formula (1) is, for example, TMPT21E (R ¹ = R ² = R ³ = methyl, a + b + c = 21), TMPT30E (R ¹ = R ² = R ³ = methyl, a +b+c=30) (Hitachi Chemical Industry Co., Ltd., product name).

The content of the compound represented by the general formula (1) is improved from the viewpoint of improving the resolution, the adhesion, the resist shape, and the peeling property after curing in a well-balanced manner, and is 100 parts by mass based on the total mass of the component (B). Preferably, it is 5 to 50 parts by mass, more preferably 10 to 40 parts by mass.

(B) The photopolymerizable compound preferably contains the compound represented by the above formula (1) and the bisphenol A (methyl group) from the viewpoint of improving alkali developability, resolution, and peeling properties after curing. ) acrylate compound.

The bisphenol A-based (meth) acrylate compound is, for example, 2,2-bis(4-((meth)propenyloxypolyethoxy)phenyl)propane, 2,2-bis ( 4-((meth)acryloxypolypropoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxypolybutoxy)phenyl)propane, 2,2 - bis(4-((meth)acryloxypolyethoxypolypropyloxy)phenyl)propane or the like. Among them, 2,2-bis(4-((meth)propenyloxypolyethoxy)phenyl)propane is preferred from the viewpoint of improving the resolution and the peeling property.

2,2-bis(4-((meth)propenyloxypolyethoxy)phenyl)propane is, for example, 2,2-bis(4-((methyl)propenyloxydiethoxy)) Phenyl)propane, 2,2-bis(4-((meth)propenyloxytriethoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxy) Ethoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxypentaethoxy)phenyl)propane, 2,2-bis(4-((meth)propene) Decyloxyhexaethoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxyheptaethoxy)phenyl)propane, 2,2-bis(4-(( Methyl)propenyloxy octaethoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxynonethoxy)phenyl)propane, 2,2-bis ( 4-((Meth)acryloxymethoxydecaethoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxy)undecyloxy)phenyl)propane, 2 , 2-bis(4-((meth)propenyloxydodecyloxy)phenyl)propane, 2,2-bis(4-((methyl)propenyloxytridecyloxy)) Phenyl)propane, 2,2-bis(4-((meth)propenyloxytetradecyloxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxy) Hexadecane)phenyl)propane, 2,2-bis(4-((meth)propenyloxy) Hexadecane)phenyl)propane and the like. Among them, 2,2-bis(4-((meth)acryloxy)polyethoxy) The number of oxyethylene groups in one molecule of phenyl)propane is preferably from 4 to 20, more preferably from 8 to 15.

Among these, 2,2-bis(4-(methacryloxypentapentaethoxy)phenyl)propane is commercially available as BPE-500 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name) or FA- 321M (made by Hitachi Chemical Co., Ltd., trade name). Further, 2,2-bis(4-(methacryloxylpentadecyl hexadecyloxy)phenyl)propane is commercially available as BPE-1300 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name). These can be used individually or in combination of 2 or more types.

2,2-bis(4-((meth)propenyloxypolypropoxy)phenyl)propane such as 2,2-bis(4-((meth)propenyloxydipropoxy)benzene) Propane, 2,2-bis(4-((meth)propenyloxytripropoxy)phenyl)propane, 2,2-bis(4-((methyl)propenyloxytetrapropyl) Oxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxypentapropyloxy)phenyl)propane, 2,2-bis(4-((methyl)propene oxime) Ethyl hexapropoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxy)-propenyloxy)phenyl)propane, 2,2-bis(4-((A) Acryloxy octyloxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxynonylpropoxy)phenyl)propane, 2,2-bis (4) -((Meth)propenyloxydapoxy)phenyl)propane, 2,2-bis(4-((methyl)propenyloxyundecyloxy)phenyl)propane, 2, 2-bis(4-((meth)propenyloxydipyloxy)phenyl)propane, 2,2-bis(4-((methyl)propenyloxytridecyloxy)benzene Propane, 2,2-bis(4-((meth)propenyloxytetradecyloxy)phenyl)propane, 2,2-double (4-((Methyl)propenyloxypentadecapropoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxyhexadecane)phenyl)propane .

2,2-bis(4-((meth)propenyloxypolyethoxypolypropoxy)phenyl)propane, for example, 2,2-bis(4-((methyl)propenyloxy) Oxylopropoxy)phenyl)propane, 2,2-bis(4-((meth)propenyloxytetraethoxytetrapropoxy)phenyl)propane, 2,2-bis(4) -((Meth)acryloxy hexaethoxyhexapropyloxy)phenyl)propane.

The content of the component (B) containing a bisphenol A-based (meth) acrylate compound is preferably 20 to 80 parts by mass, more preferably 30 to 70 parts by mass, per 100 parts by mass of the total mass of the component (B).

Further, the component (B) preferably further contains a poly(oxy)oxyethylene chain and a (poly)oxypropylene chain in the molecule from the viewpoint of improving the flexibility of the cured product (cured film) of the photosensitive resin composition. Alkylene glycol di(meth)acrylate.

The polyalkylene glycol di(meth) acrylate is preferably a (poly)oxyethylene chain and a (poly)oxypropylene chain ((poly)oxypropylene) chain having an intramolecular (poly)oxyalkyl chain or (poly)oxypropylene chain). In addition, the polyalkylene glycol di(meth)acrylate may further comprise a (poly)oxy-n-butene chain, a (poly)oxyisobutylene chain, a (poly)oxyn-pentene chain, a (poly)oxyhexene chain. Or a (poly)oxyalkylene chain having a carbon number of 4 to 6 or the like such a structural isomer.

In the intramolecular phase of the polyalkylene glycol di(meth)acrylate, the (poly)oxyethylene chain and the (poly)oxypropylene chain may be present in a continuous block, respectively, or A random way exists. Further, in the (poly)oxypropylene chain, the propylene-based secondary carbon may be bonded to the oxygen atom, and the first-order carbon may be bonded to the oxygen atom.

The polyalkylene glycol di(meth)acrylate is particularly preferably a compound represented by the following general formula (3), (4) or (5). These may be used alone or in combination of two or more.

In the above formulae (3), (4) and (5), R each independently represents a hydrogen atom or a methyl group, EO represents an oxyethylene group, and PO represents an oxypropylene group. m ₁ , m ₂ , m ₃ and m ₄ represent a repeating unit of a structural unit composed of an oxyethylene group, and n ₁ , n ₂ , n ₃ and n ₄ represent a repeating unit of a structural unit composed of an oxypropylene group, The total number of repeating units of oxyethylene groups m ₁ + m ₂ , m ₃ and m ₄ (average value) are each independently representing an integer from 1 to 30, and the total number of repeating units of oxypropylene groups n ₁ , n ₂ + n ₃ and n ₄ (Average) is an integer representing 1 to 30 independently.

In the compound represented by the above general formula (3), (4) or (5), the total number of repeating units of the oxyethylene group m ₁ + m ₂ , m ₃ and m ₄ is an integer of 1 to 30, and preferably 1 to An integer of 10, more preferably an integer from 4 to 9, more preferably an integer from 5 to 8. From the viewpoint of excellent resolution, adhesion, and resist shape, it is preferably 30 or less, more preferably 10 or less, still more preferably 9 or less, and particularly preferably 8 or less.

Further, the total number of repeating units of the oxypropylene group n ₁ , n ₂ + n ₃ and n ₄ are integers of 1 to 30, and preferably an integer of 5 to 20, more preferably an integer of 8 to 16, more preferably 10 An integer of ~14. From the viewpoint of excellent resolution and excellent sludge reduction, it is preferably 30 or less, more preferably 20 or less, still more preferably 16 or less, and particularly preferably 14 or less.

The compound represented by the formula (3) is, for example, a vinyl compound of R = methyl group, m ₁ + m ₂ = 6 (average value), and n ₁ = 12 (average value) (manufactured by Hitachi Chemical Co., Ltd., trade name "FA-023M") and so on. The compound represented by the formula (4) is, for example, a vinyl compound having R = methyl group, m ₃ = 6 (average value), and n ₂ + n ₃ = 12 (average value) (manufactured by Hitachi Chemical Co., Ltd., trade name "FA-024M") and so on. The compound represented by the formula (5) is, for example, a vinyl compound having R = a hydrogen atom, m ₄ = 1 (average value), and n ₄ = 9 (average value) (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name "NKester HEMA"-9P") and so on. These may be used alone or in combination of two or more.

When the component (B) contains a polyalkylene glycol di(meth)acrylate having a (poly)oxyethylene chain and a (poly)oxypropylene chain in the molecule, the total mass of the photopolymerizable compound relative to (B) is 100. The mass portion is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass.

The component (B) may contain a photopolymerizable compound other than the above. The photopolymerizable compound other than the above has at least one ethyl group in the molecule. The unsaturated bond is not particularly limited, and examples thereof include a compound obtained by reacting a polyhydric alcohol with an α,β-unsaturated carboxylic acid, and an amine having a (meth) acrylate compound having an urethane bond in the molecule. Ethyl carbomer monomer, nonylphenoxy polyethylene oxyacrylate, phthalic acid compound, alkyl (meth) acrylate, reaction of glycidyl group-containing compound with α, β-unsaturated carboxylic acid And the compound obtained. These may be used alone or in combination of two or more.

A compound obtained by reacting a polyhydric alcohol with an α,β-unsaturated carboxylic acid, for example, a polyethylene glycol di(meth)acrylate having a vinyl group amount of 2 to 14, and a propylene group having a number of 2 to 14 Polypropylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO modified trimethylolpropane tri(methyl) Acrylate (the total number of repeating units of oxyethylene groups is 1 to 5), PO modified trimethylolpropane tri(meth)acrylate, EO, PO modified trimethylolpropane tri(meth)acrylate , tetramethylol methane tri (meth) acrylate, tetramethylol methane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate. These may be used alone or in combination of two or more. "EO modification" means a compound having a block structure of a (poly)oxyethylene chain (polyoxyethylated compound), and "PO modification" means a compound having a block structure of a (poly)oxypropylene chain ( "Polyoxypropylene compound", "EO, PO modified" means a compound having a block structure of a (poly)oxyethylene chain and a (poly)oxypropylene chain (polyoxyethylated and polyoxypropylene compound) .

(Meth) acrylate compound having a urethane bond in the molecule Examples of the material include a (meth)acrylic monomer having a OH group at the β-position and a diisocyanate compound (isophoric diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, 1,6- Addition reactant of hexamethylene diisocyanate, etc., tris((meth)propenyloxytetraethylene glycol isocyanate) hexamethylene trimer isocyanate, EO modified ethyl urethane di(methyl) ) acrylate, EO, PO modified urethane di(meth) acrylate. The EO-modified urethane di(meth) acrylate is, for example, UA-11 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name). Further, EO, PO modified urethane di(meth) acrylate is, for example, UA-13 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name). These may be used alone or in combination of two or more.

The component (B) may further contain a photopolymerizable compound having one ethylenically unsaturated bond in the molecule. Examples of the photopolymerizable compound having one ethylenically unsaturated bond in the molecule include the above-described mercaptophenoxypolyethoxy acrylate, phthalic acid-based compound, and alkyl (meth)acrylate. Among them, a nonylphenoxypolyethoxy acrylate or a phthalic acid-based compound is preferred from the viewpoint of improving the resolution, the adhesion, the resist shape, and the peeling property after curing in a well-balanced manner.

Nonylphenoxy polyethylene oxyacrylates are, for example, nonylphenoxytriethyleneoxyacrylate, nonylphenoxytetraethyleneoxyacrylate, mercaptophenoxypentaethyleneoxyacrylate, mercaptophenoxy Ethylene hexaoxy acrylate, nonyl phenoxy hexaethylene oxy acrylate, nonyl phenoxy octaethylene oxy acrylate, nonyl phenoxy hexaethylene oxy acrylate, nonyl phenoxy pentene oxy acrylate , nonylphenoxy eleven ethylene oxy acrylate and the like. Such can Use alone or in combination of two or more.

Examples of the phthalic acid-based compound are: γ-chloro-β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate, β-hydroxyethyl-β'-( Methyl)propenyl oxyethyl-phthalate, and β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate. Among them, γ-chloro-β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate is preferred. γ-Chloro-β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate is commercially available as FA-MECH (manufactured by Hitachi Chemical Co., Ltd., trade name). . These compounds may be used alone or in combination of two or more.

As the alkyl (meth)acrylate, the compound represented by the above general formula (2) can be used.

When the component (B) contains a photopolymerizable compound having one ethylenically unsaturated bond in the molecule, the content thereof is improved from the viewpoint of improving the resolution, the adhesion, the resist shape, and the peeling property after curing. The total mass of the component (B) is 100 parts by mass, preferably 1 to 30 parts by mass, more preferably 3 to 25 parts by mass, still more preferably 5 to 20 parts by mass.

The content of the component (B) (photopolymerizable compound) is preferably 30 to 70 parts by mass based on 100 parts by mass of the total of the components (A) and (B). The content of the component (B) is preferably 30 parts by mass or more, more preferably 35 parts by mass or more, and still more preferably 40 parts by mass or more from the viewpoint of improving the sensitivity and the resolution. The content of the component (B) is preferably 70 parts by mass or less, more preferably 65 parts by mass or less, even more preferably 60 parts by mass or less, from the viewpoint of imparting film properties and the shape of the photoresist after curing.

[(C) component: photopolymerization initiator]

With respect to the (C) photopolymerization initiator, it may be selected that the wavelength of light used in the exposure machine matches the wavelength necessary for the function of (C) the photopolymerization initiator, and a conventionally known photopolymerization initiator may be used. There are no special restrictions. (C) Photopolymerization initiators such as benzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-butanone-1,2-methyl- An aromatic ketone such as 1-[4-(methylthio)phenyl]-2-morpholinyl-acetone-1; an anthracene such as an alkyl hydrazine; a benzoin ether compound such as a benzoin alkyl ether a benzoin compound such as a benzoin or an alkyl benzoin; a benzyl derivative such as a benzyl dimethyl ketal; or a dimerization of 2-(o-chlorophenyl)-4,5-diphenylimidazole; 2,4,5-triarylimidazole dimer such as 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer; 9-phenyl acridine, 1,7-(9 An acridine derivative such as 9'-acridinyl)heptane. These may be used alone or in combination of two or more.

(C) The photopolymerization initiator preferably contains a 2,4,5-triarylimidazole dimer from the viewpoint of improving sensitivity and adhesion, and more preferably contains 2-(o-chlorophenyl)-4. 5-diphenylimidazole dimer. The structure of the 2,4,5-triaryl imidazole dimer can be symmetrical or asymmetrical.

The content of the component (C) (photopolymerization initiator) is preferably 0.1 to 10 parts by mass based on 100 parts by mass of the total of the components (A) and (B). The content of the component (C) is preferably 0.1 part by mass or more, more preferably 1 part by mass or more, still more preferably 2 parts by mass or more, and particularly preferably 3 parts by mass, from the viewpoint of excellent sensitivity, resolution, or adhesion. the above. Further, the content of the component (C) is preferably 10 parts by mass or less, more preferably 7 parts by mass or less, still more preferably 6 parts by mass or less, from the viewpoint of excellent shape of the photoresist after curing. 5 parts by mass or less.

[(D) component: sensitizing pigment]

The photosensitive resin composition of the present embodiment may further contain a sensitizing dye of the component (D). The component (D) is not particularly limited as long as it does not affect the effects of the present invention, and a conventionally known sensitizing dye can be used. Specifically, the component (D) is, for example, a dialkylaminobenzophenone, a pyrazoline, an anthraquinone, a coumarin, a xanthone, an oxazole, a benzoxazole, or a thiazole. Classes, benzothiazoles, triazoles, anthraquinones, triazines, thiophenes, naphthyl imines, triarylamines. These may be used alone or in combination of two or more.

In particular, when exposure of the photosensitive resin composition layer is carried out using active light of 390 to 420 nm, the component (D) preferably contains a pyrimide selected from the group consisting of pyrazolines, anthraquinones, and coumarins from the viewpoint of sensitivity and adhesion. At least one of a group and a triarylamine group, more preferably a pyrazoline, an anthracene or a triarylamine.

When the photosensitive resin composition contains the component (D) (sensitizing dye), the content thereof is preferably 0.01 to 10 parts by mass based on 100 parts by mass of the total of the components (A) and (B). The content of the component (D) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and still more preferably 0.1 parts by mass or more from the viewpoint of excellent sensitivity and adhesion. The content of the component (D) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less, from the viewpoint of excellent shape of the photoresist after curing.

[(E) component: amine compound]

The photosensitive resin composition of the present embodiment may contain an amine compound as the component (E) from the viewpoint of further improving the sensitivity. The (E) amine compound is, for example, bis[4-(dimethylamino)phenyl]methane, bis[4-(diethylamino)phenyl]methane, or leuco crystal violet. These may be used alone or in combination of two or more.

When the photosensitive resin composition contains the component (E) (amine compound), the content thereof is preferably 0.01 to 10 parts by mass based on 100 parts by mass of the total of the components (A) and (B). The content of the component (E) is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and still more preferably 0.1 parts by mass or more from the viewpoint of excellent sensitivity. After the formation of the film, in order to prevent the excessive (E) amine compound from being precipitated as a foreign matter, the content of the component (D) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, still more preferably 2 parts by mass or less.

[Other ingredients]

The photosensitive resin composition of the present embodiment may contain a photopolymerizable compound (oxetane compound or the like) having at least one cationically polymerizable cyclic ether group in the molecule, and cationic polymerization initiation. , a dye such as Malachite green, a photochromic agent such as tribromophenylphosphonium or a colorless crystal violet, a thermochromic preventive agent, a plasticizer such as p-toluenesulfonamide, a pigment, a filler, Antifoaming agent, flame retardant, stabilizer, adhesion imparting agent, flattening agent, peeling accelerator, antioxidant, fragrance, imaging agent, thermal crosslinking agent. These may be used alone or in combination of two or more. These contents are relative to the components (A) and (B) The total amount is 100 parts by mass, and each is preferably from 0.01 to 20 parts by mass.

<Solution of photosensitive resin composition>

The photosensitive resin composition of the present embodiment can be dissolved in an organic solvent to form a solution (coating liquid) having a solid content of about 30 to 60% by mass for use. The organic solvent is, for example, methanol, ethanol, acetone, methyl ethyl ketone, cellosolve, ethyl siroli, toluene, N,N-dimethylformamide, propylene glycol monomethyl ether or the like. Mix the solvent.

The coating liquid is applied onto the surface of a metal plate, and after drying, a photosensitive resin composition layer composed of the photosensitive resin composition of the present embodiment can be formed. The metal plate is, for example, an iron-based alloy such as copper, a copper-based alloy, nickel, chromium, iron, or stainless steel, and is preferably copper, a copper-based alloy, or an iron-based alloy.

The thickness of the photosensitive resin composition layer varies depending on the application, and the thickness after drying is preferably about 1 to 100 μm. The surface on the opposite side to the metal plate of the photosensitive resin composition layer may be covered with a protective film. The protective film is, for example, a polymer film of polyethylene, polypropylene or the like.

<Photosensitive element>

As shown in Fig. 1, the photosensitive element 1 of the present invention comprises a support film 2 and a photosensitive resin composition layer 3 formed on the support film 2, and if necessary, can be further protected on the photosensitive resin composition layer 3. Film 4.

The solution of the photosensitive resin composition is applied to the support film 2, and the photosensitive resin composition layer 3 composed of the photosensitive resin composition can be formed on the support film 2 by drying. So you can get support The photosensitive element 1 of the present embodiment of the film 2 and the photosensitive resin composition layer 3 formed on the support film 2.

As the support film 2, a polyester film such as polyethylene terephthalate, a polymer film having heat resistance and solvent resistance such as polypropylene or polyethylene can be used. The thickness of the support film (polymer film) is preferably from 1 to 100 μm, more preferably from 5 to 50 μm, still more preferably from 5 to 30 μm, in consideration of the influence on the strength and the resolution. If the thickness is less than 1 μm, when the support film is peeled off, the support film tends to be easily broken. In order not to affect the resolution, it is preferably 100 μm or less, more preferably 50 μm or less, still more preferably 30 μm or less.

The photosensitive element 1 may have a protective film 4 covering the surface opposite to the support film 2 of the photosensitive resin composition layer 3 as necessary.

The protective film preferably has a bonding strength to the photosensitive resin composition layer of less than the adhesion of the support film to the photosensitive resin composition layer, and is preferably a film having a low Fish Eye. The term "fisheye" refers to a method in which a material is produced by heat-melting, kneading, and extruding, and a film, a non-dissolved substance, an oxidized degradation product, or the like is introduced into a film by a two-axis stretching or a casting method. "Low fisheye" means less of the aforementioned foreign matter in the film.

As the protective film, specifically, a polyester film such as polyethylene terephthalate, a polymer film such as polypropylene, polyethylene, or the like which has heat resistance and solvent resistance can be used. Commercially available products include, for example, Arufun MA-410, E-200C manufactured by Oji Paper Co., Ltd., polypropylene film manufactured by Shin-Etsu Film Co., Ltd., and PS series such as PS-25 manufactured by Teijin Co., Ltd. Alcohol ester film. The protective film can be the same as the support film.

The thickness of the protective film is preferably from 1 to 100 μm, more preferably from 5 to 50 μm. More preferably 5 to 30 μm, and particularly preferably 15 to 30 μm. When the thickness is less than 1 μm, when the photosensitive resin composition layer and the protective film are laminated on the substrate, the protective film tends to be easily broken, and when it exceeds 100 μm, the thickness tends to be insufficient.

When the solution of the photosensitive resin composition is applied to the support film, it can be a roll coater, a comma coater, a gravure coater, or an air knife coater. A known method such as a die coater or a coating bar is carried out.

The drying of the above solution is preferably carried out at 70 to 150 ° C for 5 to 30 minutes. In addition, from the viewpoint of preventing the diffusion of the organic solvent in the subsequent step, the amount of the residual organic solvent in the photosensitive resin composition after drying is preferably 2 parts by mass or less.

The thickness of the photosensitive resin composition layer of the photosensitive element varies depending on the application, but the thickness after drying is preferably from 1 to 100 μm, more preferably from 1 to 50 μm, still more preferably from 5 to 40 μm. When the thickness is less than 1 μm, coating tends to be difficult in the industry, and when it exceeds 100 μm, adhesion and resolution tend to be insufficiently obtained.

The transmittance of the photosensitive resin composition layer to ultraviolet rays is preferably 5 to 75% for ultraviolet rays having a wavelength of 405 nm. From the viewpoint of excellent adhesion, the transmittance is preferably 5% or more, more preferably 10% or more, still more preferably 15% or more. From the viewpoint of excellent resolution, it is preferably 75% or less, more preferably 65% or less, still more preferably 55% or less.

The above transmittance can be measured by a UV spectrometer. The UV spectrometer is, for example, a Model 228A W beam spectrophotometer manufactured by Hitachi, Ltd., a joint stock company.

The photosensitive element may further have an intermediate layer of a buffer layer, an adhesive layer, a light absorbing layer, a gas barrier layer, or the like.

The obtained photosensitive element can be stored in a sheet shape or wound in a roll shape on a winding core. When winding into a roll shape, it is preferable to wind up so that a support film may be the outer side. The core of the core is, for example, a plastic such as a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyvinyl chloride resin, or an ABS resin (acrylonitrile-butadiene-styrene copolymer). The end surface of the roller-shaped photosensitive element roll obtained as described above is preferably provided with an end face spacer from the viewpoint of end face protection, and a moisture-proof end face spacer is preferably provided from the viewpoint of preventing edge fusion. The baling method is preferably packaged in a black sheet having a low moisture permeability.

<Formation method of photoresist pattern>

The photoresist pattern can be formed using the photosensitive resin composition of the present invention. The method for forming a photoresist pattern of the present embodiment includes: (i) a lamination step of laminating a photosensitive resin composition layer composed of the photosensitive resin composition on a substrate; (ii) a photosensitive resin a predetermined portion of the composition layer irradiating the active light to expose and cure the predetermined portion; and (iii) removing a portion other than the predetermined portion of the photosensitive resin composition layer from the substrate, on the substrate A developing step of forming a photoresist pattern composed of a cured product of a photosensitive resin composition.

(i) lamination step

First, a photosensitive resin composed of a photosensitive resin composition is composed The layer is laminated on the substrate. As the substrate, a substrate (circuit forming substrate) having an insulating layer and a conductor layer formed on the insulating layer can be used.

The photosensitive resin composition layer is laminated on the substrate, and for example, the protective film of the photosensitive element is removed, and then the photosensitive resin composition layer of the photosensitive element is heated and pressed against the substrate. Thereby, a laminate formed by sequentially laminating the substrate, the photosensitive resin composition layer, and the support film can be obtained.

This layer of cooperation is preferred under reduced pressure from the standpoint of adhesion and compliance. The heating of the photosensitive resin composition layer and/or the substrate at the time of pressure bonding is preferably carried out at a temperature of 70 to 130 ° C, and is carried out at a pressure of 0.1 to 1.0 MPa (about 1 to 10 kgf/cm ² ). Adhesion is preferred, but is not limited to such conditions. When the photosensitive resin composition layer is heated to 70 to 130 ° C, it is not necessary to preheat the substrate in advance, but in order to improve the laminate property, the substrate may be preheated.

(ii) Exposure step

Next, a predetermined portion of the photosensitive resin composition layer on the substrate is irradiated with active light rays to expose and cure the predetermined portion. In this case, when the support film which is present on the photosensitive resin composition layer is transparent to the active light, the active light can be irradiated through the support film, but when the support film is light-shielding, the photosensitive resin composition is removed after the support film is removed. The layer illuminates the active light.

The exposure method is a method of irradiating an active light onto an image, for example, by a negative or positive reticle pattern called an artwork (mask exposure) law). It is also possible to use a direct drawing exposure method such as LDI (Laser Direct Imaging) exposure method or DLP (Digital Light Processing) exposure method to irradiate active light rays in an image form.

As the light source of the active light, a known light source such as a carbon arc lamp, a mercury vapor arc lamp, a high pressure mercury lamp, a xenon lamp, a gas laser such as an argon laser, a solid laser such as a YAG laser, or the like can be used. A semiconductor laser or the like that effectively emits ultraviolet light, visible light, or the like.

The wavelength of the active light (exposure wavelength) is preferably in the range of 350 to 420 nm, more preferably in the range of 390 to 420 nm, from the viewpoint of obtaining the effect of the present invention.

(iii) imaging steps

A portion other than the predetermined portion of the photosensitive resin composition layer is removed from the substrate, and a resist pattern composed of a cured product of the photosensitive resin composition is formed on the substrate. When the support film is present on the photosensitive resin composition layer, a portion other than the predetermined portion (exposed portion) (unexposed portion) (developing) is removed after the support film is removed. The development methods include wet imaging and dry imaging, but wet imaging is more widely used.

In the case of wet development, development is carried out by a known development method using a developing liquid corresponding to the photosensitive resin composition. The developing method includes, for example, a method using an immersion method, a stirring method, a spray method, rinsing, brushing, blade coating, shaking immersion, etc., and the high-pressure spray method is optimal from the viewpoint of improving the resolution. Further, two or more methods may be combined to perform development.

The developing solution is, for example, an alkaline aqueous solution, a water-based developing solution, or an organic solvent system. Imaging liquid, etc.

When an alkaline aqueous solution is used as a developing solution, it is safe and stable, and has good workability. As the base of the alkaline aqueous solution, for example, an alkali hydroxide such as lithium, sodium or potassium hydroxide; a carbonate such as lithium, sodium, potassium or ammonium carbonate or a bicarbonate; a base such as potassium phosphate or sodium phosphate; Metal phosphate; alkali metal pyrophosphate such as sodium pyrophosphate or potassium pyrophosphate.

The alkaline aqueous solution is preferably a dilute solution of sodium carbonate of 0.1 to 5% by mass, a dilute solution of 0.1 to 5% by mass of potassium carbonate, a dilute solution of 0.1 to 5% by mass of sodium hydroxide, and a content of 0.1 to 5% by mass. A dilute solution of sodium borate. The pH of the alkaline aqueous solution is preferably in the range of 9 to 11, and the temperature is adjusted in accordance with the alkali developability of the photosensitive resin composition layer. A surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, and the like can be added to the alkaline aqueous solution.

The aqueous developing solution may be, for example, a developing liquid composed of water or an aqueous alkaline solution and one or more organic solvents. Here, the base of the alkaline aqueous solution includes, in addition to the foregoing, borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl. -1,3-propanediol, 1,3-diaminopropanol-2, morpholine. The pH of the aqueous imaging solution is preferably as small as possible within the range of adequate imaging, preferably from pH 8 to 12, more preferably from pH 9 to 10.

The organic solvent used in the aqueous developing solution is, for example, acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethanol, isopropanol, butanol, diethylene glycol monomethyl ether, Diethylene glycol monoethyl ether, diethylene glycol monobutyl ether. These may be used alone or in combination of two or more. The concentration of the organic solvent in the aqueous imaging solution is usually preferably from 2 to 90% by mass, which can be used in combination with alkali Adjust like sex. Further, a surfactant, an antifoaming agent, or the like may be added in a small amount in the aqueous developing solution.

The organic solvent-based developing solution is, for example, 1,1,1-trichloroethane, N-methylpyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, γ-butyl An organic solvent such as a lactone. Among these organic solvents, in order to prevent ignition, it is preferred to add water in the range of 1 to 20% by mass.

After removing the unexposed portion, the photoresist pattern may be further hardened by heating at a temperature of 60 to 250 ° C or an exposure of 0.2 to 10 J/cm ² as necessary.

<Manufacturing method of printed circuit board>

A substrate in which a photoresist pattern is formed by the above method can be manufactured by etching or plating. The formed photoresist pattern is used as a mask, and the substrate is etched or plated with respect to the conductor layer of the substrate.

The etching liquid to be etched is, for example, a copper chloride solution, a ferric chloride solution, an alkaline etching solution, or a hydrogen peroxide etching solution. Among these, from the viewpoint of a good etch factor, a ferric chloride solution is preferably used.

The plating method for plating is, for example, copper plating such as copper sulfate plating or copper pyrophosphate plating; solder plating such as high-throw solder plating; and Watt bath (nickel sulfate-nickel chloride) Nickel plating such as plating or nickel sulfonate; gold plating such as hard gold plating or soft gold plating.

After the etching or plating is completed, for example, the photoresist pattern can be peeled off by an aqueous solution which is more alkaline than the aqueous alkaline solution. The strongly alkaline aqueous solution can be, for example, 1 to 10% by mass of an aqueous sodium hydroxide solution, and 1 to 10% by mass. An aqueous solution of potassium hydroxide. Among them, a 1 to 10% by mass aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution is preferably used, and a 1 to 5% by mass aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution is more preferably used.

The peeling pattern of the resist pattern is, for example, an immersion method, a spray method, or the like, and these may be used singly or in combination. The printed circuit board forming the photoresist pattern may be a multilayer printed circuit board, a printed circuit board which may have a small-diameter through hole, or may have a high-density wiring such as a high-density package substrate and a germanium wafer.

[Examples]

The invention will be specifically described below by way of examples. However, the invention is not limited to the following embodiments.

(A) binder polymer

(A-1)

150 g of methacrylic acid of a polymerizable monomer, 125 g of benzyl methacrylate, 25 g of methyl methacrylate, 200 g of styrene (mass ratio 30/25/5/40) and azobisisobutyronitrile 9.0 g The resulting solution was mixed as "solution a".

A solution obtained by dissolving 1.2 g of azobisisobutyronitrile in 100 g of a mixture of 60 g of cellosolve and 40 g of toluene (mass ratio: 3:2) was referred to as "solution b".

450 g of a mixture of 270 g of methyl sirolimus and 180 g of toluene (mass ratio: 3:2) was placed in a mixer, a reflux condenser, a thermometer, and a drip. The funnel and the nitrogen gas introduction tube were placed in a flask, and a nitrogen gas was blown into the flask while stirring, and the temperature was raised to 80 ° C by heating.

The solution a was added dropwise to the mixed solution in the flask over 4 hours, and the mixture was stirred at 80 ° C for 2 hours while stirring. Next, the solution b was dropped into the mixture in the flask over 10 minutes, and the mixture was stirred at 80 ° C for 3 hours. The solution in the flask was further heated to 90 ° C over 30 minutes, and after incubation at 90 ° C for 2 hours, it was cooled to obtain a solution of the binder polymer (A-1).

The non-volatile content (solid content) of the binder polymer (A-1) was 47.8% by mass, the weight average molecular weight was 30,000, and the acid value was 196 mgKOH/g. The weight average molecular weight is measured by gel permeation chromatography (GPC) and is derived using a calibration curve of standard polystyrene. The conditions for GPC are as follows.

(GPC condition)

Pump: Hitachi L-6000 (manufactured by Hitachi, Ltd., product name)

Column: 3 totals below

Gelpack GL-R420

Gelpack GL-R430

Gelpack GL-R440 (The above is manufactured by Hitachi Chemical Co., Ltd., trade name)

Dissolution: tetrahydrofuran

Measuring temperature: 40 ° C

Flow rate: 2.05mL/min

Detector: Hitachi L-3300 RI (manufactured by Hitachi, Ltd., product name)

(A-2)~(A-6)

The polymerizable monomer (monomer) was obtained by using the materials shown in Table 1 in the mass ratio shown in Table 1, and the binder polymer (A-2) was obtained in the same manner as the solution of the binder polymer (A-1). )~(A-6) solution.

[Preparation of photosensitive resin composition solution]

The components shown in the following Tables 2 and 3 were mixed in the amounts shown in the same table to prepare solutions of the photosensitive resin compositions of Examples 1 to 14 and Comparative Examples 1 and 2. The blending amount of the component (A) shown in Tables 2 and 3 is the mass (solid content) of nonvolatile matter.

The details of the components shown in the above Tables 2 and 3 are as follows.

(B) Photopolymerizable compound

TMPT21 (manufactured by Hitachi Chemical Co., Ltd., trade name): EO modified trimethylolpropane triacrylate (in general formula (1), R ¹ = R ² = R ³ = methyl, a + b + c = 21 (average) compound)

A-TMPT-3EO (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.): EO-modified trimethylolpropane triacrylate (the total number of repeating units of oxyethylene is 3)

FA-321M (manufactured by Hitachi Chemical Co., Ltd., trade name): 2,2-bis(4-(methacryloxypentapentaethoxy)phenyl)propane

BPE-100 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.): EO-modified bisphenol A-based dimethacrylate (the total number of repeating units of oxyethylene is 2.6)

M-114 (manufactured by Toagos Corporation, trade name): 4-n-decylphenoxy octaethylene glycol acrylate

FA-MECH (manufactured by Hitachi Chemical Co., Ltd., trade name): (2-hydroxy-3-chloro)propyl-2-methylpropenyloxyethyl phthalate

FA-024M (manufactured by Hitachi Chemical Co., Ltd., trade name): Compound of the general formula (4), R = methyl group, m ₃ = 6 (average value), n ₂ + n ₃ = 12 (average value)

(C) Photopolymerization initiator

B-CIM (manufactured by Hampford Co., Ltd.): 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole

(D) sensitizing pigment

DBA (made by Kawasaki Chemical Industry Co., Ltd., trade name): 9,10-dibutoxy oxime

PYR-1 (manufactured by Nippon Chemical Industry Co., Ltd., trade name): 1-phenyl-3-(4-isopropylstyryl)-5-(4-isopropylphenyl)pyrazoline

J205 (manufactured by Nippon Distillation Co., Ltd., trade name): a triphenylamine derivative represented by the following formula (9)

(E) amine compound

LCV (made by Yamada Chemical Co., Ltd., trade name): leuco crystal violet

(dye)

MKG (made by Osaka Organic Chemical Industry Co., Ltd., trade name): Malachite Green

[photosensitive element]

The solutions of the photosensitive resin compositions of the above examples and comparative examples were uniformly applied to a polyethylene terephthalate film (manufactured by Teijin Co., Ltd., trade name "HTF-01") having a thickness of 16 μm, and 70 The hot air convection dryer at °C and 110 °C is dried to form a film thickness of 25 μm after drying. A photosensitive resin composition layer. A protective film (trade name "NF-15", manufactured by TAMAPOLY Co., Ltd.) was bonded to the photosensitive resin composition layer to obtain a sequentially laminated polyethylene terephthalate film (support film) and a photosensitive resin. A photosensitive layer constituting the layer and the protective film.

[Laminated substrate]

A copper-clad laminate (manufactured by Hitachi Chemical Co., Ltd., trade name "MCL-E-67") made of a glass epoxy material and a copper foil (thickness: 35 μm) formed on both surfaces thereof has a surface of #600. The grinder of the equivalent brush (manufactured by the company) was ground, washed with water, and dried by air flow. After the copper-clad laminate (hereinafter referred to as "substrate") was heated to 80 ° C by heating, the photosensitive elements of Examples 1 to 14 and Comparative Examples 1 and 2 were laminated on the copper surface of the substrate. The lamination was carried out under the conditions of a temperature of 120 ° C and a lamination pressure of 4 kgf/cm ^{2 so} that the photosensitive resin composition layer of each photosensitive element was adhered to the copper surface of the substrate. Thus, a laminated substrate in which a photosensitive resin composition layer and a polyethylene terephthalate film were laminated on the copper surface of the substrate was obtained.

[Evaluation of sensitivity]

The obtained laminated substrate was left to be cooled, and at a temperature of 23 ° C, a 41-step stage tablet having a concentration range of 0.00 to 2.00, a concentration stage of 0.05, a plate size of 20 mm × 187 mm, and a size of each stage of 3 mm × 12 mm was used. A photo tool is adhered to the polyethylene terephthalate film of the laminated substrate. A direct exposure machine (manufactured by Hitachi Via Mechanics Co., Ltd., trade name "DE-1AH") using a blue-violet laser diode having a wavelength of 405 nm as a light source, and an energy (exposure amount) of 70 mJ/cm ^{2 was used} . The photosensitive resin composition layer was exposed by a mask and a polyethylene terephthalate film. Further, illuminance measurement was performed using an ultraviolet illuminometer (manufactured by Oxtail Motor Co., Ltd., trade name "UIT-150") to which a probe of 405 nm was applied.

After the exposure, the polyethylene terephthalate film was peeled off from the laminated substrate, and the photosensitive resin composition layer was exposed. Then, a 1% by mass aqueous sodium carbonate solution was sprayed at 30 ° C for 24 seconds to remove the unexposed portion. Thus, a cured film composed of a cured product of a photosensitive resin composition is formed on the copper surface of the substrate. The number of remaining segments of the obtained step plate was measured in the form of a cured film, and the sensitivity of the photosensitive resin composition was evaluated. The sensitivity is expressed in the number of segments of the stage plate. The higher the number of segments, the better the sensitivity. The results are shown in Tables 5 and 6.

[Evaluation of resolution and adhesion]

The line width (L) / pitch width (S) (hereinafter referred to as "L/S") is a drawing pattern of 5/5 to 30/30 (unit: μm), and the number of remaining segments of the 41-stage plate becomes The energy of the 11th stage is exposed (drawn) to the photosensitive resin composition layer of the laminated substrate. After the exposure, the same development process as the evaluation of the aforementioned sensitivity was performed.

After the development, the pitch portion (unexposed portion) is completely removed, and in the photoresist pattern formed by the line portion (exposed portion) without bending or missing, the resolution is evaluated by the minimum line width/pitch width value. Sex. Adhesiveness. This number The smaller the value, the better the resolution and the adhesion. The results are shown in Tables 5 and 6.

[Evaluation of photoresist shape]

The above resolution. In the evaluation of the adhesion, the obtained resist shape (the cross-sectional shape of the resist pattern) was observed using a Hitachi scanning electron microscope S-500A. The results are shown in Tables 5 and 6. When the photoresist shape is trapezoidal or inverted trapezoidal, or when the photoresist has a bottom edge to be folded or cracked, the circuit formed by the subsequent etching treatment or plating treatment tends to be short-circuited or broken. Therefore, the shape of the photoresist is preferably rectangular (rectangular), and the photoresist is not folded or cracked at the bottom.

"Cracking" refers to the occurrence of cracks or cracks in the line portion (exposed portion) of the resist pattern or the occurrence of a leak or break in the line portion.

[Evaluation of peeling characteristics]

Each of the photosensitive members was laminated on the copper-clad laminate (substrate), and exposed and developed under the conditions shown in Table 4 to prepare a test piece (40 mm × 50 mm) in which a cured film was formed on the substrate. This test piece was allowed to stand at room temperature (25 ° C) for a day and night, and peeled off under the conditions shown in Table 4. The time from the start of stirring until the cured film was completely peeled off from the substrate was taken as the peeling time. The size of the peeled sheet after peeling was visually observed and evaluated according to the following criteria. The shorter the peeling time, the smaller the peeling sheet size, indicating that the peeling property is better. When the size of the release sheet is a sheet, it is indicated by "L", and when it is 30-40 mm square, it is represented by "M", and when it is smaller than 30 mm square, it is represented by "S". The results are shown in Tables 5 and 6.

As can be seen from Tables 5 and 6, the photosensitive resin compositions of Examples 1 to 14 The sensitivity, resolution, adhesion, photoresist shape, and peeling properties after hardening are all good. However, Comparative Example 1 using a binder polymer having no structural unit based on benzyl (meth) acrylate or benzyl (meth) acrylate derivative, and photopolymerizable compound not containing the general formula (1) The photosensitive resin composition of Comparative Example 2 was inferior to the examples in terms of resolution, adhesion, and photoresist shape.

[Industrial Applicability]

The photosensitive resin composition of the present invention is suitably used as a material for forming a photoresist pattern for a printed circuit board. In particular, since the photosensitive resin composition has good sensitivity, resolution, adhesion, photoresist shape, and peeling property after curing, it is also suitable for forming a photoresist pattern, and the photoresist pattern can be accurately performed. A printed circuit board having a high-density wiring such as a high-density package substrate and a tantalum wafer rewiring is efficiently manufactured.

1‧‧‧Photosensitive components

2‧‧‧Support film

3‧‧‧Photosensitive resin composition layer

4‧‧‧Protective film

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a preferred embodiment of a photosensitive element of the present invention.

Claims (14)

A photosensitive resin composition comprising (A) a binder polymer, (B) a photopolymerizable compound, (C) a photopolymerization initiator, and (D) a sensitizing dye, wherein the photosensitive resin composition is characterized by The (A) binder polymer has a structural unit based on (meth)acrylic acid, and a structural unit based on benzyl (meth) acrylate or benzyl (meth) acrylate derivative; (B) photopolymerization The compound contains the compound represented by the following general formula (1); [In the formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a methyl group, and a, b and c each independently represent an integer of 1 to 48, and the total number of a, b and c is 6~. 50]. The photosensitive resin composition of the first aspect of the invention, wherein the (B) photopolymerizable compound further contains a bisphenol A-based (meth) acrylate compound. The photosensitive resin composition of claim 1 or 2, wherein the (B) photopolymerizable compound further contains one B A compound having an ethylenically unsaturated bond. The photosensitive resin composition of the first or second aspect of the invention, wherein the (B) photopolymerizable compound further contains a polyalkylene glycol having a (poly)oxyethylene chain and a (poly)oxypropylene chain ( Methyl) acrylate compound. The photosensitive resin composition according to claim 1 or 2, wherein the (C) photopolymerization initiator contains a 2,4,5-triarylimidazole dimer. The photosensitive resin composition of claim 1 or 2, further comprising (E) an amine compound. The photosensitive resin composition of claim 1 or 2, wherein the (A) binder polymer further contains a structural unit based on styrene or a styrene derivative. The photosensitive resin composition of claim 1 or 2, wherein the (A) binder polymer further contains a structural unit based on an alkyl (meth)acrylate. The photosensitive resin composition according to claim 1 or 2, wherein the (A) binder polymer has a weight average molecular weight of 10,000 to 100,000. The photosensitive resin composition according to claim 1 or 2, wherein the (A) binder polymer has an acid value of from 100 to 250 mgKOH/g. A photosensitive element characterized by comprising: a support film and any one of claims 1 to 10 formed on the support film A photosensitive resin composition layer composed of the photosensitive resin composition. A method for forming a photoresist pattern, comprising: laminating a photosensitive resin composition layer comprising a photosensitive resin composition according to any one of claims 1 to 10 on a substrate a step of irradiating a predetermined portion of the photosensitive resin composition layer with an active light to expose and cure the predetermined portion; and a portion other than the predetermined portion of the photosensitive resin composition layer on the substrate In addition, a development step of a resist pattern composed of a cured product of a photosensitive resin composition is formed on the substrate. The method for forming a photoresist pattern according to claim 12, wherein the wavelength of the active light is in the range of 390 to 420 nm. A method of manufacturing a printed circuit board, comprising the step of etching or plating a substrate on which a photoresist pattern is formed by the method of claim 12 or 13.