CN101910943B - Layered photosensitive-resin product - Google Patents

Abstract

A layered photosensitive-resin product which includes a photosensitive-resin layer having a thickness of 3-15 mu m and which, despite the small photosensitive-layer thickness, has satisfactory tenting properties even when exposed by direct writing exposure. This layered product upon development gives aggregates which are not oily. The layered photosensitive-resin product comprises superposed layers composed of a base layer and a photosensitive-resin layer. This product is characterized in that the photosensitive-resin layer is made of a photosensitive resin composition and that the photosensitive resin composition comprises (a) 25-64 mass% alkali-soluble resin, (b) a compound having a photopolymerizable unsaturated double bond, and (c) 0.1-20 mass% photopolymerization initiator. The product is further characterized by satisfying the following (i), (ii), and (iii): (i) a specific photopolymerizable unsaturated compound is contained in an amount of 30-55 mass% based on the whole photosensitive resin composition; (ii) the alkali-soluble resin (a) has a weight-average molecular weight of 70,000-220,000 and an acid equivalent of 100-600; and (iii) the photosensitive-resin layer has a thickness of 3-15 mu m.

Description

Photosensitive resin laminate

technical field

The present invention relates to a photosensitive resin laminate in which a photosensitive resin composition developable by an alkaline aqueous solution is laminated on a support layer, a method of forming a resist pattern on a substrate using the photosensitive resin laminate, and the Use of resist patterns. More specifically, it relates to a photosensitive resin composition that provides a suitable resist pattern in the manufacture of printed wiring boards, flexible printed wiring boards, and lead frames for IC chip mounting (hereinafter referred to as lead frames). Frame) manufacturing; metal foil precision processing such as metal mask manufacturing, semiconductor package manufacturing such as BGA (ball grid array package) or CSP (chip size package); TAB (automatic tape carrier bonding: TapeAutomated Bonding) or Manufacture of tape-shaped substrates represented by COF (Chip On Film: a material for mounting semiconductor ICs on thin-film micro-circuit boards); manufacture of semiconductor bumps; ITO electrodes and addressing in the field of flat panel displays Manufacture of components such as electrodes or electromagnetic wave shields.

Background technique

Conventionally, printed wiring boards have been manufactured by photolithography. The so-called photolithography method refers to coating a photosensitive resin composition on a substrate, polymerizing and curing the exposed part of the photosensitive resin composition through pattern exposure, and removing the unexposed part by a developer to form a resist on the substrate. Patterning, performing etching or plating to form a conductive pattern, and then peeling and removing the resist pattern from the substrate, thereby forming a conductive pattern on the substrate.

In the above-mentioned photolithography method, when the photosensitive resin composition is coated on the substrate, any of the following methods can be used: a method of coating a photoresist solution on the substrate and drying it, or coating the substrate with a photoresist solution. A support layer, a layer formed of a photosensitive resin composition (hereinafter also referred to as "photosensitive resin layer"), and a photosensitive resin laminate (hereinafter also referred to as "anti-corrosion dry layer") of a protective layer are sequentially laminated on it. Membrane".) method. And in the manufacture of printed circuit boards, most of the latter dry resist films are used.

A brief description of the method for manufacturing a printed circuit board using the above-mentioned dry resist film is as follows.

First, when the dry resist film has a protective layer such as a polyethylene film, it is peeled off from the photosensitive resin layer. Next, a photosensitive resin layer and a support layer are laminated in this order on a substrate such as a copper-clad laminate using a laminator. Next, the photosensitive resin layer was exposed to ultraviolet rays including i-rays (365 nm) emitted from an ultra-high pressure mercury lamp through a photomask having a circuit pattern, whereby the exposed portion was polymerized and cured. The support layer, such as polyethylene terephthalate, is then peeled off. Then, the unexposed portion of the photosensitive resin layer is removed by dissolving or dispersing a developing solution, such as a weakly alkaline aqueous solution, so that a resist pattern is formed on the substrate.

Using the resist pattern on the substrate formed in this way, as a method of forming a metal conductor pattern, it is roughly divided into two methods, the method of removing the metal part not covered by the resist by etching and the method of plating the metal part. method. Especially recently, starting from the simple aspect of the process, the former method is often used.

In the method of removing the metal portion by etching, as for through-holes (via holes) for substrates and via holes for interlayer connection, the metal inside the holes is prevented from being etched by covering with a cured resist film. This process method is called the tenting method. In the etching process, for example, cupric chloride, ferric chloride, and cuproammine complex solutions can be used.

With the miniaturization of the circuit spacing in printed wiring boards in recent years, in order to produce fine-pitch patterns with good yield, high resolution and high hole-covering properties are required for the resist dry film. As a method of improving the resolution, it can be easily improved by making the resist dry film thinner. On the contrary, the resistance to the physical external force of the film caused by the spray of the developing process and the etching process is weakened, and there are There is a problem that via holes and via holes cannot be protected in the development process and etching process (poor capping property).

Patent Document 1 discloses a photoresist excellent in that there are many trifunctional monomers among the unsaturated compounds in the photosensitive resin composition. However, only the ratio of the trifunctional monomer in the unsaturated compound is described, and there is a problem that the pore capping property is not excellent within a certain range. Patent Document 1 will be described later in a comparative example.

Patent Document 2 discloses an excellent photoresist utilizing a tetrafunctional monomer as an unsaturated compound in a photosensitive resin composition. However, there is a problem that capping properties are not excellent in direct drawing exposure using these.

Patent Document 3 discloses an excellent photoresist utilizing a trifunctional monomer among unsaturated compounds in a photosensitive resin composition. However, there is a problem that the hole capping property is not excellent in the direct drawing exposure by the film using these.

However, when these polyfunctional monomers are included in a large amount in the photosensitive resin composition, there is also a problem that oily aggregates are generated at the time of image development.

Therefore, even in direct drawing exposure, the capping property is good, and the aggregates at the time of development are not oily, and there are few powdery aggregates.

Patent Document 1: Japanese Patent Application Laid-Open No. 11-119422

Patent Document 2: Japanese Patent Laid-Open No. 2000-347400

Patent Document 3: Japanese Patent Laid-Open No. 2002-228871

Contents of the invention

The problem to be solved by the invention

An object of the present invention is to provide a photosensitive resin laminate in which even when the thickness of the photosensitive resin layer is as thin as 3 to 15 μm, the hole-clogging property is good even when exposed by direct drawing exposure, and when no development occurs oily aggregates, and less powdery aggregates.

solutions to problems

The above-mentioned problems can be achieved by the following technical solutions of the present invention.

That is, the content of the present invention is as follows.

1. A photosensitive resin laminate, characterized in that it is a photosensitive resin laminate formed by laminating at least a support layer and a photosensitive resin layer, the photosensitive resin layer being formed from a photosensitive resin composition, The photosensitive resin composition comprises at least:

(a) Alkali-soluble resin 25-64 mass %,

(b) photopolymerizable compounds having unsaturated double bonds,

(c) 0.1-20% by mass of photopolymerization initiator,

and further satisfy the following (i), (ii) and (iii):

(i) As the (b) photopolymerizable compound having an unsaturated double bond, it contains 30 to 55% by mass of a compound selected from the group represented by the following general formula (I) with respect to the total amount of the photosensitive resin composition. At least one photopolymerizable unsaturated compound in the group consisting of a compound and a compound represented by the following general formula (II);

(ii) the weight-average molecular weight of the (a) alkali-soluble resin is 70,000-220,000, and the acid equivalent is 100-600;

(iii) the thickness of the photosensitive resin layer is 3-15 μm,

(chemical formula 1)

(In the formula, R ₁ , R ₂ and R ₃ are each independently H or CH ₃ , n ₁ , n ₂ , n ₃ and n ₄ are each independently an integer of 0 to 4, and may also be 0 at the same time. W is A group represented by CH ₃ or OH.)

(chemical formula 2)

(In the formula, R ₅ , R ₆ , R ₇ and R ₈ are each independently H or CH ₃ , m ₁ , m ₂ , m ₃ and m ₄ are each independently an integer of 0 to 4, and can also be 0 at the same time .)

2. The photosensitive resin laminate according to the above 1, wherein, as the (b) photopolymerizable compound having an unsaturated double bond, 35 to 55 % by mass of at least one photopolymerizable unsaturated compound selected from the group consisting of the compound represented by the general formula (I) and the compound represented by the general formula (II).

3. The photosensitive resin laminate according to 1 or 2 above, wherein (c) the photopolymerization initiator is 9-phenylacridine.

4. The photosensitive resin laminate according to any one of 1 to 3 above, wherein the ratio of the above-mentioned (a) alkali-soluble resin to the total amount of the photosensitive resin composition is A mass %, the above-mentioned (b) When the ratio of the compound which has a photopolymerizable unsaturated double bond is B mass %, A/B is 1.1-1.3.

5. A method for forming a resist pattern, comprising a lamination step of laminating the photosensitive resin layer of the photosensitive resin laminate according to any one of 1 to 4 above on a substrate, and an exposure step of exposing ultraviolet rays , Remove the unexposed part of the development process.

6. The method for forming a resist pattern according to 5 above, wherein exposure is performed by direct drawing in the exposure step.

7. A method for producing a conductor pattern, comprising: using a copper-clad laminate as a substrate, etching or plating the substrate on which the resist pattern is formed by the method described in 5 or 6 above.

8. A method of manufacturing a printed wiring board, characterized in that a metal-clad insulating board is used as a substrate, and the substrate on which the resist pattern is formed by the method described in any one of 4 to 7 above is etched or plated , stripping the resist pattern.

9. A method for manufacturing a lead frame, comprising using a metal plate as a substrate, etching the substrate on which the resist pattern is formed by the method described in any one of 4 to 8 above, and peeling off the resist pattern.

10. A method of manufacturing a semiconductor package, characterized in that a wafer on which a circuit of a large-scale integrated circuit has been formed is used as a substrate, and a substrate having a resist pattern formed by the method described in any one of 4 to 9 above is used Plating is performed, and the resist pattern is peeled off.

11. A method for manufacturing a base material with a concavo-convex pattern, characterized in that glass ribs are used as the base plate, and the base plate on which the resist pattern is formed by the method described in any one of the above 4 to 10 is processed by a sandblasting process , stripping the resist pattern.

The effect of the invention

The photosensitive resin laminate of the present invention has the effect that even when the photosensitive resin layer is as thin as 3 to 15 μm in thickness, the hole-clogging property is good even when exposed by direct drawing exposure, and oily accumulation during development does not occur. matter, and less powdery aggregates.

Detailed ways

The present invention will be specifically described below.

<Photosensitive resin laminate>

The photosensitive resin laminate of the present invention is characterized in that it is a photosensitive resin laminate in which at least a support layer and a photosensitive resin layer are laminated, the photosensitive resin layer is formed of a photosensitive resin composition, and the The photosensitive resin composition at least includes:

(a) Alkali-soluble resin 25-64 mass %,

(b) photopolymerizable compounds having unsaturated double bonds,

(c) 0.1-20% by mass of photopolymerization initiator,

and further satisfy the following (i), (ii) and (iii):

(i) As the (b) photopolymerizable compound having an unsaturated double bond, it contains 30 to 55% by mass of a compound selected from the group represented by the following general formula (I) with respect to the total amount of the photosensitive resin composition. At least one photopolymerizable unsaturated compound in the group consisting of a compound and a compound represented by the following general formula (II);

(ii) the weight-average molecular weight of the (a) alkali-soluble resin is 70,000-220,000, and the acid equivalent is 100-600;

(iii) the thickness of the photosensitive resin layer is 3-15 μm,

[chemical formula 3]

(In the formula, R ₁ , R ₂ , and R ₃ are each independently H or CH ₃ , and n ₁ , n ₂ , n ₃ , and n ₄ are each independently an integer of 0 to 4, and may be 0 at the same time. W is a group represented by CH ₃ or OH.)

[chemical formula 4]

(In the formula, R ₅ , R ₆ , R ₇ and R ₈ are each independently H or CH ₃ , m ₁ , m ₂ , m ₃ and m ₄ are each independently an integer of 0 to 4, and can also be 0 at the same time .)

When describing the compounding quantity of each component in a photosensitive resin composition, the compounding quantity of each component is described by mass % based on the solid content total amount in a photosensitive resin composition.

(a) Alkali-soluble resin

The alkali-soluble resin refers to a carboxyl group-containing vinyl resin, for example, a copolymer of (meth)acrylic acid, (meth)acrylate, (meth)acrylonitrile, (meth)acrylamide, or the like.

(a) The alkali-soluble resin preferably contains a carboxyl group and has an acid equivalent of 100-600. The so-called acid equivalent means the mass of a linear polymer having 1 equivalent of carboxyl group therein. The acid equivalent is more preferably from 250 to 450. It is preferably 100 or more from the viewpoint of improving development resistance, resolution and adhesion, and preferably 600 or less from the viewpoint of improving developability and peelability. The acid equivalent was measured by the potentiometric titration method using 0.1 mol/L sodium hydroxide using the Hiranuma Sangyo Co., Ltd. Hiranuma automatic titration device (COM-555).

The (a) alkali-soluble resin used in the present invention preferably has a weight average molecular weight of not less than 70,000 and not more than 220,000. From the viewpoint of improving developability, it is preferably 220,000 or less. From the viewpoint of capping properties and properties of aggregates, the weight average molecular weight is preferably 70,000 or more. More preferably, it is 70,000 or more and 200,000 or less. More preferably, it is 70,000 or more and 120,000 or less. The weight average molecular weight was determined by gel permeation chromatography (GPC) manufactured by JASCO Corporation (Pump: Gulliver, PU-1580; Column: Shodex (registered trademark) (KF-807, KF-806M, KF- 806M, KF-802.5) 4 in series; mobile phase solvent: tetrahydrofuran; using the standard curve of polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko Co., Ltd.) to obtain in polystyrene conversion.

The alkali-soluble resin is preferably a copolymer composed of at least one or more first monomers described later and at least one or more second monomers described below.

The first monomer is a carboxylic acid or acid anhydride having one polymerizable unsaturated group in the molecule. Examples thereof include (meth)acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, and maleic acid half esters. Among them, (meth)acrylic acid is particularly preferable.

Here, (meth)acrylic acid means acrylic acid and/or methacrylic acid. The following are the same.

The second monomer is a non-acidic monomer having at least one polymerizable unsaturated group in its molecule. Examples include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, (meth)acrylate ) isobutyl acrylate, tert-butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, ( Benzyl meth)acrylate, esters of vinyl alcohol such as vinyl acetate, (meth)acrylonitrile, styrene, and styrene derivatives. Among them, methyl (meth)acrylate, n-butyl (meth)acrylate, styrene, and benzyl (meth)acrylate are preferable.

(a) The alkali-soluble resin contains carboxyl groups, has an acid equivalent of 100 to 600, and has a weight average molecular weight of 70,000 to 220,000, which is a preferred embodiment of the present invention from the viewpoint of pore capping properties and properties of aggregates.

(a) The overall ratio of the alkali-soluble resin to the photosensitive resin composition is in the range of 25 to 64% by mass, preferably 40 to 60% by mass. The resist pattern formed by exposure and development is preferably 25% by mass or more and 64% by mass or less in view of resist characteristics such as sufficient resistance in capping, etching, and various plating processes.

(b) Photopolymerizable unsaturated compound

A photopolymerizable unsaturated compound means a compound having at least one ethylenically unsaturated bond in a molecule.

In the photosensitive resin composition of the present invention, as (b) a photopolymerizable unsaturated double bond compound, relative to the total amount of the photosensitive resin composition, 30 to 55 mass % of compounds selected from the following general formula At least one photopolymerizable unsaturated compound in the group consisting of the compound represented by (I) and the compound represented by the following general formula (II).

[chemical formula 5]

(In the formula, R ₁ , R ₂ , and R ₃ are each independently H or CH ₃ , and n ₁ , n ₂ , n ₃ , and n ₄ are each independently an integer of 0 to 4, and may be 0 at the same time. W is a group represented by CH ₃ or OH.)

[chemical formula 6]

(In the formula, R ₅ , R ₆ , R ₇ and R ₈ are each independently H or CH ₃ , m ₁ , m ₂ , m ₃ and m ₄ are each independently an integer of 0 to 4, and can also be 0 at the same time .)

Specific examples of at least one photopolymerizable unsaturated compound selected from the group consisting of compounds represented by the above general formula (I) and compounds represented by the above general formula (II) include, for example, those in the above general formula ( In I), R ₁ , R ₂ , and R ₃ are H, n ₁ , n ₂ , and n ₃ are an integer of 1, n ₄ is an integer of 0, and W is a compound of CH ₃ (New Nakamura Chemical Industry Co., Ltd. Manufactured NK ester A-TMPT-3PO); the same in the above general formula (I), R ₁ , R ₂ , and R ₃ are H, n ₁ , n ₂ , and n ₃ are integers of 3, n ₄ is an integer of 0, and W is a compound of CH ₃ (NK ester A-TMPT-9PO manufactured by Shin-Nakamura Chemical Co., Ltd.), etc. In addition, in the above-mentioned general formula (II), R ₅ , R ₆ , R ₇ , and R ₈ are H, and m ₁ , m ₂ , m ₃ , and m ₄ are compounds that are integers of 0 (Shin Nakamura Chemical Co., Ltd. NK ester A-TMMT manufactured by Kogyo Co., Ltd.), the same in the above general formula (II), R ₅ , R ₆ , R ₇ , and R ₈ are H, m ₁ , m ₂ , m ₃ , and m ₄ A compound that is an integer of 1 (SR-494 manufactured by Satoma Japan Co., Ltd.).

From the viewpoint of capping properties, the content of at least one photopolymerizable unsaturated compound selected from the group consisting of the compound represented by the above general formula (I) and the compound represented by the above general formula (II) is 35 to 50%. 55% by mass, more preferably 40 to 55% by mass. In addition, in (b) the photopolymerizable unsaturated compound, the photopolymerizable unsaturated compound shown below other than the compound represented by the said General formula (I) and the said General formula (II) can also be used. Examples include 1,6-hexanediol di(meth)acrylate, 1,4-cyclohexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2- Di(p-hydroxyphenyl)propane di(meth)acrylate, glycerol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, polyoxypropyl trimethylolpropane tri( Meth)acrylate, polyoxyethyltrimethylolpropane triacrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, trimethylolpropane triglycidyl ether tri(meth)acrylate base) acrylate, bisphenol A diglycidyl ether di(meth)acrylate, β-hydroxypropyl-β'-(acryloyloxy)propyl terephthalate, phenoxy polyethylene glycol Alcohol (meth)acrylate, Nonylphenoxy polyethylene glycol (meth)acrylate, Nonylphenoxy polyalkylene glycol (meth)acrylate, Polypropylene glycol mono(meth)acrylate .

In addition, urethane compounds are also mentioned. As the urethane compound, for example, hexamethylene diisocyanate, benzylidene diisocyanate, or a diisocyanate compound such as 2,2,4-trimethylhexamethylene diisocyanate, and one molecule having a hydroxyl group and (Meth)acrylic compounds such as 2-hydroxypropyl acrylate, and urethane compounds of oligopropylene glycol monomethacrylate. Specifically, there is a reaction product of hexamethylene diisocyanate and oligopropylene glycol monomethacrylate (Blenmer PP1000 manufactured by NOF Corporation). These may be used alone or in combination of two or more.

The total content of (b) photopolymerizable unsaturated double bond compounds including photopolymerizable unsaturated compounds is 30 to 55% by mass, preferably 35% to 55% by mass relative to the total amount of the photosensitive resin composition. %. More preferably 40 to 55% by mass, wherein the photopolymerizable unsaturated compound (b) is at least A photopolymerizable unsaturated compound.

In addition, when the proportion of the above-mentioned (a) alkali-soluble resin relative to the total amount of the photosensitive resin composition is A mass %, and the proportion of the above-mentioned (b) compound having a photopolymerizable unsaturated double bond is B mass %, A/B is 1.1 to 1.3, which is a preferred embodiment of the present invention. From the viewpoint of capping properties, A/B is preferably 1.1 or more, more preferably A/B 1.3 or less.

(c) Photopolymerization initiator

In a photosensitive resin composition, a known thing can be used normally as (c) photoinitiator. The quantity of (c) photoinitiator contained in a photosensitive resin composition is the range of 0.1-20 mass %, and a more preferable range is 0.5-10 mass %. From the viewpoint of obtaining sufficient sensitivity, it is preferably 0.1% by mass or more, and from the viewpoint of sufficiently transmitting light to the bottom surface of the resist and obtaining good resolution, it is preferably 20% by mass or less.

As such a photopolymerization initiator, there are 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzoanthraquinone, 2,3-benzoanthraquinone, 2-phenylanthraquinone, 2,3 -Diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone Quinone, 9,10-phenanthrenequinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone and other quinones; aromatic ketones, For example benzophenone, Michler's ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, benzoin or benzoin Ethers, such as benzoin, benzoin ethyl ether, benzoin phenyl ether, methylbenzoin, ethylbenzoin, dialkyl ketals, such as benzil dimethyl ketal, benzoin diethyl ketal; thioxanthones, such as diethylthioxanthone, chlorothioxanthone; dialkylaminobenzoic acid esters, such as ethyl dimethylaminobenzoate; oxime esters, such as 1-phenyl-1,2-propanedione-2-O-benzoyl oxime, 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime; Profen base ( Lophine) dimers, such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-bis-(m-methoxyphenyl ) imidazole dimer, 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; acridine compounds, eg 9-phenylacridine. These compounds may be used alone or in combination of two or more. From the viewpoint of improving pore-clogging properties and suppressing the generation of oily aggregates, acridine compounds are preferred, and 9-phenylacridine is particularly preferred. The so-called oily aggregates here are considered to mean highly viscous aggregates, and a compound having an unsaturated double bond is a main component. On the other hand, powdery aggregates are considered to be aggregates that contain a polymerization inhibitor and an initiator as main components, and are different from oily aggregates.

(d) Other ingredients

In order to improve the handleability of the photosensitive resin composition in this invention, you may add a leuco dye, or a fluoran dye, and a coloring substance.

Examples of leuco dyes include tris(4-dimethylaminophenyl)methane [leuco crystal violet] and bis(4-dimethylaminophenyl)phenylmethane [leuco malachite green]. Among them, when leuco crystal violet is used, the contrast is good, so it is preferable. It is preferable to contain 0.1-10 mass % of content in the case of containing a leuco dye in a photosensitive resin composition. From the viewpoint of expressing contrast, it is preferably 0.1% by mass or more, and from the viewpoint of maintaining storage stability, it is preferably 10% by mass or less.

In the photosensitive resin composition, it is a preferred embodiment of the present invention when a leuco dye and a halogen compound described below are used in combination from the viewpoint of adhesion and contrast.

Examples of coloring substances include basic fuchsin, phthalocyanine green, auramine base, paramagentin, crystal violet, methyl orange, Nile blue-2B, Victoria blue, and malachite green (manufactured by Hodo Ketani Chemical Co., Ltd. , Aizen (registered trademark) MALACHITEGREEN), basic blue 20, diamond green (made by Hodo Ketani Chemical Co., Ltd., Aizen (registered trademark) DIAMOND GREEN GH). When the coloring substance is contained, the amount added is preferably 0.001 to 1% by mass in the photosensitive resin composition. When the content is 0.001 mass % or more, it has the effect of improving workability, and when it is 1 mass % or less, it has the effect of maintaining storage stability.

The photosensitive resin composition of the present invention may contain an N-aryl-α-amino acid compound from the viewpoint of sensitivity. As the N-aryl-α-amino acid compound, N-phenylglycine is preferred. When the N-aryl-α-amino acid compound is contained, the content is preferably not less than 0.01% by mass and not more than 30% by mass.

In the photosensitive resin composition of this invention, you may contain a halogen compound. Examples of halogen compounds include pentane bromide, isopentyl bromide, isobutylene bromide, vinyl bromide, diphenylmethane bromide, benzylidene dibromide, methylene bromide, and tribromomethylphenyl sulfone. , carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, iodopentane, iodoisobutane, 1,1,1-trichloro-2,2-bis (p-chlorophenyl)ethane and halogenated triazine compounds, among which, tribromomethylphenyl sulfone is particularly preferably used. When containing a halogen compound, content is 0.01-3 mass % in a photosensitive resin composition.

Furthermore, in order to improve the thermal stability and storage stability of the photosensitive resin composition of the present invention, a free radical inhibitor, benzotriazoles, and carboxybenzotriazoles can be added to the photosensitive resin composition. At least one or more compounds in the group consisting of classes.

Examples of such radical inhibitors include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, ketone chloride, 2,6-di-tert-butyl - p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol) , nitrosophenylhydroxylamine aluminum salt, and diphenylnitrosamine.

In addition, examples of benzotriazoles include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, bis(N-2-ethylhexyl) Aminomethylene-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-benzotriazole, and bis(N-2-hydroxy Ethyl)aminomethylene-1,2,3-benzotriazole.

In addition, examples of carboxybenzotriazoles include 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, N-(N, N-di-2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, and N-(N , N-di-2-ethylhexyl)aminoethylenecarboxybenzotriazole.

The total addition amount of the radical polymerization inhibitor, benzotriazoles, and carboxybenzotriazoles is preferably 0.01 to 3% by mass, more preferably 0.05 to 1% by mass. From the viewpoint of imparting storage stability to the photosensitive resin composition, the amount is preferably 0.01% by mass or more, and more preferably 3% by mass or less from the viewpoint of maintaining sensitivity.

In the photosensitive resin composition of this invention, you may contain a plasticizer as needed. Such plasticizers include, for example, polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether , polyoxyethylene monoethyl ether, polyoxypropylene monoethyl ether, polyoxyethylene polyoxypropylene monoethyl ether and other glycols and esters, diethyl phthalate and other phthalates, o-toluenesulfonamide, p- Methylbenzenesulfonamide, tributyl citrate, triethyl citrate, acetyl triethyl citrate, acetyl tri-n-propyl citrate, acetyl tri-n-butyl citrate.

As content of a plasticizer, it is preferable to contain 5-50 mass % in a photosensitive resin composition, More preferably, it is 5-30 mass %. From the viewpoint of suppressing delay in development time and imparting flexibility to the cured film, it is preferably 5% by mass or more, and from the viewpoint of suppressing insufficient curing and cold flow, it is preferably 50% by mass or less.

The photosensitive resin laminated body of this invention contains the photosensitive resin layer which consists of a photosensitive resin composition, and a support layer. If necessary, a protective layer may be provided on the surface of the photosensitive resin layer opposite to the support layer side. As the support layer used here, it is desirable to be a transparent support layer which can transmit the light emitted from the exposure light source. Examples of such supports include polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethacrylic acid Methyl ester copolymer films, polystyrene films, polyacrylonitrile films, styrene copolymer films, polyamide films, and cellulose derivative films. For these films, stretched films can also be used as needed. Preferably, the turbidity is 5 or less. Regarding the thickness of the film, a thin film is advantageous in terms of image formation and economical efficiency, and since strength must be maintained, a thickness of 10 to 30 μm is preferably used.

In addition, as an important characteristic of the protective layer used in the photosensitive resin laminate, in terms of adhesion to the photosensitive resin layer, compared with the support layer, the protective layer is sufficiently small in adhesion and can be easily peeled off. . For example, a polyethylene film, a polypropylene film, etc. can be preferably used as a protective layer. In addition, a film excellent in peelability as disclosed in JP-A-59-202457 can be used. The film thickness of the protective layer is preferably 10 to 100 μm, more preferably 10 to 50 μm. Although the thickness of the photosensitive resin layer in a photosensitive resin laminated body changes with a use, Preferably it is 5-100 micrometers, More preferably, it is 7-60 micrometers. The thinner the thickness, the higher the resolution, and the thicker the thickness, the higher the film strength.

The method for producing the photosensitive resin laminate of the present invention by sequentially laminating the support layer, the photosensitive resin layer and, if necessary, the protective layer can be a conventionally known method. For example, the photosensitive resin composition used in the photosensitive resin layer is made into a uniform solution mixed with the solvent for dissolving them in advance, and it is first coated on the support layer using a rod coater or a roll coater, dried, and then coated on the support layer. A photosensitive resin layer composed of the photosensitive resin composition is laminated on the layer. Then, a photosensitive resin laminate can be produced by laminating a protective layer on the photosensitive resin layer as needed.

Examples of the solvent include ketones represented by methyl ethyl ketone (MEK), and alcohols represented by methanol, ethanol, and isopropanol. It is preferable to add to the photosensitive resin composition so that the solution viscosity of the photosensitive resin composition coated on the support layer may be 500-4000 mPa at 25 degreeC.

<Resist Pattern Formation Method>

The resist pattern using the photosensitive resin laminate of this invention can be formed by the process including a lamination process, an exposure process, and a development process. An example of a specific method is shown below.

As substrates to be processed, copper-clad laminates are used in the manufacture of printed wiring boards, and glass substrates used in the manufacture of uneven substrates include, for example, substrates for plasma display panels and substrates for surface electrolytic displays, Silicon wafers and ceramic substrates with through-holes for organic EL sealing covers. A substrate for a plasma display is a substrate in which electrodes are formed on glass, a dielectric layer is applied, a glass paste for barrier ribs is applied, and the glass paste for barrier ribs is sandblasted to form barrier ribs. The products obtained by blasting these processed substrates are concave-convex substrates.

First, a lamination process is performed using a laminator. When the photosensitive resin laminate has a protective layer, the protective layer is peeled off, and then, the photosensitive resin layer is thermally and pressure-bonded and laminated on the surface of the substrate using a laminator. At this time, the photosensitive resin layer may be laminated on only one surface of the substrate, or may be laminated on both surfaces as necessary. The heating temperature at this time is normally 40-160 degreeC. In addition, adhesive force and chemical resistance are improved by performing this thermocompression bonding two or more times. In this case, a two-stage laminator having two consecutive rollers may be used for the crimping, or the crimping may be performed by repeatedly passing the rollers multiple times.

Then, an exposure process is performed using an exposure machine. When necessary, the support is peeled off and exposed to active light through a photomask. The amount of exposure is determined by the illuminance of the light source and the exposure time. It can also be measured using a light meter.

In addition, in the exposure step, a direct drawing exposure method can also be used. Direct drawing exposure is a method of performing exposure by direct drawing on a substrate without using a photomask. As a light source, for example, a semiconductor laser with a wavelength of 350 to 410 nm, an ultra-high pressure mercury lamp, or the like is used. The drawing pattern is controlled by a computer, and the exposure amount in this case is determined by the illuminance of the light source and the moving speed of the substrate.

Next, a developing step is performed using a developing device. After exposure, when there is a support on the photosensitive resin layer, this support is removed. Next, the unexposed portion is developed and removed using an alkaline aqueous solution to obtain a resist image. As the alkaline aqueous solution, an aqueous solution of Na ₂ CO ₃ or K ₂ CO ₃ is preferably used. These can be appropriately selected according to the characteristics of the photosensitive resin layer, and are usually a Na ₂ CO ₃ aqueous solution at a concentration of 0.2 to 2% by mass and at 20 to 40°C. A surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, and the like may also be mixed into the alkaline aqueous solution.

The resist pattern is obtained through the above-mentioned steps, but a heating step of heating the resist pattern to 100 to 300° C. may also be performed depending on the situation. By performing this heating process, chemical resistance can be further improved. A heating furnace that can use hot air, infrared rays, or far infrared rays for heating.

<Manufacturing method of conductor pattern and manufacturing method of printed wiring board>

The method of manufacturing a printed wiring board of the present invention is carried out through the following steps following the above-mentioned resist pattern forming method using a copper-clad laminate or a flexible substrate as a substrate.

First, the copper surface of the substrate exposed by development is used to form a conductor pattern using a known method such as an etching method or a plating method.

Then, the resist pattern is peeled off from the substrate using an aqueous solution having a stronger alkalinity than the developer, thereby obtaining a desired printed wiring board. The alkaline aqueous solution for peeling (hereinafter also referred to as "stripping solution") is not particularly limited, but an aqueous solution of NaOH or KOH at a concentration of 2 to 5% by mass and at 40 to 70°C is usually used. A small amount of water-soluble solvent can also be added to the stripping solution.

<Manufacturing method of lead frame>

The lead frame manufacturing method of the present invention is carried out through the following steps following the above-mentioned resist pattern forming method using a metal plate such as copper, copper alloy, or iron-based alloy as a substrate.

First, the substrate exposed by development is etched to form a conductor pattern. Then, the resist pattern is peeled off by the same method as the method of manufacturing the above-mentioned printed wiring board to obtain a desired lead frame.

<Manufacturing method of semiconductor package>

The manufacturing method of the semiconductor package of the present invention is carried out through the following steps following the above-mentioned resist pattern forming method using the wafer on which the circuit formation as the LSI is completed as the substrate.

First, the opening exposed by development is subjected to columnar plating with copper or solder to form a conductor pattern. Then, the resist pattern is lifted off by the same method as the above-mentioned method of manufacturing the printed wiring board, and the thin metal layer is removed by etching to obtain a desired semiconductor package.

Example

The present invention will be described based on examples.

The preparation method of the sample for evaluation of an Example and a comparative example, and the evaluation method and evaluation result of the obtained sample are shown below.

1) Preparation of samples for evaluation

The photosensitive resin laminates in Examples and Comparative Examples were produced as follows.

<Production of photosensitive resin laminate>

The solution of the composition shown in Table 1 was prepared so that the solid content amounted to 50% by mass, and fully stirred and mixed, and was prepared on a 16 μm thick polyethylene terephthalate film (manufactured by Mitsubishi Chemical Corporation) as a support film. On R340-G16), the photosensitive resin composition shown in Table 1 was uniformly apply|coated using the mixing coater, and it dried at 95 degreeC for 1 minute. The film thickness of the photosensitive resin layer after drying was 10 micrometers. Next, on the surface on the photosensitive resin layer, a 35 μm thick polyethylene film (GF-858 manufactured by Tamapoli Co., Ltd.) was bonded as a protective layer to obtain a photosensitive resin laminate.

<substrate>

Evaluation was performed using a 0.4 mm thick copper clad laminate laminated with 35 μm copper foil on an insulating resin. In addition, the gist is described below when using other substrates.

<Laminated>

While peeling off the protective layer of the photosensitive resin laminate of the present invention, lamination was performed at a roll temperature of 105° C. using a hot roll laminator (manufactured by Asahi Kasei Engineering Co., Ltd., AL-700). The air pressure is 0.35MPa, and the lamination speed is 1.5m/min.

<exposure>

The photosensitive resin layer was exposed at an exposure amount of 12 mJ/cm ² at 8 W or less using a direct drawing exposure machine (made by Orbotec Co., Ltd., Paragon 9000).

<development>

A 1.0% by mass Na ₂ CO ₃ aqueous solution at 30° C. was sprayed for a predetermined time to dissolve and remove the unexposed portion of the photosensitive resin layer. The actual development time was 24 seconds for development, and then, the water washing time was 36 seconds for water washing.

2) Evaluation method

In addition to the method described above for preparing the evaluation sample, each performance was evaluated by the following method.

<Cover Pore>

For the substrate laminated on both sides of the copper-clad laminate by the above method, use the above-mentioned exposure method to perform full-surface direct tracing exposure and obtain a cured film. The copper-clad laminate is 0.2 mm thick and 2500 pieces are produced. A 500 mm x 500 mm copper-clad laminate with through-holes having a diameter of 0.3 mm was developed by the above-mentioned developing method. The number of cracks in the cured film was counted after development and graded as follows.

◎: The number of cracks is 25 or less

○: The number of cracks exceeds 25 and is 75 or less

×: The number of broken objects exceeds 75 pieces.

<Generation of oily aggregates>

Only the photosensitive resin layer of the photosensitive resin laminate was aggregated to 2.4 m ² , immersed in 200 ml of developer solution, stirred at 30° C. for 2 hours, and dissolved. Then, it was allowed to stand still, and the classification described below was carried out according to the state of the solution after 72 hours.

◯: Oily aggregates and powdery aggregates did not occur.

Δ: There are few oily aggregates and powdery aggregates.

×: There are many oily aggregates and powdery aggregates.

<Peel Strength of Support Layer (PET)>

Prepare the substrate on which the photosensitive resin layer of the photosensitive resin laminate is laminated on one side by the above-mentioned method, place it at 23° C. and 50% relative humidity for 24 hours, and then apply a 1-inch-wide support layer (here, PET ) was subjected to 180° peeling, and the strength was measured with Tensilon RTM-500 (manufactured by Toyo Seiki Co., Ltd.), and classified as follows.

◯: The maximum average value of the peel strength is 3 gf or more.

Δ: The maximum average value of the peel strength is less than 3 gf.

3) Evaluation results

Table 1 shows the evaluation results of Examples and Comparative Examples. The parts by mass of B-1 to B-4 in Table 1 are parts by mass of solid content and do not contain a solvent. In order to prepare a photosensitive resin composition, the solid content density|concentration of B-1-B-4 was previously prepared the methyl ethyl ketone solution of 50 mass %, and each solution of B-1-B-4 was mixed so that the solid content of Table 1 might be obtained.

[Table 1]

<Description of symbols>

B-1: Terpolymer of 25% by mass of methacrylic acid, 65% by mass of methyl methacrylate, and 10% by mass of butyl acrylate (weight average molecular weight: 100,000, acid equivalent: 344)

B-2: Terpolymer of 25% by mass of methacrylic acid, 65% by mass of methyl methacrylate, and 10% by mass of butyl acrylate (weight average molecular weight: 200,000, acid equivalent: 370)

B-3: Terpolymer of 25% by mass of methacrylic acid, 50% by mass of methyl methacrylate, and 25% by mass of styrene (weight average molecular weight: 50,000, acid equivalent: 344)

B-4: Terpolymer of 25% by mass of methacrylic acid, 50% by mass of methyl methacrylate, and 25% by mass of butyl acrylate (weight average molecular weight: 70,000, acid equivalent: 344)

B-5: binary copolymer of 80% by mass of benzyl methacrylate and 20% by mass of methacrylic acid (weight average molecular weight: 100,000, acid equivalent: 430)

M-1: Tetraacrylate in which 1 mole of ethylene oxide was added to each of the four ends of pentaerythritol (SR-494 manufactured by Satoma Japan Co., Ltd.)

M-2: Tetraacrylate in which 4 terminals of pentaerythritol are acrylated

M-3: Triacrylate (A-TMPT-3EO made by Shin-Nakamura Chemical Co., Ltd.) which added 3 moles of ethylene oxide to trimethylolpropane on average

M-4: triacrylate with an average of 3 moles of propylene oxide added to trimethylolpropane

M-5: Dimethacrylate of polyethylene glycol to which 2 moles of ethylene oxide are added on average to both ends of bisphenol A

M-6: Polypropylene glycol diacrylate

I-1: 9-phenylacridine

I-2: N-Phenylglycine

I-3: 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer

I-4: 1-phenyl-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline

I-5: 2-(o-chlorophenyl)-4,5-bis(m-methoxyphenyl)imidazole dimer

D-1: Diamond Green

D-2: Crystal Violet

F-1: methyl ethyl ketone

In Comparative Example 1, when a polymer having an average molecular weight of less than 70,000 was used as the alkali-soluble resin, oily aggregates were generated at the time of image development, causing problems.

In Comparative Example 2, the ratio of the compound represented by the above general formula (II) in the photosensitive resin composition was less than 30% by mass, which resulted in deterioration of pore-clogging properties.

In Comparative Example 3, the ratio of the compound represented by the above-mentioned general formula (II) in the photosensitive resin composition was greater than 55% by mass, and the ratio of the above-mentioned (a) alkali-soluble resin was set to the total amount of the photosensitive resin composition When it is A mass %, and the ratio of the said (b) photopolymerizable compound which has an unsaturated double bond is B mass %, A/B will be less than 1.1, and will result in deterioration of capping property. Comparative Example 4 is an additional experiment of JP 11-119422. In Comparative Example 4, a polyfunctional photopolymerizable unsaturated compound corresponding to the compound represented by the above-mentioned general formula (I) and the compound represented by the above-mentioned general formula (II) was not used, so the capping property deteriorated, and it became an oily product. result of aggregates.

Industrial availability

The photosensitive resin laminate of the present invention protects the through holes from the influence of alkaline developer and etching solution by exposing on the laminated substrate, thereby simplifying the follow-up process. There is less aggregation, so there is less cleaning of the device, and in addition, it is useful in the production of printed wiring boards by alkali development.

Claims (11)

1. A photosensitive resin laminate, characterized in that it is a photosensitive resin laminate formed by laminating at least a support layer and a photosensitive resin layer, the photosensitive resin layer being formed from a photosensitive resin composition, The photosensitive resin composition comprises at least: (a) Alkali-soluble resin 25-64 mass %, (b) photopolymerizable compounds having unsaturated double bonds, (c) 0.1-20% by mass of photopolymerization initiator, And further satisfy the following (i), (ii), (iii) and (iv): (i) As the (b) photopolymerizable compound having an unsaturated double bond, it contains 30 to 55% by mass of a compound selected from the group represented by the following general formula (I) with respect to the total amount of the photosensitive resin composition. At least one photopolymerizable unsaturated compound in the group consisting of a compound and a compound represented by the following general formula (II); (ii) the weight-average molecular weight of the (a) alkali-soluble resin is 70,000-220,000, and the acid equivalent is 100-600; (iii) the thickness of the photosensitive resin layer is 3-15 μm, (iv) When the proportion of the above-mentioned (a) alkali-soluble resin relative to the total amount of the photosensitive resin composition is A mass %, and the proportion of the above-mentioned (b) photopolymerizable compound having an unsaturated double bond is B mass % , A/B is 1.1～1.31, [chemical formula 1] In the formula, R ₁ , R ₂ and R ₃ are each independently H or CH ₃ , n ₁ , n ₂ , n ₃ and n ₄ are each independently an integer from 0 to 4, and can also be 0 at the same time, and W is in the range A group represented by CH ₃ or OH, [chemical formula 2] In the formula, R ₅ , R ₆ , R ₇ and R ₈ are each independently H or CH ₃ , m ₁ , m ₂ , m ₃ and m ₄ are each independently an integer of 0 to 4, and may be 0 at the same time. 2. The photosensitive resin laminate according to claim 1, wherein, as the (b) photopolymerizable compound having an unsaturated double bond, 35 to 55% by mass of at least one photopolymerizable unsaturated compound selected from the group consisting of the compound represented by the general formula (I) and the compound represented by the general formula (II). 3. The photosensitive resin laminate according to claim 1 or 2, wherein (c) the photopolymerization initiator is 9-phenylacridine. 4. The photosensitive resin laminate according to claim 1 or 2, wherein A/B in (iv) is 1.1 to 1.3. 5. A method for forming a resist pattern, comprising a lamination step of laminating the photosensitive resin layer of the photosensitive resin laminate according to any one of claims 1 to 4 on a substrate, and an exposure step of exposing ultraviolet rays , Remove the unexposed part of the development process. 6. The method for forming a resist pattern according to claim 5, wherein the exposure is performed by direct drawing in the exposure step. 7. A method for manufacturing a conductive pattern, comprising: using a copper-clad laminate as a substrate, etching or plating the substrate on which the resist pattern is formed by the method according to claim 5 or 6. 8. A method for manufacturing a printed wiring board, characterized in that, using a metal-clad insulating board as a substrate, etching or plating the substrate with the resist pattern formed by the method according to claim 5 or 6, peeling off the resist Eclipse pattern. 9 . A method for manufacturing a lead frame, wherein a metal plate is used as a substrate, and the substrate on which the resist pattern is formed by the method according to claim 5 or 6 is etched to peel off the resist pattern. 10. A method for manufacturing a semiconductor package, characterized in that, using a wafer on which a circuit of a large-scale integrated circuit has been formed is used as a substrate, and the substrate formed with a resist pattern by the method according to claim 5 or 6 is plated Apply and strip the resist pattern. 11. A method for manufacturing a substrate with a concave-convex pattern, characterized in that, using glass ribs as the substrate, using a sandblasting process to process the substrate with the resist pattern formed by the method according to claim 5 or 6, and peeling off resist pattern.