JP6810024B2 - Positive photosensitive resin composition, dry film, cured product and printed wiring board - Google Patents

Description

The present invention relates to positive photosensitive resin compositions, dry films, cured products and printed wiring boards.

Polyimide is widely applied in various fields based on its excellent properties such as high insulation, heat resistance, and high mechanical strength. For example, it is being applied not only to the aerospace field where it was first applied, but also to coating films for semiconductor devices, flexible printed wiring boards, and heat-resistant insulating interlayer materials.

Polyimide has an aspect that it is difficult to process due to its poor thermoplasticity and solubility in an organic solvent. For this reason, polyimide forms a desired pattern film by developing a photosensitive resin composition obtained by blending a polyamic acid with a photoreactive compound after irradiating it with active light rays, and then applies a high temperature to close the ring. It is widely used by the method of imidizing.

For example, Patent Document 1 describes a positive photosensitive resin composition containing a polyamine acid condensate of an aromatic dianhydride and an aromatic diamine and a quinonediazide compound. Further, Patent Document 2 describes a positive photosensitive resin composition containing a poly (amide-imide) resin having a specific structure and a photoacid generator.

Japanese Unexamined Patent Publication No. 52-13315 Japanese Unexamined Patent Publication No. 2010-196041

In recent years, with the advancement of semiconductor mounting technology and the increase in density, further miniaturization of pattern films has been required. However, with the above-mentioned photosensitive resin composition, it has been difficult to obtain a high degree of resolution.

Therefore, an object of the present invention is a positive photosensitive resin composition having excellent resolution, a dry film having a resin layer obtained from the composition, a cured product of the composition or the resin layer of the dry film, and the like. An object of the present invention is to provide a printed wiring board having the cured product.

As a result of diligent studies in view of the above, the present inventors have changed from an acid anhydride having an aromatic skeleton and a polyamic acid obtained from a diamine to an acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton, and a diamine. It has been found that a cured product having surprisingly excellent resolution can be obtained by using the obtained polyaromatic acid.
Further, the present inventors have obtained a cured product having better resolution by using a polyamic acid that is substantially imidized than a poly (amide-imide) resin in which a part of the polyamic acid is imidized. I found that I could get it.

Therefore, the present invention is characterized by containing (A) an acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton, a polyamic acid obtained from a diamine, and (B) a photoacid generator. It is a positive photosensitive resin composition.

In the positive photosensitive resin composition of the present invention, the polyamic acid (A) is based on the following general formula (I):
(In the formula, R ₁ is a tetravalent organic group containing a fused ring of an aromatic ring and an aliphatic hydrocarbon ring, or a tetravalent organic group containing an aromatic group and an alicyclic hydrocarbon group. ,
R ₂ is a divalent organic group
X is a divalent organic group,
m is an integer of 1 or more, and n is an integer of 0 or 1 or more. )
It is preferable that the compound has a structure represented by.

In the positive photosensitive resin composition of the present invention, the polyamic acid (A) is based on the following general formula (II):
(In the formula, R ₂ is a divalent organic group, X is a divalent organic group, m is an integer of 1 or more, and n is an integer of 0 or 1 or more.)
It is preferable that the compound has a structure represented by.

In the positive photosensitive resin composition of the present invention, the polyamic acid (A) is based on the following general formula (III):
(In the formula, R ₁ is a tetravalent organic group containing a fused ring of an aromatic ring and an aliphatic hydrocarbon ring, or a tetravalent organic group containing an aromatic group and an alicyclic hydrocarbon group. ,
R _{2, R 4} and _{R 6} is a divalent organic radical,
R ₃ and R ₅ are tetravalent organic groups and are
m is an integer of 1 or more, n and s are independently integers of 0 or 1 or more, and at least one of n and s is an integer of 1 or more. )
It is preferable that the compound has a structure represented by.

In the positive photosensitive resin composition of the present invention, the polyamic acid (A) is based on the following general formula (V):
(In the formula, R ₂ , R ₄ and R ₆ are divalent organic groups.
R ₃ and R ₅ are tetravalent organic groups and are
m is an integer of 1 or more, n and s are independently integers of 0 or 1 or more, and at least one of n and s is an integer of 1 or more. )
It is preferable that the compound has a structure represented by.

In the positive photosensitive resin composition of the present invention, the blending amount of the (B) photoacid generator is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the (A) polyamic acid.

The positive photosensitive resin composition of the present invention is developed by an exposure step of exposing a coating film of the positive photosensitive resin composition, a heating step of heating the coating film after the exposure step, and a heating step of heating the coating film. It is preferably used in a developing step and a method for forming a pattern film including.

The dry film of the present invention is characterized by having a resin layer obtained by applying the positive photosensitive resin composition to the film and drying it.

The cured product of the present invention is characterized by being obtained by curing the resin layer of the positive photosensitive resin composition or the dry film.

The printed wiring board of the present invention is characterized by having the cured product.

According to the present invention, a positive photosensitive resin composition having excellent resolution, a dry film having a resin layer obtained from the composition, a cured product of the composition or the resin layer of the dry film, and the same. A printed wiring board having a cured product can be provided.

Observation of (A) L / S = 3/3 μm, (B) 7/7 μm, and (C) 9/9 μm positive pattern films obtained using the positive photosensitive resin composition of Example 8 with a microscope. It is a photograph figure.

The positive photosensitive resin composition of the present invention contains (A) an acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton, a polyamic acid obtained from a diamine, and (B) a photoacid generator. It is characterized by.
In the present invention, as the acid anhydride as a raw material of the polyamic acid, an acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton is used, so that a cured product having excellent resolution can be obtained. For example, a pattern film having an L / S of 10/10 μm or less can be obtained.
In addition, the positive photosensitive resin composition of the present invention exhibits particularly excellent resolution when heated after light irradiation and before development. That is, by irradiating the coating film of the positive photosensitive resin composition of the present invention with active light rays, the solubility of the irradiated portion is increased, and a difference in solubility is generated between the irradiated portion and the non-irradiated portion. .. Then, by heating, imidizing a part of the polyamic acid in the unexposed portion and then developing it, a positive pattern film having excellent resolvability can be formed. After development, it may be heated at a higher temperature to completely imidize.

Hereinafter, the components contained in the positive photosensitive resin composition of the present invention will be described in detail.

[(A) Acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton, and a polyamic acid obtained from a diamine]
The acid anhydride having the (A) cyclic aliphatic skeleton and the aromatic skeleton used in the present invention and the polyamic acid obtained from the diamine (hereinafter, also referred to as “(A) polyamic acid”) are substantially imides. It has not been converted. The polyamic acid (A) preferably has a structure represented by the following general formula (I).

(In the formula, R ₁ is a tetravalent organic group containing a fused ring of an aromatic ring and an aliphatic hydrocarbon ring, or a tetravalent organic group containing an aromatic group and an alicyclic hydrocarbon group. ,
R ₂ is a divalent organic group
X is a divalent organic group,
m is an integer of 1 or more, and n is an integer of 0 or 1 or more. )

The polyamic acid (A) is obtained only from an acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton and a diamine, that is, n may be 0 in the general formula (I).

As a tetravalent organic group containing a fused ring of an aromatic ring of R ₁ and an aliphatic hydrocarbon ring,
It is preferably represented by any one of them.

Equation (1-1):
Z ₁ is an unsaturated hydrocarbon group having 4 to 12 carbon atoms that forms an aromatic ring (preferably a benzene ring, a naphthalene ring, particularly a benzene ring) together with an ethylene group common to Z _2, and is an aromatic ring. Uses at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), an aryl group (6 to 10 carbon atoms), a hydroxy group, and a halogen atom as substituents. You may have.

Z ₂ is an aliphatic hydrocarbon having 3 to 10 carbon atoms (preferably 4 to 6, particularly 4) forming an aliphatic hydrocarbon ring (aliphatic hydrocarbon) together with an ethylene group common to Z _1. It is a hydrogen group, and the aliphatic hydrocarbon ring has at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), and an aryl group (6 to 4 carbon atoms) as substituents. It may have 10), a hydroxy group, and a halogen atom. The two monovalent bonds represented by "-" (that is, a set of bonds, the bond on the right side of Z ₂ ) are bonded to adjacent carbons, but "= CR ₆ " The divalent bond represented by "-" is preferably bonded to the carbon atom next to the adjacent carbon atom to which the two "-" bonds are bonded or the carbon atom next to the bond. The latter is particularly preferable. For example, when the aliphatic hydrocarbon ring is a cyclohexane ring, two "-" bonds are bonded to the 3rd and 4th positions, and "= CR _6- " is placed at the 2nd or 1st position (preferably at the 1st position). It is preferable that they are bonded. R ₆ is generally a hydrogen atom, an alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), a hydroxy group, or a halogen atom, and a hydrogen atom is preferable.

Equation (1-2):
Z ₃ is an unsaturated hydrocarbon group having 4 to 12 carbon atoms that forms an aromatic ring (preferably a benzene ring, a naphthalene ring, particularly a benzene ring) together with an ethylene group common to Z _4, and is an aromatic ring. Uses at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), an aryl group (6 to 10 carbon atoms), a hydroxy group, and a halogen atom as substituents. You may have.

Z ₄ is an aliphatic hydrocarbon having 3 to 10 carbon atoms (preferably 4 to 6, particularly 4) forming an aliphatic hydrocarbon ring (aliphatic hydrocarbon) together with an ethylene group common to Z _3. It is a hydrogen group, and the aliphatic hydrocarbon ring has at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), and an aryl group (6 to 4 carbon atoms) as substituents. It may have 10), a hydroxy group, and a halogen atom. Two "-" monovalent bond represented by (a pair of bond, the right set of bond or left set of bonds of Z ₄₎ is attached to the carbon adjacent respectively However, a set of bonds may be arranged adjacent to each other, or if the ring is large, at least one carbon atom may be arranged with each other.

Equation (1-3):
Z ₅ is an unsaturated hydrocarbon group having 4 to 12 carbon atoms forming an aromatic ring (preferably a benzene ring, a naphthalene ring, particularly a benzene ring) together with an ethylene group common to Z _6, and is an aromatic ring. Uses at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), an aryl group (6 to 10 carbon atoms), a hydroxy group, and a halogen atom as substituents. You may have. The two monovalent bonds represented by "-" are bonded to adjacent carbons, but the combinations of adjacent monovalent bonds represented by two "-" are also adjacent to each other. If the ring is large, it may be arranged with at least one carbon atom placed on each other. Two "-" monovalent bond represented by is bonded to adjacent carbon "= CR 7 _-" divalent bonding hand represented by the "-" bonds of It is preferable that at least one carbon atom of the carbon to be bonded is placed and bonded to the adjacent carbon atom. R ₇ is generally a hydrogen atom, an alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), a hydroxy group, or a halogen atom, and a hydrogen atom is preferable.

Z ₆ is a fat having 3 to 10 carbon atoms (preferably 4 to 6, particularly 4) forming an aliphatic hydrocarbon ring (ring of an alicyclic hydrocarbon) together with an ethylene group common to Z _5. It is a group hydrocarbon group, and the saturated hydrocarbon ring has at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), and an aryl group (6 carbon atoms) as substituents. It may have 10), a hydroxy group, and a halogen atom.

Equation (1-4):
Z ₇ is an unsaturated hydrocarbon group having 4 to 12 carbon atoms forming an aromatic ring (preferably a benzene ring, a naphthalene ring, particularly a benzene ring) together with an ethylene group common to Z _8, and is an aromatic ring. Uses at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), an aryl group (6 to 10 carbon atoms), a hydroxy group, and a halogen atom as substituents. You may have. Two "-" monovalent bond represented by (right bond Z ₇ or the left bond of Z ₇₎ is bonded to the carbon adjacent each pair of The bonds may be arranged adjacent to each other, or if the ring is large, at least one carbon atom may be arranged with each other.

Z ₈ is saturated with 3 to 10 carbon atoms (preferably 4 to 6, particularly 4) forming an aliphatic hydrocarbon ring (alicyclic hydrocarbon ring) together with an ethylene group common to Z _7. It is a hydrocarbon group, and the saturated hydrocarbon ring has at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), and an aryl group (6 to 4 carbon atoms) as substituents. It may have 10), a hydroxy group, and a halogen atom.

Of the formulas (1-1) to (1-4), the organic group represented by the formulas (1-1) and (1-2) is preferable, and the organic group represented by the formula (1-1) is particularly preferable. preferable.

As a tetravalent organic group containing an aromatic group of R ₁ and an alicyclic hydrocarbon group,
It is preferably represented by.

A ¹ is a divalent aromatic ring (preferably a benzene ring, a naphthalene ring, particularly a benzene ring) or AR-R _10- AR [however, AR is a substituent {preferably at least one alkyl group (carbon atom). A divalent benzene ring (which may have 1 to 4 carbon atoms), an aryl group (6 to 10 carbon atoms), an alkoxy group (1 to 4 carbon atoms), a hydroxy group, a halogen atom}. preferably _{unsubstituted), R 10} is an alkylene group (preferably having from 1 to 4 carbon _{atoms), - SO 2 -, -} COO -, - it is CONH, -SO ₂ - are preferred. ].

R ₈ and R ₉ are independently single bonds, alkylene groups (1 to 4 carbon atoms), -SO _2- , -COO-, and -CONH-, and single bonds and -CONH- are preferable. ..

B ¹ and B ² are independently alicyclic hydrocarbon groups (cyclic aliphatic hydrocarbon groups) having 5 to 12 carbon atoms (preferably 6 to 8, particularly 6) and are saturated. The hydrocarbon ring has at least one alkyl group (1 to 4 carbon atoms), an alkoxy group (1 to 4 carbon atoms), an aryl group (6 to 10 carbon atoms), a hydroxy group, as substituents. It may have a halogen atom.

In formula (I), as described above, X is a divalent organic group, for example, an amic acid group, a hydroxyamic acid group, an aromatic or aliphatic ester group, an amide group, an amidimide group, a siloxane group, Examples thereof include groups containing at least a part of an epoxy group, an oxetanyl group and the like.

As described above, m is an integer of 1 or more. The preferable number average molecular weight of the polyamic acid (A) is 10 to 1,000,000, more preferably 5000 to 500,000, and further preferably 10,000 to 200,000. Therefore, m is set so as to satisfy this. Is preferable.

The compound having the structure represented by the general formula (I) is described in the following general formula (II):
It is particularly preferable that the compound is represented by. R _2, X, m, n are as described in Formula (I).

Further, as the compound having a structure represented by the general formula (I), a compound having a structure represented by the following general formula (III) can also be preferably used. By using a polyamic acid having an n of 1 or more in the general formula (I), for example, a polyamic acid having a copolymerization structure represented by the general formula (III), it is possible to improve the glass transition temperature (Tg) of the cured product. Become. That is, according to the positive photosensitive resin composition containing a polyamic acid having a copolymerization structure, it is possible to obtain a cured product having excellent heat resistance as well as resolution.

(In the formula, R ₁ is a tetravalent organic group containing a fused ring of an aromatic ring and an aliphatic hydrocarbon ring, or a tetravalent organic group containing an aromatic group and an alicyclic hydrocarbon group. ,
R _{2, R 4} and _{R 6} is a divalent organic radical,
R ₃ and R ₅ are tetravalent organic groups and are
m is an integer of 1 or more, n and s are independently integers of 0 or 1 or more, and at least one of n and s is an integer of 1 or more. )

R ₁ and R ₂ in the general formula (III) are as described in the formula (I).

As described above, R ₃ and R ₅ in the general formula (III) are tetravalent organic groups, for example, a group having a substituted or unsubstituted aromatic skeleton, or a substituted or unsubstituted cyclic fat. It is a group having a group skeleton, preferably a group having a substituted or unsubstituted aromatic skeleton, and more preferably a group having a benzene skeleton, a group having a biphenyl skeleton, or a group having a bisphenyl skeleton.
Here, the bisphenyl skeletons, for _{example, -O -, - CH 2 -} , - C 2 H 4 -, - C (CH 3) 2 -, - C (CF 3) 2 -, - SO 2 -, Examples thereof include a bisphenyl skeleton linked by −SO−, −S− or −CO−.

R ₄ and R ₆ in the general formula (III) are divalent organic groups as described above, and are the same as R ₂ in the general formula (I).

The sum of n and s is, for example, m: (n + s) = 1: 0 to 10, preferably m: (n + s) = 1: 0.1 to 5, with respect to m, more preferably. , M: (n + s) = 1: 0.3 to 3.

The compound in which s is 0 in the general formula (III) can be represented by the following general formula (IV).

R _{1 to} R ₄ , m and n are as described in the formula (III).

It is preferable that each compound having a structure represented by the general formula (III) has a structure represented by the following general formula (V).

_{R 2 ~R 6, m, n} , s are as described in formula (III).

The compound in which s is 0 in the general formula (V) can be represented by the following general formula (VI).

R ₂ ~R _4, m, n are as described in formula (III).

Further, when a pattern film is formed by short wavelength light, R _{1 to} R ₆ may each contain an aliphatic group from the viewpoint of the absorption characteristics of the polymer. Further, for example, when R _{1 to} R ₆ contain a group containing fluorine, the wavelength of light absorption can be lowered or the dielectric property can be improved.

As a result, the alkali developability becomes good, and a good pattern film can be obtained.

The acid value of the polyamic acid (A) is preferably 100 mgKOH / g or more, more preferably 150 mgKOH / g or more, and even more preferably 200 mgKOH / g or more. The upper limit of the acid value is preferably 300 mgKOH / g or less.
The acid value of (A) polyamic acid was measured according to JIS K-5601-2-1. As the diluting solvent for the sample, a mixed solvent of acetone / water (9/1 volume ratio) having an acid value of 0 is used so that the acid value of the anhydrous acid can also be measured.

The method for synthesizing the polyamic acid (A) is not particularly limited, and can be prepared by a conventionally known method. For example, an acid dianhydride having a cyclic aliphatic skeleton and an aromatic skeleton and a diamine can be synthesized simply by mixing them in a solution. Such a synthesis method is preferable because it can be synthesized by a one-step reaction, can be obtained easily and at low cost, and no further modification is required. By using at least one of acid anhydride and diamine in combination of two or more, a compound having a structure represented by the above general formula (III) can be easily produced as a copolymer.

The acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton used for obtaining the polyamic acid (A) is preferably a carboxylic acid dianhydride, and more preferably a tetracarboxylic dianhydride. preferable. As an example, the one represented by the following general formula (8) can be mentioned.

(R ₁ in the equation is as described in the equation (I).)

By using an acid anhydride of the general formula (8) as a starting material for the synthesis of (A) a polyamic acid, the R ₁ group in the repeating unit in the polyamic acid of the general formula (I) can be easily introduced.

The cyclohexane skeleton is preferable as the cyclic aliphatic skeleton of the acid anhydride. The acid anhydride preferably has no alkyl group (eg, t-butyl group) on the aromatic skeleton.

The acid anhydride preferably has an acid anhydride group having a succinic anhydride structure. Examples of the acid anhydride group having a succinic anhydride structure include the following acid anhydride groups.

Among the acid anhydrides, the following compounds are preferable.

The molecular weight of the acid anhydride is preferably 600 or less, more preferably 500 or less, and even more preferably 400 or less. The lower limit of the molecular weight is preferably 250 or more.

In the synthesis of (A) polyamic acid, other known acid dianhydrides can be used in combination as long as it does not contradict the gist of the present invention.

Examples of such other acid dianhydrides include ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, cyclobutanetetracarboxylic dianhydride, methylcyclobutanetetracarboxylic dianhydride, and cyclopentanetetra. Aliphatic tetracarboxylic dianhydrides such as carboxylic acid dianhydrides; pyromellitic dianhydrides, 3,3', 4,4'-benzophenonetetracarboxylic dianhydrides, 2,2', 3,3'. -Benzophenonetetracarboxylic dianhydride, 2,3', 3,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,2', 3,3'-biphenyltetracarboxylic dianhydride, 2,3', 3,4'-biphenyltetracarboxylic dianhydride, 2,2', 6,6'-biphenyltetracarboxylic dianhydride, 2 , 2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride Things, bis (3,4-dicarboxyphenyl) sulfonate dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride , Bis (3,4-dicarboxyphenyl) methanedianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropanedianhydride, 2,2-bis (2,3-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropanedianhydride, 1,3-bis [(3,4-dicarboxy) benzoyl] Benzylene dianhydride, 1,4-bis [(3,4-dicarboxy) benzoyl] benzene dianhydride, 2,2-bis {4- [4- (1,2-dicarboxy) phenoxy] phenyl} propane Dihydride, 2,2-bis {4- [3- (1,2-dicarboxy) phenoxy] phenyl} propane dianhydride, bis {4- [4- (1,2-dicarboxy) phenoxy] phenyl } Ketone dianhydride, bis {4- [3- (1,2-dicarboxy) phenoxy] phenyl} Ketene dianhydride, 4,4'-bis [4- (1,2-dicarboxy) phenoxy] biphenyl Dihydride, 4,4'-bis [3- (1,2-dicarboxy) phenoxy] biphenyl dianhydride, bis {4- [4- (1,2-dicarboxy) phenoxy] phenyl} ketone dianhydride Thing, screw {4- [3- (1,2-dicarboxy) phenoxy] phenyl} ketone dianhydride, bis {4- [4- (1,2-dicarboxy) phenoxy] phenyl} sulfone dianhydride, bis {4- [3 − (1,2-dicarboxy) phenoxy] phenyl} sulfone dianhydride, bis {4- [4- (1,2-dicarboxy) phenoxy] phenyl} sulfide dianhydride, bis {4- [3- ( 1,2-dicarboxy) phenoxy] phenyl} sulfide dianhydride, 2,2-bis {4- [4- (1,2-dicarboxy) phenoxy] phenyl} -1,1,1,3,3 3-Hexafluoropropane dianhydride, 2,2-bis {4- [3- (1,2-dicarboxy) phenoxy] phenyl} -1,1,1,3,3,3-hexafluoropropane dianhydride 2,3,6,7-naphthalenetetracarboxylic hydride, 1,1,1,3,3,3-hexafluoro-2,2-bis (2,3- or 3,4-dicarboxy) Phenyl) Propane dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, 1,2,3,4-benzenetetracarboxylic Acid dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic hydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride Anhydride, pyridinetetracarboxylic dianhydride, sulfonyldiphthalic anhydride, m-terphenyl-3,3', 4,4'-tetracarboxylic hydride, p-terphenyl-3,3', Aromatic tetracarboxylic dianhydrides such as 4,4'-tetracarboxylic hydrides and the like can be mentioned.

Examples of the diamine used to obtain the (A) polyamic acid include diamines represented by the following general formula (10). However, the following is an example, and known ones can be used as long as it does not contradict the gist of the present invention.

(In the formula, R ₂ is as described in the formula (I).)

The diamine preferably has an aromatic ring, and more preferably has a plurality of aromatic rings. When a plurality of aromatic rings are provided, it is preferable that the aromatic rings are directly bonded to each other or bonded via a (thio) ether group.

Examples of diamines when R ₂ is a divalent aromatic group include paraphenylenediamine, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-. Diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 9,10-bis (4-aminophenyl) anthracene, 4,4' -Diaminobenzophenone, 4,4'-diaminodiphenylsulphon, 3,3'-diaminodiphenylsulphon, 4,4'-diaminodiphenylsulfoxide, 1,3-bis (3-aminophenoxy) benzene, bis [4- (4-Aminophenoxy) phenyl] sulphon, bis [4- (3-aminophenoxy) phenyl] sulphon, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'-bis (3-aminophenoxybiphenyl) , Bis [4- (4-aminophenoxy) phenyl] ether, 1,1,1,3,3,3-hexafluoro-2,2-bis (4-aminophenyl) propane, 1,1,1,3 , 3,3-Hexafluoro-2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3-amino) -4-Methylphenyl) propane, metaphenylenediamine, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl ether, 1,4-bis Examples thereof include (4-aminophenoxy) benzene and 1,3-bis (4-aminophenoxy) benzene.

Examples of diamines when R ₂ is a divalent aliphatic group include 1,1-methaxylylene diamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, and heptamethylenediamine. , Octamethylenediamine, Nonamethylenediamine, 4,4-diaminoheptamethylenediamine, 1,4-diaminocyclohexane, Isophoronediamine, Tetrahydrodicyclopentadienirangeamine, Hexahydro-4,7-methanoin danirenenedimethylenediamine Examples thereof include tricyclo [6.2.1.02,7] -undecylenedimethyldiamine, 4,4'-methylenebis (cyclohexylamine), and isophoronediamine.

Further, as another example, a diaminopolysiloxane represented by the following formula (11) can be mentioned.

In the formula, R ₂₈ and R ₂₉ each independently represent a divalent hydrocarbon group, and R ₃₀ and R ₃₁ each independently represent a monovalent hydrocarbon group. p is an integer of 1 or more, preferably 1 to 10.

Specifically, R ₂₈ and R ₂₉ in the above formula (11) are alkylene groups having 1 to 7 carbon atoms such as a methylene group, ethylene group and propylene group, and arylene groups having 6 to 18 carbon atoms such as a phenylene group. Examples of R ₃₀ and R ₃₁ include an alkyl group having 1 to 7 carbon atoms such as a methyl group and an ethyl group, and an aryl group having 6 to 12 carbon atoms such as a phenyl group.

The diamine is particularly preferably a diaminodiphenyl ether such as 3,4'-diaminodiphenyl ether or 4,4'-diaminodiphenyl ether.

In the photosensitive resin composition, as the (A) polyamic acid, a single type of material may be used, or a plurality of types may be used as a mixture. Further, R ₁ and R ₂ may be copolymers having a plurality of structures, respectively.

The blending amount of the polyamic acid (A) is preferably 20 to 80% by mass based on the solid content of the composition.

[(B) Photoacid generator]
Examples of the photoacid generator include naphthoquinone diazide compounds, diarylsulfonium salts, triarylsulfonium salts, dialkylphenacylsulfonium salts, diaryliodonium salts, aryldiazonium salts, aromatic tetracarboxylic acid esters, and aromatic sulfonic acid esters. Examples thereof include nitrobenzyl ester, aromatic N-oxyimide sulfonate, aromatic sulfamide, benzoquinone diazosulfonic acid ester and the like. The photoacid generator (B) is preferably a dissolution inhibitor. Of these, it is preferably a naphthoquinone diazide compound.

Specific examples of the naphthoquinone diazide compound include a naphthoquinone diazide adduct of tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene (for example, TS533, TS567, TS583, TS593 manufactured by Sanpo Chemical Research Institute). ), A naphthoquinone diazide adduct of tetrahydroxybenzophenone (for example, BS550, BS570, BS599 manufactured by Sanpo Chemical Laboratory Co., Ltd.) and the like can be used.

As such a photoacid generator (B), one type may be used alone, or two or more types may be used in combination as appropriate. The blending amount of the photoacid generator (B) is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the polyamic acid (A). Within this range, the balance between the dissolution suppressing effect and the dissolution promoting effect is improved. It is more preferably 10 to 40 parts by mass, further preferably 10 to 35 parts by mass, and particularly preferably 10 to 25 parts by mass.

The other components that can be blended in the photosensitive resin composition of the present invention will be described below.

The solvent (C) can be blended in the positive photosensitive resin composition of the present invention. The solvent (C) is not particularly limited as long as it dissolves (A) polyamic acid, (B) photoacid generator, and other additives. As an example, N, N'-dimethylformamide, N-methylpyrrolidone, N-ethyl-2-pyrrolidone, N, N'-dimethylacetamide, diethylene glycol dimethyl ether, cyclopentanone, γ-butyrolactone, α-acetyl-γ- Butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, dimethylsulfoxide, hexamethylphosphoramide, pyridine, γ-butyrolactone, diethylene glycol monomethyl ether can be mentioned. These may be used alone or in combination of two or more. The amount of the solvent used can be in the range of 50 to 9000 parts by mass with respect to 100 parts by mass of (A) polyamic acid, depending on the coating film thickness and viscosity.

A known sensitizer may be added to the positive photosensitive resin composition of the present invention in order to further improve the photosensitivity.

Further, a known adhesive aid can be added to the positive photosensitive resin composition of the present invention in order to improve the adhesiveness with the substrate.

The positive photosensitive resin composition of the present invention preferably does not contain a compound having a phenolic hydroxyl group.

In addition, various organic or inorganic low molecular weight or high molecular weight compounds may be blended in order to impart processing characteristics and various functionalities to the resin composition of the present invention. For example, colorants, surfactants, leveling agents, plasticizers, fine particles and the like can be used. The fine particles include organic fine particles such as polystyrene and polytetrafluoroethylene, and inorganic fine particles such as colloidal silica, carbon and layered silicate. Further, various colorants, fibers and the like may be blended with the resin composition of the present invention.

[Dry film]
The dry film of the present invention has a resin layer formed by applying the positive photosensitive resin composition of the present invention and then drying the film. The dry film of the present invention is used by laminating a resin layer so as to be in contact with a base material.

The dry film of the present invention is obtained by uniformly applying the positive photosensitive resin composition of the present invention to a carrier film by an appropriate method such as a blade coater, a lip coater, a comma coater, a film coater, etc., and drying the resin. It can be produced by forming a layer and preferably laminating a cover film on the layer. The cover film and the carrier film may be the same film material or different films may be used.

In the dry film of the present invention, as the film material of the carrier film and the cover film, any known one as used for the dry film can be used.

As the carrier film, for example, a thermoplastic film such as a polyester film such as polyethylene terephthalate having a thickness of 2 to 150 μm is used.

As the cover film, a polyethylene film, a polypropylene film, or the like can be used, but one having a smaller adhesive force with the photosensitive resin layer than the carrier film is preferable.

The film thickness of the photosensitive resin layer on the dry film of the present invention is preferably 100 μm or less, more preferably 5 to 50 μm.

Using the positive photosensitive resin composition of the present invention, a pattern film as a cured product thereof is produced, for example, as follows.

First, as step 1, a coating film is obtained by applying a positive photosensitive resin composition onto a substrate and drying it, or by transferring a resin layer from a dry film onto a substrate. As a method of applying the positive photosensitive resin composition on the base material, methods conventionally used for applying the photosensitive resin composition, for example, spin coater, bar coater, blade coater, curtain coater, screen printing A method of applying by a machine or the like, a method of applying by spraying with a spray coater, an inkjet method or the like can be used. As a method for drying the coating film, a method such as air drying, heat drying using an oven or a hot plate, and vacuum drying is used. Further, it is desirable that the coating film is dried under conditions that do not cause imidization of the polyamic acid (A) in the photosensitive resin composition. Specifically, natural drying, blast drying, or heat drying can be performed at 70 to 120 ° C. for 20 minutes to 1 hour. Preferably, it is dried on a hot plate for 20-40 minutes. Vacuum drying is also possible, and in this case, it can be performed at room temperature for 20 minutes to 1 hour.

The base material is not particularly limited, and can be widely applied to silicon wafers, wiring boards, various resins, metals, passivation protective films of semiconductor devices, and the like.

Next, as step 2, the coating film is exposed either through a photomask having a pattern or directly. As the exposure light, one having a wavelength capable of activating (B) the photoacid generator and generating an acid is used. Specifically, the exposed light beam preferably has a maximum wavelength in the range of 350 to 410 nm. As described above, the photosensitivity can be adjusted by appropriately using a sensitizer. As the exposure apparatus, a contact aligner, a mirror projection, a stepper, a laser direct exposure apparatus and the like can be used.

Subsequently, as step 3, heating is performed to imidize a part of the (A) polyamic acid in the unexposed portion. Here, the imidization rate is about 30%. The heating time and heating temperature are appropriately changed depending on (A) polyamic acid, coating film thickness, and (B) type of photoacid generator. Typically, in the case of a coating film thickness of about 10 μm, it takes about 30 seconds to 3 minutes at 110 to 200 ° C. By setting the heating temperature to 110 ° C. or higher, partial imidization can be efficiently achieved. On the other hand, by setting the heating temperature to 200 ° C. or lower, imidization of the exposed portion can be suppressed, the difference in solubility between the exposed portion and the unexposed portion can be increased, and the formation of a pattern film becomes easy.

Then, as step 4, the coating film is treated with a developer. Thereby, the exposed portion in the coating film can be removed to form a pattern film made of the partially imidized (A) polyamic acid on the substrate.

As a method used for development, any method can be selected from conventionally known photoresist developing methods such as a rotary spray method, a paddle method, and a dipping method accompanied by ultrasonic treatment. The developing solution includes inorganic alkalis such as sodium hydroxide, sodium carbonate, sodium silicate and aqueous ammonia, organic amines such as ethylamine, diethylamine, triethylamine and triethanolamine, tetramethylammonium hydroxide and tetrabutylammonium hydroxide. Examples thereof include aqueous solutions of quaternary ammonium salts and the like. Further, if necessary, a water-soluble organic solvent such as methanol, ethanol, isopropyl alcohol or a surfactant may be added in an appropriate amount. Then, if necessary, the coating film is washed with a rinsing solution to obtain a patterned film. Distilled water, methanol, ethanol, isopropanol and the like can be used alone or in combination as the rinsing solution. Moreover, you may use the said solvent (C) as a developer.

Then, as step 5, the pattern film is heated to obtain a cured coating film (cured product). At this time, the polyamic acid (A) may be completely imidized to obtain a polyimide. The heating temperature is appropriately set so that the polyimide pattern film can be cured. For example, heating is carried out at 150 to 300 ° C. for about 5 to 120 minutes in an inert gas. A more preferred range of heating temperature is 150-250 ° C, and a more preferred range is 180-220 ° C. Heating is performed, for example, by using a hot plate, an oven, or a heating oven in which a temperature program can be set. As the atmosphere (gas) at this time, air may be used, or an inert gas such as nitrogen or argon may be used.

The positive photosensitive resin composition of the present invention uses resin materials such as printing inks, adhesives, fillers, electronic materials, optical circuit parts, molding materials, resist materials, building materials, three-dimensional modeling, and optical members. Various known fields / products, especially for a wide range of fields / products in which properties such as heat resistance, dimensional stability, and insulation of polyimide films are effective, such as paints or printing inks, color filters, and flexible displays. It is suitably used as a forming material for films, semiconductor devices, electronic components, interlayer insulating films, wiring coating films, optical circuits, optical circuit components, antireflection films, holograms, optical members, building materials and the like.

In particular, the positive photosensitive resin composition of the present invention is mainly used as a pattern film forming material (resist), and the pattern film formed thereby imparts heat resistance and insulating properties as a permanent film made of polyimide. It functions as a component, for example, color filters, flexible display films, electronic components, semiconductor devices, interlayer insulating films, wiring coating films such as solder resist and coverlay films, solder dams, optical circuits, optical circuit components, and antireflection films. , Other suitable for forming optical or electronic components. Further, since the positive photosensitive resin composition of the present invention is excellent in resolution, it can be suitably used as a pattern film forming material for a package substrate, particularly a wafer level package substrate.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. In the following, "part" and "%" are all based on mass unless otherwise specified.

[Synthesis Example 1: Synthesis of Polyamic Acid A-1]
After putting 30 mmol of the diamine shown in Table 1 below into a separable flask having a capacity of 300 mL, the diamine was dissolved by dehydrated NMP (N-methylpyrrolidone) while flowing nitrogen. After all the diamines were dissolved, 30 mmol of the acid anhydride shown in Table 1 below was gradually added. The acid anhydride adhering to the wall of the flask was poured into the reaction solution with a small amount of NMP, and then stirred and reacted at room temperature for 24 hours to obtain a varnish of 15% by mass of polyamic acid (PAA) A-1. The amount of dehydrated NMP input was 75% by mass of the amount of PAA varnish. As the acid anhydride "TDA" in the table, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride (new). Ricacid TDA-100) manufactured by Nippon Rikasha Co., Ltd. was used. As the diamine "4,4'-ODA", 4,4'-diaminodiphenyl ether (manufactured by Wakayama Seika Co., Ltd.) was used.

[Synthesis Examples 2 and 3: Synthesis of Polyamic Acids A-2 and A-3]
Varnishes of polyamic acids A-2 and A-3 were obtained in the same manner as in Synthesis Example 1 except that the diamine and the acid anhydride were changed to the compounds shown in Table 2 below. As the acid anhydride "PPHT" in the table, N, N'-bis (1,2-cyclohexanedicarboxylic acid anhydride-4-yl) carbonyl-1,4-phenylenediamine (manufactured by Nippon Seika Co., Ltd.) is used. There was. As the diamine "3,4'-ODA", 3,4'-diaminodiphenyl ether (manufactured by Nichijun Chemical Co., Ltd.) was used.

[Synthesis Example 4: Synthesis of Polyamic Acid A-4]
After putting 30 mmol of the diamine shown in Table 3 below into a separable flask having a capacity of 300 mL, the diamine was dissolved by dehydrated NMP (N-methylpyrrolidone) while flowing nitrogen. After all the diamines were dissolved, 22.5 mmol of the acid anhydride TDA and 7.5 mmol of PMDA shown in the table below were gradually added. The acid anhydride adhering to the wall of the flask was poured into the reaction solution with a small amount of NMP, and then stirred and reacted at room temperature for 24 hours to obtain a varnish of 15% by mass of polyamic acid (PAA) A-4. The amount of dehydrated NMP input was 75% by mass of the amount of PAA varnish. As the acid anhydride "PMDA" in the table, pyromellitic anhydride (manufactured by Mitsubishi Gas Chemical Company, Inc.) was used.

[Synthesis Example 5: Synthesis of Polyamic Acid A-5]
A varnish of polyamic acid A-5 was obtained in the same manner as in Synthesis Example 4 except that the amount of acid anhydride was changed to 15 mmol of TDA and 15 mmol of PMDA.

[Synthesis Example 6: Synthesis of Polyamic Acid A-6]
A varnish of polyamic acid A-6 was obtained in the same manner as in Synthesis Example 4 except that the amount of acid anhydride was changed to 7.5 mmol of TDA and 22.5 mmol of PMDA.

[Comparative Synthesis Examples 1 and 2: Synthesis of Polyamic Acids R-1 and R-2]
Varnishes of polyamic acids R-1 and R-2 were synthesized in the same manner as in Synthesis Example 1 except that the diamine and acid anhydride were changed to the compounds shown in Table 4 below. As the acid anhydride "CBDA" in the table, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (manufactured by Shin Nihon Pharmaceutical Co., Ltd.) was used.

(Examples 1 to 11 , 13 to 16, Reference Example 12, Comparative Examples 1 to 3)
In the combinations shown in Table 5, a photoacid generator was blended with a polyamic acid varnish and dissolved to obtain photosensitive resin compositions of Examples , Reference Examples and Comparative Examples. The blending amount of the photoacid generator in the table is the blending amount of the polyamic acid varnish per 100 parts by mass of the solid content.

[Method of forming a positive pattern film]
After making the varnish concentration uniform using a stirring / defoaming device, each of the photosensitive resin compositions of Examples , Reference Examples and Comparative Examples was applied onto a silicon substrate using a spin coater, and the temperature was 100 ° C. on a hot plate. The mixture was dried for 30 minutes to obtain a dry coating film of a photosensitive resin composition having a film thickness of about 5 μm. Only half of the mask (transmittance 0%) was placed on the dry coating film, and 1J broad exposure was performed with a desktop exposure apparatus (manufactured by Sanaga Electric Co., Ltd.) equipped with a high-pressure mercury lamp. Next, post-exposure heating (PEB) was performed on a hot plate under the conditions shown in Table 5. This was developed with a 1% NaOH aqueous solution or a 1% Na ₂ CO ₃ aqueous solution, rinsed with water, and dried at room temperature to obtain a positive pattern film. Table 5 shows the amount of the photoacid generator added, the PEB conditions, and the contrast evaluation results.

[Evaluation of contrast]
The above contrast was calculated by the following formula.
Contrast = exposed area development speed (thickness μm / development time min) / unexposed area development speed (thickness μm / development time min)
Film thickness (μm): A value obtained by subtracting the film thickness after development from the film thickness before development Development time (min): Time of immersion in a developing solution The evaluation was made as follows according to the contrast value.
⊚: 10 or more 〇: 2 or more and less than 10 Δ: 1 or more and less than 2 ×: None (not dissolved)

[Table 5]
* 1: TS583, DNQ (diazonaphthoquinone) manufactured by Sanpo Chemical Research Institute.
* 2: WPAG-149 manufactured by Wako Pure Chemical Industries, Ltd. (2-methyl-2-[(4-methylphenyl) sulfonyl] -1-[(4-methylthio) phenyl] -1-propane)

[Formation of fine positive pattern film]
The photosensitive resin composition of Example 8 was made uniform in varnish concentration using a stirring / defoaming device, then applied onto a silicon substrate using a spin coater, dried on a hot plate at 100 ° C. for 30 minutes, and filmed. A dry coating film of a photosensitive resin composition having a thickness of about 5 μm was obtained. On this dry film, photomasks having a fine line pattern of L / S = 3/3 μm, 7/7 μm, and 9/9 μm were placed, respectively, and 300 mJ of broad light was exposed using a mask close contact exposure stage (Risotec Japan). .. Then, PEB at 160 ° C. for 1 minute was performed on a hot plate. This was developed with a 1% Na ₂ CO ₃ aqueous solution, rinsed with water and dried at room temperature to obtain a positive pattern film. A micrograph of the obtained positive pattern film is shown in FIG. Table 6 shows the steps (difference between the surface of the line and the surface of the space portion).

(Examples 17 to 20)
[Evaluation of glass transition temperature]
Photoacid generator B-1 (TS583, DNQ (diazonaphthoquinone) manufactured by Sanpo Chemical Laboratory Co., Ltd.) is 0 with respect to 3 g of 15% by mass varnish of polyamic acids A-1, A-4, A-5, and A-6. .0675 g was added to obtain the photosensitive resin compositions of Examples 17 to 20. The obtained photosensitive resin composition was applied onto a silicon wafer with an applicator, heated on a hot plate at 100 ° C. for 10 minutes, and then heat-treated at 200 ° C. for 30 minutes to prepare a cured film. This cured film was peeled off from the silicon wafer, and the glass transition temperature (Tg) was measured. Tg was measured using a dynamic viscoelasticity measuring device RSA-G2 manufactured by TA Instrument under the conditions of 50 ° C. to 350 ° C., a heating rate of 10 ° C./min, and a frequency of 1 Hz.

From the results shown in Tables 5 and 6 and FIG. 1, it can be seen that the photosensitive resin composition of the present invention has excellent contrast and a high-resolution positive pattern film can be obtained. In particular, even when L / S = 3/3 μm, the step is large, the dissolution promoting effect and the dissolution inhibiting effect are obtained, and it can be seen that the resolution is excellent. On the other hand, in the photosensitive resin composition of the comparative example in which another polyamic acid was blended instead of the specific polyamic acid in the present invention, contrast could not be obtained and a positive pattern film could not be formed.

Further, as shown in Tables 5 and 7, for (A) polyamic acid, TDA is used as an acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton, and another acid anhydride to be copolymerized is selected. Therefore, it is possible to obtain a material having excellent resolution and imparted heat resistance.

Claims (9)

(A) An acid anhydride having a cyclic aliphatic skeleton and an aromatic skeleton, a polyamic acid obtained from a diamine, and
(B) Containing a photoacid generator
A positive photosensitive resin composition containing no compound having a phenolic hydroxyl group.
The polyamic acid (A) has the following general formula (II):
(In the formula, R ₂ is a divalent organic group having a plurality of aromatic rings and the aromatics are directly bonded to each other or bonded via a (thio) ether group, and X is a divalent organic group. It is a group, m is an integer of 1 or more, and n is an integer of 0 or 1 or more.)
It is a compound having a structure represented by
The positive photosensitive resin composition, wherein the polyamic acid (A) is a compound that has not been imidized. The polyamic acid (A) has the following general formula (V):
(In the formula, R ₂ is a divalent organic group having a plurality of aromatic rings and the aromatics are directly bonded to each other or bonded via a (thio) ether group, and R ₄ and R ₆ are. It is a divalent organic group and
R ₃ and R ₅ are tetravalent organic groups having a substituted or unsubstituted aromatic skeleton.
m is an integer of 1 or more, n and s are independently integers of 0 or 1 or more, and at least one of n and s is an integer of 1 or more. )
The positive photosensitive resin composition according to claim 1, wherein the compound has a structure represented by. The positive photosensitive resin composition according to claim 1 or 2, wherein the amount of the (B) photoacid generator to be blended is 1 to 50 parts by mass with respect to 100 parts by mass of the (A) polyamic acid. An exposure process for exposing the coating film of the positive photosensitive resin composition and
A heating step of heating the coating film after the exposure step and
The positive photosensitive resin composition according to any one of claims 1 to 3, which is used in a method for forming a pattern film including a developing step of developing after the heating step. A dry film having a resin layer obtained by applying the positive photosensitive resin composition according to any one of claims 1 to 4 to a film and drying the film. A method for producing a pattern film having an L / S of 9/9 μm or less, which comprises curing a coating film composed of the positive photosensitive resin composition according to any one of claims 1 to 4. A method for producing a pattern film having an L / S of 9/9 μm or less, which comprises curing a coating film composed of a resin layer of a dry film according to claim 5. A method for manufacturing a printed wiring board , which comprises manufacturing a pattern film having an L / S of 9/9 μm or less by the method for manufacturing a pattern film according to claim 6. A method for manufacturing a printed wiring board , which comprises manufacturing a pattern film having an L / S of 9/9 μm or less by the method for manufacturing a pattern film according to claim 7.