JPS63239998A - Manufacture of wiring material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing wiring materials, and more particularly, to a method for manufacturing wiring materials for protected printed wiring boards, integrated circuits, and the like.

[Prior Art] In recent years, with the development of electrical equipment and electronic equipment, the wiring materials used therein have become extremely diverse, and the required characteristics are also becoming stricter year by year.

Conventionally, this type of wiring material includes flexible printed circuit boards, rigid printed circuit boards, integrated circuits, etc., and the main purpose of insulation is insulation on the wiring.
i is provided.

For example, in the case of a printed circuit board, techniques such as pressing a heat-resistant film coated with an adhesive as a coverlay film, or coating the board with a resin solution are used.

However, in the former case, even though a heat-resistant film is used, the heat resistance of the adhesive is low, so
There has been a problem in that the adhesive oozes into through-holes, etc., or causes swelling or peeling when heated due to solder or the like. Further, in the latter case, although no adhesive is used, there is a problem in that the heat resistance of the commonly used resin is low, causing various problems during soldering.

As a means to solve such problems, it has been proposed to directly apply a low thermal expansion polyimide resin solution onto the circuit (Japanese Patent Laid-Open No. 61-178.196@, Japanese Patent Laid-open No. 61-178.
1-212.096 and 60-208.358).

However, even in this case, the thermal expansion is still insufficiently low, causing curls in the wiring board, and it is necessary to blend an inorganic material to roughly lower the thermal expansion.

On the other hand, even in the case of integrated circuits, coating with a polyimide resin solution is performed for the purpose of improving insulation properties, α-ray shielding, water resistance, etc.

These are generally passivation films, interlayer insulation films,
They are called α-ray shielding films, buffer coat films, etc. (
19B4.8.27 Nikkei Electronics).

When used in these applications, as the degree of integration increases, problems arise such as wires breaking due to distortion between the resin and the circuit, reducing reliability. This is thought to be mainly due to the difference in thermal expansion coefficient between the circuit and the resin.

Therefore, as a solution to this problem, it has been proposed to use polyimide with low thermal expansion (Japanese Patent Application Laid-Open No. 60-32
, No. 827 and JP-A-61-176, 196@), there were problems in that the thermal expansion was not sufficiently low and the adhesion to the wafer was not sufficient.

[Problems to be Solved by the Invention] In order to solve the above-mentioned problems, the present inventor conducted various studies and found that a polyamide-imide resin having a specific structure has low thermal expansion and excellent adhesion to conductors. The present invention was completed based on the discovery that

Therefore, an object of the present invention is to manufacture a wiring material with excellent performance by directly coating a circuit with a heat-resistant resin that has low thermal expansion and excellent adhesion to a conductor to provide protection such as insulation. The goal is to provide a method for

[Means for solving the problem] A group represented by any of the following (wherein R1 to R8 represent a lower alkyl group, a lower alkoxy group, or a halogen, and may be the same or different from each other, n1 to n8 represent integers from O to 4), and a solution of a polyamide-imide resin precursor compound having a structural unit represented by "2 is a tetravalent aromatic residue" was applied onto the insulating layer. This is a manufacturing method of a wiring material in which the wiring material is coated on a circuit formed in the same manner and then imidized, thereby forming a polyamide-imide resin coating on the circuit.

As the resin solution used in the present invention, one containing a polyamideimide precursor compound having a structural unit represented by the above general formula (I) is used.

This polyamideimide precursor compound is diamide (however,
(wherein R1 to R8 and n1 to n8 are the same as above) and an aromatic tetracarboxylic dianhydride are used as main raw materials and are obtained by reacting them.

The lower alkyl group and lower alkoxy group that can be introduced as a substituent into the diamine component preferably have less than 10 carbon atoms, and if they have 10 or more carbon atoms, it is difficult to achieve low thermal expansion.

As the diamine component, preferably 4,4°-diaminobenzanilide, 4,3°-diaminobenzanilide, 3
, 4°-diaminobenzanilide and substituted derivatives thereof. Substituents are methyl group, ethyl group, propyl group,
Preferred are methoxy group, ethoxy group, fluorine, chlorine, bromine and the like.

More preferably, the following general formula (where R9 to
R12 represents the same or different lower alkyl group, lower alkoxy group, halogen or hydrogen, at least one of which is a methoxy group), and most preferably 2-methoxy-4,4゛-Diaminobenzanilide.

Two or more such diamine compounds may be used simultaneously.

Aromatic tetracarboxylic dianhydride is (however, in the formula ^
r2 is the same as above), pyromellitic dianhydride, 3,3°, 4.4゛-biphenyltetracarboxylic dianhydride, 3,3°, 4,4° -benzophenone tetracarboxylic dianhydride, 3.3', 4,
Mention may be made of 4°-diphenylsulfone tetracarboxylic dianhydride. Pyromellitic dianhydride is preferred for its low thermal expansion effect, but two or more types of tetracarboxylic dianhydride may be used for the purpose of improving physical properties, adhesion, etc.

The polymerization reaction involves N-methyl-2-pyrrolidone (NMP),
N,N-dimethylformamide (DMF), N,N-
It is carried out in a solvent such as dimethylacetamide (DMAC>, dimethylsulfoxide (DMSO), dimethylsulfolane sulfate, butyrolactone, cresol, halogenated phenol, diglyme, etc.) at a temperature of 0 to 200°C,
A polyamide-imide precursor solution is obtained by this, but the reaction solvent is preferably D from the viewpoint of reactivity.
MAC, and the reaction temperature is preferably 0 to 100, since it becomes difficult to obtain the low thermal expansion resin used in the present invention when the imidization reaction progresses during the polymerization reaction.
℃ range.

In the present invention, after applying the polyamideimide precursor solution, which is a polyamic acid obtained in this way, onto a circuit formed on an insulating layer, drying and imidization reaction are performed. The structural unit of polyamideimide represented by I) is preferably contained in an amount of 50 mol% or more, more preferably 60 mol% or more. 50 mol%
If the amount is less, the effect of reducing thermal expansion will be reduced and it may be difficult to obtain a wiring material with less curl.

As for other structural units, various diamines and tetracarboxylic acid compounds can be copolymerized or separately synthesized polyimide or its precursor and polyamideimide can be blended.

Specific examples include phenylenediamine, m-phenylenediamine, 4,4°-diaminodiphenyl ether, 4,4゛-diaminodiphenylmethane, 3.3゛-dimethyl-4,4゛-diaminodiphenylmethane, 2
．． 2-bis(4-(4-aminophenoxy〉phenyl)
Propane, 1,2-bis(anilino)ethane, diaminodiphenylsulfone, diaminodiphenylsulfide,
Diaminobenzoate, 2,2-bis(p-aminophenyl)propane, 2,2-bis(p-aminophenyl)hexafluoropropane, 1,5-diaminonaphthalene,
Diaminotoluene, diaminobencytrifluoride,
1,4-bis(aminophenoxy)benzene, 4.4
”-bis(aminophenoxy)biphenyl, diaminoanthraquinone, 4,4°-bis(3-aminophenoxyphenyl〉diphenylsulfone, 1,3-bis(anilino)hexafluoropropane, 1,4-bis(anilino) Octafluorobutane, 1,5-bis(anilino)
Decafluoropencune, 1,7-bis(anilino)teI
~ Radecafluorohebutane, general formula % formula % (However, in the formula, R14 and RIB are divalent organic groups,
R13 and R15 are monovalent groups, p and q are 1
diaminotoluene, which is a larger integer)
2.2-bis(4-(aminophenoxy)phenyl)
Hexafluoropropane, 2,2-bis(4-(3-7
minophenoxy) phenyl) hexafluoropropane,
2.2-bis(4-(2-aminophenoxy〉phenyl)hexafluoropropane, 2.2-bis(4-(4-
Aminophenoxy)-3,5-dimethylphenyl)hexafluoropropane, 2,2-bis(4-(4-aminophenoxy)-3,5-ditrifluoromethylphenyl)hexafluoropropane, Kanobis(4- Amino-2-
trifluoromethylphenoxy)benzene, 4,4°-
Bis(4-amino-2-trifluoromethylphenoxy)biphenyl, 4,4°-bis(4-amino-3-trifluoromethylphenoxy)biphenyl, 4,4"-bis(4-amino-2-trifluoro methylphenoxy)
Diphenylsulfone, 4°4°-bis(3-amino-5
-Trifluoromethylphenoxy〉diphenylsulfone, 2,2-bis(4-(4-amino-3-trifluoromethylphenoxy)phenyl)hexafluoropropane, benzidine, 3°3',5,5°-tetramethyl Benzidine, octafluorobenzidine, 3,3゛-methoxybenzidine, 〇-tolidine, m-tolidine, 2,2゛
, 5.5', 6.6'-hexafluorotridine, 4,
There are diamines such as 4°"-diaminoterphenyl and 4.4111-diaminoquaterphenyl, and diisocyanates obtained by reacting these diamines with phosgene and the like.

In addition, examples of tetracarboxylic acids and derivatives thereof include the following. Although exemplified here as tetracarboxylic acid, esterified products, acid anhydrides,
Of course, acid chlorides can also be used.

2.3.3', 4°-diphenylethertetracarboxylic acid, 2,3.3", 4°-benzophenonetetracarboxylic acid, 2°3,6.7-naphthalenetetracarboxylic acid, 1,4,5.7 -naphthalenetetracarboxylic acid, 1,
2,5.6-naphthalenetetracarboxylic acid, 3.3°,
4.4'-diphenylmethanetetracarboxylic acid, 2,2
-bis(3,4-dicarboxyphenyl)propane, 2
．． 2-bis(3,4-dicarboxyphenyl)hexafluoropropane, 3.4.9.10-tetracarboxyperylene, 2.2-bis(4-(3°4-dicarboxyphenoxy)phenyl)propane, 2.2-bis(4-
Examples include (3,4-dicarboxyphenoxy)phenyl)hexafluoropropane, butanetetracarboxylic acid, cyclopentanetetracarboxylic acid, and trimellitic acid and its derivatives.

Furthermore, it is also possible to introduce a crosslinked structure or ladder structure by modifying with a compound having a reactive functional group.

For example, there are the following methods.

(i) General formula (wherein R17 is an aromatic organic group of 2+ x fi, Z is an NH2 group, a CON+-12 group, a SO2NH2
Introducing a pyrrolone ring, indoquinazolinedione ring, etc. by modifying with a compound represented by a group selected from the following, which is at the ortho position to the amine group, and where X is 1 or 2. do.

(11) Amine, diamine having a polymerizable unsaturated bond,
It is modified with dicarboxylic acid, tricarboxylic acid, and tetracarboxylic acid derivatives to form a crosslinked structure upon curing. As the unsaturated compound, maleic acid, nadic acid, tetrahydrophthalic acid, ethynylaniline, etc. can be used.

(iii) modified with an aromatic amine having a phenolic hydroxyl group or a carboxylic acid, and this water M! Alternatively, a network structure is formed using a bridge or c-agent that reacts with a carboxyl group.

The coefficient of linear expansion can be adjusted by modifying using each of the above components. In other words, a polyamideimide resin consisting only of the structure of the general formula (I>) has a structure of 1 x 10-5
It is possible to form a resin layer with a coefficient of linear expansion below , but by modifying this with each of the above components, the coefficient of linear expansion can be arbitrarily increased, approaching the coefficient of linear expansion of the circuit conductor. is possible.

In order to obtain the low thermal expansion resin layer in the present invention, it is desirable to coat the resin layer on the circuit in the form of a polyamideimide precursor.

Even if a normal polyamide-imide solution is applied, a resin layer with low thermal expansion cannot be obtained. Any coating method can be used.

The solvent drying temperature and imidization temperature can be arbitrarily selected.

The solvent drying temperature is preferably 150°C or lower, more preferably 120°C or lower.

The maximum imidization temperature is usually 200°C or higher, preferably 300°C or higher.

The present invention is applicable to any wiring material, preferably printed circuits and integrated circuits due to its effectiveness.

In the case of printed circuits, the manufacturing method of the present invention has a temperature of 200'C.
Since the above heat treatment is required, more heat-resistant substrates are preferred, such as glass polyimide circuit boards, flexible printed circuit boards using polyimide adhesives, non-adhesive flexible printed circuit boards, ceramic circuit boards, and metal bases. Examples include circuit boards and the like. Furthermore, in the case of integrated circuits, a polyimide resin solution is usually spin-coded onto the integrated circuit and used for various purposes, such as passivation films, interlayer insulating films, α-ray shielding films, buffer coat films, etc. In other words, it can also be used as a resin sealing method for integrated circuits.

For the purpose of improving the adhesion between these circuits and the polyamide-imide resin, it is also possible to perform an arbitrary base treatment on the circuit board in advance. Examples include zaiding, aluminum alcoholade, aluminum chelate, silane coupling agent, alkali treatment, ozone treatment, flame treatment, corona discharge treatment, glow discharge treatment, and the like.

In the present invention, inorganic, organic or metal powders, fibers, chopped The strands etc. may be mixed into the resin solution.

[Function] In the method of the present invention, a layer of low thermal expansion resin is formed, so distortion with the circuit can be reduced, curling can be reduced, and reliability can be improved. .

[Examples] Hereinafter, the present invention will be specifically explained using Examples, Synthesis Examples, and Comparative Examples, but the present invention is not limited thereto.

The flexible printed circuit board used in the examples was made of a commercially available polyimide film (Upilex S) with a thickness of 25μ.
: registered trademark) and a commercially available electrolytic copper foil with a thickness of 35 μm, using a commercially available polyimide adhesive (LARC-PI, 20 μm thick).
After bonding using L), a circuit was formed by etching into an arbitrary pattern.

The coefficient of linear expansion was measured using a thermomechanical analyzer (TMA) using a sample that had undergone sufficient imidization reaction, and was heated to 250°C and then cooled at a rate of 10'C/min from 240°C to 100°C. The average coefficient of linear expansion was calculated.

After forming the insulating layer on the circuit board, curl 50sX
It was cut out to a size of 50 g, and its radius of curvature was determined and used as a guide.

The abbreviations for each item are as follows.

P) 108: Pyromellitic dianhydride BPDA: 3,3°, 4,4-hyphenyltetracarboxylic dianhydride BTDA: 3.3', 4.4°-benzophenonetetracarboxylic dianhydride DDE :4,4°-diaminodiphenyl ether 001
(:4,4°-diaminodiphenylmethane o-TLDN
: o-tolidine DABA:H2N (XNHCO-@-N H2)fo
To B Haccho: BAP Hachi: Town N-@-CONH (C seaht+co
NH2DHAC dimethylacetamide NHP: N-methyl-2-pyrrolidone Synthesis Example 1 200 d/min of nitrogen was flowed into a 300 d four-loaf flask equipped with a thermometer, calcium chloride tube, stirring rod, and nitrogen inlet. while 0.085 mol DABA, 0.01
5 mol of DD) and 170 d of DHAC were added and stirred. DABA could not be dissolved. While cooling this solution to below 10°C in a water cooling bath, 0°1 mol of P) (()
When A was gradually added, a polymerization reaction occurred while gradually dissolving in ()AB, and a viscous polyamic acid (polyamideimide precursor) was obtained.

Synthesis Example 2 200m/min in a 300rn1 four-loaf flask equipped with a thermometer, calcium chloride tube, stirring rod and nitrogen inlet
0.075 mol of NoDABA while flowing 1 of nitrogen.
and 170 d of DHAc were added and stirred.

All in HoDAB could not be dissolved. While cooling this solution to 10° C. or lower in a water cooling bath, 0.075 mol of PMOA was gradually added, and NoDABA underwent a polymerization reaction while gradually dissolving, to obtain a viscous solution.

This is supplemented with 0.025 mol of O leaves and 0.025 mol of BT.
DA was added and stirred roughly to obtain a block type polyamic acid (polyamideimide precursor).

Synthesis Examples 3 to 5 In Synthesis Example 2, instead of NoDABA) fDABA
, )t.

Using BATA and BATA, 1 q of polyamic acids of Synthesis Examples 3 to 5 were obtained.

Synthesis Example 6 Similar to Synthesis Example 1, 0.1 mol of 4.3'-HoDA
Polyamic acid was produced by reacting I3A with 0.1 mol of PMOA.

Example 1 The resin solution of Synthesis Example 1 was applied onto a flexible printed circuit board and dried for 30 minutes in a hot air dryer at 90°C.
130℃ 10 minutes, 150℃ 10 minutes, 250℃ 3 minutes, 30
An imidization reaction was performed by heat treatment at 0° C. for 3 minutes to form a resin layer with a thickness of 25 μm.

The curl radius of the obtained board was measured, and the adhesion between the circuit board and the resin layer was examined by hand kneading test 10 times, and the linear expansion coefficient of the resin layer was measured. The results are shown in Table 1.

Examples 2 to 6 Using the resin solutions of Synthesis Examples 2 to 6, a circuit board was prepared in the same manner as in Example 1. A was manufactured, and its curl radius of curvature, adhesion, and coefficient of linear expansion were measured. The results are shown in Table 1.

Comparative Example 1 In the same manner as in Synthesis Example 1, 0.1 mol of DI)E and 0.1 mol of PMDA were reacted to obtain a polyamic acid.

This resin solution was used to coat a flexible printed circuit board in the same manner as in Example 1, and its curl radius, adhesion force, and coefficient of linear expansion were measured. The results are shown in Table 1.

Comparative Example 2 In the same manner as in Synthesis Example 1, 0.1 mol of DD)l and 0.1 mol of BTDA were reacted to obtain a polyamic acid.

This resin solution was used to coat a flexible printed circuit board in the same manner as in Example 1, and its curl radius, adhesion force, and coefficient of linear expansion were measured. The results are shown in Table 1.

Comparative Example 3 Similar to Synthesis Example 1, 0.1 mol of o-TLDN and 0°1
Mol of P)IOA was reacted in 170d of NMP to obtain a polyamic acid.

This resin solution was used to coat a flexible printed circuit board in the same manner as in Example 1, and its curl radius, adhesion force, and coefficient of linear expansion were measured. The results are shown in Table 1.

(Note) Defective: Peeling is observed.

Example 7 After etching a glass polyimide veneer with a thickness of 0.75 m to create a circuit, the resin solution of Synthesis Example 2 was applied, and 9
After drying in a hot air dryer at 0°C for 30 minutes, an imide reaction was performed by heat treatment at 130°C for 10 minutes, 150°C for 10 minutes, 250°C for 3 minutes, and 300°C for 3 minutes to form a resin layer with a thickness of 50 μm. . This wiring board was flat with almost no curls.

Comparative Example 4 Similarly to Example 7, the resin solution synthesized in Comparative Example 1 was applied onto a glass polyimide circuit board to form a resin layer, and the curling property was examined. It never stopped.

Comparative Example 5 In the same manner as in Example 7, the resin solution synthesized in Comparative Example 3 was applied onto a glass polyimide circuit board to form a resin layer, and the curling properties were examined. I couldn't stand it.

Example 8 and Comparative Example 6.7 Using the resin solutions of Synthesis Example 2, Comparative Example 1, and Comparative Example 3,
A resin layer having a thickness of 60 μm was formed by spin-coding as an α-ray shielding film on an integrated circuit of a silicon wafer having a diameter of 4 inches. Heat treatment conditions include hot air drying at 90°C for 30 minutes, followed by 130°C for 10 minutes, 150°C for 10 minutes, and 250°C.
The imidization reaction was performed by heat treatment at 300°C for 3 minutes.

The wafers using the resin solution of Synthesis Example 2 were almost flat and flat, but the wafers using the resin solutions of Comparative Examples 1 and 3 were greatly curved, making subsequent processing difficult.

In addition, when a cellophane tape peeling test was conducted using the base grain test method, no peeling was observed with the resin solution of Synthesis Example 2 and excellent adhesion, but the adhesive strength of the adhesive tape with the resin solutions of Comparative Examples 1 and 3 was excellent. Peeling was observed in about 30 out of 100 squares.

[Effects of the Invention] The wiring material produced by the method of the present invention has fewer problems such as curling and is highly reliable.

Claims (6)

[Claims] (1) The following general formula (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) [However, Ar1 in the formula is the following general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, ▲ Numerical formulas, chemical formulas, tables, etc. There is a group represented by either ▼ or ▲ There is a mathematical formula, chemical formula, table, etc. n1 to n8 are integers of 0 to 4), and Ar2 is a tetravalent aromatic residue] A solution of a polyamideimide resin precursor compound having the structural unit represented by A method for producing a wiring material, which comprises applying the material onto a circuit formed on a body and then imidizing the material. (2) In general formula (I), a patent where Ar1 is a group represented by ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, in the formula, R1 and R2 and n1 and n2 are the same as above) A method for manufacturing a wiring material according to claim 1. (3) In the general formula (I), Ar1 has a numerical formula, chemical formula, table, etc. (However, in the formula, R9 to R12 represent the same or different lower alkyl group, lower alkoxy group, halogen, or hydrogen, and The method for producing a wiring material according to claim 1, wherein at least one is a methoxy group. (4) The method for producing a wiring material according to claim 1, wherein in general formula (I), Ar1 is a group represented by ▲a mathematical formula, a chemical formula, a table, etc.▼. (5) The method for manufacturing a wiring material according to any one of claims 1 to 4, wherein the wiring material is a printed circuit board. (6) The method for manufacturing a wiring material according to any one of claims 1 to 4, wherein the wiring material is an integrated circuit.