JP2002064252A - Polyimide film, laminate using the same, and multilayered wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyimide film and a laminate suitable for obtaining a laminate, from which an electroless plating film having a high adhesive strength and a small surface roughness can be obtained and a multilayered wiring board having high heat resistance, narrow pitched wiring patterns and small-sized vias, an uniform insulation layer thickness and an adequately low linear expansion coefficient, using the laminate. SOLUTION: The polyimide film contains an electroless plating catalyst. The laminate has an adhesive layer using the same on one surface. The multilayered wiring board uses the laminate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyimide film containing an electroless plating catalyst, and a laminated body and a multilayer wiring board using the same. And a polyimide film capable of providing a multi-layer wiring board having a high heat resistance, a narrow pitch wiring pattern, a small diameter via, a uniform insulating layer thickness, and a moderately low coefficient of linear expansion. TECHNICAL FIELD The present invention relates to a body and a multilayer wiring board using the same.

[0002]

2. Description of the Related Art As electronic devices become smaller, have higher performance, and have higher functions, printed wiring boards are required to be able to cope with high-density mounting. In order to meet the demand, multilayer wiring boards, thinner insulating layers, adoption of interstitial via holes in place of conventional through holes, reduction in via diameter, narrower circuit pitch, and the like are progressing.

As a technique for realizing these, there is a multilayer wiring board manufacturing technique by a build-up method. The manufacture of the build-up wiring board is performed by various manufacturers by various methods. Among them, the method using copper foil with insulating adhesive is adopted by many wiring board manufacturers because the material is easy to handle and the process can be significantly shortened because the conductor layer has already been formed. Have been.

[0004] The copper foil with an insulating adhesive has a two-layer structure of a copper foil and an adhesive layer, and is manufactured by a method of applying a solution adhesive on the copper foil and drying. For example, a general build-up multilayer wiring board using a copper foil with an insulating adhesive is manufactured as follows.

[0005] A copper foil with an insulating adhesive is laminated on a copper-clad laminate containing a glass cloth on which a circuit has been formed and through-hole processed in advance by a method such as press working or roll laminating.
Subsequently, a via penetrating the adhesive layer and the copper foil layer is formed by laser drilling. Next, the via is made conductive by electroless plating. After the electrolytic plating, the copper foil of the copper foil with an insulating adhesive is formed into a circuit pattern by an etching method. Again, a copper foil with an insulating adhesive is laminated and the same process is repeated to produce a build-up multilayer wiring board.

[0006] The build-up multilayer wiring board is required to be further enhanced in the future. However, it has been pointed out that the conventional copper foil with insulating adhesive has some problems. That is, in order to produce a circuit pattern having a narrow pitch by an etching method, it is advantageous in terms of yield to make the thickness of the conductor layer to be etched thinner. However, the copper foil thickness of a conventional copper foil with an insulating adhesive is generally 18 μm, and at least 12 μm even when thin, and there is a limit in producing a circuit pattern having a narrow pitch.

In order to form a via by laser drilling, a smaller diameter of the via can reduce the aspect ratio and facilitate processing. However, for this purpose, it is necessary to reduce the thickness of the insulating layer. However, when the thickness of the insulating layer of the conventional copper foil with an insulating adhesive is reduced, it becomes difficult to make the thickness of each insulating layer when laminated. In addition, there is a problem in that the insulating property is reduced, and it is difficult to secure the electrical reliability.

[0008] Further, thinner and lighter multi-layer wiring boards are also required. However, a copper-clad laminate containing glass cloth, which is usually used as a core layer of a build-up wiring board, has a thickness of 400 μm.
m, and because glass is used, it is heavy and does not satisfy the above requirements as a material. In addition, when a multilayer board is manufactured using only a copper foil with an insulating adhesive instead of the glass cloth-containing copper-clad laminate, a thinner and lighter weight can be obtained, but sufficient rigidity cannot be obtained. Since they exhibit a large coefficient of linear expansion derived from the insulating adhesive, none of them is durable for use because it lacks mounting reliability.

[0009] Here, the polyimide film can ensure good insulating properties and maintain electrical reliability.
It can be used as an insulator layer of a printed wiring board that satisfies demands for thinner and lighter weight.

However, when a polyimide film is used as the insulating layer, in the electroless plating step for forming the conductor layer, the electroless plated copper does not adhere firmly depending on the ordinary electroless plating step. Then, it is not suitable for practical use.

[0011]

The problem to be solved by the present invention is to provide a polyimide film suitable for manufacturing a build-up wiring board and a laminate using the same. When the electroless plating is performed on the laminate, the resulting metal has a smooth surface and is suitable for high-frequency circuits, and the adhesion to the polyimide film becomes strong, high heat resistance, a narrow pitch wiring pattern, and a small diameter via The present invention provides a multilayer body which satisfies the above requirements, realizes a multilayer wiring board having a uniform insulating layer thickness and a moderately low linear expansion coefficient, and a multilayer wiring board using the same.

[0012]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by the following polyimide film and laminate, and have reached the present invention.

That is, a first aspect of the present invention is to provide a polyimide film containing an electroless plating catalyst, which is produced by mixing an electroless plating catalyst in a polyamic acid production step as a precursor, according to the present invention. 2 is a polyimide film containing an electroless plating catalyst produced by applying or dipping an electroless plating catalyst in the state of a gel film.
A polyimide film having a tensile modulus of at least a,
A fourth aspect of the present invention is to provide a polyimide film having a linear expansion coefficient of 2.0 × 10 ⁻⁵ / ° C. or less as the fifth aspect of the present invention.
In the sixth aspect of the present invention, the polyimide film having a water absorption of 1.5% or less is selected from gold, silver, ruthenium, rhodium, palladium, osmium, iridium, and platinum. A polyimide film containing at least one or more elements to be formed, a seventh aspect of the present invention is a laminate in which an adhesive layer is formed on one side of the polyimide film according to any one of the above, a eighth aspect of the present invention is a laminate. The polyimide film according to any one of the above, which contains an electroless plating catalyst on one surface and has an adhesive layer on the other surface, a laminate, wherein the adhesive layer is a thermosetting resin. The laminated body according to any one of the above, which comprises a resin composition containing the polyimide film according to the tenth aspect and / or the laminate according to any one of the above. A multi-layer wiring board, each with the contents.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The polyimide film of the present invention
Contains an electroless plating catalyst. A laminate using this has an adhesive layer on one side of a polyimide film. Furthermore, the multilayer wiring board of the present invention uses the polyimide film and / or the laminate of the present invention.

In the polyimide film of the present invention, the electroless plating catalyst is already contained on the surface and / or inside of the polyimide film. When a build-up wiring board is prepared using the laminate of the present invention provided with an adhesive layer, a method such as impregnation with an electroless plating solution, without including a roughening step, is firmly applied to the polyimide film surface. Glued,
In addition, a conductor layer having a smooth surface can be formed. Furthermore, since the polyimide film can form an insulating layer together with an adhesive layer, it is possible to realize a uniform insulating layer thickness while preventing the insulating layer from becoming extremely thin.

The polyimide film of the present invention preferably has a tensile modulus of 5 GPa or more, and more preferably 6 GPa.
It is more preferably at least a. This is for imparting sufficient rigidity to the polyimide film, the laminate, and the multilayer wiring board obtained by using the laminate of the present invention.

Further, since thermal stability is required during processing of the built-up wiring board, the dimensional stability of the polyimide film is 2.0 × 10 ⁻⁵ / ° C. or less, more preferably 1.5 × 10 ⁻⁵ / ° C. / ° C or lower, more preferably 1.0 × 1
A polyimide film having a linear expansion coefficient of 0 ⁻⁵ / ° C. or less is desirable, and a polyimide film having a low water absorption is desirable so that defects such as swelling due to heat during processing do not occur. In addition, "water absorption rate" is measured according to ASTM-D570. Although the water absorption of the polyimide film depends on the thickness even with the same composition, the polyimide film having the property that the water absorption of a film having a thickness of 25 μm is preferably 1.5% or less, more preferably 1.2% or less. Is desirable.

Here, the thickness of the polyimide film of the present invention can be appropriately selected according to the application, but is specifically 5 to 300 μm, more preferably 5 to 75 μm. In order to form a small-diameter via, the thickness of the polyimide film is preferably 50 μm or less, more preferably 35 μm or less, and even more preferably 25 μm or less.

The polyimide film is obtained by imidizing a polyamic acid polymer as a precursor thereof, and the polyamic acid polymer is obtained by mixing one or more tetracarboxylic dianhydride components with one or more tetracarboxylic dianhydride components. It is obtained by polymerizing in an organic solvent using substantially equimolar kinds of diamine components or more.

Typical tetracarboxylic dianhydride components used for producing a polyimide film include pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 1,4
5,8-naphthalenetetracarboxylic dianhydride, 2,
3,6,7-naphthalenetetracarboxylic dianhydride,
4,4′-oxydiphthalic anhydride, 3,3 ′, 4
4'-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3 ', 4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 4,
4'-hexafluoroisopropylidene diphthalic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,3,3', 4'-biphenyltetracarboxylic dianhydride, p -An aromatic tetracarboxylic dianhydride such as phenylene bis (trimellitic acid monoester anhydride) and p-phenylenediphthalic anhydride.

Among these tetracarboxylic dianhydrides, a tensile modulus of 5 GPa or more and a linear expansion coefficient of 2.0 × 10
^-5 / ° C. or less, and a water absorption is preferably exemplified to obtain a polyimide film having a characteristic of 1.5% or less, based on the total amount of tetracarboxylic dianhydride,
Pyromellitic dianhydride 20-80 mol%, p-phenylenebis (trimellitic monoester anhydride) 8
A case where 0 to 20 mol% is used is exemplified. More preferably, the former is 30 to 70 mol% and the latter is 70 to 30 mol%, particularly preferably the former is 40 to 60 mol% and the latter is 6
0 to 40 mol%. In addition, the combination of the tetracarboxylic dianhydride described here shows one specific example for obtaining the polyimide film which comprises the laminated body of this invention. The characteristics of the polyimide film can be adjusted by changing the combination and the use ratio of the tetracarboxylic dianhydride to be used without being limited to these combinations.

On the other hand, as the diamine component, 4,4'-
Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2-bis (4-aminophenoxyphenyl) propane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene , 1,3-bis (3-aminophenoxy)
Benzene, bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3-aminophenoxy)
Phenyl) sulfone, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis (4-aminophenoxyphenyl) hexafluoropropane, 4,4′-
Diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 9,9-bis (4-aminophenyl) fluorene, bisaminophenoxyketone 4,
4 '-(1,4-phenylenebis (1-methylethylidene)) bisaniline, 4,4'-(1,3-phenylenebis (1-methylethylidene)) bisaniline, metaphenylenediamine, paraphenylenediamine, diaminobenz Examples thereof include aromatic diamines such as anilide, 3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, and other aliphatic diamines.

Among these diamine components, a preferable combination for obtaining a polyimide film having a tensile modulus of 5 GPa or more, a linear expansion coefficient of 2.0 × 10 ^-5 / ° C. or less, and a water absorption of 1.5% or less. For example, there is a case where paraphenylenediamine or diaminobenzanilide is used at a component ratio of 20 to 80 mol% and 4,4′-diaminodiphenyl ether is used at a component ratio of 80 to 20 mol%, based on the total amount of the diamine component. More preferably, the former is 30
The latter is 70 to 30 mol%, particularly preferably the former is 40 to 60 mol% and the latter is 60 to 40 mol%. In addition, the combination of the diamine component described here shows one specific example for obtaining the polyimide film which comprises the laminated body of this invention. The characteristics of the polyimide film can be adjusted by changing the combination and the use ratio of the diamine components to be used without being limited to these combinations.

The polyimide film of the present invention has a polyamic acid as a precursor having a weight average molecular weight of 10,000.
Desirably, it is １，1,000,000. If the weight average molecular weight is less than 10,000, the film as a product may be brittle. On the other hand, if it exceeds 1,000,000, the viscosity of the polyamic acid varnish, which is a polyimide precursor, may be too high to make handling difficult. There is.

Further, various organic additives, inorganic fillers, or various reinforcing materials are added to the polyamic acid,
It is also possible to use a composite polyimide film.

Examples of the organic polar solvent used in the reaction for producing the polyamic acid polymer include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide;
Formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide; acetamido solvents such as N, N-dimethylacetamide and N, N-diethylacetamide; N-methyl-2-pyrrolidone;
Pyrrolidone-based solvents such as vinyl-2-pyrrolidone, phenol-based solvents such as phenol, o-, m-, or p-cresol, xylenol, halogenated phenol, and catechol; or hexamethylphosphoramide, γ
-Butyrolactone, etc., and it is desirable to use them alone or as a mixture, but it is also possible to use some aromatic hydrocarbons such as xylene and toluene.

The polyamic acid polymer is contained in the organic polar solvent in an amount of 5 to 40% by weight, preferably 10 to 3% by weight.
0% by weight is desirable from the viewpoint of handling.

In order to obtain a polyimide film from the polyamic acid copolymer solution, any of a thermal method of thermally dehydrating and a chemical method using a dehydrating agent may be used. It is preferable because the resulting polyimide film has excellent mechanical properties such as elongation and tensile strength.

An example of a method for producing a polyimide film by a chemical method will be described below.

A stoichiometric or more dehydrating agent and a catalytic amount of a tertiary amine are added to the polyamic acid polymer or a solution thereof. This solution is cast or coated on a drum or an endless belt to form a film. The membrane is dried at a temperature of 150 ° C. or less for about 5 to 90 minutes to obtain a self-supporting gel film.

Here, the gel film is in an intermediate stage of curing from the polyamic acid to the polyimide, has a self-supporting property, and is calculated from the equation (1−A) × 100 / B... The volatile content is in the range of 5 to 500% by weight, preferably 5 to 100% by weight, more preferably 5 to 500% by weight.
It refers to one in the range of 50% by weight.

Further, Formula 2: imidization ratio = (C / D) × 100 / (E / F) Formula 2 In Formula 2, C: height of an absorption peak derived from an imide ring near 1370 cm ^{−1 of the} gel film D: height of an absorption peak derived from a benzene ring around 1500 cm ^{-1 of the} gel film E: height of an absorption peak derived from an imide ring around 1370 cm ^-1 of the polyimide film F: around 1500 cm ^{-1 of the} polyimide film Having an imidation ratio calculated from the height of the absorption peak derived from the benzene ring of at least 50%, preferably at least 80%, more preferably at least 85%, and most preferably at least 90%. Say. The absorbance is measured using an infrared absorption spectroscopy.

Next, this is peeled off from the support and the end is fixed. Thereafter, it is imidized by gradually heating to about 100 to 500 ° C., and after cooling, the fixing of the film end is released to obtain a polyimide film. Examples of the dehydrating agent here include aliphatic acid anhydrides such as acetic anhydride and aromatic acid anhydrides such as benzoic anhydride. Examples of the catalyst include aliphatic tertiary amines such as triethylamine, aromatic tertiary amines such as dimethylaniline, and heterocyclic tertiary amines such as pyridine, picoline and isoquinoline.

It is essential that the polyimide film of the present invention contains an electroless plating catalyst. here,
“Contains” means that the electroless plating catalyst is present on the surface and / or inside of the film. By containing the electroless plating catalyst, a step of surface roughening is not required, and it is possible to form a plating film having strong adhesion and a small surface roughness on the polyimide film surface.

Examples of the type of plating catalyst include compounds containing elements such as gold, silver, ruthenium, rhodium, palladium, osmium, iridium, and platinum. Colloidal solutions containing these elements, organic noble metal resinate solutions, various It is applied to the polyimide in the form of a metal salt solution, a solid metal salt or metal particles.

As a method for incorporating the plating catalyst into the polyimide film, these elements can be incorporated into the polyimide film at any stage of the process of producing the polyimide film, and various methods can be carried out.

For example, after mixing the above-mentioned plating catalysts of various forms into a polyamic acid solution of a polyimide precursor,
There is a method of converting polyamic acid into polyimide.

As another method for incorporating the plating catalyst into the polyimide film, a solution containing the plating catalyst, a colloid solution, or a slurry is applied to one or both sides of the gel film after the step of producing the gel film. There is a method of immersing and then heating and drying this film to imidize it to obtain a polyimide film.

In the step of applying or dipping the solution containing the catalyst or the colloid solution to the gel film,
The method of coating or dipping may be a known method that can be used by those skilled in the art.For example, a coating method using a gravure coat, spray coat, knife coat, dip coat, or the like can be used, and the workability is good. The dip coating method can be particularly preferably used from the viewpoint that the facilities are relatively simple.

A solution containing a catalyst when a compound containing a catalyst is mixed with a polyamic acid solution, a solution containing a catalyst when applied to a gel film, and a solution containing a catalyst of an immersion liquid used when immersing a gel film. Is not particularly limited. For example, water, toluene, tetrahydrofuran, 2-propanol, 1-butanol, ethyl acetate, N, N-dimethylformamide, acetylacetone and the like can be used. These solvents may be used as a mixture of two or more kinds. In the present invention,
N, N-dimethylformamide, 1-butanol, 2
-Propanol and water can be used particularly preferably.

The gel film is obtained by applying or immersing a solution of the compound containing the above-mentioned element and then removing extra drops on the film surface to obtain a polyimide film having an excellent appearance without unevenness on the film surface. It is preferable because it can be used.

Known methods such as nip rolls, air knives, doctor blades and the like can be used for removing the droplets.
Nip rolls can be preferably used.

The gel film coated or immersed in the solution containing the above element is peeled off from the support, and the ends are fixed to avoid shrinkage during curing, and dried, and water, residual solvent, residual converting agent and catalyst are removed. Is removed and the polyamic acid is converted to polyimide to obtain the polyimide film of the present invention. The drying conditions are the same as in the above-mentioned method for producing a polyimide.

According to the above method, an electroless plating catalyst can be contained on the surface and / or inside of the polyimide film. Therefore, the electroless plating catalyst can be present on the surface of the film while being mixed inside the film. Therefore, metal atoms can be firmly adhered to the polyimide film when electroless plating is performed as compared with the related art, and an electroless plating film having a small surface roughness can be formed on the polyimide film surface. .
Also, after mixing the electroless plating catalyst with the polyamic acid solution, when converting the polyamic acid to polyimide to obtain a polyimide film, and when applying or dipping the electroless plating catalyst on both surfaces of the gel film, It contains an electroless plating catalyst and can form a smooth electroless plating film with a small surface roughness that can firmly adhere to both surfaces.

In the laminate of the present invention, an adhesive layer is formed on one side of the polyimide film obtained above. Specifically, the adhesive layer is laminated on at least one surface of the polyimide film opposite to the surface on which the electroless plating catalyst is formed, and is integrated with the polyimide film. Therefore, when the laminated body of the present invention is laminated by a method such as heating press or roll heating to produce a multilayer board, the laminated body has a function of adhering to each other, whereby the inner layer circuit is embedded in the adhesive. It is firmly fixed in the form. Adhesives used for this purpose are compatible with lead-free high-melting solder generated due to environmental considerations in recent years, and with increasing substrate temperature due to the increase in conductor resistance due to the narrow pitch of circuit patterns. In consideration of the above, it is preferable that the heat resistance is high. The thickness of the adhesive layer is preferably a thickness sufficient for the circuit pattern to be embedded in the adhesive layer when the laminate of the present invention is laminated on the circuit pattern, and depends on the thickness of the conductor layer forming the circuit pattern. However, it is preferable that the adhesive layer has a thickness equal to or greater than the thickness of the conductor layer from the viewpoint of circuit embedding.

The type of the resin composition of the adhesive layer is not particularly limited as long as it satisfies the above-mentioned requirements. Many known resins can be used, and (A) a thermoplastic resin is used. The adhesive can be classified into a heat-fusible adhesive and a (B) curable adhesive utilizing a curing reaction of a thermosetting resin, and can be appropriately selected. These will be described below.

(A) Examples of the thermoplastic resin which imparts heat-fusibility to the adhesive include polyimide resin, polyamideimide resin, polyetherimide resin, polyamide resin, polyester resin, polycarbonate resin, polyketone resin, and polysulfone resin. , A polyphenylene ether resin, a polyolefin resin, a polyphenylene sulfide resin, a fluororesin, a polyarylate resin, a liquid crystal polymer resin, and the like. One or more of these may be appropriately combined and used as an adhesive layer of the laminate of the present invention. be able to. Among them, it is preferable to use a thermoplastic polyimide resin from the viewpoint of excellent heat resistance, electric reliability and the like.

Here, a method for producing a thermoplastic polyimide resin will be described. The polyimide resin is obtained from a polyamic acid polymer solution as a precursor thereof, and the polyamic acid polymer solution can be produced by a known method. That is, it is obtained by using substantially equimolar amounts of the tetracarboxylic dianhydride component and the diamine component and polymerizing in an organic polar solvent. The acid dianhydride used for this thermoplastic polyimide resin is not particularly limited as long as it is an acid dianhydride. Examples of the acid dianhydride component include butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetraanhydride Carboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 3,5,6-tricarboxynorbonane-2-acetic dianhydride Thing, two, three
4,5-tetrahydrofurantetracarboxylic dianhydride, 5- (2,5-dioxotetrahydrofural) -3
Aliphatics such as -methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, bicyclo [2,2,2] -oct-7-ene-2,3,5,6-tetracarboxylic dianhydride Or alicyclic tetracarboxylic dianhydride; pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic Acid dianhydride, 1,4,5
8-naphthalenetetracarboxylic dianhydride, 2,3
6,7-naphthalenetetracarboxylic dianhydride, 4,
4′-oxyphthalic anhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride,
3,3 ', 4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) ) Diphenyl sulfide dianhydride, 4,4
'-Bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 4,
4'-hexafluoroisopropylidene diphthalic anhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 2,3,3', 4'-biphenyltetracarboxylic dianhydride, bis (Phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4 Aromatic tetracarboxylic dianhydrides such as 2,4′-diphenyl ether dianhydride and bis (triphenylphthalic acid) -4,4′-diphenylmethane dianhydride;
Examples thereof include 2-bis (4-hydroxyphenyl) propanedibenzoate 3,3 ′, 4,4′-tetracarboxylic dianhydride. 2,2-bis (4-hydroxyphenyl) propanedibenzoate-3,3 ′, 4,4′-tetracarboxylic dianhydride, 4,4′-hexafluoroisopropylidene diphthalic anhydride, 2,3 It is preferable to use 3,3 ', 4'-biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, and 3,3', 4,4'-benzophenonetetracarboxylic dianhydride.

Further, as the diamine component, 4,4′-
Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2-bis (4-aminophenoxyphenyl) propane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene , 1,3-bis (3-aminophenoxy)
Benzene, bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3-aminophenoxy)
Phenyl) sulfone, 4,4′-bis (4-aminophenoxy) biphenyl, 2,2-bis (4-aminophenoxyphenyl) hexafluoropropane, 4,4′-
Diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, 9,9-bis (4-aminophenyl) fluorene, bisaminophenoxyketone 4,
4 '-(1,4-phenylenebis (1-methylethylidene)) bisaniline, 4,4'-(1,3-phenylenebis (1-methylethylidene)) bisaniline and the like can be mentioned, and these can be used alone. Or a combination of two or more.

Examples of the organic polar solvent used in the reaction for producing the polyamic acid solution include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide;
Formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide; acetamido solvents such as N, N-dimethylacetamide and N, N-diethylacetamide; N-methyl-2-pyrrolidone; N-vinyl- Pyrrolidone-based solvents such as 2-pyrrolidone, phenol-based solvents such as phenol, o-, m-, or p-cresol, xylenol, halogenated phenol, catechol, or hexamethylphosphoramide, γ-
Butyrolactone and the like can be mentioned. Further, if necessary, these organic polar solvents can be used in combination with an aromatic hydrocarbon such as xylene or toluene.

The polyamic acid polymer solution obtained above is dehydrated and ring-closed by a thermal or chemical method to obtain a thermoplastic polyimide resin. Any of the chemical methods used for dehydration can be used.

Examples of the method of thermally dehydrating and cyclizing the ring include a method in which the polyamic acid solution is subjected to an imidization reaction by heat treatment and, at the same time, the solvent is evaporated. Obtainable. The heating conditions are not particularly limited,
It is preferably carried out at a temperature of not more than 5 ° C. for a time period of about 5 minutes to 120 minutes.

Examples of the method of chemically dehydrating and cyclizing a ring include a method in which a dehydrating reaction and an organic solvent are evaporated by adding a dehydrating agent and a catalyst having a stoichiometric amount or more to the polyamic acid solution. Thus, a solid thermoplastic polyimide resin can be obtained.

Examples of the dehydrating agent by a chemical method include aliphatic acid anhydrides such as acetic anhydride and aromatic acid anhydrides such as benzoic anhydride. Examples of the catalyst include aliphatic tertiary amines such as triethylamine, aromatic tertiary amines such as dimethylaniline, pyridine, α-
Examples include heterocyclic tertiary amines such as picoline, β-picoline, γ-picoline, and isoquinoline. The conditions for the chemical dehydration ring closure are preferably at a temperature of 100 ° C. or less, and the evaporation of the organic solvent is performed at a temperature of 200 ° C. or less for about 5 minutes to
It is preferable to carry out within a time period of 120 minutes.

As another method for obtaining a thermoplastic polyimide resin, a thermal imidization treatment or a chemical imidization with a dehydrating agent without evaporating the solvent in the above-mentioned thermal or chemical dehydration ring closure method is used. There is a way to do the processing. The obtained polyimide resin solution is poured into a poor solvent to precipitate the polyimide resin, remove unreacted monomers, purify and dry, and obtain a solid polyimide resin. As the poor solvent, one that mixes well with the solvent but has a property that the polyimide is hardly dissolved is selected.
Examples include, but are not limited to, acetone, methanol, ethanol, isopropanol, benzene, methyl cellosolve, methyl ethyl ketone, and the like. A thermoplastic polyimide resin can be obtained by these methods, and can be used as an adhesive layer of the laminate of the present invention.

Next, (B) a curable adhesive utilizing a curing reaction of a thermosetting resin will be described. As thermosetting resins, bismaleimide resin, bisallylnadiimide resin,
Examples thereof include a phenolic resin, a cyanate resin, an epoxy resin, an acrylic resin, a methacrylic resin, a triazine resin, a hydrosilyl-cured resin, an allyl-cured resin, and an unsaturated polyester resin. These can be used alone or in an appropriate combination. Further, in addition to the thermosetting resin, a side-chain reactive group-type thermosetting resin having a reactive group such as an epoxy group, an allyl group, a vinyl group, an alkoxysilyl group, or a hydrosilyl group at a side chain or a terminal of a polymer chain. It is also possible to use molecules as thermosetting components.

Here, a side-chain reactive group type thermosetting polyimide resin having a reactive group in the side chain of the polyimide skeleton has excellent heat resistance and is preferred as the adhesive layer of the present invention. Hereinafter, the side-chain reactive group type thermosetting polyimide resin will be described.
As a specific example of the production method, it is produced by a method according to the thermoplastic polyimide resin already described, at this time, an epoxy group,
A thermosetting polyimide is obtained by using a diamine component having a functional group such as a vinyl group, an allyl group, a methacryl group, an acryl group, an alkoxysilyl group, a hydrosilyl group, a carboxyl group, a hydroxyl group, a cyano group, or an acid dianhydride component as a monomer component. Method, after producing a solvent-soluble polyimide having a hydroxyl group, a carboxyl group, an aromatic halogen group, etc. according to the thermoplastic polyimide resin manufacturing method already described, an epoxy group, a vinyl group, an allyl group, a methacryl group, an acrylic group, an alkoxy group It is also possible to obtain a thermosetting polyimide resin by a method of providing a functional group such as a silyl group, a hydrosilyl group, a carboxyl group, a hydroxyl group, a cyano group, or the like by a chemical reaction.

Further, a radical reaction initiator such as an organic peroxide, a reaction accelerator, a crosslinking aid such as triallyl cyanurate and triallyl isocyanurate, is added to the thermosetting resin.
For the purpose of improving heat resistance, adhesiveness, etc., it is also possible to appropriately add a commonly used epoxy curing agent such as an acid dianhydride type, an amine type, or an imidazole type, and various coupling agents, if necessary. is there.

It is also possible to mix (A) the thermoplastic resin with (B) a thermosetting resin for the purpose of controlling the flowability of the adhesive layer during heat bonding. In this case, it is desirable to add (B) a thermosetting resin in an amount of 1 to 10,000 parts by weight, preferably 5 to 2,000 parts by weight, based on 100 parts by weight of the thermoplastic resin (A). If the amount of the thermosetting resin is too large, the adhesive layer may be fragile. Conversely, if the amount is too small, the resin of the adhesive layer may protrude or the adhesiveness may be reduced.

Hereinafter, a specific example in which an adhesive layer is formed on the other side of the polyimide film containing the electroless plating catalyst on at least one side, but the present invention is not limited to this. . First, after dissolving a resin composition for forming an adhesive layer in a solvent to obtain a resin solution, at least one surface of the polyimide film containing the electroless plating catalyst is applied to the other surface of the polyimide film containing the catalyst and then dried. Alternatively, the resin solution obtained as above is cast on a support, the solvent is removed to form a sheet, and then the polyimide film containing the electroless plating catalyst on at least one side is coated on the other side containing the catalyst. It can also be obtained by laminating.

Further, a protective film may be used in the laminate of the present invention for the purpose of protecting the surface of the adhesive layer.

Next, an example of manufacturing a multilayer wiring board using the laminate of the present invention will be described. Providing through holes in the polyimide film of the present invention,
A metal layer, which is a conductor layer, is formed on both surfaces by electroless plating and electroplating, and a first layer circuit is further formed. The adhesive layer of the laminate of the present invention is bonded to both surfaces of the polyimide film by heat lamination or hot pressing with the adhesive layer surface of the laminate facing the conductor layer of the polyimide film. At this time, appropriate conditions are set according to the type of the adhesive layer. Next, a via hole having the land of the first layer circuit as the bottom surface is formed in the polyimide film layer containing the plating catalyst and the adhesive layer immediately above the land of the first layer circuit. As a forming method, various methods such as laser, plasma etching, chemical etching and the like can be mentioned. After forming the via hole, the via shape is adjusted by desmearing as necessary. Next, panel plating is performed by a method such as electroless plating. At this time, since the surface of the laminate of the present invention contains an electroless plating catalyst, a step of applying the catalyst is not required. By further adding a catalyst, the plating property of the via portion is improved, and good results can be obtained. Subsequently, the conductor layer formed by electroless plating is patterned and etched to form a new circuit. By repeating the above steps, a multilayer board can be obtained.

Although the polyimide film of the present invention and the laminate using the same, and the multilayer wiring board using the polyimide film and / or the laminate of the present invention have been described above, the present invention is not limited to these. Is not
Various modifications, alterations, and modifications may be made based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

[0064]

The present invention will be described below in detail with reference to examples. In the examples, ODA is 4,4'-diaminodiphenyl ether, p-PDA is paraphenylenediamine, BA
PS-M is bis (4- (3-aminophenoxy) phenyl) sulfone, DABA is 4,4′-diaminobenzanilide, PMDA is pyromellitic dianhydride, TM
HQ is p-phenylenebis (trimellitic acid monoester anhydride), ESDA is 2,2-bis (4-hydroxyphenyl) propanebenzoate 3,3 ', 4,4'
-Tetracarboxylic dianhydride, DMF represents N, N-dimethylformamide.

The method for measuring the characteristics of the polyimide film is as follows.

(Linear Expansion Coefficient) Heating and cooling from room temperature to 400 ° C. at a temperature rise / fall rate of 10 ° C./min are repeated under a nitrogen gas flow, and the average linear expansion coefficient at 100 to 200 ° C. during the second temperature increase. Was measured. As a measuring device, Rigaku Denki TM
A8140 was used.

(Tensile Modulus) The tensile modulus was determined by ASTM.
D882.

(Water Absorption) Measured according to ASTN D-570. Specifically, the weight of a film obtained by drying the film at 150 ° C. for 30 minutes was defined as W _1, and the weight of a film obtained by immersing the film in distilled water for 24 hours and then wiping off water droplets on the surface was defined as W ₂ , which was calculated by the following equation. Water absorption (%) = (W ₂ −W ₁ ) ÷ W ₁ × 100

Example 1 (1) One equivalent of DMF and p-PDA and 1 equivalent of ODA were placed in a separable flask, stirred well at room temperature until the diamine compound was completely dissolved, and then cooled with ice. Next, 1 equivalent of TMHQ was added, and the mixture was cooled and stirred for 40 minutes. Then, 1 equivalent of PMDA was dissolved in DMF, gradually added, and then cooled and stirred for 1 hour to obtain a polyamic acid DMF solution. The amount of DMF used is such that the concentration of the charged monomers of the diamino compound and the aromatic tetracarboxylic acid compound is 18%.
% By weight.

For 100 g of the above polyamic acid solution,
After adding 10 g of acetic anhydride and 10 g of isoquinoline and uniformly stirring, degassing is performed, and the mixture is cast and applied on a glass plate.
After drying at 00 ° C. for about 10 minutes, the polyamic acid coating film was peeled off from the glass plate to obtain a gel film.

An organic noble metal resinate compound (trade name: Pd-C8, DMSC Square-
-Japan Co., Ltd.) was diluted with DMF so that the Pd concentration became 0.05%, and applied uniformly. Two types were prepared, one coated on both sides of a gel film and one coated on a gel film.

Next, this coating film was fixed to a support frame, and then at about 200 ° C. for about 10 minutes, at about 300 ° C. for about 10 minutes, and for about 4 minutes.
Heated at 00 ° C. for about 10 minutes, about 500 ° C. for about 10 minutes,
The polyimide film according to the present invention having a thickness of about 25 μm having an electroless plating catalyst on one side and both sides was obtained by dehydration ring-closing and drying. The resulting polyimide film has a tensile modulus of 6 GPa, a water absorption of 1.2%, and a coefficient of linear expansion of 1.
It was 0 × 10 ⁻⁵ / ° C. In addition, electroless plating was performed according to a conventional method, and the adhesive strength at the polyimide film / copper foil interface was measured. As a result, it was 10 N / cm.

(2) DMF and B in a separable flask
One equivalent of APS-M was taken, stirred well at room temperature until BAPS-M was completely dissolved, and then cooled with ice. Next, 1 equivalent of ESDA was added, and the mixture was stirred with cooling for 1 hour to obtain a polyamic acid DMF solution. The amount of DMF used was such that the monomer charge concentration of the diamino compound and the aromatic tetracarboxylic acid compound was 30% by weight. 35 g of β-picoline and 60 g of acetic anhydride were added to 500 g of this polyamic acid solution, and the mixture was stirred for 1 hour.
For 1 hour and imidized. Thereafter, this solution was gradually added to methanol stirred at a high speed to obtain a thread-like polyimide resin. After drying at 100 ° C. for 30 minutes, the mixture is pulverized by a mixer, washed with Soxhlet with methanol,
It was dried at 100 ° C. for 2 hours to obtain a polyimide powder.

(3) 20 g of the polyimide powder obtained above,
Bisphenol A epoxy resin; Epicoat 828
(Manufactured by Yuka Shell Co., Ltd.) 5 g, 0.01 g of 2-ethyl-4-methylimidazole as a hardening accelerator and 83 g of DMF
Was dissolved. The obtained varnish was cast on a glass plate,
After drying at 00 ° C. for 10 minutes, the film was peeled off from the glass plate, the coating film was fixed on a support frame, and further dried at about 150 ° C. for about 20 minutes to obtain an adhesive sheet having a thickness of 25 μm.

(4) The surface of the polyimide film obtained in (2) without the electroless plating catalyst was brought into contact with the adhesive sheet obtained in (3), and heated at a temperature of 200 ° C. and a pressure of 3 MPa for 20 minutes. The laminate of the present invention was obtained.

(5) Production of Multilayer Wiring Board A metal layer, which is a conductor layer, is formed on both sides of the above-obtained polyimide film coated with a catalyst on both sides, and a first-layer circuit is formed. On both surfaces of the polyimide film, the adhesive layer surface of the obtained laminate of the present invention was opposed to the conductor layer of the polyimide film.
The bonding was performed under the conditions of 2 hours of MPa. Next, a via hole having a land of the first layer circuit as a bottom surface was formed by laser. After the desmear treatment, the reaction was performed at 55 ° C. for 20 minutes using Copper LP manufactured by Okuno Pharmaceutical Co., Ltd. Subsequently, while a current of ² A / dm ² was applied by electrolytic plating, the thickness of the conductor was reduced to 1
Electrolytic copper plating was performed until the thickness became 8 μm. The conductor layer is patterned and then etched to form a new circuit. As described above, a very thin four-layer wiring board having a total thickness of 125 μm and a uniform thickness between the respective layers was obtained.

(Example 2) Organic noble metal resinate compound
After the Pd concentration of (Pd-C8) was 0.01%
Outside, a polyimide film was obtained in the same manner as in Example 1. Profit
The polyimide film obtained has a tensile modulus of 6 GPa,
Water content is 1.2%, coefficient of linear expansion is 1.0 × 10 ^-Five/ ℃
Was. Also, perform electroless plating in accordance with
When the adhesive strength at the interface between the film and the copper foil was measured, it was 7
N / cm. A laminate was manufactured in the same manner as in Example 1.
Very thin with a total thickness of 125 μm
A four-layer wiring board having a uniform thickness between layers was obtained.

Example 3 A polyimide film was obtained in the same manner as in Example 1, except that the Pd concentration of the organic noble metal resinate compound (trade name: Pd-C8) was 0.2%. The resulting polyimide film had a tensile modulus of 6 GPa, a water absorption of 1.2%, and a coefficient of linear expansion of 1.0 × 10 ⁻⁵ / ° C. In addition, electroless plating was performed according to a conventional method, and the adhesive strength at the polyimide film / copper foil interface was measured.
/ Cm. In the same manner as in Example 1, a laminated body was manufactured, and a very thin four-layer wiring board having a total thickness of 125 μm and a uniform thickness between the layers was obtained.

Example 4 DMF was placed in a separable flask.
And 1 equivalent of ODA, stirred well at room temperature until completely dissolved, and then cooled with ice water. Next, 2 equivalents of TMHQ was added, and the mixture was stirred with cooling for 1 hour. Subsequently, 1 equivalent of DABA was added, and the mixture was stirred with cooling for 1 hour to obtain a polyamic acid DMF solution. The amount of DMF used was such that the monomer charge concentration of the diamino compound and the aromatic tetracarboxylic acid compound was 18% by weight.

From the above polyamic acid, an organic noble metal resinate compound was adjusted to a Pd concentration of 0.05% and applied in the same manner as in Example 1 to obtain a polyimide film. The obtained polyimide film had a tensile modulus of 10 GPa, a water absorption of 0.8%, and a coefficient of linear expansion of 0.6 × 10 ⁻⁵ / ° C. In addition, electroless plating was performed according to a conventional method, and the adhesive strength at the polyimide film / copper foil interface was measured.
/ Cm. In the same manner as in Example 1, a laminated body was manufactured, and a very thin four-layer wiring board having a total thickness of 125 μm and a uniform thickness between the layers was obtained.

Example 5 A polyimide film was obtained in the same manner as in Example 4, except that the Pd concentration of the organic noble metal resinate compound (trade name: Pd-C8) was 0.01%. Tensile modulus of the obtained polyimide film is 10 GPa,
The water absorption was 0.8%, and the coefficient of linear expansion was 0.6 × 10 ⁻⁵ / ° C. In addition, electroless plating was performed according to a conventional method, and the adhesion strength of the polyimide film / copper foil interface was measured.
It was 7 N / cm. A laminate was manufactured in the same manner as in Example 1, and the laminate was made extremely thin with a total thickness of 125 μm.
A four-layer wiring board having a uniform thickness between the layers was obtained.

Example 6 Organic Noble Metal Resinate Compound
Except that the Pd concentration of (trade name Pd-C8) was 0.2%
In the same manner as in Example 4, a polyimide film was obtained. Get
The tensile modulus of the polyimide film obtained was 10 GPa,
Water content is 0.8%, coefficient of linear expansion is 0.6 × 10 ^-Five/ ℃
Was. Also, perform electroless plating in accordance with
When the adhesive strength at the interface between the film and the copper foil was measured, it was 8
N / cm. A laminate was manufactured in the same manner as in Example 1.
Very thin with a total thickness of 125 μm
A four-layer wiring board having a uniform thickness between layers was obtained.

[0083]

Industrial Applicability The polyimide film and laminate of the present invention can be widely used for producing multilayer wiring boards,
Electroless plating can be performed without surface roughening and the like, and a metal layer can be firmly adhered and a smooth electroless plating film with small surface roughness can be obtained. This allows
A multilayer wiring board having high heat resistance, a narrow pitch wiring pattern, a small-diameter via, a uniform insulating layer thickness, a moderately low coefficient of linear expansion, and suitable for a high-frequency circuit can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08J 7/06 CFG C08J 7/06 CFGZ H05K 3/38 H05K 3/38 A 3/46 3/46 T / / C08L 79:08 C08L 79:08 F term (reference) 4F006 AA39 AB73 BA01 CA08 4F071 AA60 AB06 AB07 AF10 AF20 AF62 AH13 BB02 BC01 4F100 AB01B AB01C AB24B AB24C AB25B AB25C AH08 AK01D AK49 BA10 BA10 BA10 BA10 BA07 EH46 EH46B EH46C EH71B EH71C EJ42 GB43 JA02 JA20 JB13D JD15 JJ03 JK06 JK07 JL08B JL08C JL11D YY00 5E343 AA02 AA07 AA18 BB24 BB67 CC72 CC73 DD43 GG02 GG11 5E346 AA12 CC10 DD11

Claims (10)

[Claims] 1. A polyimide film containing an electroless plating catalyst, which is produced by mixing an electroless plating catalyst in a step of producing a polyamic acid as a precursor. 2. It is manufactured by applying or dipping an electroless plating catalyst in a gel film state.
A polyimide film containing an electroless plating catalyst. 3. The polyimide film according to claim 1, which has a tensile modulus of 5 GPa or more. 4. The polyimide film according to claim 1, which has a coefficient of linear expansion of 2.0 × 10 ⁻⁵ / ° C. or less. 5. The polyimide film according to claim 1, which has a water absorption of 1.5% or less. 6. The electroless plating catalyst according to claim 1, wherein the electroless plating catalyst contains at least one element selected from gold, silver, ruthenium, rhodium, palladium, osmium, iridium, and platinum. The polyimide film according to the above. 7. A laminate comprising the polyimide film according to claim 1 and an adhesive layer formed on one surface of the laminate. 8. A laminate comprising the polyimide film according to any one of claims 1 to 6 containing an electroless plating catalyst on one surface and an adhesive layer on the other surface. 9. The laminate according to claim 7, wherein the adhesive layer is made of a resin composition containing a thermosetting resin. 10. A multilayer wiring board using the polyimide film according to any one of claims 1 to 6 and / or the laminate according to any one of claims 7 to 9.