JP2888269B2 - Polymer composite and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polymer composite and a method for producing the same. In particular, the present invention relates to a composite of polyimide having excellent heat resistance and widely used in the fields of electronics, transportation equipment, aerospace, and the like, and an existing acrylic resin component or phosphazene resin component. In addition, it has the heat resistance, insulation, and toughness characteristics of polyimide resins including polyimide engineering plastics, and has low stress (stress).
An object of the present invention is to provide a heat-resistant insulating film such as a protective film and an interlayer insulating film of a printed board, a wiring board and an electronic component.

[0002]

2. Description of the Related Art Polyamic acid obtained by polycondensation of a tetracarboxylic dianhydride and an aromatic diamine in an organic solvent is used as a precursor, and dehydration and ring closure are performed by heat dehydration or a chemical reaction with a dehydrating agent to obtain a polyimide. Methods for obtaining resins are known. Polyimide resin has excellent heat resistance, abrasion resistance, chemical resistance, electrical insulation, and mechanical properties.
Widely used for electronic materials, adhesives, paints, composite materials, fiber or film materials, and the like.

Generally, the polymerization of polyamic acid, which is a precursor of a polyimide resin, is carried out at a polymer concentration of 5 to 20% by weight.
The reaction is carried out by a polyaddition reaction between a tetracarboxylic dianhydride and an aromatic diamine in an organic solvent so as to obtain a high-molecular-weight polyamic acid solution uniformly dissolved in the organic solvent. By removing the solvent from the polyamic acid solution, a film or molded product is obtained. Further, it is a usual method to perform a dehydration / ring-closure reaction on the molded body by a high temperature treatment or a chemical treatment to obtain a polyimide molded body.

[0004] Blends obtained by mixing a curable resin component with polyimide are disclosed in JP-A-62-30122, JP-A-63-86746, JP-A-63-175854, and the like. The technique is known. The purpose of the technique is mainly to improve heat resistance and moldability. However, by combining a monomer or oligomer of an existing acrylic resin component or phosphazene resin component with polyamic acid, which is a precursor of polyimide achieved by a specific monomer composition and process, a polymer composite having a unique sea-island structure After the monomer or oligomer of the uncured acrylic resin component or phosphazene resin component is made high molecular weight by means of heat, light or electron beam, the polyamic acid component is imidized by a dehydration / ring closing reaction. No report has been made on a novel polyimide-based polymer blend obtained by completing the above process and a method for producing the same.

Conventionally, a polyimide resin containing a polyimide-based engineering plastic has been used for a heat-resistant insulating film such as a protective film and an interlayer insulating film of printed circuits, printed boards, wiring boards and electronic components for high-density mounting. Was. Polyimide resins have long been recognized as having significant benefits in improving the performance characteristics of integrated circuit (IC) devices because organic polymer insulators have a lower dielectric constant than commonly used inorganic materials. It has been a material that has provided potential benefits as passivation and interlayer dielectrics in microelectronics. In high-density integrated circuits, rapid signaling and low crosstalk levels are among several important considerations, and thus typically have a dielectric constant of 3.5 and many excellent thermal Polyimide insulators exhibiting mechanical properties are preferred over inorganic dielectrics.

In electronic devices such as semiconductor devices, a polyimide resin is used as a protective film for maintaining the function of the device or as an interlayer insulating film for insulating between layers of multilayer wiring. Since the thermal expansion coefficients of the base material and the wiring material such as aluminum and the passivation material such as SiO ₂ are greatly different, warping of the wafer and generation of chip cracks may occur depending on the thickness of the polyimide film to be formed and the element structure. was there. As a method of alleviating these, studies are being made to make the thermal expansion coefficient of the polyimide resin close to that of the silicon substrate. For example, with respect to polyimide having low thermal expansion (low TCE), JP-A-4-224824 discloses
U.S. Pat. No. 4,690,999; IEEE Transactions on Electron Devices, ED-34 such as Misawa
Many inventions have been published, such as Vol. 3, No. 3, March 1987. However, even when the polyimide having a low coefficient of thermal expansion has a large thickness, or when the polyimide having a low coefficient of thermal expansion is made to be photosensitive, the warp of the wafer often increases.

In the recently developed photosensitive polyimide, especially in the post-baking for imidization at the end, a photosensitive group having a large molecular weight is volatilized in addition to water as a by-product, so that the film reduction is about 50% or more. However, there is a problem that the stress is larger than that of the non-photosensitive material (FIG. 8). In FIG. 8, 1 is a substrate, 2 is a photosensitive polyimide, and 3 is a mask.

[0008]

Therefore, the first aspect of the present invention
The purpose is to obtain a polymer gel obtained by combining a polyamic acid composed mainly of tetracarboxylic dianhydride, aromatic diamine and polyamine and an uncured curable resin component. Dehydration and ring closure of the polyamic acid component following the curing reaction of the reactive resin component to control the polymer complex (polymer blend) having a new sea-island structure with excellent low stress and the size of the island An object of the present invention is to provide a manufacturing method which can be performed.

A second object of the present invention is to provide a low stress polyimide-based insulating film.

[0010]

According to the present invention, in order to achieve the above object, a polyimide resin and a curable resin obtained by using a tetracarboxylic dianhydride, an aromatic diamine and a polyvalent amine as main components are composed of sea-island. to name the structure, form a sea of surface
Rough surface due to removal of polyimide resin or curable resin
The present invention provides a polymer complex characterized in that the polymer complex is formed. Similarly, the present invention provides a specific solution from a composite solution of a polyamic acid mainly composed of tetracarboxylic dianhydride, aromatic diamine and polyamine and an uncured curable resin.
By evaporating the solvent, a sea-island structure is formed between the polyamic acid and the uncured curable resin, and then the curable resin is cured, and the polyamic acid is dehydrated and closed to form a polyimide resin. And a method for producing a polymer composite, wherein a sea-island structure of a curable resin and a polyimide resin is formed.

A first feature of the present invention is that a mixed solution of a polyamic acid containing tetracarboxylic dianhydride, an aromatic diamine and a polyamine as a main component, and an uncured acrylic resin or the like is used. If the solvent is evaporated by maintaining the temperature at a predetermined temperature or the like, the compatibility between the polyamic acid and the curable resin component is poor, so that the sea-island structure of the polyamic acid and the curable resin component, particularly It has been found that an islands-in-sea structure having the curable resin component as an island is obtained, and that the islands-in-sea structure is maintained even after the curing of the curable resin component and the dehydration and ring closure reaction of the polyamic acid.

In addition, since the phase of the curable resin component forming an island in this sea-island structure becomes smaller as the temperature and time of heating (evaporation) increase, it has been found that the size of the island can be arbitrarily adjusted. Was. The second feature of the present invention is that, after forming a sea-island structure in which a polyamic acid is an ocean and a curable resin component is an island, the curable resin is cured, and then the polyamic acid on the surface is selectively dissolved. When the curable resin forming the island is exposed, irregularities can be formed on the surface, and the irregularities can be maintained even after dehydration and ring closure of the polyamic acid. The unevenness (rough surface) is effective, for example, in improving the adhesion of a conductive layer formed on the insulating layer when the polyimide-based composite resin is used as an insulating layer of a semiconductor device or the like.

A third feature of the present invention is that after forming a sea-island structure in which polyamic acid is used as the sea and the curable resin is used as the island,
After curing the uncured curable resin component in the selected region, and then dissolving the polyamic acid and the uncured curable resin component, the polyamic acid and the uncured curable resin other than the selected region, that is, the unselected region. Since the components are selectively dissolved, the cured curable resin and the polyamic acid in the selected region remain selectively, that is, a pattern can be formed, and thus, when the remaining polyamic acid is dehydrated and ring-closed, the polyimide resin and A composite resin pattern composed of a curable resin is obtained, and selective curing of the curable resin component can be performed by exposure.

The polymer composite (polymer blend) of the present invention is prepared by the following method. (1) A polyamic acid solution uniformly dissolved in an organic solvent is obtained by mixing a tetracarboxylic dianhydride, an aromatic diamine, and a polyvalent amine in an organic solvent and performing a polyaddition reaction.

(2) A resin or a resin composition containing a reactive monomer or oligomer as an uncured resin component as a main component and, if necessary, a reaction initiator are combined with the above-mentioned polyamic acid solution. In this case, a polyamic acid polyaddition reaction is performed in a solution containing an uncured curable resin component in an organic solvent in advance, or a gelled polyamic acid solution obtained by the polyaddition reaction, The uncured curable resin component and the polyamic acid are compounded by a method such as adding an uncured curable resin component.

(3) The mixed solution obtained by combining the polyamic acid solution and the uncured curable resin component is cast or molded on a substrate or the like in order to form a film or the like before curing. Inject into mold. (4) The organic solvent is removed from a polyamic acid polymer gel containing an organic solvent and an uncured curable resin component to obtain a molded article. By controlling the removal of the solvent, the sea-island structure is obtained.

(5) Following the curing reaction of the uncured curable resin component constituting the molded article, the dehydration and ring closure reaction of the polyamic acid component is completed to obtain a polymer composite (polymer blend). Hereinafter, the adjustment method will be described in detail. In the polyaddition reaction of tetracarboxylic dianhydride, aromatic diamine and polyamine, this reaction is, after all, a reaction between tetracarboxylic dianhydride and amines. Under such an inert atmosphere, tetracarboxylic dianhydride may be added to a solution in which an aromatic diamine and a polyvalent amine are dissolved in an organic solvent. The tetracarboxylic dianhydride may be added in a solid form or in a liquid form dissolved in a solvent. A method of adding an aromatic diamine and a polyamine to the tetracarboxylic dianhydride may be used.

Representative examples of the tetracarboxylic dianhydride used in the present invention include pyromellitic dianhydride, 3,
3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 2,2', 6,6-biphenyltetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride Anhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,2-bis (3
4-dicarboxylphenyl) propane dianhydride, bis (3,4-dicarboxylphenyl) sulfone dianhydride, bis (3,4-dicarboxylphenyl) ether dianhydride, 3,4,9,10-perylene Tetracarboxylic dianhydride, naphthalene-1,2,4,5-tetracarboxylic dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, benzene-1,2,3,4 -Tetracarboxylic dianhydride, ethylene glycol bis (anhydrotrimellitate) and the like, which can be used alone or in a mixture of two or more.

Among these, it is preferable to use pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride alone or as a mixture of two or more of them as the tetracarboxylic dianhydride. This is preferable for obtaining a polyimide composite having high properties and excellent mechanical properties. Representative examples of aromatic diamines to be reacted with tetracarboxylic dianhydride include metaphenylenediamine, paraphenylenediamine, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane , 4,4'-
Diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 4,
4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'diaminodiphenyl ether, 4,4'-diaminobenzophenone, 3,3 '
-Diaminobenzophenone, 2,2'-bis (4-aminophenyl) propane, benzidine, 3,3'-diaminobiphenyl, 2,6-diaminopyridine, 2,5-diaminopyridine, 3,4-diaminopyridine, bis [4
-(4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone,
Bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, 2,2'-bis [4- (4-aminophenoxy) phenyl] propane, 2,2 '-Bis [4- (3-
Aminophenoxy) phenyl] propane, 4,4'-bis (4-aminophenoxy) biphenyl, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4
-Aminophenoxy) benzene, 2,2'-bis [4-
(3-aminophenoxy) phenyl] hexafluoropropane, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene and derivatives thereof. Also,
Dihydrazide compounds such as dihydrazine isophthalate can also be used. These can be used alone or in a mixture of two or more.

Among them, the use of a single or a mixture of two or more of metaphenylenediamine, paraphenylenediamine, diaminodiphenylmethane, and diaminodiphenylether as the aromatic diamine makes it possible to obtain a polyimide composite having high heat resistance and excellent mechanical properties. It is preferable for obtaining body. The polyamine refers to a compound having three or more amine groups and / or ammonium bases in one molecular structure.

Representative examples of polyvalent amines include 3,3 ',
4,4'-tetraaminodiphenyl ether, 3,
3 ', 4,4'-tetraaminodiphenylmethane, 3,
3 ', 4,4'-tetraaminobenzophenone, 3,
3 ', 4,4'-tetraaminodiphenyl sulfone,
3,3 ', 4,4'-tetraaminobiphenyl, 1,
2,4,5-tetraaminobenzene, 3,3 ', 4-triaminodiphenyl ether, 3,3', 4-triaminodiphenylmethane, 3,3 ', 4-triaminobenzophenone, 3,3', 4- Triaminodiphenyl sulfone, 3,3 ', 4-triaminobiphenyl, triaminobenzene and compounds in which the functional group of these compounds is changed to a quaternary ammonium salt, for example, 3,3', 4
4'-tetraaminobiphenyl tetrahydrochloride and the like. The quaternary ammonium salt can be used in the form of sulfate or nitrate in addition to hydrochloride. Some of these compounds include those in which all of the functional groups of the polyamine are not in the form of a quaternary ammonium salt. Some of the above substances exist as hydrates, and these polyamines can be used alone or as a mixture of two or more kinds. It is also possible to use aliphatic polyvalent amines.

The organic solvent used in the reaction for obtaining the polyamic acid containing tetracarboxylic dianhydride, aromatic diamine and polyamine as the main components is inert to the reaction, and at the same time, the monomers and It is necessary to dissolve the polymerized high molecular weight substance, and typical examples are N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N, N
-Diethylacetamide, dimethylsulfoxide, N-
Phenols such as methyl-2-pyrrolidone, N, N-dimethylmethoxyacetamide, hexamethylphosphamide, pyridine, dimethyl sulfone, tetramethylene sulfone, cresol, phenol, xylenol, benzene, toluene, xylene, benzonitrile, dioxane, Cyclohexane and the like. These solvents are used alone or in combination of two or more.

The molar ratio of tetracarboxylic dianhydride / polyamine to be reacted is preferably (100) / (2 to 25), particularly preferably (100) / (4 to 25).
Although it is the range of 15), the preferable composition range may be slightly shifted depending on the type of the monomer used. Since these tetracarboxylic dianhydrides, aromatic diamines and polyamine components are used alone or in a mixture of two or more, the resulting polymers include those of copolymers. Further, a blend of a polyamic acid in which a polyamic acid composed of a specific component and a polyamic acid in which at least one of the components of the polyamic acid is different is also included.

The uncured curable resin component complexed with the polyamic acid component is a resin or a resin composition containing at least a reactive monomer and / or a reactive oligomer soluble in an organic solvent. Examples of the type of the resin component include a thermosetting resin, a photocurable resin, and an electron beam curable resin, and these can be used alone or as a mixture of two or more. Particularly preferred are uncured acrylic resin components and phosphazene resin components,
Reactive monomers and / or reactive oligomers having at least two unsaturated double bonds are preferred. These often contain a reaction initiator and a curing accelerator in addition to the resin component as the resin composition.

Typical solvents for dissolving the uncured curable resin during mixing are amide solvents such as N, N-dimethylformamide and N, N-dimethylacetamide, cresol, phenol, and the like. Phenols such as xylenol, dimethyl sulfone, tetramethylene sulfone, sulfone solvents such as dimethyl sulfoxide,
Hydrocarbons such as benzene, toluene, xylene and cyclohexane, chlorinated solvents such as methylene chloride and dichloroethane, ketones, alcohols, N-methyl-2-pyrrolidone, benzonitrile, pyridine, dioxane, polyphosphoric acid, N, N -Dimethylaniline and the like. These solvents are used alone or in combination of two or more.

By the above operation, a mixed solution of the polyamic acid uniformly dissolved in the organic solvent and the uncured curable resin component is obtained. This mixed solution is applied to a substrate such as a silicon wafer by a spin coating method, a roll coating method, a dip coating method, or the like, for about 30 to
By maintaining the temperature at 200 ° C., it has been found that when the solvent of the mixed solution is evaporated, phase separation occurs, and a sea-island structure can be formed. In this state, after the uncured curable resin component that is an island is cured, a resin having a sea-island structure, that is, a polymer blend is obtained by subsequently performing a dehydration and ring-closing reaction of the polyamic component that is a sea. be able to. The fact that the island is a curable resin component and the sea is a polyimide was clarified by component analysis after curing. Furthermore, it became clear that the particle diameter of the island became smaller as the drying progressed during the solvent drying, and it became possible to control the particle diameter of the island.

First, the solvent is dried by applying heat to the uniformly mixed solution after application. As the solvent dries, the compatibility of the mixed solution of the uniformly dissolved polyamic acid and the uncured curable resin component decreases. When the compatibility decreases, a sea-island structure unique to the mixed resin (polymer blend) is formed. At this time, the curable resin component is soft, and the volume occupied by the mixed solution of the polyamic acid containing the solvent is large, so that the polyamic acid becomes a sea while imidization proceeds, and the curable resin becomes hard. The component is an island. Further, as the volume occupied by the polyamic acid decreases, the soft curable resin component is gradually crushed into small islands. However, when the curable resin component is cured by light or heat in the middle, the size of the island is fixed at that time, and even if heating is further performed, only the progress of imidization proceeds, and the island does not become smaller.

When the above-mentioned solvent contained in the polyamic acid is gradually heated at a temperature lower than the boiling point of the solvent,
At the time of mixing, the curable resin temporarily dissolved cannot be dissolved, and starts to separate to cause phase separation. Here, it was found that the heating temperature was preferably from 30 ° C. to 200 ° C. and the heating time was preferably from 5 minutes to 3 hours, depending on the type, boiling point or film thickness of the solvent. FIGS. 1A and 1B show a structure obtained by heating a polyamic acid and an acrylic resin monomer at 60 ° C. and 120 ° C. for 60 minutes, respectively, wherein the polyamic acid (polyimide) is the sea, and the acrylic resin monomer is the island. Cross section SEM of
Although it is a photograph, it is recognized that the particle size of the island is smaller at 120 ° C. than at 60 ° C.

When such a polymer blend film is used, a decrease in volume due to imidization peculiar to polyimide can be mitigated, so that a film having a lower stress than a normal polyimide film can be obtained. In addition, as will be described later in Examples, by washing (developing) with a solvent capable of dissolving the polyamic acid before complete imidization of the polyimide, the polyamic acid which is the outermost sea can be removed. Fine irregularities are formed depending on the sea-island structure. The unevenness on the film surface makes it possible, for example, to increase the adhesion of the film by the anchor effect when the next film is formed thereon.

FIG. 2 shows an enlarged photograph of the polymer blend film having the surface irregularities. It is recognized that the acrylic resin island is exposed on the surface. In FIG. 2, the amount of the acrylic resin monomer is twice as large in (B) as in (A), but it is recognized that the particle size of the acrylic island is large. In addition, the present inventors have studied a method of relieving the stress of a polyimide resin that shrinks during curing and has a large volume change, and as a result, has found that it is better to disperse particles having a small volume change due to heat in a film. Was.
In FIG. 3, 1 is a substrate, 2 is a polyimide resin, and 5 is fine particles.

Specifically, as the particles whose volume change due to heat is small, in the case of organic substances, acrylic or phosphazene-based particles whose volume change due to heat is small are uniformly dispersed in the polyimide resin film. As a method of uniformly dispersing, there is a method in which acrylic or phosphazene-based fine particles are prepared in advance, dispersed in a precursor varnish of a polyimide resin, and imidized as a film.

In order to uniformly disperse the fine particles in the composition, a method such as high-speed stirring with a homomixer or ultrasonic dispersion can be used as necessary. Alternatively, a method of mixing a suspension in which fine particles are dispersed in a solvent in advance may be used. The material relating to low stress of the present invention has no problem even if inorganic or organic fine particles are used in combination, and the effect is large.

Further, in connection with the above, when an acrylic or phosphazene monomer is dissolved in a polyimide resin precursor varnish to form a film, and the solvent contained in the varnish is dried, Micro phase separation occurs, and the acrylic- or phosphazene-based monomer and the precursor of the polyimide-based resin have a “sea-island structure”. At this time, the monomer becomes an “island”. When the monomer phase-separated into "sea islands" is cured by heat or light irradiation, acrylic or phosphazene-based polymer fine particles are dispersed in the polyimide-based resin film serving as a matrix. A film is formed.

The polyimide film used in this embodiment of the present invention is not limited to the above-mentioned polyimide film of the polymer composite, but also selectively combines tetracarboxylic acid and diamine and reacts them in a polar solvent to obtain a polyimide film. After forming the varnish of the precursor, the varnish of the polyimide precursor can be obtained by applying the varnish of the polyimide precursor on a substrate, performing heat treatment at a temperature in the range of 200 to 400 ° C., and performing dehydration condensation, and a known polyimide film can be used.

Specifically, pyromellitic dianhydride and 4,4'-diaminodiphenyl ether, 3,3 ',
4,4'-benzophenonetetracarboxylic dianhydride and 4,4'-diaminodiphenyl ether, 3,3 ',
4,4'-biphenyltetracarboxylic dianhydride and 4,4
4'-diaminodiphenyl ether, pyromellitic dianhydride and paraphenylenediamine, 3,3 ', 4,4'
Polyimide synthesized from -biphenyltetracarboxylic dianhydride, paraphenylenediamine, bis (3-aminopropyl) tetramethyldisiloxane, or the like is preferably used, but is not limited thereto.

The particle size of the fine particles is not particularly limited, but is preferably 5 μm or less, more preferably 2 μm or less.
In order to obtain a flat thin film, the particle diameter of the fine particles is preferably small. The shape may be not only spherical but also flake. As described above, a film in which fine particles are uniformly dispersed in this way, after a polyimide-based precursor is applied as a coating, imidation starts by heat to generate by-products, and the solvent is dried. It has been found that when the volume shrinkage occurs in some cases, the fine particles have an action of preventing the volume shrinkage and causing the stress to be reduced, so that the stress is alleviated more than the film containing no fine particles.

By dispersing fine particles at a ratio of 1: 1 with respect to the resin content of the polyimide-based precursor varnish, a stress of 70% or less for non-photosensitive polyimide and 60% for photosensitive polyimide. % Or less, and it is possible to suppress the warpage of the wafer and the disconnection of the wiring layer in the thin film multilayer circuit. Conventional photosensitive polyimides usually have a stress of 40 MPa or more, and non-photosensitive polyimides usually have a stress of 35 MPa or more. Therefore, protective films and interlayers for printed circuits, printed boards, wiring boards and electronic components for high-density mounting. 10 to 2 for use as insulating film, etc.
When two or more insulating films each having a thickness of 0 μm are laminated, a thickness of 500
Although a wafer having a thickness of about μm may be warped and a disconnection often occurs in a wiring layer, the use of the material of the present invention makes it possible to suppress the stress to about 25 MPa while maintaining the characteristics of polyimide. It can be sufficiently applied to a thin film circuit having more than two layers.

[0038]

Embodiments of the present invention will be described below. Example 1 A polyamic acid solution was prepared by the following process. 30
In a 0 ml four-neck separable flask, 0.45 g of purified paraphenylenediamine (abbreviation: PPD) was added.
16 g of 3,3 ', 4,4'-tetraaminobiphenyl tetrahydrochloride dihydrate (abbreviation: TABT) was collected and collected.
0 g of distilled N-methyl-2-pyrrolidone (abbreviation:
NMP) was added and stirred to dissolve.

Under a nitrogen atmosphere, the temperature of the external water tank was controlled at 5 ° C., and 1.6 g of purified 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride (abbreviated name) was stirred with the above solution. : BTDA) is added as it is while adding solid while paying attention not to raise the temperature of the solution.
After all the additions have been completed, stirring is continued to perform a polyaddition reaction, and a uniform polyamic acid solution (polyimide precursor varnish)
Was adjusted. This polyimide precursor varnish was added to 100.0
25.0 g of tris (acryloyloxyethyl) isocyanate was added as an acrylic monomer in 3.0 g, and 3.0 g of 2,2-dimethoxy-2-phenylacetophenone was further added as a photoreaction initiator.

This photosensitive solution was subjected to a pretreatment of 3 inches for S
After spin-coating on the i-wafer, it was heated at 100 ° C. lower than the boiling point of the varnish solvent N-methyl-2-pyrrolidone (boiling point 204 ° C.) for 1 hour, and the N-
Slow evaporation of methyl-2-pyrrolidone provided the "sea-island structure" as follows. A glass mask was placed on this dry plate, and the exposure amount was 300 mJ / cm ² using an ultraviolet exposure machine.
(365 nm) to cure the acrylic monomer: tris (acryloyloxyethyl) isocyanate.

Next, the substrate was subjected to ultrasonic immersion development with an N-methyl-2-pyrrolidone solution, followed by rinsing with isopropyl alcohol, whereby only the irradiated pattern region remained, and the unirradiated region was eluted. Finally, post-baking was performed at 300 ° C. for 30 minutes in order to convert the remaining polyimide precursor into a polyimide resin. The film thickness after post-baking was 10 μm.

When this film was observed with a scanning electron microscope (SEM), "sea-island structure" was observed, and fine irregularities were formed on the film surface (FIG.
FIG. 2A shows the surface of the via hole. In the cross-sectional photograph of FIG. 4, an acrylic island has partially dropped off from the cross section. FIG.
As shown in the above, when the “sea” and “island” were analyzed using FT-IR, absorption specific to acrylic was observed from the “island” (fine particles), so that the “sea” (matrix) was polyimide and “island”. Was found to be acrylic. From this, it was found that acrylic polymer fine particles of about 1 to 2 μm were dispersed in the polyimide resin film as the matrix.

Example 2 The photosensitive solution used in Example 1 was spin-coated on a 3-inch pre-processed Si wafer, and the solvent evaporation temperature was changed to 30 ° C., 60 ° C., 90 ° C., and 120 ° C., respectively. The sample was solidified with liquid nitrogen at a pre-bake time of 30 minutes at ℃, and the cut cross section was taken with an environmental scanning electron microscope (E-
(SEM).

Since the sample at 30 ° C. contained a large amount of solvent, the film thickness was 24 μm.
The islands were separated into islands, and the size of the islands was as large as about 10 μm. In the case of the sample at 60 ° C., the film thickness was slightly reduced, and the “island” having a film thickness of 20 μm was observed to be small and separated, and the average size was about 8 μm.

In the sample at 90 ° C., the film thickness was further reduced, and the film thickness was 18 μm and the size of the “island” was about 4 μm. For the sample at 120 ° C, the film thickness is further reduced,
When the film thickness was 16 μm, the size of the “island” was reduced to about 1 to 2 μm.

Example 3 A polyamic acid solution was prepared by the following process. 30
In a 0 ml four-neck separable flask, 1.5 g of purified paraphenylenediamine (abbreviation: PPD) and 0.7 g
g of 4,4'-diaminodiphenyl ether (abbreviation:
4,4'-DPE) and 0.5 g of 3,3 ', 4,4'
-Tetraaminobiphenyl / tetrahydrochloride / dihydrate was collected, 50 g of distilled N-dimethylformamide (abbreviation: DMF) was added, and the mixture was stirred and dissolved.

Under a nitrogen atmosphere, the temperature of the external water tank was controlled at 5 ° C., and while stirring the above solution, 4.5 g of purified anhydrous pyromellitic dianhydride (PMDA) was kept solid while maintaining the temperature of the solution. Was carefully added so as not to rise, to prepare a polyimide precursor varnish. 8.00 g of a 6-substituted 3PNC-HEMA (6-substituted 2-hydroxyethyl methacrylate) as a phosphazene monomer was added to 50.00 g of a polyimide precursor varnish containing this solvent, and finally, 2,2 ′ as a photoreaction initiator.
-Bis (o-chlorophenyl) -4,4 ', 5,5'-
1.00 of tetraphenyl-1,2'-biimidazole
g was added.

After that, a pattern of a polymer blend film was formed in the same manner as in Example 1 except that the exposure amount was set to 500 mJ / cm ² (365 nm). This film is scanned with a scanning electron microscope (SE
When observed in M), "sea-island structure" was observed. F
When the “sea” and “island” were analyzed using T-IR, it was found that “sea” was polyimide and “island” was phosphazene. From this, it was found that phosphazene-based polymer fine particles of about 1 to 2 μm were dispersed in the polyimide resin film as the matrix.

Example 4 100 g of the same non-photosensitive polyimide precursor varnish (resin content: 15 wt%) used in Example 1 was used.
Tris (Acroyloxyethyl), a krill polymer
B) After heat-curing the isocyanate, pulverize it with a freeze pulverizer.
Polymer fine particles (particle size: 1-3 μm) obtained by
The coating solution mixed with 15 g and sufficiently stirred was spin-coated on a 3-inch pre-treated Si wafer to form a coating solution of 120 g.
Baking was performed at 30 ° C., 200 ° C., and 280 ° C. for 30 minutes each. The film thickness after post-baking was 10 μm.

This film was used as a stress tester ST-800M
When the stress of the film was measured from the amount of warpage of the Si wafer (manufactured by Canon), it was 27 MPa. On the other hand, the stress of the same non-photosensitive polyimide film (thickness: 10 μm) containing no acrylic polymer fine particles was 35 MPa.

Example 5 The acrylic polymer fine particles (particle diameter:
3 μm) The phosphase used in Example 3 instead of 15 g
3-PNC-HEMA6 substituted product (2-H
(Doxyethyl methacrylate 6-substituted)
20 g of a phosphazene-based polymer (particle size: 2 to 4 μm) pulverized by a freeze-pulverizer or a fluorine-containing polymer (PTF
E, the particle stress was measured in the same manner as in Example 4 except for using 25 g of a particle size of 3 to 5 μm. 25 MPa for 20 g of a phosphazene-based polymer (particle size: 2 to 4 μm) and 23 for 25 g of a fluorine-containing polymer (PTFE, particle size: 3 to 5 μm)
MPa.

Example 6 The film prepared in Example 1 was applied to a stress tester ST-800.
When the stress of the film was measured from the amount of warpage of the Si wafer using M (manufactured by Canon), it was 30 MPa. On the other hand, the stress of the same non-photosensitive polyimide film (thickness: 10 μm) containing no acrylic polymer fine particles was 35 MPa.
Met.

The stress of the film prepared in Example 3 was measured from the amount of warpage of the Si wafer using a stress tester ST-800M (manufactured by Canon).
Met.

Example 7 A process for forming a thin film multilayer circuit using the present invention will be described (FIG. 6). First, 3 inch pre-treated Si
In order to provide insulation on the wafer (425 μm thick) 11, 100 g of the non-photosensitive polyimide precursor varnish (resin content: 15 wt%) in Example 1 was mixed with 15 g of acrylic polymer fine particles (particle diameter: 1 to 3 μm). An insulating film 12 having a thickness of 12 μm was formed by using a sufficiently agitated coating liquid. Next, as the first wiring layer 13, aluminum was sputtered to 3 μm.
A film was attached. Next, a pattern of the resist 14 was formed on the first wiring layer using a positive resist. Pattern 1 formed by exposing this resist 14 to UV light with a mask 15
The first wiring layer 13 'was formed by etching with a ferric chloride solution according to 4'.

On the second insulating layer, a coating liquid obtained by mixing 20 g of acrylic polymer fine particles (particle size: 5 μm) with 100 g of the photosensitive polyimide precursor varnish (resin content: 18 wt%) in Example 3 and sufficiently stirring was used. Using. This photosensitive solution was spin-coated as a second insulating layer 16 and prebaked at 90 ° C. for 1 hour. Next, a glass mask containing a via hole pattern was placed on this dry plate, and the amount of ultraviolet light exposure was 300 mJ / cm.
² (365 nm). Next, ultrasonic immersion development was carried out with an N-methyl-2-pyrrolidone-xylene mixed solution, followed by rinsing with isopropyl alcohol, whereby only the irradiated pattern region remained and the unirradiated region was eluted. After the development, 30 minutes each at 140 ° C. and 350 ° C. in a nitrogen atmosphere.
I baked every minute. Second insulating layer 16 'after post-baking
Was 10 μm.

The above process was repeated three more times for each of the wiring layer and the insulating layer. Finally, an electrode extraction pad was formed, and a multilayer wiring board was manufactured (FIG. 7). FIG.
Among them, 12, 16 ', 18, 20, 22 are insulating layers,
17, 19, 21 and 23 are aluminum wiring layers.
The warpage of the substrate was 80 μm or less, and no disconnection of the wiring layer was observed from the cross section of the multilayer wiring substrate.

On the other hand, a non-photosensitive polyimide precursor varnish containing no acrylic polymer fine particles (resin content: 15 wt%)
Using a photosensitive polyimide precursor varnish (resin content: 18 wt%) containing no acrylic polymer fine particles, a multilayer wiring board was manufactured according to the processes shown in FIGS. The warp of the substrate in the third insulating layer exceeded 100 μm, and the substrate itself was broken when the sputtering apparatus was mounted.

[0058]

According to the present invention, a polymer composite (polymer blend) membrane having a unique sea-island structure and surface can be provided by using the polymer blend according to the present invention. By using a method for producing a polymer blend) film, a method for controlling the size of islands having a unique sea-island structure can be provided.

Further, the insulating film according to the present invention may be used as a protective film for printed circuits, printed boards, wiring boards and electronic parts for high-density mounting.
When used for an interlayer insulating film or the like, it is possible to provide a low-stress insulating film in which, when a multilayer wiring is used, the warpage of the substrate is reduced and the wiring layer is not broken.

[Brief description of the drawings]

FIG. 1 is an electron micrograph showing a particle structure in a sea-island structure of a polymer generated in a process of producing a polymer composite film of the present invention.

FIG. 2 is an electron micrograph showing a particle structure of a surface near a via hole of a polymer composite film of the present invention.

FIG. 3 shows a sea-island structure of a polyimide insulating film of the present invention.

FIG. 4 is an electron micrograph showing a particle structure of a cross section of a polymer composite film of an example.

FIG. 5 is an IR analysis spectrum diagram of the polymer composite of the example.

FIG. 6 shows a step of forming an insulating film according to the embodiment.

FIG. 7 shows a multilayer wiring according to an embodiment.

FIG. 8 shows a conventional process of forming a polyimide insulating film.

[Explanation of symbols]

1,11 substrate 2,12 insulating layer 3,15 mask 13,13 ', 17,19,21,23 aluminum layer 14 resist 16,16', 18,20,22 insulating film

Continuation of front page (72) Inventor Takashi Ito 1015 Uedanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-4-88020 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 79/08 C08L 101/00

Claims (11)

(57) [Claims] 1. A tetracarboxylic acid dianhydride, to aromatic diamines and polyhydric amines polyimide resin obtained as the main component and curing resin na island structure, and the sea surface
Polyimide resin or curable resin is removed and the surface becomes
A polymer composite characterized by being roughened . 2. The polymer composite according to claim 1, wherein the curable resin is an acrylic resin or a phosphazene resin. 3. The polymer composite according to claim 1, wherein the polyimide resin forms a sea and the curable resin forms an island. 4. The polymer composite according to claim 1, which is in the form of a film. 5. A low stress insulating film made of any one polymer composite according to claim 1-4. 6. A method of evaporating a solvent from a composite solution of a polyamic acid containing tetracarboxylic dianhydride, an aromatic diamine and a polyamine as a main component and an uncured resin component while evaporating a solvent, Forming a sea-island structure with the curable resin component, and then or after curing the curable resin component, dehydrating and cyclizing the polyamic acid to form a polyimide resin, thereby forming a sea-island structure between the curable resin and the polyimide resin. A method for producing a polymer composite to be formed.
And evaporate the solvent while maintaining the complex solution at 30-200 ° C.
While making the polyamic acid a sea, an uncured curable tree
After forming a sea-island structure with islands of fat components, uncured islands
After curing the curable resin, the sea is polyamic acid
And producing a polymer composite. 7. A tetracarboxylic dianhydride, an aromatic dia
Polyamic acid mainly containing amine and polyamine
The solvent is evaporated from the composite solution of the curable resin component for curing.
While the polyamic acid and the uncured curable resin component
Form an islands-in-the-sea structure, then cure the curable resin component
Or afterwards, the polyamic acid is dehydrated and ring closed to
A polyimide resin is generated, and a curable resin and a polyimide resin
A method for producing a polymer complex that forms a sea-island structure of fat.
After forming a sea-island structure in which the polyamic acid is the sea and the uncured curable resin component is an island, the uncured curable resin is cured, and then the surface polyamic acid is selectively dissolved to cure the curable resin. To expose the islands and roughen the surface, and then subject the polyamic acid to a dehydration ring-closing reaction to produce a polymer complex.
Construction method. 8. A tetracarboxylic dianhydride, an aromatic dia
Polyamic acid mainly containing amine and polyamine
The solvent is evaporated from the composite solution of the curable resin component for curing.
While the polyamic acid and the uncured curable resin component
Form an islands-in-the-sea structure, then cure the curable resin component
Or afterwards, the polyamic acid is dehydrated and ring closed to
A polyimide resin is generated, and a curable resin and a polyimide resin
A method for producing a polymer complex that forms a sea-island structure of fat.
Te, a polyamic acid as a sea, after the formation of the island to the curable resin component of the uncured and islands, to cure the uncured curable resin which is an island in the selection area, the curable resin of the uncured non-selected areas Production of a polymer composite in which a component and a polyamic acid are selectively dissolved and removed, and then a pattern is formed by performing a dehydration and ring-closing reaction of the polyamic acid in the selected region.
Method. 9. The method according to claim 8 , wherein the composite solution is applied on a substrate to form a pattern of a polymer composite film. 10. A polyamic acid is dispersed in fine particles of an acrylic resin or a phosphazene resin in a polyamic acid solution containing a tetracarboxylic dianhydride, an aromatic diamine and a polyvalent amine as main components, and then the polyamic acid is subjected to a dehydration and ring closure reaction. A polymer composite in which the fine particles are dispersed in a polyimide resin matrix. 11. The method according to claim 10 , wherein the fine particles have a particle size of 5 μm or less.