JP2003029401A - Photosensitive high molecular metallic complex dry film and method for forming metallic circuit using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive high molecular complex for easily forming a metallic film or a metallic circuit on the surface of a substrate with high adhesive strength without using an expensive equipment and to provide a method for forming a metallic circuit using the complex. SOLUTION: A photosensitive high molecular complex solution prepared by dissolving and reacting a palladium compound in a solution of a polyamic acid as a polyimide precursor is applied to a base film (support) and moderately dried to form a photosensitive high molecular complex thin film, the surface of the thin film is covered with a cover film (protective film) to obtain a dry film and this dry film is stuck to a substrate on which a metallic film or a metallic circuit is formed while peeling the cover film. The base film is then peeled to form the photosensitive high molecular complex thin film on the substrate, the thin film is irradiated with UV in the presence of a hydrogen donor to form base nuclei of electroless plating and a metallic circuit is formed by electroless plating or copper electroplating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component material for fine processing and a method for manufacturing a circuit board.

[0002]

2. Description of the Related Art Conventionally, fine processing such as high-density fine wiring and fine vias has been required with downsizing of equipment and increase of signal transmission speed. Therefore, a substrate coated with an aromatic polyamic acid solution has been required. Heat treatment for heat treatment
92, a method for manufacturing a copper-polyimide multilayer substrate described in
Japanese Patent Laid-Open No. 6-77626 proposes a method for forming a plating circuit, which deactivates the catalytic activity of a metal complex by irradiating it with ultraviolet rays.

In the method for producing a copper-polyimide multilayer substrate described in Japanese Patent Laid-Open No. 2-296392, a polyimide resin precursor solution is applied onto a substrate, dried and heated to form a polyimide layer, and the polyimide layer This is a method of directly applying metal plating to the surface. In this method, the plating is limited to the very surface of the polyimide base material, and since the metal circuit part does not have an anchor effect on the polyimide base material, the base material and the metal circuit part The adhesion strength was extremely low.

Further, the method for forming a plating circuit on a ceramic substrate disclosed in Japanese Patent Laid-Open No. 6-77626 has a circuit pattern to be formed by adhering a catalytic treatment liquid containing catalytic metal complex ions on the surface of a base material. A method of irradiating the surface of a substrate with ultraviolet rays by using a resin pattern mask to deactivate the catalytic activity of the portion irradiated with ultraviolet rays, and then immersing the substrate in an electroless plating bath to form a plating circuit in the portion not irradiated with ultraviolet rays. However, in this method, the above-mentioned catalyst treatment liquid is formed by adsorbing the complexing agent solution containing the carboxylic acid group capable of complexing the ions of the catalyst metal on the substrate, and thus forming the metal circuit. There was a problem that the accuracy and the adhesion strength were low.

In order to solve the problems found in the above-mentioned methods, the present inventors have proposed that the polyimide resin precursor is a palladium compound such as an inorganic acid salt of palladium, an organic acid salt or a palladium organic carbonyl complex at room temperature. Reacts with
To form a polymer complex, and further, in the polymer complex, it was found that the palladium ion in the complex is a photosensitive polymer complex which is reduced to palladium metal by ultraviolet irradiation in the presence of a hydrogen donor, Further, as shown in FIG. 3, a photosensitive polyimide precursor resin complex thin film composed of a polyimide resin precursor solution and a palladium compound is formed, and after the thin film is irradiated with ultraviolet rays, electroless plating and electrolytic plating are performed. It has been found that the base material 1 having a metal circuit in which the base material 2 and the metal circuit portion 11 are integrated can be formed.

Then, as a method for forming a metal film or a circuit pattern by a photolithography technique and a plating technique after coating a surface of a substrate with a photosensitive polymer complex solution, Japanese Patent Application Nos. 2001-016339 and 2001-2001.
Japanese Patent Application No. 086874, Japanese Patent Application No. 2001-086875, Japanese Patent Application No. 2001-086876, and Japanese Patent Application No. 2001
The methods described in Japanese Patent Application No. 086877 and Japanese Patent Application No. 2001-179646 were devised.

[0007]

However, in the above method, as shown in FIG. 4, since the viscosity of the photosensitive polymer complex solution increases with the passage of time, in order to obtain a thin film having a constant film thickness, Liquid preparation and viscosity control in the coating process,
There is a problem that it is necessary to perform wet coating.

According to the present invention, the photosensitive polyimide precursor resin complex solution is applied to a base film, dried, covered with a cover film, processed into a dry film, and used to form a metal circuit. Processes such as liquid preparation, viscosity control, and wet coating are unnecessary when forming a metal circuit, and
It is intended to provide a method for forming a metal circuit having excellent adhesiveness at low cost on various base materials.

[0009]

In order to solve the above problems, in the present invention, as described in claim 1, the photosensitive polymer complex dry film comprises at least a base film and a photosensitive polymer complex thin film. And a cover film.

Further, as described in claim 2, a metal circuit is formed on the substrate by using a photosensitive polymer complex dry film including at least a base film, a photosensitive polymer complex and a cover film. It is what

The base material on which the metal circuit is formed may be at least one of resin, ceramic, silicon and metal.

As described above, according to the present invention, when a metal circuit is formed on a substrate through a polyimide insulating film, a photosensitive polymer obtained by dissolving and reacting a palladium compound in a polyamic acid solution which is a polyimide resin precursor. By using the complex dry film and the photolithography technique, the metal circuit can be easily formed at a low cost. Moreover, by imidizing the polyimide resin precursor, heat resistance and chemical resistance are also improved, and the interline insulation after wiring formation is also excellent, and it can be sufficiently used as an electronic component material for fine processing. is there.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows one embodiment of the photosensitive polymer complex dry film in the present invention.

For the photosensitive polymer complex dry film 3, a photosensitive polymer complex solution prepared by dissolving and reacting a palladium compound in a polyimide resin precursor solution is applied to a base film (support) 3b by a bar coater, a roll coater or the like. After that, it is dried to form a photosensitive polymer complex thin film 3a having adhesiveness on the surface, and then a cover film (protective film) 3c is attached on the photosensitive polymer complex thin film to form a dry film. is there.

The base film 3b is made of polyester, and the cover film is made of polyethylene. Base film 3b and photosensitive polymer complex thin film 3
The adhesive force of a is stronger than the adhesive force of the cover film 3c and the photosensitive polymer complex thin film 3a.

When the photosensitive polymer complex thin film 3a is formed, leveling at room temperature and heat drying are used together. In heat drying, the temperature is below the thermal decomposition temperature of the metal complex, usually 150.
Dry at a temperature below ℃.

Further, since the viscosity of the photosensitive polymer complex solution changes as the reaction progresses as described later, it is important to apply the solution quickly after the preparation. After preparing the liquid, 1
The base film 3b is preferably applied within the time, and particularly preferably within 15 minutes.

The film thickness of the photosensitive polymer complex thin film 3a after drying is usually 0.1 to 10 μm, and the palladium complex concentration in the photosensitive polymer complex thin film 3a is 0.1 to 10 weight.
It is about%.

In the case of forming a film in the form of a dry film, the photosensitive polymer complex solution is applied relatively thinly on the base film 3b, and then the polyimide resin precursor solution containing no palladium compound is overlaid and applied thickly. It is possible to form a dry film having a film thickness. The method described above is also preferable in terms of saving expensive palladium and ensuring the thickness of the polyimide insulating film. It is also possible to apply a photosensitive polymer complex solution and a polyimide resin precursor solution containing no palladium compound to both surfaces of a commercially available polyimide base material and process only the surface into a sticky dry film. .

FIG. 1 shows one embodiment of a metal circuit forming method according to the present invention.

The cover film 3c of the photosensitive polymer complex dry film 3 is peeled off or after being peeled off, and then pressure-bonded on the base material 2 (FIG. 1 (a)), and the base film 3b is peeled off. Photosensitive polymer complex thin film 3a on the material 2
Is formed (FIG. 1 (b)), the photosensitive resin 4 is applied on the photosensitive polymer complex thin film 3a (FIG. 1 (c)), and the photosensitive resin 4 is formed.
Is exposed and developed to form a resin pattern mask 5 in which the photosensitive polymer complex thin film 3a of the metal circuit portion 6 is exposed (FIG. 1D).

Then, ultraviolet rays 9 are irradiated through the resin pattern mask 5 in the presence of a hydrogen donor 8 such as water, alcohol or an aqueous alcohol solution (see FIG. 1).
(E)), a plating base nucleus is formed by reducing palladium ions in a palladium compound in the photosensitive polymer complex thin film 3a to palladium metal, and a plating base metal layer 10 is formed by an electroless plating process (Fig. 1 (f)).

Further, the substrate 1 is electroplated to form the metal circuit portion 11 having a predetermined film thickness on the plating base metal layer 10 (FIG. 1 (g)).

Then, the resin pattern mask 5 is peeled off (FIG. 1 (h)), and the photosensitive polymer complex thin film 3a of the non-metal circuit portion 7 is removed (FIG. 1 (i)), in vacuum or By heating at 400 ° C. in a nitrogen atmosphere to imidize the polyimide resin precursor, a substrate 1 having a metal circuit is obtained (FIG. 1 (j)). Imidization may be performed at any stage before and after electrolytic plating as long as it is after the formation of the plating base metal layer by electroless plating.

The photosensitive polymer complex thin film 3 is formed on the substrate 2.
The process after forming a is not limited to the above process, and the hydrogen donor 8 is formed through the photomask in which the metal circuit portion 6 is opened and the nonmetal circuit portion 7 is shielded from light.
Ultraviolet light 9 in the presence of
After irradiating the substrate, the photomask is removed, and after irradiating with ultraviolet light 9 in the air (in the absence of a hydrogen donor), the metal circuit portion 6 is subjected to electroless plating, electrolytic plating, and imidization. Other methods such as forming the material 1 that the inventors have applied for so far may be used.

The base material 2 used in the present invention includes an insulating base material made of at least one of resin, ceramics, silicon and metal, various electronic circuit boards and silicon wafer boards, for example, polyimide resin and stainless steel. , Copper, etc.

In consideration of imidization, a polyimide resin or liquid crystal polymer having a heat distortion temperature of 280 ° C. or higher is preferable. As the polyimide resin, pyromellitic anhydride (PMDA) and oxydianiline (OD
Polyimide consisting of A), biphenyl tetracarboxylic acid anhydride (BTDA) and p-phenylenediamine (PD
A) polyimides and copolymers of these monomers, aromatic tetracarboxylic acid anhydrides and -O in the molecule.
-, -CO-, -Si-, a thermoplastic polyimide comprising an aromatic diamine having a bending group, and a solvent-soluble thermoplastic polyimide such as a copolymer with an alicyclic carboxylic acid anhydride These polyimide resins are mainly used as film substrates in the field of electronic component materials.

When a polyimide resin is used as the substrate 2, by imidizing, the substrate and the photosensitive polymer thin film layer become homogeneous and the adhesion strength between the metal circuit and the substrate becomes very strong.

As the polyamic acid as the polyimide resin precursor solution, commercially available pyromellitic dianhydride (PMD) is used.
Polyamic acid consisting of A) and oxydianiline (ODA), biphenyl tetracarboxylic acid anhydride (BTDA)
And a polyamic acid varnish obtained from a copolymer of p-phenylenediamine (PDA), a copolymer of these monomers, and an alicyclic carboxylic acid anhydride, and a photosensitive group in the molecule. A polyamic acid varnish containing the like is applicable. Typical examples of polyamic acid varnishes include Toray's polyimide resin precursor varnishes "Trenice" and "Photonice".
Examples include “semicofine” and polyimide resin precursor varnish “U-varnish” manufactured by Ube Industries. Further, the polyimide resin precursor varnish and the solvent-soluble polyimide varnish can be mixed and used. Examples of solvent-soluble polyimide varnishes include thermoplastic polyimide varnish “SPI-200N” manufactured by Nippon Steel Chemical.

As the palladium compound which serves as a catalyst for electroless plating in the present invention and which forms a complex with the polyimide precursor resin, there are various salts of palladium and organic carbonyl complexes. Examples of the palladium salt include hydrochloride, sulfate and acetic acid. Salts, oxalates, citrates and the like can be mentioned. Examples of organic carbonyl compounds include β-diketones such as acetylacetone and dibenzoylmethane, and β-ketocarboxylic acid esters such as ethyl acetoacetate.

In particular, organic salts and complex compounds such as palladium acetate and acetylacetone complex are easily available, and solubility in organic solvents, thermal stability, and residual inorganic ions such as chlorine ions in the resin after photoreaction. It is used because it does not remain. These complexes are dissolved in n-methyl-2-pyrrolidinone (NMP) or NN'-dimethylacetamide (DMAc), which are solvents for the polyimide resin precursor, and then uniformly mixed and dissolved in the polyimide resin precursor varnish.

The formation of the polymer complex in the reaction between the polyimide resin precursor and the palladium compound is clear from the increase in the viscosity of the polyimide resin precursor varnish and the gel formation when the complex is added to the varnish as shown in FIG. is there. When the copper (II) acetylacetone complex is added to the polyimide resin precursor solution instead of the palladium acetylacetone complex, the viscosity change of the solution and the gelation phenomenon do not occur at all.

Therefore, it is considered that the metal complex formation of the polyimide resin precursor is peculiar to palladium ion. In this case, it is considered that the palladium ion probably reacts with the functional group of the polyimide resin precursor to form a complex in which a metal ion is coordinated in the polymer molecule and is incorporated as one component. That is, in the photosensitive polymer complex thin film formed by applying and drying this solution on the base film, not only the metal ions are uniformly distributed in the thin film layer, but also one of the polymer molecules on the surface of the thin film is It is considered that the components are distributed so as to be exposed on the surface.

As the ultraviolet rays 9 used in the present invention, ultraviolet rays having a wavelength of 450 nm or less emitted from a mercury ultraviolet lamp or an ultraviolet laser generator are effective.
Ultraviolet rays around m are particularly effective. A commercially available low-pressure mercury lamp can be used as the ultraviolet lamp, but a laser generator or the like may be used. It is considered that when irradiated with ultraviolet rays, the palladium compound absorbs light and is excited, and the palladium ion in the exciplex molecule is reduced to a metal in the presence of a hydrogen donor. This is also clear from the results of XPS measurement of the surface of the photosensitive polymer complex thin film irradiated with ultraviolet rays in the presence of a hydrogen donor shown in FIG. 5, from the fact that palladium ions are reduced to metallic palladium.

The UV irradiation amount is 500 to 150 when measured with an UV illuminance meter UV-02 manufactured by Oak Manufacturing Co., Ltd.
Requires mJ / cm ² energy of about, in particular, about 1500~9000mJ / cm ² is preferred.
If the irradiation amount of ultraviolet rays is 500 mJ / cm ² or less, the palladium ions of the palladium compound may not be completely reduced to palladium metal, and if it is 15000 mJ / cm ² or more, the polyimide resin precursor layer may be damaged. When the ultraviolet irradiation dose is 1500 to 9000 mJ / cm ² , palladium ions are stably reduced to palladium metal.

The irradiation time required to obtain the above-mentioned ultraviolet irradiation amount varies depending on the irradiation intensity of ultraviolet rays, but the irradiation time of a normal ultraviolet lamp is about 1 to 20 minutes, and in the case of ultraviolet irradiation from a laser generator. The irradiation time is within 60 seconds.

In order to accelerate the photoreaction of the complex compound, a sensitizer may be added as long as the adhesion between the metal and the polyimide is not adversely affected.

Examples of the hydrogen donor 8 include water, alcohol, and alcohol aqueous solution. In particular, the hydrogen donor 8 has little ultraviolet absorption in the above-mentioned ultraviolet wavelength range, and has appropriate wettability with the surface of the photosensitive polymer complex thin film 3a. An alcoholic aqueous solution is preferably used. It should be noted that the reaction of reducing the metal ion to the metal is inhibited by the presence of oxygen, so it is preferable to block oxygen (air) during irradiation. Usually, the irradiation is often performed while the substrate 1 is immersed in the hydrogen donor 8, but when the hydrogen donor 8 is water, irradiation is performed while supplying water from the outside by irradiation in water or the like. It is also possible to preliminarily adsorb moisture sufficiently to the photosensitive polymer complex thin film 3a before use.

The electroless plating bath for forming the plating base metal layer 10 is not particularly limited, but is usually neutral considering the barrier properties against metal ions and the chemical resistance (alkali resistance) of the polyimide resin precursor. Therefore, a weakly acidic hypophosphite-based or dimethylaminoborane-based nickel plating bath is preferably used. Further, as the electrolytic plating bath, a usual electrolytic copper plating or electrolytic nickel plating bath can be used.

The photosensitive polymer complex dry film 3 of the present invention is laminated on the substrate 2 to form a photosensitive polymer complex thin film 3a.
FIG. 7 is a top view (SEM photograph) of a case where a comb-shaped plating resist pattern is formed on the surface of the photosensitive resin 4 for plating resist after the formation of the same and electroless nickel plating is performed.
Shown in. It can be seen that a wiring pattern of L / S = 50/50 μm is formed. The insulation resistance between the wires obtained by this method was measured by JISC-5016, and as a result, 1.5 × 1
A high insulation resistance of 0 ¹² Ω · cm was obtained.

[0041]

Example 1 A photosensitive polymer complex solution prepared by dissolving a palladium acetylacetone complex (hereinafter abbreviated as a palladium complex) in n-methyl 2-pyrrolidinone (hereinafter abbreviated as NMP) was used as a polyimide precursor varnish manufactured by Toray. It is added to "Trenice"# 3000 and adjusted so that the content of the palladium complex in the varnish solution is 1 wt / vol%. The solution is approximately 5 wt% per polyimide resin precursor
The palladium complex of is contained.

Next, the solution was applied to a 25 μm-thick Toray polyester film “Lumirror” with a roll coater, dried at room temperature, and then dried at 120 ° C. for 30 minutes. After repeating this step 3 times, the surface was covered with a polyester film having a thickness of 25 μm to form a photosensitive polymer complex dry film. The film thickness of the photosensitive polymer complex thin film was 6 μm.

One piece of 10 × 10 cm (thickness: 50 μm) of a polyimide base material “UPILEX-S” manufactured by Ube Industries, Ltd.
% NaOH aqueous solution and 1% HCL aqueous solution to roughen the surface, wash with pure water and dry, then peel the base film of the photosensitive polymer complex dry film to obtain the photosensitive polymer complex dry film. The substrate was overlaid, pressed with a vacuum press, preliminarily dried at 60 ° C., the cover film was removed, and further dried at 120 ° C. for 1 hour.

A 20% ethanol aqueous solution was dropped on the substrate, sandwiched between quartz plates, and ultraviolet rays from a low pressure mercury lamp were irradiated for 3 minutes while the air was blocked by the aqueous solution film. The irradiation amount of ultraviolet rays was 4500 mJ / cm ² as a result of measurement with an illuminance meter UV-02 manufactured by Oak Manufacturing Co., Ltd.

The base material was placed in an electroless nickel bath "Enplate Ni-426" (PH = 6 to 7), which was heated to 65 ° C. and used as a reducing agent of sodium hypophosphite manufactured by Meltec.
When soaked for a minute, a plating with a uniform metallic luster was formed only on the UV-irradiated part. With respect to the nickel-plated substrate, the Auger spectra in the depth direction of the nickel-plated portion and the photosensitive polymer complex thin film portion are measured. The results are shown in FIG. It was detected even inside the thin film portion, and it was confirmed that nickel metal was present in the polymer layer.

Furthermore, in the electrolytic copper plating bath, 3.3 A / dm
Electroplating was performed at a current density of ² to obtain a copper clad substrate having a copper film thickness of 24 μm.

The copper clad substrate thus obtained was dried at 150 ° C. in a nitrogen atmosphere and then heated to 400 ° C.,
After holding at 400 ° C. for 15 minutes to perform imidization, it was cooled to room temperature (20 ° C. to 25 ° C.) in a nitrogen atmosphere to obtain a copper-clad base material having metallic luster.

The adhesion (adhesion) strength between the metal of the copper clad substrate thus obtained and the polyimide was measured by the method specified in JIS C-6481 and found to be 1000 gf / cm (1
A peel strength of 0 N / cm) was obtained.

Next, a dry film type photoresist was used for the copper clad substrate obtained by the above method, exposed and developed, and then L / S = 100/1 with a ferric chloride type etchant.
00 (μm) wiring pattern was prepared, the nickel plating layer in the space was etched with an acidic hydrogen peroxide solution, and a photosensitive polymer complex thin film was formed with an aqueous solution of potassium permanganate having a concentration of 0.1 mol / L. Removed. The insulation resistance between the wirings of the obtained base material having a metal circuit is measured according to JISC-501.
As a result of the measurement in No. 6, 1.5 × 10 at an applied voltage of 100V
It was ¹² Ω · cm.

Example 2 A commercially available palladium complex was used as NM.
The photosensitive polymer complex solution dissolved in P was added to Toray's polyimide resin precursor varnish “Semicofine”, and the content of the palladium complex was 1 wt / vol% per varnish solution.
I adjusted it to be. The solution contains approximately 5 wt% palladium complex per polyimide resin precursor.

Next, the solution was applied to a 25 μm-thick Toray polyester substrate “Lumirror” by a roll coater, dried at room temperature, and then dried at 120 ° C. for 30 minutes.
After repeating this step three times, the surface was covered with a polyester film having a thickness of 25 μm and processed into a photosensitive polymer complex dry film. The film thickness of the photosensitive polymer complex thin film was 5 μm.

1% of a 10 × 10 cm (50 μm thick) test piece of polyimide base material “Kapton EN” manufactured by Toray DuPont
After roughening the surface with a NaOH aqueous solution and a 1% HCL aqueous solution, washing with pure water and drying, the base film of the photosensitive polymer complex dry film is peeled off,
The photosensitive polymer complex dry film was overlaid on a substrate, pressed against it by a vacuum press, preliminarily dried at 60 ° C., the cover film was removed, and further dried at 120 ° C. for 1 hour.

The polyimide of the polyimide base material
Acrylic photosensitive resin made by Nigo Morton Co., Ltd. on the resin precursor layer
Resin dry film "NIT225" (thickness 25 μm)
Laminated at 130 ° C, L / S = 200/200
(Μm) wiring pattern through a polyester mask
The diffused UV light from the high pressure mercury lamp is 85mJ / c.
m ^TwoExposure treatment was performed. Dedicated development of photosensitive resin
Liquid (1% Na_TwoCO₃Aqueous solution) at room temperature for 30 seconds
After washing with water, the photosensitive polymer complex thin film on the metal circuit is exposed
A base material having the resin pattern mask was obtained.

A 20% ethanol aqueous solution was dropped on the substrate, sandwiched between quartz plates to form an ethanol aqueous solution film, and irradiated with ultraviolet rays from a low-pressure mercury lamp for 5 minutes. The irradiation amount of ultraviolet rays was 7500 mJ / cm ² as a result of measurement with an illuminance meter UV-02 manufactured by Oak Manufacturing Co., Ltd.

Next, the electroless nickel bath "Emplat Ni-426" (PH = 6 to 7) using Meltec sodium hypophosphite as a reducing agent, in which the base material is heated to 65 ° C.
When it was immersed for 5 minutes, a plating having a uniform metallic luster was formed only on the metal circuit portion, and a metal circuit was formed.

3.3 A / d of electrolytic copper plating bath on the substrate
Electroplating was performed at a current density of m ² to obtain a substrate having a polyimide resin precursor layer having a metal circuit pattern with a copper film thickness of 5 μm.

Then, after performing etching treatment at 70 ° C. for 2 minutes with an etching solution “TPE3000” manufactured by Toray Engineering Co., Ltd., it was washed with water to remove the photosensitive polymer complex thin film in the non-metal circuit part, and then the above-mentioned base material was removed. After drying at 150 ° C. in a nitrogen atmosphere and further heating to 400 ° C. and holding in the state of 400 ° C. for 15 minutes to imidize the polyimide resin precursor layer, the polyimide resin precursor layer was imidized, and then at room temperature (20 ° C.) in a nitrogen atmosphere. To 25 ° C), L / S = 150/15
A base material having a metal circuit of 0 (μm) was obtained.

The insulation resistance between lines of the metal circuit of the base material for electronic parts was measured by JISC-5016, and was 1.0 ×
The insulation resistance value was as high as 10 ¹² Ω · cm.

Example 3 A sample of polyimide base material “Kapton EN” manufactured by Toray DuPont 10 × 10 cm (thickness: 50)
surface is roughened with 1% NaOH aqueous solution and 1% HCL aqueous solution, washed with pure water and dried,
The base film of the photosensitive polymer complex dry film formed by the same method as in Example 1 was peeled off, the photosensitive polymer complex dry film was overlaid on the substrate, pressed with a vacuum press, and preliminarily dried at 60 ° C. The cover film was removed, and the film was further dried at 120 ° C. for 1 hour.

Then, an alkali-developing dry film "NIT2" made by Nigo Morton was formed on the surface of the photosensitive polymer metal thin film.
25 ″ was laminated and exposed and developed through a mask having a comb-shaped electrode circuit pattern of L / S = 50/50 (μm) to form a plating resist pattern.

A water film is formed by wetting the surface of the substrate having the pattern resist, and L / S = 150 from above the water film.
/ 150 (μm) with a wiring pattern of a metal circuit portion having an opening photomask is adhered to the substrate with a water film sandwiched,
Ultraviolet rays from a low-pressure mercury lamp were applied to the metal circuit portion for 3 minutes through a photomask. The irradiation amount of ultraviolet rays was 7500 mJ / c as a result of measurement with an illuminance meter UV-02 manufactured by Oak Manufacturing Co., Ltd.
It was m ² .

Next, the electroless nickel bath "Enplate Ni-426" (PH = 6 to 7) using sodium hypophosphite manufactured by Meltec, which has been heated to 65 ° C. as the reducing agent, is used as the base material.
When immersed for 5 minutes, plating with uniform metallic luster was generated only on the metal circuit portion, and the same metal circuit as the opening pattern of the photomask was formed.

3.3 A / d of electrolytic copper plating bath on the substrate
Electroplating was performed at a current density of m ² to obtain a base material having a comb-shaped electrode circuit with a copper film thickness of 10 μm and a copper film thickness of 10 μm.

After removing the plating resist and heating and imidizing at 370 ° C., the photosensitive polymer complex thin film remaining in the wiring space portion is etched at 80 ° C. for 2 minutes with Toray Engineering etching solution “TPE-3000”. It was removed. As a result of measuring the insulation resistance between the wirings of the obtained base material by JISC-5016, an applied voltage of 100
It was 1.5 × 10 ¹² Ω · cm in V.

(Example 4) The base film of the photosensitive polymer complex dry film formed by the same method as in Example 2 was peeled off and overlapped with an 8-inch silicon wafer and pressed.
After drying at room temperature, it is dried at 120 ° C for 30 minutes, and a semi-cofine coated surface is laminated with Nigo Morton's alkaline development type dry film "NIT225".
A plating resist pattern was formed by exposing and developing through a mask having a comb-shaped electrode circuit pattern of S = 50/50.

The surface of the substrate having the plating resist pattern was wetted to form a water film, which was sandwiched between quartz plates, and ultraviolet rays from a low-pressure mercury lamp were irradiated for 5 minutes while the air was blocked by the water film. The irradiation amount of ultraviolet rays was measured by an illuminance meter UV-02 manufactured by Oak Manufacturing Co., Ltd. and found to be 7500 mJ / cm ²
Met.

This irradiated film was heated to 65 ° C., and an electroless nickel bath "Enplate Ni-426" (PH = 6 to 6) using sodium hypophosphite manufactured by Meltec as a reducing agent was used.
When it was dipped in 7) for 5 minutes, nickel plating with a uniform metallic luster was attached only to the part where the semicofine was exposed from the dry film, and nickel wiring was obtained. Furthermore, when electroplating was performed in an electrolytic copper plating bath at a current density of 3.3 A / dm ² , a comb-shaped electrode circuit with a copper / Ni wiring having a copper film thickness of 10 μm was obtained. The insulation resistance between the wirings of the obtained film was measured by JISC-5016, and as a result, it was 1.4 × 10 ¹² Ω · cm at an applied voltage of 100V.
Met.

(Example 5) The base film of the photosensitive polymer complex dry film formed in the same manner as in Example 2 was peeled off to form a photosensitive polymer complex dry film and 10c.
mx 10 cm ceramic substrates are stacked and pressed together at 60 ° C.
The sample was heated and pre-dried at, the cover film was removed, and further dried at 120 ° C. for 1 hour.

Then, an alkali-developing dry film "NIT2" made by Nigo Morton was formed on the surface of the photosensitive polymer metal thin film.
25 "was laminated, and a plating resist pattern was formed by exposing and developing through a mask having a comb-shaped electrode circuit pattern of L / S = 50/50 (μm).

The surface of the base material having the plating resist pattern was wetted to form a water film, which was sandwiched between quartz plates, and while the air was blocked by the water film, ultraviolet rays from a low-pressure mercury lamp were used for 5 hours.
Irradiated for minutes. The irradiation amount of ultraviolet rays was 7500 mJ / cm ² as a result of measurement with an illuminance meter UV-02 manufactured by Oak Manufacturing Co., Ltd.

Next, the electroless nickel bath "Enplate Ni-426" (PH = 6 to 7) using Meltec's sodium hypophosphite as a reducing agent, in which the above base material is heated to 65 ° C.
When it was immersed for 5 minutes, a plating having a uniform metallic luster was formed only on the metal circuit portion, and a metal circuit was formed.

Furthermore, in the electrolytic copper plating bath, 3.3 A / dm
^When electroplating was performed at a current density of ^2, a copper film thickness of 10
A comb-type electrode circuit having a copper / Ni wiring of μm was obtained. The insulation resistance between the wirings of the obtained base material was measured by JISC-5016, and as a result, it was 1.5 × 10 ¹² Ω · c at an applied voltage of 100V.
It was m.

[0073]

As described above, in the present invention, attention is paid to the fact that the polyimide precursor polyamic acid and palladium ions form a photosensitive polymer complex, and this photosensitive polymer complex is coated on the base film.・ After drying and processing into a dry film, by laminating it on various substrates, a photosensitive polymer complex film is formed on the substrate surface, and further a metal film is formed by UV exposure and electroless plating. This is a method, and a wiring circuit and the like can be easily formed in a small number of steps by photolithography using a plating resist and mask exposure. Apply a liquid photosensitive polymer complex solution to the surface of a conventional substrate and dry it,
Compared with the method of forming a photosensitive polymer complex film, there is no need for on-site liquid preparation or liquid viscosity control, and stable work is possible in a relatively short time. As described above, the manufacturing process of a metal circuit substrate using a dry film made of a photosensitive polymer complex obtained by dissolving and reacting a palladium compound in a polyamic acid solution is extremely excellent for fine wiring processing and has high utility value. It is a thing.

The photosensitive polymer dry film of the present invention comprises
As described in claim 1, since it is composed of at least a base film, a photosensitive polymer complex thin film and a cover film, it is possible to prepare a solution or a viscosity when forming a photosensitive polymer complex film when forming a metal circuit. Processes such as management and wet coating are unnecessary.

In the metal circuit forming method for forming a metal circuit on a substrate by using a dry film as described in claim 2, since the dry film is a photosensitive polymer complex dry film, adhesion is achieved at low cost. A metal circuit having excellent strength can be formed on various substrates.

The base material forming the metal circuit is resin,
Since it is made of at least one of ceramic, silicon, and metal, it is possible to form a metal circuit having excellent adhesion with the substrate on various types of base materials.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a method for forming a metal circuit pattern according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a constitution of a photosensitive polymer complex dry film in the present invention.

FIG. 3 is a cross-sectional view of a substrate formed by the metal circuit forming method of the present invention.

FIG. 4 is a diagram showing a change in viscosity when a palladium acetylacetone complex is added to a polyimide resin precursor solution and a change in viscosity of the polyimide resin precursor solution.

FIG. 5 is a diagram showing XPS analysis results showing changes in the binding energy of palladium in a palladium complex-containing resin thin film layer before and after irradiation with ultraviolet rays.

FIG. 6 is an Auger analysis chart of a nickel-plated portion and a photosensitive polymer complex thin film after electroless nickel plating.

FIG. 7 is a top view of a metal circuit formed by the metal circuit forming method of the present invention.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Fumimi Ozaki             Toray, 1-41 Oe, Otsu City, Shiga Prefecture             Engineering Co., Ltd. (72) Inventor Atsushi Suzuki             1 103-54, Yoshinodai, Kawagoe City, Saitama Prefecture             Inside Tech Co., Ltd. (72) Inventor Yuko Hashino             1 103-54, Yoshinodai, Kawagoe City, Saitama Prefecture             Inside Tech Co., Ltd. F-term (reference) 2H025 AB11 AB15 AB16 AC01 BH04                       DA01                 4F071 AA60 AC09 AE22 BB02 BC01                 5E343 AA02 AA18 AA22 AA23 AA38                       BB16 BB21 BB71 CC71 CC73                       DD33 DD43 DD76 ER18 GG01

Claims (3)

[Claims] 1. A photosensitive polymer complex dry film comprising at least a base film, a photosensitive polymer complex thin film and a cover film. 2. A metal circuit forming method for forming a metal circuit on a substrate using a photosensitive polymer complex dry film comprising at least a base film, a photosensitive polymer complex thin film and a cover film. 3. The base material is resin, ceramic, silicon,
The metal circuit forming method according to claim 2, wherein the metal circuit is formed of at least one of metals.