JPH06302937A - Formation of conductor circuit for printed wiring board - Google Patents

Abstract

PURPOSE:To provide a method wherein plating resist is completely eliminated without cutting and damaging wiring, and a fine circuit can be formed, when the conductor circuit of a printed wiring board is formed. CONSTITUTION:On substratum metal 2 formed on an insulative board 1, a plating resist pattern 3 whose main component is acryl based compound is formed so as to correspond to a wiring pattern, and a conductor circuit 4 as the wiring pattern is formed by plating. The plating resist pattern 3 is exfoliated by using a peeling liquid, and treated by using a resist elimination pretreatment liquid which cuts at least a part of chemical bonds in the plating resist, or resist elemination pretreatment liquid composed of a solution of strong acid or alkali metal hydroxide. After rinsing, the substratum metal 2 is etched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a conductor circuit of a printed wiring board, which is suitable for forming high density and fine circuits on the printed wiring board.

[0002]

2. Description of the Related Art Conventionally, as a method for forming a conductor circuit of a printed wiring board, a copper clad laminate is used as a starting material,
A method of providing an etching resist on the circuit portion and removing the portion other than the circuit by etching has been generally performed. However, in the etching method, not only in the thickness direction of the circuit,
Since the etching also progresses in the width direction, the cross-sectional shape of the circuit is not a rectangle but a trapezoid with a wide width on the substrate side. Therefore, when the wiring becomes dense and the width of the wiring approaches the thickness of the circuit, it is difficult to obtain a sufficient circuit cross-sectional area. Further, since the dimensional accuracy of the circuit is determined by the variation in the etching amount, there is a problem that it is difficult to form fine wiring with high accuracy. Therefore, in order to form such a high-density wiring, the pattern plating method has been used instead of the usual etching method.

In the pattern plating method, a copper clad laminate is used as a starting material, a plating resist (a resist provided for forming a plating pattern) is provided on a portion of a copper foil where a circuit is not formed, and the plating resist is covered. A conductor circuit is formed by plating a portion that is not exposed, that is, a circuit formation portion. After that, the plating resist is removed, and further, the underlying copper other than the circuit is removed by etching to form an independent circuit. in this way,
Since the conductor circuit is formed according to the shape of the plating resist,
The circuit width formation accuracy is determined by the plating resist formation accuracy. Therefore, by using a photosensitive plating resist and forming a resist pattern by a photographic method, fine wiring can be formed with high accuracy.

In such a pattern plating method, it is essential that the plating resist is sufficiently adhered to the substrate to prevent peeling and blistering in the plating step, and to completely peel and remove the plating resist after the plating is completed. That is, contradictory properties such as high adhesion of the resist up to the plating step and good peelability in the resist removal step are required. In particular, when the conductor circuit is formed by chemical copper plating, peeling or swelling of the resist is likely to occur during the plating process, and therefore it is necessary to improve the adhesion of the plating resist. As a method for improving the adhesion of a plating resist and preventing peeling or blistering in the plating process, there is disclosed in Japanese Patent Laid-Open No.
4-13794, JP-A-1-261888 and the like.

For removing the resist by stripping, a chlorine-based organic solvent such as dichloromethane, an alkaline resist stripping solution or the like is usually used according to the properties of the resist. However, when the adhesiveness of the resist is high, the resist cannot be completely removed by the above-described peeling process, and there is a case where the resist residue adheres partially to the underlying copper foil other than the circuit. was there. If such a resist residue is present, copper in this portion cannot be removed in a subsequent etching step, which causes defects such as a short circuit and a short circuit gap.

[0006] Therefore, as a method for removing the residue attached to the resist, in JP-A-60-206190, the photoresist remaining after the resist stripping treatment is immersed in a strong acid and then brushed with an acid resistant brush to remove it. The method is shown.

[0007]

When mechanical means such as brushing is used to remove the resist residue as in the above-mentioned prior art, there is a problem that it is easy to damage, peel or cut fine wiring. It was Further, there is a problem that some of the chlorine-based organic solvents used as the stripping solution are not preferable from the viewpoint of environmental protection.

A first object of the present invention is, when removing a plating resist, completely removing the resist without cutting or damaging the wiring and forming a fine circuit conductor of a printed wiring board. It is to provide a circuit forming method.

A second object of the present invention is to provide a method for forming a conductor circuit on a printed wiring board, which can remove the plating resist without performing a stripping treatment with a chlorine-based organic solvent.

[0010]

In order to achieve the first object, the method for forming a conductor circuit of a printed wiring board according to the present invention is such that an acrylic compound is mainly formed on a base metal provided on an insulating board. A resist removal pretreatment liquid or a strong acid that provides a plating resist as a component according to the wiring pattern, forms the wiring pattern by plating, peels the plating resist with a peeling solution, and cuts at least a part of the chemical bonds in the plating resist. Alternatively, the plating resist is treated with a resist removal pretreatment liquid consisting of a solution of an alkali metal hydroxide, the plating resist is washed with water, and the underlying metal is etched.

In order to achieve the above second object,
The method for forming a conductor circuit of a printed wiring board according to the present invention is to provide a plating resist containing an acrylic compound as a main component on a base metal provided on an insulating plate according to a wiring pattern,
Consists of a resist removal pretreatment liquid or a strong acid or alkali metal hydroxide solution that forms a wiring pattern by plating and cuts at least a part of the chemical bonds in the plating resist without treating the plating resist with a peeling liquid. The plating resist is treated with a resist removal pretreatment liquid, the plating resist is washed with water, and the underlying metal is etched.

The plating resist composition used in the present invention includes a compound having a chemical bond which is easily cleaved by a decomposition reaction by a resist removal pretreatment liquid, a compound which is easily imparted hydrophilicity as a resist by the resist removal pretreatment liquid, or both of them. It is preferable to use a compound containing a compound having an action as a main component. As a result of studying various resins as such a compound, it was found that an acrylic compound is excellent in characteristics and most suitable.

Examples of the acrylic compound include methacrylic acid compounds such as methacrylic acid and methacrylic acid esters, and acrylic acid compounds such as acrylic acid and acrylic acid esters. Such compounds include methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Butyl methacrylate, hexyl methacrylate, lauryl methacrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, trimethylolpropane trimethacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxypropyl acrylate, butanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, neopentyl glycol diacrylate, trimethylolpropane triacrylate , Pentaerythritol triacrylate, pentaerythritol tetraacrylate There is a dipentaerythritol hexa-acrylate, and the like.

These compounds are polymers, if necessary.
Used as an oligomer and a monomer. For example, polymethylmethacrylate used as a polymer component of a dry film, polyfunctional acrylate used as a crosslinking component of a resist (a plurality of acryloyl groups (CH ₂ ═CH
Acrylic acid ester) monomer having CO-).

When the plating for forming the wiring pattern is the chemical copper plating, the resist is likely to be peeled off particularly in the plating process, and therefore a treatment for strengthening the adhesion between the resist and the base is used. The effect of the invention is great.

As the form of the plating resist, there are a screen printing resist, a photosensitive resist and the like, but it is advantageous to use the photosensitive resist and a photographic method process in forming a high precision pattern. For example, a dry film photoresist may be laminated with a hot roll, a pattern image may be exposed through a photomask and then developed to form a resist pattern. As the photoresist, in addition to the dry film type, a liquid photoresist may be applied by a method such as screen coating, roll coating or curtain coating.

In order to remove the resist residue more effectively, ultrasonic waves may be applied to the resist removal pretreatment liquid, or the resist removal pretreatment liquid may be sprayed onto the substrate. Similarly, ultrasonic treatment or spray water washing can be performed in the water washing step after the treatment with the resist removal pretreatment liquid. In addition, ultrasonic treatment can be performed in the etching step, or an etching liquid can be sprayed onto the substrate.

As the resist removal pretreatment liquid for cutting at least a part of the chemical bonds in the resist, sulfuric acid, nitric acid,
A strong acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid or the like, or an alcohol solution or aqueous solution of an alkali metal hydroxide such as lithium, sodium or potassium can be used. Above all, the effect of sulfuric acid, which has a strong dehydrating action, is extremely large. A sulfuric acid concentration of about 20% by weight is effective, but
The effect is further enhanced when 0% by weight or more of concentrated sulfuric acid is used.
Particularly, for those having a poor peeling property, a good result can be obtained by using 80% by weight or more of concentrated sulfuric acid and treating at a temperature of 30 ° C. or more. The concentration of concentrated sulfuric acid may be 100% by weight. The treatment temperature is preferably room temperature or higher and about 60 ° C., and more preferably 30 ° C. or higher and about 60 ° C.

Further, in the case of the resist residue after the resist stripping treatment with the stripping solution, its thickness is not uniform, but is several μm.
It has decreased to the extent. However, the plating resist used in the present invention contains a compound or the like as a main component, which is liable to be broken due to a decomposition reaction of a chemical bond in the resist by a resist removal pretreatment liquid. For this reason, the deterioration of the resist due to the resist removal pretreatment progresses similarly even in the case of the unpeeled resist which is thicker than the resist residue. As a result, according to the present invention, the resist can be effectively removed without performing the resist stripping treatment with the stripping solution.

[0020]

It is presumed that the plating resist can be effectively removed by the present invention by the following actions. The acrylic compound, which is the main component of the plating resist used in the present invention, such as an ester bond of an acrylic acid ester or a methacrylic acid ester, is a bond that is more easily broken by a decomposition reaction than a carbon-carbon bond.

At the stage when the plating resist on the underlying metal is treated with the resist removal pretreatment liquid, the resist is altered and a part thereof is dissolved, but it is not completely dissolved, and it is also adhered to the substrate and peeled off. Difficult to do. However, when the water washing process is subsequently performed, the resist removal pretreatment liquid (for example, concentrated sulfuric acid) in the resist is replaced with water. Because the resist removal pretreatment imparts hydrophilicity to the resist, the amount of water invading into the resist increases as compared with the case of washing with water without the resist removal pretreatment. As a result, the resist removal pretreatment and the water washing treatment facilitate the progress of resist expansion and cracking. Due to the hydrophilicity imparted to the resist and the occurrence of cracks, the etching liquid is easily penetrated into the interface between the resist and the underlying metal, so that the resist can be easily peeled off.

By increasing the concentration of concentrated sulfuric acid, raising the temperature, and prolonging the immersion time in concentrated sulfuric acid, the above-mentioned change of the resist further progresses. In particular, when the adhesiveness of the resist is strong, it may be difficult to remove the resist only by etching, but the use of a mechanical treatment such as spraying or ultrasonic treatment can promote the peeling.

[0023]

EXAMPLE An example of the present invention will be described with reference to the sectional views of the conductor circuit and the base material shown in FIG. FIG. 1A is a cross section of an insulating plate 1 having a base metal layer 2. Copper is generally used for the base metal layer 2 in a printed wiring board. As the insulating plate 1, a glass epoxy laminated plate, a glass polyimide laminated plate, or the like can be used. These can use what is marketed as a copper clad laminated board. The base metal layer 2 is not limited to one layer, and a plurality of layers may be provided.

FIG. 1B shows a state in which the surface of the underlying metal layer 2 is roughened in order to improve the adhesion of the plating resist. In particular, when the conductor circuit shown in FIG. 1D, which will be described later, is formed by chemical copper plating, the resist is easily peeled off or swelled in the plating process, and thus an appropriate adhesion promoting treatment is essential. However, such surface roughening may be carried out as necessary and is not an essential step of the present invention.

Next, a plating resist pattern 3 is formed on the underlying metal layer 2 (FIG. 1 (c)). As a method for forming the plating resist pattern, there are a screen printing method, a photographic method using a photosensitive resist, and the like, but the photographic method is advantageous in forming a highly accurate pattern. For example, a dry film photoresist is laminated with a hot roll, a pattern image is exposed through a photomask, and then developed to form a resist pattern. As the photoresist, in addition to a dry film type photoresist, a liquid photoresist may be applied by a method such as screen coating, roll coating or curtain coating.

After that, the conductor circuit 4 is formed by plating (FIG. 1 (d)). In the case of a printed wiring board, copper plating is usually used for the conductor circuit 4. This is formed by electrolytic copper plating, chemical copper plating, or the like. Generally, electrolytic copper plating is widely used, but chemical copper plating is superior in terms of uniformity of plating thickness.

Next, the plating resist pattern 3 is stripped with a resist stripping solution (FIG. 1 (e)). Usually, a chlorine-based organic solvent such as dichloromethane is used for the solvent developing type resist, and an alkaline resist stripping solution is used for the alkali developing type resist for peeling and removing the resist. However, if the adhesion of the plating resist pattern 3 becomes high, the resist cannot be completely removed by these stripping treatments, and as shown in FIG. A resist residue 5 is formed. When the underlying copper foil is etched in this state, an etching residue 6 is formed under the resist residue 5 as shown in FIG. 3 (f) as a comparative example.
The processes from (a) to (e) of FIG. 3 shown as a comparative example are the same as the processes from (a) to (e) of FIG.

On the other hand, after the resist stripping treatment (see FIG.
(E)), and treatment with a resist removal pretreatment liquid (see FIG.
(F)) Further, the resist residue can be effectively removed by further treating with an etching solution for the underlying metal after washing with water (FIG. 1 (g)).

The plating resist pattern 3 contains, as a main component, a compound in which at least a part of chemical bonds in the resist is easily broken by the resist removal pretreatment liquid. Therefore, after the same processes as the processes from (a) to (d) of FIG. 1 are performed as shown in (a) to (d) of FIG. 2 and the conductor circuit 4 is formed (FIG. 2 (d)). The resist residue can be effectively removed even if the resist is treated with the resist removal pretreatment liquid without removing the resist with the resist removal liquid (FIG. 2 (e)) and further treated with the underlying metal etching liquid after washing with water. (Fig. 2 (f)).

In any case, thereafter, the underlying metal layer 2 other than the conductor circuit 4 is further removed by etching to form a fine wiring pattern having no defects such as etching residue (see FIG. 1 (h), Fig. 2
(G)). The etching of the underlying metal layer 2 does not have to be limited to the above two steps, and may be performed in one step after the resist treatment with the resist removal pretreatment liquid.

As the resist removal pretreatment liquid, a strong acid such as sulfuric acid, nitric acid, hydrochloric acid, hydrobromic acid or hydroiodic acid, or an alcohol solution or aqueous solution of an alkali metal hydroxide such as lithium, sodium or potassium is used. be able to. Above all, the effect of sulfuric acid having a strong dehydrating effect is extremely large. A sulfuric acid concentration of about 20% by weight is effective, but
The effect is further enhanced when 0% by weight or more of concentrated sulfuric acid is used. Especially for those having a poor peeling property, good results can be obtained by treating with 80% by weight or more of concentrated sulfuric acid at a temperature of 30 ° C. or more.

When the base metal layer 2 is treated with an etching solution to remove the resist residue 5, the removal efficiency of the resist residue can be improved by applying ultrasonic waves or spraying the etching solution. . Hereinafter, each step will be described in detail by giving some more specific examples.

Example 1 [Step 1] A substrate having a copper layer having a thickness of 12 μm and having a thickness of 0.
A 1 mm double-sided copper-clad glass-polyimide laminate was cut into a desired size, and the copper surface was brushed and polished.

[Step 2] After washing with water, in order to roughen the copper surface, it was immersed in a soft etching solution of composition (I) shown in Table 1 below at 30 ° C. for 1 minute.

[0035]

[Table 1]

[Step 3] Next, in order to further roughen the copper surface, a treatment liquid having the composition (II) shown in Table 2 below was used at 70 ° C. for 2 hours.
It was immersed for a minute to form an oxide film layer on the copper surface.

[0037]

[Table 2]

[Step 4] Then, after washing with water, the oxide film layer was reduced by immersing it in a treatment liquid having the composition (III) shown in Table 3 below at 45 ° C. for 1 minute.

[0039]

[Table 3]

[Step 5] Next, after washing with water, a nickel plating solution having a composition (IV) shown in Table 4 below at 30 ° C. was used.
Plating was performed for 6 minutes at a current density of 0.05 A / dm ² to form a thin nickel plating layer on the surface of the copper layer. In this case, the thickness of the nickel plating layer was 0.06 μm. Then, the substrate was washed with water to obtain a substrate in which nickel was plated on the surface-roughened copper.

[0041]

[Table 4]

[Step 6] Subsequently, after the substrate surface was sufficiently dried, a dry film photoresist having a photosensitive resin composition layer (thickness 35 μm) having the composition (V) shown in Table 5 below was laminated by a hot roll. did. At this time, the hot roll temperature was 110 ° C. and the laminating speed was 1 m / mi.
n. And

[0043]

[Table 5]

[Step 7] After being left to cool for about 5 minutes, a portion for forming a circuit is masked and exposed to an ultra-high pressure mercury lamp exposure apparatus at 100.
It was exposed to mJ / cm ² . Next, 1,1,1-trichloroethane was used as a developing solution, and the resultant was sprayed at about 25 ° C. for 2 minutes for development. As a result, the portion of the substrate surface where no circuit was formed could be masked with the plating resist.

[Step 8] Next, the soft etching solution having the composition (I) was applied for 2 minutes to remove the nickel film in the portion to be the circuit.

[Step 9] After washing with water, it was immersed in a chemical copper plating solution having the composition (VI) shown in Table 6 below at 70 ° C. for 12 hours to form a conductor circuit having a thickness of about 30 μm.

[0047]

[Table 6]

[Step 10] After plating, thoroughly wash with water. Then, after soaking the whole in a 3% aqueous solution of sulfuric acid for 2 minutes, a current density of 1 with a solder plating solution having the composition (VII) shown in Table 7 below.
Solder plating was performed at A / dm ² for 15 minutes.

[0049]

[Table 7]

[Step 11] Next, dichloromethane at 30 ° C. was sprayed on the substrate for 10 minutes to remove the resist on the substrate. However, the plating resist residue was adhered to almost the entire surface of the base copper foil in the portion other than the circuit.

[Step 12] This substrate was immersed in 95% by weight sulfuric acid at 40 ° C., which is a resist removal pretreatment liquid, for 5 minutes to cause dehydration decomposition reaction of the resist.

[Step 13] Next, the substrate was washed with water.

[Step 14] Further, etching was performed for 1 minute while applying ultrasonic waves in the soft etching solution of composition (I). As a result, the underlying copper foil was etched by about 0.8 μm. Further, this etching treatment removed all the resist residues from the surface of the underlying copper foil.

[Step 15] Next, the substrate was washed with water.

[Step 16] Further, the underlying copper foil on the portion other than the circuit was removed by etching with an etching solution having the composition (VIII) shown in Table 8 below. The etching rate of the underlying copper foil is 8 μm / min. Met.

[0056]

[Table 8]

On the substrate on which the conductor circuit is formed by the processes from step 1 to step 16 described above, there is no copper etching residue on the portion other than the circuit, and a highly accurate wiring pattern can be produced without defects. It was

Comparative Example 1 In Comparative Example 1, instead of performing Steps 13, 14, and 15 after Step 12, the substrate surface was rubbed with an acid resistant brush as shown in the prior art, and then Step 16 was performed. That is the case. Other than this, the same as in Example 1. As a result, the resist was removed in the areas where there is no wiring and in the areas where the wiring spacing is wide, but the resist is not completely removed during the resist and between the parallel wirings, and copper remains after etching. did. Also,
A circuit defect such as a pattern defect, which is thought to be caused by scratches caused by brushing, occurred.

Comparative Example 2 The substrate before the resist removal pretreatment of Example 1 is directly treated with the etching solution having the composition (VIII), that is, the steps 12 and 13 described above are not performed,
After the step 11, the process of the step 16 was directly carried out to try to etch the underlying copper foil in the portion other than the circuit. as a result,
Most of the resist residue remains on the surface of the underlying copper foil,
Further, that portion was left as a copper etching residue. As a result, many circuit defects occur such that the circuit interval becomes smaller than the design value and short circuits occur.

Example 2 The substrate after the resist removal pretreatment of Example 1 is washed with water as it is, and then treated with an etching solution having the composition (VIII), that is, after the step 12, the above steps 13 and 14 are performed. Instead, the steps 15 and 16 were carried out to attempt one-step etching of the underlying copper foil in the portion other than the circuit. As a result, there was no etching residue of copper on the surface of the substrate other than the circuit, and a highly accurate wiring pattern could be produced without defects.

<Comparative Example 3> The substrate after the resist removal pretreatment (Step 12) of Example 1 was treated with an etching solution having the composition (VIII) without being washed with water, and the underlying copper foil was etched except for the circuit. Tried. That is, after step 12,
Step 16 was performed. As a result, most of the resist residue remained on the surface of the underlying copper foil as it was, and further that part remained as copper etching residue. As a result, many circuit defects occur such that the circuit interval becomes smaller than the design value and short circuits occur.

<Examples 3 to 6> These examples were carried out to confirm the effect of the difference in the type of resist on the removal of the plating resist. That is, the plating resists shown in the composition (V) in Table 5 were prepared by using polymethylmethacrylate as the main component and by replacing only polymethylmethacrylate with polymethylacrylate, polymethacrylic acid, or polyacrylic acid. A resist was used. Except for the above points and the point that the nickel plating in step 5 was omitted, the same treatments as in Example 1 were performed to produce four types of evaluation substrates.

The evaluation of the manufactured substrate was carried out by observing the resist residue after step 14 and counting the number. After step 16, the number of copper etching residues (short circuit, excessive circuit width, etc.) due to under-etching and the number of circuit defects or thinning due to over-etching were similarly counted. Table 9 summarizes the results. As can be seen from Table 9, effective removal of the resist was possible by using the resist using the methacrylic acid resin or the acrylic acid resin.

[0064]

[Table 9]

Comparative Examples 4 to 6 Resists were prepared in which only polymethylmethacrylate, which is the main component of the plating resist shown in composition (V) in Table 5, was replaced with polyacrylonitrile, polybutadiene, or polystyrene. Except for the above points, the same processes as in Examples 3 to 6 were carried out to manufacture substrates.
After step 14, the substrate was evaluated in the same manner as in Examples 3 to 6 and as a result, the resist was found to have adhered to almost the entire surface of the substrate. Therefore, the number of various circuit defects was extremely large even after the process 16. The results are also shown in Table 1.

<Embodiment 7> In this embodiment, the process 1 of Embodiment 1 is performed.
This is a case where a 30 wt% sodium hydroxide aqueous solution is used in place of the 95 wt% sulfuric acid which is the resist removal pretreatment liquid shown in 2. The substrate was immersed in a liquid at 60 ° C. for 10 minutes.
Except for the above points, the same processing as in Example 1 was performed to manufacture a substrate. As a result, there was no etching residue of copper on the portion other than the circuit on the surface of the substrate, and a highly accurate wiring pattern could be produced without defects.

<Embodiment 8> In this embodiment, the resist stripping process of step 11 in Embodiment 1 is omitted. As the resist, a dry film photoresist having a photosensitive resin composition layer (thickness 35 μm) having the composition (X) shown in Table 10 below was used.

[0068]

[Table 10]

Except for the above points, the same treatment as in Example 1 was carried out to produce an evaluation substrate. Moreover, the number of resist residues and the number of circuit defects were evaluated in the same manner as in Examples 3 to 6. As a result, there was no etching residue of copper on the portion other than the circuit on the surface of the substrate, and a highly accurate wiring pattern could be produced without defects.

Example 9 In this example, the resist removal pretreatment liquid of Example 8 was replaced with the same 30 wt% sodium hydroxide aqueous solution as in Example 7. The substrate was immersed in a liquid at 60 ° C. for 10 minutes in the same manner as in Example 7, and thereafter the same treatment as in Example 8 was performed to produce a substrate. As a result, there was no etching residue of copper on the portion other than the circuit on the surface of the substrate, and a highly accurate wiring pattern could be produced without defects.

In each of the above examples, sulfuric acid was used as the strong acid of the resist removal pretreatment liquid, and sodium hydroxide aqueous solution was used as the alkali metal hydroxide solution.
Almost similar results were obtained using a strong acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid or a solution of an alkali metal hydroxide such as a solution of lithium or potassium.

[0072]

According to the present invention, the resist removal pretreatment,
By performing the water washing treatment, the plating resist can be efficiently removed, and the etching residue of the underlying metal due to the adhesion of the resist residue can be prevented. Moreover, the plating resist can be efficiently removed by performing the resist removal pretreatment and the water washing treatment without performing the stripping treatment of the plating resist with the chlorine-based organic solvent, thereby etching the underlying metal caused by the adhesion of the resist residue. You can prevent the rest. Therefore, in each case, a fine circuit without defects such as a short circuit can be formed.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a method for forming a conductor circuit according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a method for forming a conductor circuit according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a conventional method for forming a conductor circuit.

[Explanation of symbols]

 1 ... Insulating plate 2 ... Base metal layer 3 ... Plating resist pattern 4 ... Conductor circuit 5 ... Resist residue 6 ... Etching residue

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koji Yamamoto 1 Horiyamashita, Horiyamashita, Hadano, Kanagawa Pref., General Computer Division, Nitrate Manufacturing Co., Ltd. (72) Shiro Kobayashi 1 Horiyamashita, Hadano, Kanagawa (72) Inventor, Fujiko Yutani 7-1-1, Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory

Claims (8)

[Claims] 1. A step of providing a plating resist containing an acrylic compound as a main component in accordance with a wiring pattern on a base metal provided on an insulating plate, a step of forming the wiring pattern by plating, and a stripping solution for the plating resist. Peeling step, a step of treating the plating resist with a resist removal pretreatment liquid that cuts at least a part of chemical bonds in the plating resist, a step of washing the plating resist with water, and an etching step of etching the base metal. A method for forming a conductor circuit on a printed wiring board, comprising: 2. A step of providing a plating resist containing an acrylic compound as a main component in accordance with a wiring pattern on a base metal provided on an insulating plate, a step of forming the wiring pattern by plating, and a stripping solution for the plating resist. Peeling step, a step of treating the plating resist with a resist removal pretreatment liquid consisting of a solution of a strong acid or an alkali metal hydroxide,
A method for forming a conductor circuit on a printed wiring board, comprising: a step of washing the plating resist with water; and an etching step of etching the base metal. 3. A conductor circuit for a printed wiring board according to claim 1, wherein the acrylic compound is a methacrylic acid compound or an acrylic acid compound. Forming method. 4. The method for forming a conductor circuit on a printed wiring board according to claim 1, wherein the resist removal pretreatment liquid is sulfuric acid. Method. 5. A step of providing a plating resist containing an acrylic compound as a main component in accordance with a wiring pattern on a base metal provided on an insulating plate, a step of forming the wiring pattern by plating, and a chemistry in the plating resist. A conductor circuit of a printed wiring board, comprising a step of treating a plating resist with a resist removal pretreatment liquid for cutting at least a part of bonds, a step of washing the plating resist with water, and an etching step of etching the base metal. Forming method. 6. A step of providing a plating resist containing an acrylic compound as a main component in accordance with a wiring pattern on a base metal provided on an insulating plate, a step of forming the wiring pattern by plating, a strong acid or alkali metal water. A method for forming a conductor circuit on a printed wiring board, comprising: a step of treating a plating resist with a resist removal pretreatment liquid composed of an oxide solution; a step of washing the plating resist with water; and an etching step of etching a base metal. . 7. The method for forming a conductor circuit of a printed wiring board according to claim 5, wherein the acrylic compound is a methacrylic acid compound or an acrylic acid compound. Forming method. 8. The method for forming a conductor circuit on a printed wiring board according to claim 5, wherein the resist removal pretreatment liquid is sulfuric acid. Method.