JPH04196384A - High density printed board and manufacture thereof - Google Patents

Abstract

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

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a printed wiring board and a method for manufacturing the same, and in particular, a printed wiring board and method for manufacturing the same suitable for improving the reliability of through holes in high-density printed wiring boards. Regarding.

[Conventional technology]

(1) Conventional Example 1 The appearance of a typical example of a conventional printed wiring board is shown in FIG. 3 as a partially sectional perspective view. Copper plating 7 as shown
In the through-holes 2 of the printed wiring board formed by chisel, the beer strength in the tensile peel strength test is low, so bulges 15 are likely to occur on the inner walls of the through-holes 2 during various pretreatment processes. As a result, accidents such as connection failures occurred, resulting in problems with the reliability of the through-holes.

It has also been proposed to cover the copper-plated circuit pattern and through-hole conductor with nickel plating to create a two-layer structure of copper plating and nickel plating, but this does not solve the above problems. An example of a conductor having this type of copper-nickel 2N structure is disclosed in Japanese Patent Application Laid-Open No. 190792/1983.

(2) Conventional Example 2 For example, in the circuit formation method for high-density printed circuit boards having small-diameter through-holes of 0.5 mm or less, a solder plating method as shown in Figure 6 is used to maintain the reliability of the through-holes. Commonly used.

Hereinafter, a description will be given with reference to FIG. 6, which shows a schematic diagram of a circuit forming process using a solder plating method.

Step (a): Holes are drilled in the copper-clad laminate 1 and copper plating is performed to form through holes 2.

Step (b): A film-type photoresist 11 is laminated on the entire surface of the substrate, and a positive mask 1 with a circuit pattern drawn thereon is formed.
Exposure 10 using 2.

Step (C): A plating resist 14 having a pattern of photoresist 1 is formed by development.

Step (d): Perform the solder plating 13.

(e) Step: Peel off the plating resist 14 to expose the underlying copper.

(f) Step: Using the solder plating 13 as a resist mask, the exposed copper is removed by etching.

(g) The resist mask of the solder plating 13 is peeled off to form the circuit pattern 9.

[Problem to be solved by the invention]

However, in the circuit pattern forming method as explained in FIG. 6, as the pattern becomes ultra-fine (resolution of 50 mm or less), the conventional film-type photosensitive resist 11 becomes as shown in FIG. 7(a). As a result, resist resolution failure 23 occurs, resulting in problems such as dotting of adjacent resist patterns 11 and failure of resist adhesion 24, making it difficult to form high-density circuits.

On the other hand, in order to form a high-resolution fine line pattern, there is a method using an electrodeposition type photosensitive resist. When electrodeposition type photosensitive resist is used, as shown in Figure 7(b), it is thinner than film type photosensitive resist and has good adhesion to the copper foil surface, making it possible to form high-resolution fine line patterns. It is. However, in this type of pattern forming process, the inner wall of the through hole 2 must also be exposed, and in the case of a small diameter through hole, the through hole 2 coated with an electrodeposition type photosensitive resist 5 as shown in FIG. It is difficult for the foggy light 10 to be irradiated with sufficient light, and some parts are left unexposed. Therefore, as shown in step (c) of FIG.
Defects 8a occur in the electrodeposited photosensitive resist mask 8 in the through holes 2 formed by the development process, and the through hole defects are removed in the etching process by this defect mask 8a, as shown in FIG. 4(d). 7a occurs, which reduces the reliability of the through hole.

Japanese Patent Application Laid-Open No. 61-247090 discloses a method for forming a high-resolution thin line pattern without impairing the reliability of through-holes, but electrodeposition resists are used as solder plating resists, and solder plating resist patterns are Since this serves as an etching resist for the conductive film, the etching accuracy is the same as the conventional solder plating method shown in FIG. In other words, this method of forming a circuit pattern using an electrodeposition resist uses an electrodeposition resist in place of the photoresist (11) in step (b) of FIG.

Therefore, an object of the present invention is to solve the problems pointed out in Conventional Examples 1 and 2 above, and the first purpose is to improve the reliability of the conductor layer in the through hole and realize a high resolution fine line pattern. The second objective is to develop an improved high-density printed circuit board that can
The goal is to provide each.

[Means to solve the problem]

The first object is as follows: (1) In a printed wiring board consisting of a through hole in which a conductor layer is disposed on the inner peripheral surface and a circuit pattern is disposed on the surface of the board, the conductor layer in the through hole is durable. This is achieved by a high-density printed wiring board consisting of a double layer of a metal plating base layer having a copper etching liquid property and a copper plating integrally coated thereon up to at least the land portions of the circuit pattern.

The material of the metal plating base layer having copper etching liquid resistance is determined by the manufacturing process, that is, by the type of etching liquid used when etching the copper foil on the substrate to form a circuit pattern.

Usually, an alkaline etching solution is used, but in such cases, nickel plating, which is resistant to alkali, is practical and preferable.Also, in the case of acidic etching solutions, nickel plating, which is resistant to acids, such as tin plating, is preferred. Lead-based solder plating is preferred, and if it is resistant to both acidic and alkaline solutions, such as gold plating, it can be used in either case.

Further, the practical thickness of this base layer conductor is at least 0.
17s or more is preferable, more preferably '0.5 to 2-
To some extent.

Further, as long as it is a very thin copper plating of, for example, 2Q or less, practically about 1 to 15 pores, it may be present as a base for the metal plating having the above-mentioned copper etching liquid resistance.

Furthermore, it is desirable that a solder resist be coated on the circuit board except for the inside of the through hole and the land portion. This solder resist serves as a plating resist mask when copper plating is formed on the conductor from inside the through hole to at least the land portion, and also as an insulating protective film since it covers the surface circuit pattern.

The second purpose is to: (2) form a through hole in the copper-clad laminate; form a conductor layer in the through hole; and form a conductor layer on the substrate at the periphery of the opening of the through hole. A method of manufacturing a printed circuit board comprising a step of forming a circuit pattern including a land to be formed, the step of forming a conductor layer in the through hole is replaced with forming a metal plating base layer having resistance to copper etching liquid. After that, a circuit pattern is formed on the substrate by selectively etching the copper foil of the copper-clad laminate including the land formed around the through-hole opening, and from the metal plating base layer to at least the land. High-density printing is a process in which copper plating is integrally formed, and a conductor layer consisting of a double layer of the metal plating that is resistant to the copper etching liquid and the copper plating coated thereon is formed inside the through hole. This is achieved by a method for manufacturing a substrate.

Preferably, (3) a step of forming a through hole in the copper-clad laminate, a step of forming a conductor layer in the through hole, and a step of forming a land on the substrate at the periphery of the opening of the through hole. In the method of manufacturing a printed circuit board, the step of forming a conductor layer in the through hole is performed by forming a base conductor layer, such as nickel plating, that is resistant to an alkaline etching solution. rear,
A circuit pattern is formed on the substrate by selectively etching the copper foil of the copper-clad laminate including the land formed around the periphery of the through-hole opening with an alkaline etching solution, and a circuit pattern is formed by selectively etching the copper foil of the copper-clad laminate including the land formed around the periphery of the through-hole opening. A process of integrally forming copper plating up to at least the land, and forming a conductor layer consisting of a double layer of an alkali-resistant base conductor layer such as nickel plating and copper plating coated thereon in the through hole. This is achieved by a method of manufacturing a high-density printed circuit board consisting of: Also, (4)
, as a metal plating base layer having resistance to copper etching liquid as described in (3) above, forming a base conductor layer resistant to acid etching liquid such as solder plating, and forming it on the periphery of the through-hole opening on the substrate. This is achieved by a method for manufacturing a high-density printed circuit board, which includes the steps of selectively etching the copper foil of the copper-clad laminate including the lands to form a circuit pattern using an acidic solution as an etching solution. Furthermore, (5) as a metal plating base layer having resistance to copper etching liquid as described in (3) above, a step of forming a base conductor layer having resistance to acidic and alkaline etching liquids such as gold plating, Manufacturing of high-density printed circuit boards in which a circuit pattern is formed by selectively etching the copper foil of a copper-clad laminate, including lands formed around the openings of through-holes, using an acidic or alkaline etching solution as an etching solution. This is achieved by the method. Still more preferably, (6), when integrally forming copper plating from the inside of the through hole to at least the land part, as a pre-process of copper plating, on the circuit board excluding the inside of the through hole and the land part. This is achieved by the method for manufacturing a high-density printed circuit board according to any one of (2) to (5) above, which includes an additional step of coating with a solder resist. (7) After performing the step of forming a metal plating base layer having resistance to copper etching liquid on the entire surface of the substrate including the inside of the through hole, in the step of forming a conductor layer in the through hole, removing the metal plating that is resistant to copper etching liquid formed on the surface of the substrate by mechanical polishing;
The process of copper plating is to remain only in the through hole, and the process of applying copper plating is to coat the entire surface with photosensitive resist, expose it to light through a mask with a predetermined circuit pattern, and form an etching resist mask pattern. Then, the copper foil on the board is selectively etched using this resist mask pattern, the resist mask pattern is peeled off and removed to form a circuit pattern including lands, and then a copper-resistant etching solution is applied to the through hole. According to the method for producing a printed circuit board according to (2) above, which comprises a step of coating with copper plating from a metal plating base layer having a conductivity to at least the land of the opening, (8) a conductor layer is formed in the through hole. 5 After performing the step of applying a metal plating conductor layer having resistance to copper etching liquid, such as nickel plating, on the entire surface of the board including the inside of the through-hole, is removed by mechanical polishing and formed only within the through hole, and the copper plating process is performed by coating the entire surface with a photosensitive resist and exposing it to light through a mask with a predetermined circuit pattern drawn, and processing the pattern. An etching resist mask pattern is formed, the copper foil on the board is selectively etched using this resist mask pattern, the resist mask pattern is peeled off and removed to form a circuit pattern including a land, and then a circuit pattern is formed in the through hole. The above (2) is a step of coating copper plating from the conductive layer such as nickel plating to at least the land of the opening.
This is achieved by the printed circuit board manufacturing method described in ).

More preferably, (9) the method for manufacturing a printed circuit board according to (7) or (8) above, comprising the step of depositing and forming the metal plating having the copper etching liquid resistance to a thickness of at least 0.1 μm. 5 is achieved by.

(10) As the above-mentioned photosensitive resist, an electrodeposition type U-type resist is preferable, but a film-like resist can also be used depending on the purpose.

(11) As a pre-process of forming a metal plating base layer having copper etching liquid resistance, a thickness of 20 μm or less,
Preferably, a step of depositing chemical copper plating or electrolytic copper plating with a thickness of 1 to 15 μm may also be added.

[Effect]

When selectively etching the copper foil on the board to form a circuit pattern, the reliability of the through holes is maintained by the pre-formed metal plating base layer, such as nickel plating, which is resistant to copper etching liquid, and the surface circuitry is maintained. The pattern allows the use of electrodeposited resist, enables the formation of fine line patterns with high resolution, and is effective for the formation of high-density circuit boards having small-diameter through holes. For example, the reason for this will be explained in detail using FIG. 5, but the operational features of the present invention can be more easily understood by comparing it with FIG. 4, which was previously explained as a problem with the prior art. Good morning.

This figure 5 shows the process diagram of the printed circuit board, but since it is a schematic diagram created to explain the problem solving in the through hole, only the main process is shown and the process before and after 1 is shown. It's quite omitted.

First, in step (a), the through hole 2 of the copper-clad laminate is
The inside is coated with nickel plating 4 in advance, and step (b)
), the electrodeposition resist 5 is adhered to the entire surface of the substrate including the inside of the through hole 2, and in step (C), a resist mask pattern is formed through exposure and development using a mask (not shown) on which a circuit pattern is drawn. form 8. At this time, even if a resist defect 8a occurs in the small-diameter through hole 2 due to exposure irregularities, the present invention will not have any adverse effects due to the resist defect 8a, as can be seen in the first step. That is, in step (d), step (c
) The copper foil on the exposed surface of the board is selectively etched using the resist mask pattern 8 obtained in step 8 to form one circuit pattern. Also, since the nickel plating 4 has etching resistance against the copper foil etching solution, it is possible to form a high-resolution fine line pattern without impairing the reliability within the through hole 2.

After step (d), a step of applying solder resist to the entire surface except for the through holes and land portions 9a, and a masking effect of the second solder resist are used to selectively apply solder resist from the through holes to the land portions 9a. There is a step of integrally forming copper plating on the surface, which will be specifically explained in the next example section.

In addition, in the present invention, the nickel plating 4 coated inside the through hole 2 has excellent catalytic properties when a chemical copper plating process is used, and acts as a base conductor layer when electrolytically plated. It also has good adhesion to the membrane, which prevents blistering inside the holes and improves beer strength.

Furthermore, in the step (a) of FIG. 5, the through holes 2 of the copper-clad laminate are coated with nickel plating 4 in advance, but in the process leading up to this step, the entire surface of the board including the inside of the through holes 2 is coated with nickel. Plating 4 is formed, and the nickel plating 4 formed on the substrate surface is removed by polishing or other means, leaving only the inside of the through hole. Further, it is also possible to form the nickel plating 4 only in the through hole 2 by using phosphorography and plating technology instead of the polishing means. In any case, it is necessary not to form nickel plating on the substrate surface, or to remove it even if it is formed, and the reason for this is as follows.

In other words, if a conductive layer such as nickel plating that is resistant to the etching solution for the copper foil is formed on the copper foil on the surface of the board, this conductive layer will get in the way when etching the copper foil to form a circuit pattern. Therefore, as a pre-process, an etching process for forming a circuit pattern is also required for nickel plating. Naturally, this nickel plating is resistant to the copper foil etching solution, so a different etching solution is required, which is undesirable as it increases the number of steps.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure schematically shows the structure of a printed wiring board according to the present invention.

A nickel plating 4 with a thickness of 1 mm is formed as a base in the through hole 2 of the copper-clad laminate 1, and the surface thereof is coated with a copper plating 7 to form a two-layer structure. The land portion 9a of the copper foil circuit pattern 9 on the surface of the board is coated with copper plating 7 that is integrally formed with the copper plating 7 in the through hole 2, and the surface excluding the inside of the through hole 2 and on this land portion 9a is covered. The entire surface of the substrate including the circuit pattern 9 is covered with a solder resist 6.

FIG. 2 is a process diagram illustrating an example of a method for manufacturing a high-density printed circuit board that has not yet been developed.
The contents will be explained in order according to (1).

Step (a) Through-holes 2 are made at predetermined positions in the two-sided copper-clad laminate 1.

Step (b): A catalyst 3 (for example, Pd-3n type) for chemical nickel plating (hereinafter simply referred to as nickel plating) is applied.

Step (C): Nickel plating 4 is applied to the entire surface including through holes 2.

Step (d): The nickel plating 4 on the surface is removed by mechanical polishing.

Step (e): Electrodeposition type UV resist 5 is coated on the exposed copper foil and the nickel plating 4 in the through holes. As the electrodeposition type UV resist, "Eagle 2000J" manufactured by Spree Co., Ltd. was used, and the conditions for electrodeposition were 25 to 40°C, a current density of about 40 to 60 mA/dm, and a current application time of , until the current value reached the minimum.The film thickness of the electrodeposition type UV resist at this time was approximately 10 to 20 μm.

Step (f) 2 After alignment is performed using a negative mask with a predetermined circuit pattern drawn and brought into close contact, ultraviolet light with a wavelength of about 365 nm is applied at 150 to 200 m j using an exposure machine equipped with an ultra-high pressure mercury lamp. /al irradiation to photocure the surface circuit portion and through hole portion.

Thereafter, the uncured portion is dissolved and removed by the phenomenon.

The electrodeposition type UV resist remaining at this time becomes the etching-resistant resist 8 for forming the surface circuit pattern in the subsequent step.

Step (g): After dissolving and removing the exposed copper foil on the substrate surface that is not covered with the etching resist 8 using ferric chloride, cupric chloride, alkaline etching solution, etc., the etching resist 8 is peeled off. , a surface circuit pattern 9 is formed. At this time, even if a resist defect occurs in the resist 8 in the through-hole portion 2 due to insufficient exposure, in the present invention, the underlying nickel plating 4 has resistance to this copper etching solution, so the resist 8 in the through-hole 2 can be etched. Etching processing for forming a circuit pattern on the surface of the substrate is performed while the substrate is stably held.

Step (h) A commercially available solder resist 6 is applied to the entire surface of the substrate except for the varnish through hole portions 2 and the land portions 9a.

Step (i) A copper plating process that is commonly used is applied to the entire surface including the inner surface of the through hole 2 to a thickness of 10 to 30 μm.
m copper plating 7 is deposited to complete the printed wiring board. In other words, the copper plating 7 was integrally coated from the inner surface of the through hole 2 to the land portion 9a not covered with the solder resist 6 on the substrate surface, and a high-density printed circuit board having the structure shown in FIG. 1 was obtained.

As the mesh plating process, chemical copper plating is practical and desirable, but electrolytic plating can also be used.

In addition, as the photoresist in step (e), an electrodeposition type UV resist was used in this example, but this is not limited to an electrodeposition type UV resist. UV exposure source is light used in photosensitive resist and other raw conductor industries, etc.
It goes without saying that a resist, an electron beam resist using an electron beam as an exposure source, and the like are practical.

Note that the formation of the surface circuit pattern 9 by copper foil etching in step (g) above was performed using ferric chloride, ferric chloride IIPL, and an alkaline etching solution in this example.
Other well-known etching solutions can be used in the same manner. That is, instead of the alkaline etching solution used in this embodiment, an iron-based acidic etching solution such as ferric chloride may be used. However, in this case, the nickel plating 4 used as the conductor layer in the through hole 2 has no resistance to acid etching solution and will dissolve, so it must be replaced with another plating that does not dissolve, such as Pb-5n solder plating. There is a need.

Furthermore, if the nickel plating 4 is replaced by a conductive layer that is resistant to acids and alkalis, such as gold (Au) plating, it will not be affected by the copper foil etching solution. Such solder plating and gold plating can be easily formed by well-known chemical plating or electrolytic plating in the same way as nickel plating.

Further, in these embodiments, the base conductor layer 4 such as nickel plating inside the through hole 2 was formed directly on the hole of the board, but a thin copper plating of 20 mm or less may be formed in advance after drilling the through hole. According to this, the plating process when forming the conductor layer 4 such as nickel plating becomes easier. In other words, in the formation of the conductor layer 4, since this thin copper plating is present on the base, the catalyst application step can be omitted during chemical plating, and electrolytic plating can also be performed. However, this thin copper plating requires thickness restrictions, and 20. Exceeding this is not preferable as it causes the conventional bulging problem and has the opposite effect. Therefore, as mentioned above, it is desirable that the conductor has a minimum thickness of 20 um or less, more preferably 1 to 15 um as thin as possible.

〔Effect of the invention〕

As mentioned above, the printed circuit board of the present invention has a structure in which the base of the copper plating 7 in the through hole is coated with a metal plating 4 having good adhesion and resistance to copper etching liquid, such as nickel plating. The beer strength of the copper plating 7 is strong, and there is no blistering inside the hole.The reliability inside the through hole is greatly improved.

In addition, in the manufacturing process, a circuit pattern can be formed using a resist mask 5 while the inside of the through hole 2 is protected with a metal plating 4 that is resistant to copper etching liquid, such as nickel plating, as explained in FIG. For,
Even if a defective part 8a of the resist mask occurs in the through hole 2 due to insufficient exposure, the underlying metal plating 4, which is resistant to copper etching liquid such as nickel plating, is resistant to etching liquid for forming a circuit pattern. Therefore, it is possible to form a high-resolution fine line pattern without impairing the reliability of the through-hole.

[Brief explanation of the drawing]

FIG. 1 is a partially cross-sectional perspective view showing the appearance of a printed wiring board according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing the manufacturing process of a printed wiring board according to an embodiment of the present invention. Figure 3 shows
FIG. 4 is a partial cross-sectional perspective view showing the appearance of a conventional printed wiring board, FIG. 4 is a schematic diagram showing a circuit forming process using a conventional electrodeposition resist, and FIG. 5 is a through hole during circuit formation according to the present invention. FIG. 6 is an explanatory diagram of the circuit formation process by solder plating, and FIGS. 7(a) and 7(b) are a film-type resist and an electrodeposition-type resist, respectively. External view showing the state of pattern formation by
The figure is a schematic cross-sectional view showing in-hole exposure of a through hole when an electrodeposited resist is used. <Explanation of symbols> 1...Copper-clad laminate, 2...Through hole, 3...Catalyst, 4...Nickel plating. 5... Electrodeposition resist, 6... Solder resist, 7... Copper plating, 7a... Copper plating defect, 8... Etching resist, 8a... Resist defect, 9... Surface circuit pattern, 9a... Land portion, 1o... Exposure, ゛ 11... Film type photosensitive resist, 12...
・Positive mask (circuit pattern mask), 13...Solder plating, 14...Plating resist, 15...Bulge in hole, 23...Insufficient resist resolution, 24...Poor resist adhesion.

Claims (12)

[Claims] 1. In a printed wiring board comprising a through hole in which a conductor layer is disposed on the inner peripheral surface and a circuit pattern is disposed on the surface of the board, the conductor layer in the through hole is a metal plating base layer having copper etching liquid resistance. , and copper plating integrally coated thereon at least up to the land portions of the circuit pattern. 2. In a printed wiring board comprising a through hole with a conductor layer disposed on the inner peripheral surface and a circuit pattern disposed on the surface of the board, the conductor layer in the through hole is plated with nickel, and at least the circuit pattern is plated on the conductor layer in the through hole. A high-density printed wiring board consisting of a double layer of copper plating that is integrally coated down to the land area. 3. 3. The high-density printed circuit board according to claim 1, wherein the circuit board except the inside of the through hole and the land portion is coated with a solder resist. 4. A step of forming a through hole in a copper-clad laminate, a step of forming a conductor layer in the through hole, and a step of forming a circuit pattern including a land formed around the opening of the through hole on the substrate. In the method of manufacturing a printed circuit board, the step of forming a conductor layer in the through hole is performed by forming a metal plating base layer having copper etching liquid resistance on the substrate, and then forming a conductor layer on the periphery of the through hole opening on the substrate. A circuit pattern is formed by selectively etching the copper foil of the copper-clad laminate including the land to be formed,
Copper plating is integrally formed from the metal plating base layer to at least the land, and a double layer of the metal plating having copper etching liquid resistance and the copper plating coated thereon is formed in the through hole. A method of manufacturing a high-density printed circuit board, which comprises a step of forming a conductor layer. 5. A step of forming a through hole in a copper-clad laminate, a step of forming a conductor layer in the through hole, and a step of forming a circuit pattern including a land formed around the opening of the through hole on the substrate. In the method of manufacturing a printed circuit board, the step of forming a conductor layer in the through hole is performed after forming a nickel plating base layer.
A circuit pattern is formed on the substrate by selectively etching the copper foil of the copper-clad laminate including lands formed around the through-hole openings, and copper plating is applied from the nickel plating base layer to at least the lands. A method for manufacturing a high-density printed circuit board, which includes a process of integrally forming a conductor layer consisting of a double layer of nickel plating inside the through hole and copper plating coated thereon. 6. When integrally forming copper plating from the inside of the through hole to at least the land portion, a step of coating the circuit board with a solder resist excluding the inside of the through hole and the land portion is added as a pre-process of copper plating. 6. The method for manufacturing a high-density printed circuit board according to claim 4 or 5. 7. In the process of forming a conductor layer in the above-mentioned through holes, the process of forming a metal plating base layer that is resistant to copper etching liquid is performed by applying metal plating that is resistant to copper etching liquid on the entire surface of the board including the inside of the through hole. After the formation, the metal plating that is resistant to copper etching liquid formed on the surface of the substrate is removed by mechanical polishing, and the metal plating that is resistant to copper etching liquid is formed only in the through hole. The process involves coating the entire surface with a photosensitive resist, exposing it to light through a mask with a predetermined circuit pattern drawn thereon, forming an etching resist mask pattern, and using this resist mask pattern to etch the copper foil on the substrate. After selectively etching and peeling and removing the resist mask pattern to form a circuit pattern including lands,
5. The method of manufacturing a printed circuit board according to claim 4, further comprising the step of coating the nickel plating formed in the through hole with copper plating from the nickel plating formed in the through hole to at least the land of the opening. 8. In the process of forming a conductor layer in the above-mentioned through-hole, the process of applying nickel plating is performed by forming nickel plating on the entire surface of the board including the inside of the through-hole, and then mechanically polishing the nickel plating formed on the surface of the board. The copper plating process is performed by coating the entire surface with a photosensitive resist, exposing it to light through a mask with a predetermined circuit pattern, and etching it. A resist mask pattern is formed, a copper foil on the substrate is selectively etched using this resist mask pattern, and the resist mask pattern is peeled and removed to form a circuit pattern including a land, and then a circuit pattern including a land is formed in the through hole. 6. The method of manufacturing a printed circuit board according to claim 5, further comprising the step of covering at least the land of the opening with copper plating from the nickel plating. 9. The plating conductor layer in the through hole is at least 0.
．． The method for manufacturing a printed circuit board according to claim 7 or 8, further comprising a step of forming the printed circuit board until the thickness reaches 1 μm. 10. 9. The method of manufacturing a printed circuit board according to claim 7, wherein the photosensitive resist is an electrodeposition type UV resist. 11. 9. The method of manufacturing a printed circuit board according to claim 7, wherein the photosensitive resist is a film resist. 12. 11. The method of manufacturing a printed circuit board according to claim 5, 6, or any one of claims 8 to 10, further comprising adding a pre-process of depositing chemical copper plating or electrolytic copper plating to a thickness of 20 μm or less before applying the nickel plating.