JPS62273795A - Printed wiring board and manufacture of the same - 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] Detailed Description of the Invention Anti-Blood! The present invention relates to a printed wiring board and a method of manufacturing the same, and more particularly to a through-hole printed wiring board, a single-sided printed wiring board, and a method of manufacturing them.

Conventional technology and its problems Conventionally, printed wiring boards have been manufactured by various methods, but taking a through-hole printed wiring board as an example,
It is typically manufactured by the following method. That is,
A hole is drilled in a copper-clad laminate, the entire surface including the inner wall of the hole is treated with a catalyst, and the entire surface is subjected to electroless copper plating and, if necessary, electrolytic copper plating to form a copper plating layer on the inner wall of the hole, Next, in order to protect the copper plating layer formed on the inner wall of the hole, the hole is filled with a filler for filling the hole, and a pattern is formed using an etching resist or a pattern is formed by a tenting method. In this method, after applying a resist, all exposed copper is dissolved and removed by etching.

This method requires an extremely large number of steps and is complicated. Moreover, the copper foil originally provided on the copper-clad laminate and the copper plating layer that was subsequently applied by plating are all removed by etching except for the circuit pattern, so most of the copper is wasted. In addition to this, there are problems in terms of pollution control measures such as wastewater treatment. In addition, there is a problem of undercut during etching, making it difficult to thin the circuit, and the circuit accuracy is poor.

On the other hand, in order to omit etching and reduce the number of steps,
Other manufacturing methods have also been developed. This method involves drilling a hole in a laminate without copper foil, subjecting the entire surface to catalyst treatment, forming a pattern using negative resist, and applying electroless copper plating to the inner wall of the hole and the circuit area. This is a so-called additive method in which the resist is formed, the resist is removed, and the exposed catalyst treatment layer is removed. However, this method requires a special plating bath to improve the adhesion between the copper plating layer and the substrate, and the copper plating tends to precipitate in areas other than where it is needed, making it difficult to form fine patterns. There are problems such as:

Since the circuit pattern of the printed wiring board obtained by any of the above methods is formed in a convex manner on the surface of the substrate, there are the following drawbacks. In other words, circuit patterns that are formed in a convex manner tend to be damaged or disconnected due to external forces in the lateral direction, and this tendency is especially serious in recent years as there has been a demand for a reduction in circuit width (thinner lines). This is a disadvantage. In addition, when increasing the current carrying capacity of wiring, it is necessary to increase the circuit width or increase the height of the copper plating layer of the circuit pattern, but increasing the circuit width goes against the demand for thinner lines. On the other hand, increasing the height of the copper plating layer has the drawback of becoming weaker against external forces as described above. In addition, when surface mounting a = 6-chip, an adhesive is applied between a plurality of conductors that are formed to protrude convexly from the surface of the substrate,
The chip is fixed, but if the amount of adhesive applied and the adhesive strength (especially the desired adhesive strength) are not carefully controlled, the chip may fall off after the actual device is installed.Even after the adhesive hardens, it can easily fall off with a slight external force. There are problems such as it may fall off.

Means for Solving the Problems The present inventor has conducted extensive research in order to eliminate various drawbacks of the above-mentioned conventional printed wiring boards and methods of manufacturing the same. In the process, they came up with the idea of forming a recess in the base body corresponding to the circuit pattern and providing a conductor within the recess. However, it is not necessarily easy to put this idea into practice, and the inventors have conducted further studies. As a result, a substrate with recesses and holes corresponding to the circuit pattern is molded from resin using a mold, and an activation treatment is selectively performed only on the inner wall surfaces of the recesses and holes to deposit a conductor. It has been found that a desired through-hole printed wiring board can be obtained. The inventors have also discovered that a single-sided printed wiring board without through holes can be manufactured by molding a substrate with recesses as described above, selectively performing activation treatment only within the recesses, and depositing conductors. . The present invention was completed based on this new knowledge.

The present invention provides (a) a thermosetting or thermoplastic resin substrate;
(b) a hole formed through the base, (c) a recess formed in the base corresponding to the circuit pattern, (d) a conductor deposited on the inner wall of the hole by plating, and (e
) Provided is a printed wiring board characterized in that a conductor is deposited in the recessed portion by plating so as to be at the same level as the surface of the substrate or at a level lower than the surface of the substrate.

Furthermore, the present invention provides the following features: a) forming concave portions and holes corresponding to the circuit pattern from a thermosetting or thermoplastic resin using a mold equipped with pins for forming convex portions and holes corresponding to the circuit pattern; a step of molding a base body provided with the concave portion and “
A step of selectively applying activation treatment for electroless plating only to the inner wall surface of the hole, and c) a step of depositing a conductor only in the recess and on the inner wall surface of the hole by plating. The present invention provides a method for manufacturing a printed wiring board with characteristics.

Furthermore, the present invention includes a) a step of molding a base body having concave portions corresponding to the circuit pattern from a thermosetting or thermoplastic resin using a mold having convex portions corresponding to the circuit pattern; A printed wiring board characterized by comprising a step of selectively applying activation treatment for electroless plating only to the recessed portions, and c) a step of depositing a conductor only within the recessed portions by electroless plating. The present invention provides a method for manufacturing.

Hereinafter, with reference to the drawings showing one embodiment of the present invention, 9-1 The present invention will now be explained.

FIG. 1 shows a substrate (1) constituting the printed wiring board of the present invention.
). The base (1) includes:
A recess (4) corresponding to the circuit pattern is provided.

In addition, in the case of a through-hole printed wiring board, a hole (6) is provided in addition to the recess (4), and if a land is provided around the hole (6), the land is provided around the hole (6). A land forming recess (5) is provided. The base (1) is
It is molded from thermosetting or thermoplastic resin using a mold. As the thermosetting or thermoplastic resin mentioned above, a wide range of resins can be used without any particular restrictions as long as they can be molded. Those that give body are preferred.

With such resins (), for example, heat-curable resins such as diallyl phthalate resin, polyether sulfone (P
ES), polyetheretherketone (PEEK),
Aromatic polyester resin, (trade name "Econol" etc.)
, polysal 7one (Psi), polyphenylene sulfide (PPS), and other thermoplastic resins can be preferably used.

If necessary, reinforcing materials such as glass fibers and carbon fibers can be oriented in these resins. Among these resins, in particular, those having a heat distortion temperature (under a load of 18, 6 Kl/7) specified by ASTM D-648 of about 175
Heat resistance above ℃, especially around 200-300℃, UL94
Passes V-O as specified in
Particularly preferred is one having an electrical insulation property of about m.

The molds for molding these resins include a mold piece (2) as shown in FIG. Mold pieces (not shown) are provided, and at least one of the mold pieces is provided with a protrusion (3) corresponding to the circuit pattern on a surface providing a cavity for molding the base (1). It is something. Further, (7) in FIG. 2 is a convex part for forming a land in the case of a through-hole printed wiring board, and corresponds to the four parts (5) for forming a land in FIG. In this specification, in the description related to a through-hole printed wiring board with a land, the land is a part of the circuit pattern, so unless otherwise specified, "a convex part corresponding to one circuit pattern" and "a convex part corresponding to a circuit pattern" are used. The term "corresponding recesses" shall also include the above-mentioned land-forming protrusions and land-forming recesses, respectively. Furthermore, in this specification, the term "hole" includes not only a normal through hole but also a pie-7 hole.

The convex portion (3) corresponding to the circuit pattern on the mold column is
It can be manufactured by known methods such as mechanical cutting.

However, since the above-mentioned convex portion corresponds to the circuit pattern of a printed wiring board, it usually has a thickness of about 20 to 90 μm.
Mechanical cutting, etc., although not impossible, involves a considerable amount of time and cost. The present inventor succeeded in manufacturing the above-mentioned mold piece (2) using a plating technique. That is, as shown in FIGS. 7 to 10, a photosensitive resin film (22) is used on the metal plate (20) for forming the mold piece (2) to correspond to the circuit pattern of the printed wiring board. The exposed and developed metal plate surface is exposed and developed, a metal plating layer (24) is formed on the exposed metal plate surface to a required height, and then the exposed and developed photosensitive resin film is This is a method to remove.

As the metal plate (20), iron or iron alloy plate has high strength and
Although it is preferable in terms of cost, etc., there is no particular restriction as long as it has wear resistance and strength as a mold and has adhesion to the metal plating layer.

As the photosensitive resin film (22), there is no particular restriction and a wide range of materials can be used as long as it can form a plating resist (22a) that is resistant to the plating bath for forming the metal plating layer after exposure. All such photosensitive resins are known, and for example, a methacrylate-based ultraviolet-sensitive film, a coating film of methacrylate-based ultraviolet-sensitive ink, etc. can be used.These resins can be formed into a film on a metal plate according to a known method. Alternatively, the film-like resin is pressure-bonded onto a metal plate.The thickness of these photosensitive resin films ranges from approximately the same height as the height of the convex portion (3) of the mold piece (2) to approximately twice that height. Generally, the thickness of the photosensitive resin film is 25 mm.
The thickness may be about 100 μm, preferably about 40 to 100 μm. Next, the photosensitive resin film is exposed and developed in a manner corresponding to the circuit pattern of the printed wiring board, and the exposure and development method may be an optimal method commonly used for the photosensitive resin film used. In this way, as shown in FIG. 8, the plating resist (2
2a) and the surface of the metal plate (20) is exposed.

Next, a metal plating layer (24) is formed on this exposed surface. The metal plating layer (24) is the metal plate (24).
0), and has hardness and abrasion resistance that can withstand multiple molding operations. When an iron or iron alloy plate is used as the metal plate (20),
Typically, the metal plating layer (24) is nickel plating, cobalt-nickel alloy plating with a cobalt content of about 3 to 10% by weight, iron-nickel alloy plating with an iron content of about 3 to 10% by weight, or hard chromium plating. It is preferable to form it by etc. These plating methods may be carried out according to conventional methods using various known plating baths. For example, when performing electroplating, the metal plate is degreased, washed with water,
After performing activation treatment such as immersion in acid and pretreatment such as washing with water, it may be immersed in a plating bath and electroplated. In addition, when performing electroless plating, after the above-mentioned pretreatment, an activation treatment such as a palladium-tin mixed catalyst is performed, and then the plate is immersed in a plating solution. Typical examples of the plating solution include, but are not limited to, those listed below.

b) Nickel-cobalt alloy plating bath composition Nickel sulfate 240 ~ 280g/9 Nickel chloride
45 ~5097Q cobalt sulfate
10 to 20g/Q ferric acid 30
~409/Q Sodium formate 40 ~5
0'j/Qp)l 4.0 ~
4.5 Bath temperature 55-60℃ Cathode current density 3-8A/dm20) Electronickel plating bath Nickel chloride 15-30g/Q Nickel sulfamate 300-450(j/Q
30 ~459/Qpl-13,
0 to 5.0 16 Temperature 25 to 70°C Cathode current density 1 to 5 A/dm2 C) Electrolytic nickel plating bath Nickel sulfate 240 to 450 g/Q Nickel chloride 38 to 60 g/Q 9
30 ~ 50g/Q brightener
Appropriate amount pH 2,8 to 5,5 Temperature 40 to 70°C Cathode current density 1 to 5 A/dm2 2) Acidic electroless nickel-phosphorus plating bath nickel 20 to 30
g/Q Sodium hypophosphite 10-20g/Q Sodium citrate 10-30g/Q Additive
Trace amount 1) l-(4-6 Temperature approx. 90℃ e) Nickel-iron alloy plating bath = 17- Nickel sulfamate 200-700g/Q Nickel chloride 1-50g/Q Metallic nickel
35-12097Q sulfamic acid
Iron 0.1-30g/Q boric acid
30 to 40 (j/Q stabilizer 0.1
~30g/Q (oxycarboxylic acid) Sodium lauryl sulfate 0~2g/Q temperature
25-70℃ cathode current density
1 to 50 A/dm2 In this way, as shown in FIG. 9, a metal plating layer (24) is formed to form convex portions (3). The height of the convex portion (3) can be determined as appropriate depending on the current carrying capacity of the circuit pattern of the printed wiring board to be manufactured, etc., but is usually about 20 to 90 μm, preferably about 35 to 70 μm. . Next, as shown in FIG. 10, the photosensitive resin film is removed by a conventional method.

The mold piece (2) thus obtained is combined with another mold piece (not shown) for forming the other surface of the substrate (1) of the printed wiring board to form a mold.

When the resin is molded using a mold made by combining two mold pieces each having a protrusion (3) corresponding to the circuit pattern on the cavity providing surface, the circuit pattern is formed as shown in FIG. Base body (1) with corresponding recesses (4) on both sides
is obtained. When molding is performed using a mold having a mold piece (2) having a convex portion (3) corresponding to the circuit pattern on the cavity providing surface and a mold piece having a smooth cavity providing surface, the mold piece corresponds to the circuit pattern. A base body having a recess (4) on only one side is obtained.

Furthermore, through holes (6) can also be provided in the base (1) by molding. For example, a cylindrical pin (not shown) is placed on the land forming convex portion (7) of the mold piece (2) in FIG.
is set upright, a recess into which the tip of the pin can be inserted and removed is provided in the other mold piece using, for example, a drill, and with the tip of the pin fitted into the recess, molten resin is injected and molded. Bye.

The above-described molding can be performed by molding a molten resin by injection molding, injection compression molding, vacuum forming, or the like, or by pressing a resin plate. The cavity for molding the substrate (1) provided by the above mold is approximately equal to the thickness of the printed wiring board (approximately 0.2 to 10 m), so it corresponds uniformly and faithfully to the circuit pattern within such a flat cavity. To obtain the substrate (1) with the recesses (and holes), after injecting the molten resin into the cavity, the substrate (
It is preferable to perform molding by applying pressure from a direction perpendicular to the surface on which the circuit pattern is formed in 1). Such molding can be advantageously carried out using, for example, a vertical molding machine. As the molding conditions, it is advantageous to adopt the optimum conditions for the resin used.

Thus, the hole (6) and the recess (
4) is obtained. Incidentally, the base body (1) for a through-hole printed wiring board can also be obtained by simply using two mold pieces to obtain a molded body having only a concave portion and drilling holes therein, without using the above-mentioned pins. Can be done.

Next, in the present invention, the recess (4) of the base (1) is
), or in the case of a through-hole printed wiring board, the bottom and sides of the recess (4) and the hole (6).
Activation treatment for electroless plating is selectively applied only to the inner wall surface of the plate. Hereinafter, a description will be given with reference to FIGS. 3 to 6, taking a through-hole printed wiring board as an example. FIG. 3 is a sectional view taken along line AA' in FIG. 1, and it is assumed that a recess is formed on the back surface of the base (1) shown in FIG. 1 symmetrically with the front surface.

In the selective activation treatment, for example, the entire surface of the substrate (1) including the inner wall surface of the pores (6) is treated with a catalyst commonly used for electroless plating such as a palladium-tin mixed catalyst. Then, as shown in FIG. 3, catalyst nuclei (8) are attached. Thereafter, the front and back surfaces of the substrate (1) are uniformly mechanically polished to remove catalyst nuclei on the front and back surfaces. This polishing can be carried out using conventional equipment such as, for example, a surface polisher. In this way, as shown in FIG.
) and the bottom and side walls of the recess (4).

In this way, the inner wall surface of the hole (6) and the bottom surface and side wall surface of the recess (4) are selectively activated.
Next, as shown in FIG. 5, electroless plating is performed to deposit a conductive metal (10) only on the selectively activated portions. As the electroless plating mentioned above, electroless copper plating is usually used, but depending on the intended use of the printed wiring board, electroless plating of other conductors, such as gold, silver, nickel, and nickel-based alloys, may be used. It can also be adopted.

Furthermore, depending on the circuit pattern, it is also possible to use electroless plating followed by electroplating.

When forming a conductor by electroless copper plating, various known plating baths for thickening can be used as the electroless copper plating bath. For example, as a typical example, one having the following composition is preferable. Can be used.

Cu2” 1.0 ~ 2.0 (j/
QEDTA 2.5 ~30g/Q
Paraformaldehyde 4 to 6 Additive Microstatic pH 11.8 to 12.2 Temperature 58 to 62°C The lower limit of the thickness of the conductor (10) is The thickness is such that the necessary current carrying capacity can be obtained, and the upper limit thereof is preferably the height of the recess (4) after the polishing process for the selective activation process. If necessary, after forming the conductor (10), the front and/or back surfaces of the obtained printed wiring board may be uniformly polished using, for example, a surface polisher to improve the smoothness of the front and/or back surfaces of the printed wiring board. It can also be improved further.

In this way, the sixth cross-sectional view taken along the line BB' in FIG.
As shown in the figure, the height of the surface of the conductor (10) is
1), and similarly, in the case of a through-hole printed wiring board, the height of the periphery of the hole (6), for example, the land portion, is also not more than the same height as the surface of the substrate. Therefore, in the present invention, a printed wiring board having a planar pattern or a printed wiring board having a circuit pattern buried below the surface of the substrate can be obtained.

The through-hole printed wiring board has been described above as shown in FIGS. 3 to 6, but a single-sided printed wiring board without through holes can also be produced in exactly the same way as above by using a base having a recess (4) on one side. By selectively activating only the bottom and side surfaces of the recess (4) and electroless plating,
It can be manufactured by performing a step of depositing a conductor only in the recess (4).

The printed wiring board thus obtained is made into a product through conventional manufacturing steps such as washing with water, drying, solder resist treatment, terminal plating, leveling treatment, and contour processing according to conventional methods.

R plate ■Four pots As detailed above, the printed wiring board of the present invention is made by molding a base body having a concave portion on one side corresponding to a circuit pattern from a resin, or by molding a base body having a concave portion corresponding to a circuit pattern on one side, or having a hole and a hole corresponding to a circuit pattern on both sides. A substrate with recesses is molded from resin, or a substrate with recesses corresponding to the circuit pattern on both sides is molded from resin, and then holes are punched, and then in the case of a single-sided print 1 to wiring board, only the inside of the recess is formed. In addition, in the case of a through-hole printed wiring board, only the inside of the recess and the inner wall surface of the hole are selectively activated, and finally the conductor is deposited only inside the recess and the inner wall of the hole by electroless plating, which is an extremely small number of steps. It can be manufactured through the process.

In addition, unlike conventional methods, conductor patterns are not formed by etching, which saves conductor metals such as copper, reduces the burden of pollution prevention such as wastewater treatment, and eliminates the problem of undercuts. Since there is no noise, the circuit accuracy is high. Furthermore, in the past, it was necessary to form a pattern on each substrate, and each pattern-forming treatment had to be performed, such as photosensitive resin film formation, exposure, development, film peeling, etc., but the present invention So, after creating the base mold,
Patterns can be formed using resin molding, an extremely efficient method, and the reproducibility of patterns is improved. Moreover, since the printed wiring board of the present invention has conductors embedded therein, defects due to contact between the conductors can be prevented.

Further, in the printed wiring board of the present invention, since the conductor of the circuit pattern is deposited and formed in the recess formed in advance in the base, the adhesion between the conductor and the inner surface of the recess is extremely high.

In addition, the conductors of the circuit pattern are in close contact with the three sides of the concave part of the base and the bottom, and are at the same level or lower than the base surface, so there is little risk of damage or disconnection due to external force. do not have.

Further, as described above, since the surface of the printed wiring board is uniform and has no irregularities, the chips can be reliably bonded with an adhesive when surface mounting the chips.

Further, since the printed wiring board of the present invention has a smooth surface pattern, it is easy to stack a plurality of printed wiring boards and apply it to the inner layer of a multilayer wiring board, and in particular, it is possible to suppress the occurrence of voids in the prepreg.

Further, the number of steps for manufacturing a circuit board for a rotary switch that requires a smooth surface can be reduced considerably.

Furthermore, by adjusting the height of the convex portion (3) corresponding to the circuit pattern of the mold used in the present invention, the depth of the concave portion (4) and therefore the thickness of the conductor (10) can be changed. Therefore, the current carrying capacity of the circuit can be changed without changing the circuit width, which is particularly advantageous for thinning the circuit.

The present invention will be explained in more detail with reference to Examples below. Note that the reference example shows an example of manufacturing a mold.

Reference example 1 Mold manufacturing Normal mold iron material (5501 dimensions 300#llllX3
00m> was polished smooth and given a lapping finish. A 70 μm thick acid-resistant photosensitive resin film (dry film for methacrylate plating resist) is applied to this finished surface.
was laminated.

Next, using the wiring circuit positive film, UV exposure and development were performed to form a plating resist and expose the surface of the iron material for the mold in correspondence with the circuit pattern.

Thereafter, electrolytic nickel plating of 70 μm was applied to the exposed surface using a nickel sulfamate plating bath. The composition of the nickel sulfamate plating bath used is as follows.

Nickel chloride 30g/Q Nickel sulfamate 300g/Q crawling M
30 g/Q pH 3.5 to 4.5 Temperature 25 to γ0° C. Cathode current density 3 A/dm2 Next, the remaining plating resist was removed to obtain a mold piece with convex portions corresponding to the circuit pattern. .

Drilling holes with a diameter of 0.86 in the order of erecting pins for forming through-holes in the convex portions for forming lands in the circuit of this mold piece,
A steel pin with a diameter of 0.85mm and a length of 6# was embedded and fixed by caulking.

On the other hand, a hole with a diameter of 0.86 m was provided in the land-forming convex portion of the other mold piece obtained in the same manner as above at a position corresponding to the embedded pin to receive the tip of the pin.

In this way, the mold consists of two mold pieces, each having a convex portion corresponding to the circuit pattern, one having a pin for forming a through hole embedded in it, and the other having a hole for receiving the tip of the pin. I got the mold.

Example 1 Using the mold obtained in Reference Example 1 above, thermoplastic polyether sulfon (PES) resin was molded using a vertical injection compression molding machine to obtain a mold with a thickness of 1.67 mm and 1 dimension of 3001111+1.
Ten substrates of X300JII11 were prepared. The molding conditions are as follows.

Supply hopper temperature 330℃ Cylinder nozzle temperature 350℃ Mold temperature 140℃ Injection pressure 1400 to 5F/cm screw back pressure 70 to 9/cat holding pressure
700Kfl/cM screw rotation speed
5 Or, p, m Cycle time: 30 seconds Injection speed: Medium speed The thus obtained substrate was dried at 160° C. for 3 hours. The obtained substrate has a depth of 7 on both sides corresponding to the circuit pattern.
It has a recess of 0 μm and a through hole of 0.86 s in diameter.

After degreasing and surface roughening, the entire surface of this substrate was activated with a palladium-tin mixed catalyst, and then the front and back surfaces of the substrate were mechanically polished with a surface polisher to a uniform thickness of 35 μm on each surface. The catalyst cores on the front and back surfaces were removed by polishing, leaving the catalyst cores only in the recesses and on the inner walls of the holes.

Next, in an EDTA bath having the following composition, electroless copper plating was applied at 35 μm tM on the inside of the recess where the catalyst core remained and on the inner wall of the hole.
Shita.

EDTA bath composition Cu2+ 1.0g/QEDTA
30g/Q paraformaldehyde
59/Q Additive: Trace amount pl-112.0 Temperature: 60°C In this way, a flat printed wiring board was obtained. In addition, in order to manufacture a finished printed wiring board, terminal plating,
Solder resist, Tsulder leveler processing, printing of marks,
Conventional product manufacturing processes such as external shape processing are performed, but in this example, the printed wiring board obtained through the above steps was used as a specimen, and thickness measurement, continuity test, and thermal shock test (high temperature immersion) were conducted. I did it. As a result, the thickness is 1.6
All values were within 0#1I11±0.05711111, conduction was normal and there were no disconnections or other abnormalities, and the S layer resistance of the through hole portion was also good at 0.25 mΩ or less. 260℃ with oil - Trifrene (20℃
JIS except for 10 thermal cycles between ±15℃)
After testing in accordance with C5012, a cross-sectional examination of the through-hole portion was performed, but no abnormalities such as corner cracks or peeling were observed.

Thus, in all tests, it was recognized that the board was good as a printed wiring board.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a part of the base of a printed wiring board according to one aspect of the present invention. FIG. 2 is a perspective view showing a part of a mold piece for forming a substrate for a printed wiring board according to one aspect of the present invention. 3 to 5 are process diagrams showing a method for manufacturing a through-hole printed wiring board according to the present invention, and FIG. 6 is a sectional view taken along line B-8' in FIG. 5. 7 to 10 are process diagrams showing a method for manufacturing the mold piece shown in FIG. 2. (1)...Base (2)...Mold piece (3)...Convex portion (4)...Concave portion (5)... ... Concavity for land formation (6) ... Hole (7) ... Protrusion for land formation (8) ... Touch IjX nucleus (10) ...・Conductor (20)...Metal plate (22)...Photosensitive resin (24)...Metal plating layer (and above) Figure 3 Figure 4 Figure 5 ! t, B &1! t f7 l9ov Figure 10

Claims (5)

[Claims] (1) (a) A base made of thermosetting or thermoplastic resin, (b) A hole formed through the base, (c) A recess formed in the base corresponding to the circuit pattern, (d ) a conductor deposited on the inner wall of the hole by plating, and (e) a conductor deposited in the recess by plating so as to be at the same level as or at a lower level than the base surface. A printed wiring board characterized by comprising: (2) (a) A substrate made of thermosetting or thermoplastic resin; (b) a recess formed in the substrate corresponding to the circuit pattern; and (c) a surface formed by plating into the recess, which is the same as the surface of the substrate. 1. A printed wiring board comprising a conductor deposited at a level or at a level lower than the surface of a substrate. (3) A) A base material with recesses and holes corresponding to the circuit pattern made of thermosetting or thermoplastic resin using a mold equipped with pins for forming projections and holes corresponding to the circuit pattern. b) selectively applying activation treatment for electroless plating only to the inner wall surfaces of the recesses and holes, and c) plating only to the inner wall surfaces of the recesses and holes. A method for manufacturing a printed wiring board, comprising a step of depositing a conductor. (4) A) A step of molding a base body having concave parts corresponding to the circuit pattern from a thermosetting or thermoplastic resin using a mold having convex parts corresponding to the circuit pattern; c) selectively applying activation treatment for electroless plating only to the inner wall surfaces of the recesses and holes, and d) electroless plating to form holes in the recesses and on the inner wall surfaces of the holes. 1. A method for manufacturing a printed wiring board, comprising a step of depositing a conductor only on the surface of the printed wiring board. (5) A) A step of molding a base body having a concave portion corresponding to the circuit pattern from a thermosetting or thermoplastic resin using a mold having a convex portion corresponding to the circuit pattern, and b) Inside the concave portion. and (c) depositing a conductor only in the recesses by electroless plating. Manufacturing method.