JPH0770834B2 - Printed circuit board with exposed inner layer pattern part, and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is directed to a printed circuit board in which a part of an inner layer pattern is exposed from a cavity portion (here, the printed circuit board is not limited to a printed circuit board in a narrow sense, FPC (Flexible Print Circiut
s) and TAB (Tape Automated Bonding) sheets and films are included], and in particular, a printed circuit board with a structure that can improve the wiring density and thermal diffusivity, and the printed circuit board from an etching solution. It relates to a method of manufacturing while completely protecting.

[Conventional technology]

In a conventional printed circuit board with an exposed inner layer pattern part, a part of the inner layer pattern part (for example, die pad part) is exposed from a cavity part for mounting a semiconductor chip later, and a semiconductor chip is mounted there after. And
In addition, a conductive outer layer through hole is formed between the outer layer pattern portions on the front and back surfaces (see, for example, JP-A-61-34989).

Then, the method for manufacturing the printed circuit board is generally such that a copper foil is adhered or copper-plated on both surfaces, and a base material formed so that a part of the inner layer pattern portion is exposed from the cavity portion is used for the outer layer through hole. After performing the primary drilling process, outer layer through-hole copper plating is performed, then an etching resist is applied, and the outer layer pattern portion is formed by etching.

By the way, in the manufacturing process of the printed circuit board, when forming the outer layer pattern portion by etching, the inner layer pattern portion exposed from the cavity portion must not be eroded, and when performing outer layer through-hole copper plating, the inner layer pattern portion also exposed from the cavity portion. The part must not be eroded.

Therefore, for example, it is conceivable to perform the tenting of the entire cavity portion in the same manner as the through hole is tented with the etching resist in the cavity portion where the inner layer pattern portion is exposed. However, the cavity portion is larger than the through hole, and it is difficult in terms of tenting space.
In addition, the inner layer pattern part is plated in advance to withstand etching of gold, solder, etc., and chemical copper
It is also conceivable to perform copper plating to form the outer layer pattern by etching. However, this is also impossible in terms of contamination of the gold-plated portion with metal ions or the like, complication of the solder peeling process, and contamination of the plating liquid itself.

Therefore, the applicant of the present invention has previously formed a copper layer such that the inner layer pattern portion is thicker than the copper thickness of the outer layer portion at the time of applying the etching resist at the latest at the time of manufacturing the printed circuit board, and the copper thickness at the time of etching. A method has been developed in which the inner layer pattern is left by the difference (see Japanese Patent Publication No. 2-9471). As a result, the exposed inner layer pattern portion can be protected.

[Problems to be Solved by the Invention]

By the way, in the conventional printed circuit board in which the inner layer pattern portion is exposed, as the semiconductor elements are becoming higher in density, the printed circuit board is required to be further improved in wiring density. Further, it is desired to further diffuse heat with respect to the heat generation that increases with it.

However, in this type of conventional printed circuit board, as a means to dissipate the heat generated in the semiconductor chip mounted on the surface of the board, an outer layer through hole for heat dissipation is formed separately from the conduction outer layer through hole from the front surface to the back surface. There was nothing else (see, for example, JP-A-61-58297). In other words, none of the semiconductor chips mounted in the cavity has any heat dissipation means, and only the conductive outer layer through holes are provided as the through holes (for example, the above-mentioned JP-A-61-3498).
No. 9).

The present invention relates to a printed circuit board having an exposed inner layer pattern portion, and is intended to solve the above-mentioned problems of the prior art. A first object of the present invention is to have a simple structure and be easy to manufacture, and to further improve the wiring density in accordance with the higher density of semiconductor elements, and to further diffuse the heat generated thereby. It is to provide a printed circuit board in which the inner layer pattern portion is exposed.

The second purpose is that the exposed inner layer pattern portion or inner layer through hole is not corroded by the through hole plating solution or the etching solution at the time of manufacturing the printed circuit board, so that the insulation failure between the inner layer pattern section and the outer layer pattern section around the cavity section is not achieved. It is an object of the present invention to provide a method for manufacturing a printed circuit board in which an inner layer pattern portion is exposed so that the yield and productivity can be improved.

Configuration of the Invention [Means for Solving the Problems] I The printed board according to the present invention in which the inner layer pattern portion is exposed is shown in FIGS. 1 to 6, and the cavity portion (4) to the inner layer pattern portion ( In the printed circuit board where part of 5) is exposed, each outer layer pattern part on the front and back
A conductive outer layer through hole (3) is formed between (2) and a plurality of conductive inner layer through holes (6) are formed from the cavity portion (4) to the outer layer pattern portion (2) on the back surface. .

II The first method of manufacturing a printed circuit board in which the inner layer pattern portion is exposed according to the present invention is to manufacture the printed circuit board shown in FIG. 1, and the process is as shown in FIGS. 7a to 7g. . That is, a printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, (Four)
A method for manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between a back surface and an outer layer pattern section (2), wherein a cavity section (4) exposing the inner layer pattern section (5) and the cavity section After forming a laminated base material (1) having an inner layer through hole (6) from the (4) to the back surface and performing inner layer through hole copper plating (9) on the inner layer through hole (6), at the latest, the substrate (1 ) Before forming the outer layer through-hole (3) between the front and back surfaces and performing the outer layer through-hole copper plating (8), the outer layer through-hole plating solution is used so as to fill the inside of the cavity (4) and the inner layer through-hole (6). Resin that can withstand etching liquid
(11) is filled, then, the outer layer through-hole copper plating (8) is applied over the entire surface, the etching resist film (12) is formed on both front and back surfaces, and the outer layer pattern portion (2) is formed by etching, and finally. , The filled resin (11) and the etching resist film
(12) is removed.

III The second method of manufacturing a printed circuit board in which the inner layer pattern portion is exposed according to the present invention is to manufacture the printed circuit board shown in FIG. 2, and the process is as shown in FIGS. 8a to 8h. . That is, a printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, (Four)
A method for manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between a back surface and an outer layer pattern section (2), wherein a cavity section (4) exposing the inner layer pattern section (5) and the cavity section After forming a laminated base material (1) having an inner layer through hole (6) from the (4) to the back surface and performing inner layer through hole copper plating (9) on the inner layer through hole (6), at the latest, the substrate (1 ) Before forming the outer layer through hole (3) between the front and back surfaces and applying the outer layer through hole copper plating (8), the covering sheet (10) for closing the inner layer through hole (6) on the back surface is provided on the back surface of the cavity (4). While sticking, a resin (11) that can withstand the outer layer through-hole plating solution and the etching solution is filled so as to fill the inside of the cavity part (4), and then the covering sheet on the back surface of the cavity part (4) ( With the 10) removed, the outer layer through-hole copper plating is applied over the entire surface.
(8) is applied, and an etching resist film (12) is formed on both front and back surfaces to form an outer layer pattern portion (2) by etching, and finally, the filled resin (11) and the etching resist film are formed.
(12) is removed.

IV The third method of manufacturing a printed circuit board in which the inner layer pattern portion is exposed according to the present invention is to manufacture the printed circuit board shown in FIG. 3, and the process is as shown in FIGS. 9a to 9h. . That is, a printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, (Four)
A method for manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between a back surface and an outer layer pattern section (2), wherein a cavity section (4) exposing the inner layer pattern section (5) and the cavity section After forming a laminated base material (1) having an inner layer through hole (6) from the (4) to the back surface and performing inner layer through hole copper plating (9) on the inner layer through hole (6), at the latest, the substrate (1 ) Before forming the outer layer through-hole (3) between the front and back surfaces and applying the outer layer through-hole copper plating (8), the covering sheet (10) that closes the inner layer through-hole (6) on the surface is provided on the surface of the cavity (4). While sticking, a resin (11) that can withstand the outer layer through-hole plating solution and the etching solution is filled so as to fill the inside of the cavity (4), and then the outer layer through-hole copper plating (8) is applied over the entire surface. , Forming an etching resist film (12) on both the front and back sides, and etching to form an outer layer pattern. Part forming a (2), finally, is obtained so as to remove the cover sheet (10) and the resin (11) was the filling.

V The fourth method of manufacturing a printed board in which the inner layer pattern portion is exposed according to the present invention is to manufacture the printed board shown in FIG. 4, and the steps are as shown in FIGS. 10a to 10g. . That is, a printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, (Four)
A method for manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between a back surface and an outer layer pattern section (2), wherein a cavity section (4) exposing the inner layer pattern section (5) and the cavity section After forming a laminated base material (1) having an inner layer through hole (6) from the (4) to the back surface and performing inner layer through hole copper plating (9) on the inner layer through hole (6), at the latest, the substrate (1 ) Before forming the outer layer through-hole (3) between the front and back surfaces and applying the primary outer layer through-hole copper plating (13), the outer layer through-hole plating solution is used to fill the cavity (4) and the inner layer through-hole (6). Resin that can withstand etching liquid
(11) is filled, and then the entire surface is plated with primary outer layer through-hole copper (13)
And form a reverse pattern of the outer layer pattern portion with the plating resist (15), and perform secondary outer layer through-hole metal plating (14) with a metal that can withstand the etching liquid, and then remove the plating resist (15). Then, the outer layer pattern portion (2) is formed by etching, and finally, the filled resin (11) is removed.

VI The fifth method of manufacturing a printed circuit board having an exposed inner layer pattern portion according to the present invention is to manufacture the printed circuit board shown in FIG. 5, and the process is as shown in FIGS. 11a to 11h. . That is, a printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, (Four)
A method for manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between a back surface and an outer layer pattern section (2), wherein a cavity section (4) exposing the inner layer pattern section (5) and the cavity section After forming a laminated base material (1) having an inner layer through hole (6) from the (4) to the back surface and performing inner layer through hole copper plating (9) on the inner layer through hole (6), at the latest, the substrate (1 ) Before forming the outer layer through hole (3) between the front and back surfaces and performing the primary outer layer through hole copper plating (13), the covering sheet (10) for closing the inner layer through hole (6) with the back surface is provided with the cavity portion (4). Affixed to the back side of the cavity
(4) A resin (11) that can withstand the outer layer through-hole plating solution and the etching solution is filled so as to fill the inside, and then the coating sheet (10) on the back surface of the cavity section (4) is removed. , The primary through layer copper plating (13) is applied over the entire surface, the plating resist (15) is used to form the reverse pattern of the external pattern part, and the secondary through layer metal plating (14) is applied with a metal that can withstand the etching liquid. Then, the plating resist (15) is removed, the outer layer pattern portion (2) is formed by etching, and finally, the filled resin (11) is removed.

VII The sixth method of manufacturing a printed board in which the inner layer pattern portion is exposed according to the present invention is to manufacture the printed board shown in FIG. 6, and the process is as shown in FIGS. 12a to 12h. . That is, a printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, (Four)
A method for manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between a back surface and an outer layer pattern section (2), wherein a cavity section (4) exposing the inner layer pattern section (5) and the cavity section After forming a laminated base material (1) having an inner layer through hole (6) from the (4) to the back surface and performing inner layer through hole copper plating (9) on the inner layer through hole (6), at the latest, the substrate (1 ) Before forming the outer layer through hole (3) between the front and back surfaces and applying the primary outer layer through hole copper plating (13), the covering sheet (10) for covering the inner layer through hole (6) with the surface is provided on the surface of the cavity (4). Affixed to the cavity part (4)
To fill the inside, a resin (11) that can withstand the outer layer through-hole plating solution and etching solution is filled, and then the primary outer-layer through-hole copper plating (13) is applied over the entire surface.
And form a reverse pattern of the outer layer pattern portion with the plating resist (15), and perform secondary outer layer through-hole metal plating (14) with a metal that can withstand the etching liquid, and then remove the plating resist (15). Then, the outer layer pattern portion (2) is formed by etching, and finally, the filled resin (11) and the covering sheet (10) are removed.

[Action]

A) First, the printed circuit board in which the inner layer pattern portion according to the present invention is exposed is slightly different in structure from any of the first to sixth manufacturing methods described above.
Outer layer through-holes (3) that connect between the outer layer pattern parts (2) on the front and back of the board, and inner layer pattern parts of the cavity part (4)
(5) and a plurality of inner layer through holes (6) for conducting between the outer layer pattern portion (2) on the back surface are formed.

Since the substrate thus has the conduction outer layer through hole (3) and the conduction inner layer through hole (6) from the cavity portion (4), an action which is not present in the conventional one is generated.

That is, in any of the above printed circuit boards, the cavity portion (4)
A semiconductor chip (not shown) will be mounted later on the inner layer pattern part (5) that is partially exposed inside, but an inner layer through hole (6) is provided from the cavity part (4) to the back surface of the substrate. is there. A conventional substrate having heat dissipation through holes has a semiconductor chip mounted on the outer layer pattern portion on the front surface, and the outer layer through holes are provided on the back surface of the substrate for heat dissipation (see, for example, Japanese Utility Model Publication No. 61-58297). Different from Therefore, in the printed circuit board according to the present invention, the board thickness of the board is thinned by the depth of the cavity portion (4), and the inner layer through hole (6) is shortened by the thinner board thickness. Therefore, the heat generated from the semiconductor chip mounted in the cavity (4) is quickly conducted to the back surface of the substrate due to the thin plate thickness and the short through hole (6), and the heat dissipation is greatly improved. .

Further, by providing the conduction inner layer through hole (6), the degree of freedom is increased between the inner layer pattern portions (5) in the cavity portion (4), and the wiring density can be improved. . In particular, it is remarkable when a plurality of semiconductor chips are mounted in the cavity (4), and the conventional one does not have an inner layer through hole in the cavity but only an outer layer through hole (for example, Japanese Patent Laid-Open No. 61-212097). Although it is impossible to route the wiring circuit, the inner layer through hole (6) makes it possible to form a complicated circuit.

The conduction inner layer through hole (6) provided in the cavity (4) is
As a matter of course, since it is shorter than the conductive outer layer through hole, the wiring length through the through hole is short. Compared to the conventional method of mounting a semiconductor chip on the front surface of a substrate and transmitting electrical signals to the back surface through conductive outer layer through holes, the cavity
(4) The transmission speed from the semiconductor chip mounted inside will be significantly increased.

In addition, since the inner layer through hole (6) is formed in a portion where the plate thickness of the cavity portion (4) is thin, the drill diameter can be made smaller than when drilling a conventional outer layer through hole when drilling with a drill, The aspect ratio becomes smaller. As a result, the plating accuracy is improved along with the processing accuracy, the reliability of the through hole is improved, and a small-diameter inner layer through hole can be formed, so that the wiring space can be expanded.

(B) Next, in the production of the printed circuit board in which the inner layer pattern portion according to the present invention is exposed, in any of the above cases, the outer layer through hole is punched to form the outer layer through hole copper plating (8) or the primary outer layer through hole copper plating (8). Before applying 13), fill the resin (11) capable of withstanding the through hole copper plating solution and the etching solution so as to cover the inner layer pattern section (5) and the inner layer through hole (6) in the cavity section (4). There is.

From this filled resin (11), through-hole copper plating on the outer layer
(8) Or primary outer layer through-hole copper plating (13) or secondary outer layer through-hole metal plating (14)
(4) Plating does not adhere to the inner side surface, and the inner layer pattern portion (5) and the outer layer pattern portion (2) around the cavity portion (4) do not cause insulation failure.

Further, even when the outer layer pattern part (2) is etched, the inner layer pattern part (5) and the inner layer through hole (6) in the cavity part (4) are protected from the etching liquid by the filled resin (11). Not damaged.

Furthermore, in the case of filling the resin (11) with the covering sheet (10) attached in advance on the front surface or the back surface of the cavity portion (4), the resin (11) filled in the cavity portion (4) is It will not flow out to the back surface through the inner layer through hole (6). Therefore, the resin (11) having a low viscosity can be used, and the resin (11) can be easily and quickly filled into the cavity (4).

〔Example〕

The printed circuit boards according to the present invention are slightly different from each other in structure as shown in FIG. 1 to FIG. 6, which is different from the first to sixth manufacturing methods according to the present invention. It depends on the process being a little different.

However, in both cases, the outer layer through hole (3) that conducts between the outer layer pattern parts (2) on the front and back of the board and the cavity part
It has an inner layer pattern portion (5) of (4) and a plurality of inner layer through holes (6) electrically connecting between the outer layer pattern portion (2) on the back surface.

The laminated base material (1) may have any number of layers, and the inner layer pattern portion of the intermediate layer
(5) may be exposed from the cavity (4). The surface of the laminated base material (1) is attached with a copper foil (7), but the back surface is only the copper foil (7) as shown in the figure, only the outer layer through-hole copper plating (9), or the copper foil ( There is a product such as 7) with outer layer through-hole copper plating (9).

In the case of attaching the covering sheet (10), the attaching may be performed before or after the outer layer through hole (3) is formed. The metal of the secondary outer layer through-hole metal plating (14) is a metal that can withstand an etching solution such as an alkaline etchant, and gold or solder is used.

Any of the above printed boards, the inner layer through-holes (6) from the cavity (4), it is possible to further improve the wiring density corresponding to the higher density of the semiconductor element, the heat generated accompanying it, As described above, it has a function of being transferred to the back surface of the substrate through the inner layer through hole (6) having a thin plate thickness and a short length so that heat diffusion is achieved.

ii Next, the first manufacturing method according to the present invention, that is, the 7a
The manufacturing method having the steps shown in FIGS. 7 to 7g is for manufacturing the printed circuit board shown in FIG. Here, the resin (11) is filled without using the covering sheet (10).

iii The second and third manufacturing methods according to the present invention, that is, the manufacturing methods including the steps shown in FIGS. 8a to 8h and 9a to 9h, are shown in FIGS. The printed circuit board shown in is manufactured.

Here, unlike the first manufacturing method described above, resin (11) is used to fill the coating sheet (10) in both cases, and in FIG. 8b, the coating sheet (10) is placed on the back surface of the cavity (4). The coating sheet (10) is attached to the cavity in Fig. 9b.
(4) Affixed to the surface.

ix The fourth manufacturing method according to the present invention, that is, the manufacturing method having the steps shown in FIGS. 10a to 10g, is for manufacturing the printed circuit board shown in FIG.

Here, the cavity part (4) is used without using the covering sheet (10).
Resin (11) into the primary outer layer through-hole copper plating (1
After performing 3), a reverse pattern of the outer layer pattern portion is formed by the plating resist (15), and then the secondary outer layer through-hole metal plating (14) is performed.

The metal of the secondary outer layer through-hole metal plating (14) is a metal that can withstand an etching liquid such as an alkaline etchant as described above, and gold or solder may be used.

v The fifth and sixth manufacturing methods according to the present invention, that is, the manufacturing methods including the steps shown in FIGS. 11a to 11h, and 12a to 12h are shown in FIGS. The printed circuit board shown is to be manufactured.

Here, unlike the above-mentioned fourth embodiment, the covering sheet (10) is used in all cases, and in FIG. 11b, the covering sheet (10) is used.
Is attached to the back surface of the cavity portion (4), and in FIG. 12b, the covering sheet (10) is attached to the front surface of the cavity portion (4).

In each of the above manufacturing methods, the resin (11) to be filled in the cavity (4) is a silicon-based resin as a resin that can withstand a through-hole plating solution and an etching solution such as ferric chloride or an alkaline etchant. You can use it.

When the covering sheet (10) is used, the covering sheet (1
For removal of (0), when it is attached to the back surface of the cavity (4), before applying the outer layer through-hole copper plating (8) and primary outer layer through-hole copper plating (13), it is attached to the surface of the cavity (4). May be performed simultaneously with the removal of the resin (11).

EFFECTS OF THE INVENTION a) As is clear from the above, the printed circuit board according to the present invention in which the inner layer pattern portion is exposed has an outer layer through hole that conducts between the outer layer pattern portions on the front and back surfaces of the substrate and an inner layer pattern portion of the cavity portion. A plurality of inner layer through holes are formed to electrically connect between the outer layer pattern portions on the back surface.

Therefore, the printed circuit board according to the present invention has the following effects, unlike the conventional printed circuit board having only outer layer through holes.

That is, due to the inner layer through holes, the heat generated in the semiconductor chip mounted in the cavity is quickly transferred to the back surface of the substrate due to the thin plate thickness and the short inner layer through holes, and the heat dissipation can be greatly improved.

Further, the inner layer through holes increase the degree of freedom between the inner layer pattern portions in the cavity portion, and can improve the wiring density. In particular, a complicated circuit can be formed when a plurality of semiconductor chips are mounted in the cavity.

Similarly, due to the conductive inner layer through hole, the wiring length from the semiconductor chip in the cavity portion through the through hole is shortened, and the transmission speed of the electric signal can be significantly increased.

Furthermore, the inner layer through hole formed from the cavity is
Since the board thickness of that part is thin, the aspect ratio when drilling is small, the plating accuracy is improved along with the processing accuracy, the reliability as a through hole is increased, and a small through hole can be formed. It is also possible to improve the wiring space.

B) According to the method for manufacturing a printed circuit board of the present invention, the inside of the cavity formed in the substrate is filled with a resin capable of withstanding the through hole plating solution and the etching solution before the outer layer through hole plating is performed at the latest. There is.

Therefore, this resin filled in the cavity can prevent copper plating, gold plating or solder plating from adhering to the inner surface of the cavity during outer layer through-hole plating, resulting in poor insulation between the inner layer pattern and the outer layer pattern around the cavity. Can be prevented. At the same time, it is possible to prevent the inner layer pattern portion and the inner layer through holes from being eroded by the etching liquid.

Therefore, at the time of manufacturing the above-mentioned printed circuit board, the exposed inner layer pattern and inner layer through holes are prevented from being corroded by the through hole plating solution or the etching solution to prevent insulation failure between the inner layer pattern section and the outer layer pattern section around the cavity section. Therefore, the yield and productivity can be improved.

Further, in the case where the front surface or the back surface of the cavity portion is filled with the resin in the state where the covering sheet is attached in advance, the resin filled in the cavity portion can be prevented from flowing out to the back surface through the inner layer through hole, and the viscosity is low. Since resin can be used, filling of the resin into the cavity can be performed easily and quickly.

[Brief description of drawings]

FIG. 1 is a partially enlarged vertical sectional view of a printed circuit board formed by the first manufacturing method of the present invention, and FIG. 2 is a partially enlarged vertical sectional view of a printed circuit board formed by the second manufacturing method of the present invention. FIG. 3 is a partially enlarged vertical sectional view of a printed circuit board formed by the third manufacturing method of the present invention, and FIG. 4 is a partially enlarged vertical sectional view of a printed circuit board formed by the fourth manufacturing method of the present invention. FIG. 5 is a partially enlarged vertical sectional view of a printed circuit board formed by the fifth manufacturing method of the present invention, and FIG. 6 is a partially enlarged vertical sectional view of a printed circuit board formed by the sixth manufacturing method of the present invention. 7a to 7g are partially enlarged vertical sectional views of respective steps in the first manufacturing method for forming the printed circuit board shown in FIG. 1, and FIGS. 8a to 8h are printed circuit boards shown in FIG. FIG. 9a to FIG. 9h are partially enlarged vertical cross-sectional views of respective steps in the second manufacturing method for forming the printed board shown in FIG. FIG. 10a to FIG. 10g are partial enlarged vertical cross-sectional views of respective steps in the third manufacturing method for forming a printed circuit board, and FIGS. FIGS. 11a to 11h are enlarged vertical sectional views showing a part of each step in the fifth manufacturing method for forming the printed circuit board shown in FIG. 5, and FIGS. 12a to 12h are sixth sectional views. It is a partial expanded longitudinal cross-sectional view of each process in the 6th manufacturing method which forms the printed circuit board shown in a figure. Drawing symbol (1) -Substrate, (11) -Resin (2) -Outer layer pattern part, (12) -Etching resist film (3) -Outer layer through hole, (13) -Primary outer layer through hole copper plating (4) -Cavity Part, (14) -secondary outer layer through-hole metal plating (5) -inner layer pattern part, (15) -plating resist (6) -inner layer through-hole (7) -copper foil, (8) -outer layer through-hole copper plating, (9) ) -Inner layer through-hole copper plating, (10) -Coating sheet

Claims (7)

[Claims] 1. In a printed circuit board in which a part of the inner layer pattern portion (5) is exposed from the cavity portion (4), a conduction outer layer through hole (3) is formed between each outer layer pattern portion (2) on the front and back surfaces. A printed board having an exposed inner layer pattern portion, wherein a plurality of conductive inner layer through holes (6) are formed from the cavity portion (4) to the outer layer pattern portion (2) on the back surface. 2. A printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), and has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, A method of manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between the cavity part (4) and the outer layer pattern part (2) on the back surface, wherein the inner layer pattern part (5) is exposed. ), And a laminated base material (1) having an inner layer through hole (6) from the cavity part (4) to the back surface is formed, and after inner layer through hole copper plating (9) is applied to the inner layer through hole (6), At the latest, before the outer layer through hole (3) is bored between the front and back surfaces of the base material (1) and the outer layer through hole copper plating (8) is performed, the inside of the cavity portion (4) and the inner layer through hole (6) are filled, Resin that can withstand outer layer through-hole plating solution and etching solution
(11) is filled, then, the outer layer through-hole copper plating (8) is applied over the entire surface, the etching resist film (12) is formed on both front and back surfaces, and the outer layer pattern portion (2) is formed by etching, and finally. , The filled resin (11) and the etching resist film
(12) is removed, a method for manufacturing a printed circuit board having an exposed inner layer pattern portion. 3. A printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), and has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, A method of manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between the cavity part (4) and the outer layer pattern part (2) on the back surface, wherein the inner layer pattern part (5) is exposed. ), And a laminated base material (1) having an inner layer through hole (6) from the cavity part (4) to the back surface is formed, and after inner layer through hole copper plating (9) is applied to the inner layer through hole (6), At the latest, before forming the outer layer through-holes (3) between the front and back surfaces of the base material (1) and performing the outer layer through-hole copper plating (8), the coating sheet (10) that closes the inner layer through-holes (6) on the back surface is cavity While sticking on the back surface of the part (4) and filling the cavity part (4), the outer layer through-hole plating solution and etchant Withstand use liquid advance filled with a resin (11), then, the cavity (4) in a state of removing the rear surface of the cover sheet (10), an outer layer through hole copper plating over the entire surface
(8) is applied, and an etching resist film (12) is formed on both front and back surfaces to form an outer layer pattern portion (2) by etching, and finally, the filled resin (11) and the etching resist film are formed.
(12) is removed, a method for manufacturing a printed circuit board having an exposed inner layer pattern portion. 4. A printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), and has conductive outer layer through holes (3) between the outer layer pattern parts (2) on the front and back surfaces, A method of manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between the cavity part (4) and the outer layer pattern part (2) on the back surface, wherein the inner layer pattern part (5) is exposed. ), And a laminated base material (1) having an inner layer through hole (6) from the cavity part (4) to the back surface is formed, and after inner layer through hole copper plating (9) is applied to the inner layer through hole (6), At the latest, before forming the outer layer through hole (3) between the front and back surfaces of the base material (1) and performing the outer layer through hole copper plating (8), the covering sheet (10) that closes the inner layer through hole (6) on the surface is cavity. While sticking to the surface of the part (4) and filling the cavity part (4) with the outer layer through-hole plating solution and etchant A resin (11) that can withstand a working solution is filled in, and then an outer layer through-hole copper plating (8) is applied over the entire surface, etching resist films (12) are formed on both front and back surfaces, and the outer layer pattern part (2) is etched. And finally, removing the filled resin (11) and the covering sheet (10), the method for producing a printed circuit board in which an inner layer pattern portion is exposed. 5. A printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), and has a conductive outer layer through hole (3) between the outer layer pattern parts (2) on the front and back surfaces, A method of manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between the cavity part (4) and the outer layer pattern part (2) on the back surface, wherein the inner layer pattern part (5) is exposed. ), And a laminated base material (1) having an inner layer through hole (6) from the cavity part (4) to the back surface is formed, and after inner layer through hole copper plating (9) is applied to the inner layer through hole (6), At the latest, before filling the outer layer through hole (3) between the front and back surfaces of the base material (1) and performing the primary outer layer through hole copper plating (13), so as to fill the inside of the cavity part (4) and the inner layer through hole (6), Resin that can withstand outer layer through-hole plating solution and etching solution
(11) is filled, and then the entire surface is plated with primary outer layer through-hole copper (13)
And form a reverse pattern of the outer layer pattern portion with the plating resist (15), and perform secondary outer layer through-hole metal plating (14) with a metal that can withstand the etching liquid, and then remove the plating resist (15). Then, the outer layer pattern portion (2) is formed by etching, and finally, the filled resin (11) is removed, which is a method for manufacturing a printed circuit board in which the inner layer pattern portion is exposed. 6. A printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), and has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, A method of manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between the cavity part (4) and the outer layer pattern part (2) on the back surface, wherein the inner layer pattern part (5) is exposed. ), And a laminated base material (1) having an inner layer through hole (6) from the cavity part (4) to the back surface is formed, and after inner layer through hole copper plating (9) is applied to the inner layer through hole (6), At the latest, before forming the outer layer through hole (3) between the front and back surfaces of the base material (1) and applying the primary outer layer through hole copper plating (13), a covering sheet (10) for closing the inner layer through hole (6) on the back surface is provided. Affixed to the back of the cavity (4), and the cavity (4)
A resin (11) that can withstand the outer layer through-hole plating solution and etching solution is filled so as to fill the inside, and then the covering sheet (10) on the back surface of the cavity section (4) is removed, and the entire surface is covered. Apply the primary outer layer through-hole copper plating (13), form the reverse pattern of the outer layer pattern part with the plating resist (15), and perform the secondary outer-layer through-hole metal plating (14) with a metal that can withstand the etching liquid, and then, The plating resist (15) is removed, the outer layer pattern portion (2) is formed by etching, and finally, the filled resin (11) is removed, and the inner layer pattern portion is exposed. Printed circuit board manufacturing method. 7. A printed circuit board in which a part of the inner layer pattern part (5) is exposed from the cavity part (4), and has a conductive outer layer through hole (3) between each outer layer pattern part (2) on the front and back surfaces, A method of manufacturing a printed circuit board having a plurality of conductive inner layer through holes (6) between the cavity part (4) and the outer layer pattern part (2) on the back surface, wherein the inner layer pattern part (5) is exposed. ), And a laminated base material (1) having an inner layer through hole (6) from the cavity part (4) to the back surface is formed, and after inner layer through hole copper plating (9) is applied to the inner layer through hole (6), At the latest, before forming the outer layer through hole (3) between the front and back surfaces of the base material (1) and applying the primary outer layer through hole copper plating (13), the covering sheet (10) for closing the inner layer through hole (6) on the surface is provided. Affixed to the surface of the cavity part (4) and the cavity part (4)
A resin (11) that can withstand the outer layer through-hole plating solution and the etching solution is filled so as to fill the inside, and then the primary outer-layer through-hole copper plating (13) is applied over the entire surface.
And form a reverse pattern of the outer layer pattern portion with the plating resist (15), and perform secondary outer layer through-hole metal plating (14) with a metal that can withstand the etching liquid, and then remove the plating resist (15). Then, the outer layer pattern portion (2) is formed by etching, and finally, the filled resin (11) and the covering sheet (10) are characterized in that the inner layer pattern portion is exposed. Printed circuit board manufacturing method.