JPH07326838A - Printed wiring board and its manufacture - Google Patents

Abstract

PURPOSE:To provide a printed wiring board having an insulating board provided with a through hole of high reliability which obliquely and surely connects the respective conducting patterns on the surface and the back of the insulating board, and a manufacturing method of it. CONSTITUTION:The printed wiring board is provided with a through hole 8 constituted of a blind hole 3 formed in the board thickness direction on one surface, another hole 2 opened at the other surface extends obliquely and is communicating with the hole 3, and a copper-plating layer 7 stuck on the wall surfaces of the hole 2 and the hole 3. A conductor pattern A4 and a conductor pattern C6 of the surface and the back are connected by using the through hole 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board and a method for manufacturing the same, and more particularly to a printed wiring board having through holes and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, in the case of electrically connecting conductor patterns at different positions on different layers of a printed wiring board, diagonally forming through holes in an insulating substrate for connection. For example, in Japanese Unexamined Patent Publication No. 2-60188, as shown in FIG. 5, a conductor pattern A4, a slanted through hole 10, and a conductor pattern B which are formed on a predetermined position of the insulating substrate 1 by a chemical treatment.
5, conductor pattern C6 is provided. The conductor pattern A4 is connected to the conductor pattern C6 on the other surface of the insulating substrate 1 by the oblique through hole 10. On the other hand, the conductor pattern A4 and the conductor pattern C6 are composed of a land portion around the opening of the oblique through hole 10 and a circuit portion connected thereto.

In this conventional method of manufacturing a printed wiring board, first, a counterbore having a depth of about 0.1 to 0.2 mm is inserted as a guide hole in the lower surface of the copper foil-clad insulating substrate 1 and a drill is used. The upper surface of the insulating substrate 1 is obliquely penetrated to form an oblique through hole. Next, an activation treatment is applied to the surface of the copper foil and the wall surface of the diagonal through hole, and copper is deposited by electroless plating to form a diagonal through hole 10. The upper and lower copper foils are electrically connected through the diagonal through hole 10. To take. Next, a predetermined conductor pattern including the oblique through hole 10, the conductor pattern A4, and the conductor pattern C6 is formed through a photosensitive photoresist processing step and a copper foil etching processing step.

In another conventional example, Japanese Patent Laid-Open No. 4-293
As disclosed in Japanese Unexamined Patent Publication No. 98-989, a main through hole that penetrates a surface layer of a multilayer printed wiring board in a direction perpendicular to the surface of the board, and an oblique branch from a predetermined inner layer position of the main through hole. It has a trunk via hole connected to a predetermined other layer.

[0005]

As described above, in the conventional printed wiring board provided with the oblique through holes, the terminal positions of the oblique through holes with respect to the surface of the insulating substrate are displaced from the predetermined positions. In such a case, there is a problem in that a land such as a drill exit side is out of place.

On the other hand, in the case of a multi-layer printed wiring board having a main through hole and a trunk via hole, a problem arises that a trunk via hole that is obliquely branched causes a defect such as a poor seating due to a deviation of the tilt angle. there were.

An object of the present invention is to provide a highly reliable printed wiring having through holes for surely connecting conductor patterns on both front and back surfaces without causing problems such as poor seating due to displacement of terminal positions of oblique through holes. It is to provide a plate and a manufacturing method thereof.

[0008]

A printed wiring board according to a first aspect of the present invention has a non-penetrating semi-through hole provided in the plate thickness direction on one surface and the semi-penetrating hole provided on the other surface. And a non-penetrating diagonal semi-through hole that is diagonally crossed and connected, and a through hole formed by the diagonal semi-through hole and a copper plating layer adhered to the wall surface of the semi-through hole, and the through hole And an insulating substrate having conductor patterns formed on both surfaces to be connected.

The method of manufacturing a printed wiring board according to the second aspect of the present invention comprises a step of forming a non-through hole in the thickness direction of one side of an insulating substrate to form a semi-through hole, and another surface from this side. A step of forming a diagonal semi-through hole by diagonally punching a non-through hole that intersects and connects with the wall surface of the semi-through hole, both surfaces of the insulating substrate, the half-through hole, and the diagonal half-through hole. A step of forming a conductor layer and a through hole by applying copper plating to the wall surface and depositing a copper plating layer, and a step of forming a conductor pattern connected to the through hole on both surfaces of the insulating substrate by photo printing and etching. including.

The method for manufacturing a printed wiring board according to the third aspect of the present invention comprises a step of forming a non-through hole on one surface of an insulating substrate obliquely with respect to this surface, and forming an oblique semi-through hole, and the other step. Detecting the end of the oblique half through hole from the surface and forming a half through hole by punching a non-through hole in the plate thickness direction so as to connect at the position of this end, both sides of the insulating substrate and the oblique half A step of forming a conductor layer and a through hole by applying copper plating to the wall surfaces of the through hole and the semi-through hole and forming a conductor layer and a through hole, and connecting the through hole to both surfaces of the insulating substrate by photo printing and etching. And a step of forming a conductor pattern.

[0011]

Embodiments of the present invention will now be described with reference to the drawings.

1 (a) and 1 (b) are a plan view and a sectional view taken along the line AA 'of the printed wiring board according to an embodiment of the present invention. As shown in FIGS. 1A and 1B, the conductor pattern A4 and the conductor pattern B5 are provided at predetermined positions on one surface of the insulating substrate 1, and the other surface deviated from the vertical direction of the conductor pattern A4. A conductor pattern C6 is provided at the position of, and the conductor pattern A4 is a non-penetrating semi-through hole 3 provided in the direction of the thick plate and a non-penetrating diagonal semi-penetrating hole which is connected to the semi-penetrating hole 3 by diagonally intersecting it 2 and a conductor pattern C6 through a through hole 8 formed of a copper plating layer deposited on these wall surfaces. The conductor pattern A4 is composed of a land portion around the diagonal half through hole 2 and a circuit portion connected thereto, and the conductor pattern C6 is composed of a land portion around the half through hole 3 and a circuit portion connected thereto. With this structure, the conductor pattern B5 can be provided at the position on the other surface of the insulating substrate 1 corresponding to the semi-through hole 3, so that the wiring density can be increased.

In this embodiment, an insulating substrate 1 made of a copper foil-clad laminate having a thickness of 1.6 mm is used, and the diameters of the diagonal half-through holes 2 and the half-through holes 3 are each 0.4 mm, and the circumference of each of them is set to 0.4 mm. Insulating substrate 1 with land diameter 0.8mm and diagonal half through hole 2
The inclination angle with respect to the surface was 45 degrees.

Next, a method of manufacturing the printed wiring board having the structure shown in FIGS. 1A and 1B will be described.

2 (a) to 2 (c) are sectional views showing the order of steps for explaining the first embodiment of the method for manufacturing a printed wiring board of the present invention. In the first embodiment of the method for manufacturing a printed wiring board of the present invention, first, as shown in FIG. 2A, an insulating substrate having a thickness of 1.6 mm in which copper foils are previously adhered to both surfaces of an insulating base material. The non-penetrating semi-penetrating hole 3 is formed by drilling a depth of 1.0 mm in the plate thickness direction using a cone having a diameter of 0.4 mm from one surface. Next, as shown in FIG. 2B, the diameter is set so that the semi-through hole 3 is connected at a depth of 0.8 mm at an inclination angle of 45 degrees from the other surface of the insulating substrate 1. The non-penetrating diagonal semi-through hole 2 is formed by drilling with a cone of 0.4 mm. In this case, the maximum tilt angle is +1
Even if it shifts by 8 to -8 degrees, the oblique semi-through hole 2 is connected to the pre-formed semi-through hole 3 without any abnormality. When the inclination angle deviates by +18 degrees from 45 degrees, it is near the surface of the insulating substrate 1, that is, at a depth of 0, and when it deviates by -8 degrees, near the bottom or at a depth of 1.0 mm. Connect with the half through hole 3.

Next, as shown in FIG. 2C, the copper foil surface of the insulating substrate 1 and the wall surfaces of the diagonal semi-through holes 2 and the semi-through holes 3 are subjected to activation treatment, electroless plating and then electroplating. A copper plating layer 7 is deposited to form a conductor layer and a through hole 8,
Conduction is established between the conductor layers on both sides via the through holes 8. Furthermore, application of photosensitive photoresist, patterning,
A conductor pattern A including a predetermined land portion and a circuit portion and electrically connected through the through hole 8 by etching the conductor layer.
4 and the conductor pattern C6 and the semi-through hole 3 to obtain a printed wiring board having an insulating substrate having the conductor pattern B5 formed at the position of the other surface corresponding to the hole.

3 (a) and 3 (b) are plan views showing the order of steps for explaining the second embodiment of the method for manufacturing a printed wiring board of the present invention, and FIGS. 3 (c) and 3 (d) are respectively (a). , (B) corresponding to line BB ', CC' line sectional view, FIG. 4 is a plan view of the printed wiring board obtained by the process of FIG. A second embodiment of the printed wiring board according to the present invention will first be described with reference to FIGS.
As shown in FIG. 3, the diameter of the insulating substrate 1 having a thickness of 1.6 mm, which is obtained by previously adhering copper foils to both surfaces of the insulating base material, is 0.
A diagonal semi-through hole is formed by drilling with a 4 mm cone at a tilt angle of 45 degrees with respect to the surface and a depth of 2.2 mm. At this time, even if the end point position of the diagonal semi-through hole is shifted from the designed position of the diagonal half-through hole 33 in the horizontal direction, the shifted end point position of the diagonal half-through hole 32 is detected using X-rays.

Next, the diameter is 0.4 with the semi-through hole forming position 34, which is the radius of the cone offset from the end position, as the center.
By forming the semi-through hole 3 by drilling using a pyramid of mm, the diagonal semi-through hole 32 and the semi-through hole 3 in the case of misalignment are connected without any abnormality. Further, as described in the first embodiment, the oblique semi-through holes 32 and the semi-through holes 3 are connected without any abnormality when the oblique semi-through holes 32 are misaligned even when the inclination angle of the oblique semi-through holes 32 is misaligned by a maximum of about 20 degrees. To do.

Next, as shown in FIG. 4, similarly to the first embodiment, the conductor layer and the through hole 8 are formed by activation treatment, electroless plating, and electroplating, and then a photosensitive photoresist is applied. By patterning and etching the conductor layer,
A printed wiring board having an insulating substrate having a conductor pattern including a predetermined land portion and a circuit portion and electrically connected through the through hole 8 is obtained. In addition, in this embodiment, the land 9 around the semi-through hole 3 is formed into an elliptical shape, so that even if the position of the semi-through hole 3 moves, the seat breakage can be more reliably prevented.

[0020]

As described above, according to the present invention, a non-penetrating semi-through hole having a through hole provided on one surface and a non-penetrating semi-through hole provided on the other surface are connected so as to obliquely intersect each other. Since the diagonal half-through holes and the copper plating layer deposited on the wall surface are formed, even if the diagonal half-through holes are formed deviated in either the plate thickness direction or the horizontal direction of the insulating substrate. A printed wiring board with a reliable connection between the half-through hole and the diagonal half-through hole, with no problems such as out-of-seats, and a highly reliable through-hole and an insulating substrate with conductor patterns on both front and back surfaces connected to this through-hole can be obtained. There is an effect that is.

[Brief description of drawings]

1A and 1B are a plan view and a sectional view taken along the line AA ′ of the printed wiring board according to an embodiment of the present invention.

2 (a) to 2 (c) are cross-sectional views showing the order of steps for explaining the first embodiment of the method for manufacturing a printed wiring board according to the present invention.

3 (a) and 3 (b) are plan views showing the order of steps for explaining a second embodiment of the method for manufacturing a printed wiring board according to the present invention,
(C) and (d) are B corresponding to (a) and (b), respectively.
FIG. 6 is a cross-sectional view taken along line B-C 'and C-C'.

FIG. 4 is a plan view of a printed wiring board obtained by the process of FIG.

FIG. 5 is a cross-sectional view showing the configuration of an example of a conventional printed wiring board.

[Explanation of symbols]

 1 Insulating substrate 2 Diagonal half-through hole 3 Half-through hole 4 Conductor pattern A 5 Conductor pattern B 6 Conductor pattern C 7 Copper plating layer 8 Through hole 9 Land 10 Oblique through hole 32 Diagonal half through hole in case of misalignment 33 Design Diagonal half through hole 34 Half through hole forming position

Claims (3)

[Claims] 1. A non-penetrating semi-penetrating hole provided on one surface in the plate thickness direction, and a non-penetrating diagonal semi-penetrating hole provided on the other surface and connecting by diagonally intersecting the semi-penetrating hole. An insulating substrate provided with a through hole constituted by the diagonal half through hole and a copper plating layer deposited on the wall surface of the half through hole, and conductor patterns formed on both surfaces connected by the through hole A printed wiring board comprising: 2. A step of forming a non-through hole in one surface of an insulating substrate in the plate thickness direction to form a semi-through hole, and a step of crossing the wall surface of the half-through hole obliquely from the other surface with respect to this surface. And a step of forming a diagonal semi-through hole by punching a non-through hole to be connected,
Copper plating is applied to both sides of the insulating substrate, the wall surface of the half through hole and the wall surface of the diagonal half through hole to form a conductor layer and a through hole by depositing a copper plating layer, and the insulation is performed by a photo printing method and etching. And a step of forming conductor patterns connected to the through holes on both surfaces of the substrate. 3. A step of forming a non-through hole on one surface of an insulating substrate obliquely with respect to this surface to form an oblique semi-through hole,
Detecting the end of the diagonal semi-through hole from the other surface and forming a semi-through hole by punching a non-through hole in the plate thickness direction so as to connect at the position of this end, both surfaces of the insulating substrate and the A step of forming a conductor layer and a through hole by applying copper plating on the diagonal half through hole and the wall surface of the half through hole, and forming a conductor layer and a through hole by the photo printing method and etching; And a step of forming a conductor pattern connected to the printed wiring board.