JPH10308564A - Printed wiring board and its manufacturing method - Google Patents

Abstract

(57) [Summary] [PROBLEMS] When mounting surface mounting components having different mounting forms, it is not necessary to redesign or remanufacture the entire printed wiring board, shortening the design time and preparing jigs and tools. Is unnecessary or simple, and an increase in manufacturing cost is suppressed. SOLUTION: Another surface mounting component pad which is laminated on a partial area including a mounting area of a surface mounting component, one surface of which is connected to a surface mounting component pad group of a printed wiring board and the other surface has a different mounting form. A group is formed, and has an auxiliary laminate in which both pad groups are connected by an inner layer circuit pattern and via holes. This printed wiring board has a) an insulating resin layer laminated on a partial area including a mounting area of a surface mount component, b) a via hole and a circuit pattern formed in the insulating resin layer, c).
By repeating the above steps a and b, the surface mount component pad group of the printed wiring board is connected to another surface mount component pad group formed on the uppermost insulating resin layer surface and having a different mounting form. It can be manufactured by the following.

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 on which surface mounting components having different mounting forms can be mounted, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Surface mount devices (hereinafter, also referred to as SMDs) mounted on a printed wiring board include:
There are many types with different implementations. That is, a semiconductor integrated circuit device having the same function (hereinafter referred to as IC)
However, if the packages are different, the mounting form is different.

For example, a flat package having a gull-wing type pin (lead) provided on two sides of a thick plate-shaped package (DIP) or a flat package having a gull-wing type pin (lead) provided on four sides. (Quad Flat Package, hereinafter referred to as QFP) is widely used. Also, in order to increase the mounting density, a pin grid array (PGA) with many pins (leads) standing on the lower surface of the package
Also, a ball grid array (Ball Grid Array,
BGA) is also used. In order to further increase the mounting density, there is a type using a form such as a CSP (Chip Scale Package).

[0004] In addition to terminals having different shapes, such as pins (leads) or balls, there are also terminals having different terminal intervals. In this way, when the mounting form changes due to changes in the terminal form or terminal spacing, conventionally, the printed wiring boards corresponding to the mounting form are separately designed,
I was making different printed wiring boards.

[0005]

2. Description of the Related Art In order to mount a surface mount component (SMD) having a different mounting form as described above, redesigning and newly manufacturing a printed wiring board requires a long manufacturing time, and requires a long time. Not only is it necessary to prepare tools and the like, but this also leads to a significant increase in manufacturing costs.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is unnecessary to redesign or remanufacture the entire printed wiring board when mounting surface-mounted components having different mounting forms. It is a first object of the present invention to provide a printed wiring board capable of shortening the design time, making the preparation of jigs and tools unnecessary or simple, and suppressing an increase in manufacturing cost. A second object of the present invention is to provide a method for manufacturing the printed wiring board.

[0007]

According to the present invention, a first object of the present invention is to provide a printed wiring board for mounting surface mounted components, wherein the printed wiring board is laminated on a partial area including a mounting area for surface mounted components, and one surface of the printed wiring board is mounted on the printed wiring board. It is characterized by having an auxiliary laminate board connected to the surface mount component pad group of the board and having another surface mount component pad group having a different mounting form formed on the other surface, and connecting both pad groups with an inner layer circuit pattern and via holes. And a printed wiring board.

A second object of the present invention is to provide a method for manufacturing a printed wiring board for mounting surface-mounted components, comprising the steps of: a) laminating an insulating resin layer on a partial area including a mounting area for surface-mounted components; A via hole and a circuit pattern are formed in the insulating resin layer, and c) the steps a and b are repeated to form a surface mount component pad group of the printed wiring board on the uppermost insulating resin layer surface. It is achieved by a method for manufacturing a printed wiring board, wherein the method is connected to a pad group for another different surface mount component.

When the insulating resin layer is laminated here, the insulating resin layer can be uniformly pressed by laminating the release resin through a release sheet in a region other than the insulating resin layer. The resin laminated on the release sheet is released together with the release sheet after forming the auxiliary laminate.

[0010]

FIG. 1 shows a printed wiring board 10 used in the present invention.
FIG. 2 is an exploded perspective view showing an auxiliary laminate according to the present invention, and FIG. 3 is an exploded perspective view showing one process during the production. FIG. 4 is a diagram showing an example of the inner layer circuit pattern, in which the positions of the pads on the printed wiring board and the pads on the auxiliary laminated surface are shifted so as not to overlap. FIG. 5 is an end view taken along line VV in FIG. 4, and FIG. 6 is a developed view showing the connection between the pads 16A and 24A in FIG. 7 is a diagram showing a manufacturing process, FIG. 8 is a diagram showing a photo via hole forming process, and FIG. 9 is a diagram showing a laser via hole forming process.

A printed wiring board 10 shown in FIG.
A first surface-mounted component (SMD) 12 such as a mold IC can be mounted. That is, the first SMD 12 has a DIP type package having a large number of gull-wing type leads 14 on two sides, and the first
A pad 16 is formed at a position corresponding to the lead 14 of the SMD 12. These pads 16 are formed at intervals corresponding to the intervals between the leads 14 and form a group (hereinafter referred to as a first pad group) 18.

According to the present invention, as shown in FIG. 2, an auxiliary laminate 22 is laminated on the partial area 20 including the first pad group 18, and a large number of pads are arranged on the surface of the auxiliary laminate 22 in a grid pattern. 24, a first pad group 18 and a second pad group 26 are formed by the inner layer circuit pattern of the auxiliary laminate 22 and via holes (also referred to as via holes or via holes) as described later. Connected. The second pad group 26 includes the first SMD
12, a second SMD 28 having a different mounting form can be mounted. Here, as the second SMD 28, for example, one having a terminal group having a ball grid array structure can be used.

Next, a method of manufacturing the auxiliary laminate 22 will be described with reference to FIG.
This will be described with reference to FIGS. As shown in the process diagram of FIG. 7, first, a printed wiring board 10 to be a substrate as shown in FIG. 1 is prepared (Step 100 in FIG. 7), and the mounting area 20 of the first SMD 12 (see FIGS. Release sheet 3 in the area of
0 is attached (step 102). Then, the insulating resin sheet 32 cut into the shape of the mounting area 20 is stacked on the mounting area 20,
Insulating resin sheet 3 cut out from this mounting area 20
4 on an area other than the mounting area 20 (step 10).
4). And these are thermocompression-bonded with a press machine (step 106).

As will be described later, via holes 50 are formed in the insulating resin sheet 32 that has been thermocompression-bonded, and circuit patterns (inner circuit patterns) are formed on the surface of the insulating resin sheet 32.
52 are formed (step 108). Lamination of insulating resin sheet (Step 104), thermocompression bonding (Step 10)
6), formation of via holes and circuit patterns (Step 1)
08) is repeated a plurality of times to form the second pad group 26 on the uppermost layer and connect the second pad group 26 to the first pad group 18 (step 11).
0). Thereafter, the release sheet 30 and the insulating resin sheet 34 laminated on the release sheet 30 are combined with the printed wiring board 1.
If it is stripped from 0 (step 112), the product is completed (step 114).

Next, the via hole 50 and the inner layer circuit pattern 5
The method of connecting the first pad group 18 and the second pad group 26 by the method 2 will be described with reference to FIGS. First, a first-layer insulating resin sheet 32A is laminated on the SMD mounting area 20 of the printed wiring board 10, and a via hole 50A and a first-layer inner-layer circuit pattern 52A are formed. The first pad group 18 is connected to the first-layer inner-layer circuit pattern 52 by the via hole 50A.

Similarly, a second-layer insulating resin sheet 32B is laminated, and a via hole 50B and a second-layer inner-layer circuit pattern 5 are formed.
Form 2B. The via hole 50B allows the first-layer inner-layer circuit pattern 52A and the second-layer inner-layer circuit pattern 52 to be formed.
Connection with B is performed. Similarly, the third-layer insulating resin sheet 3
2C are stacked, and the pads 24 of the second pad group 26 formed on the upper surface (uppermost surface) thereof are
It is connected to the inner layer circuit pattern 52B.

As described above, the inner-layer circuit patterns 52A, 52
The corresponding pads 16 and 24 of the pad groups 18 and 26 are connected via B. Here, the insulating resin sheet 32A
Although C is laminated in three layers, the number of layers may be appropriately changed depending on the number of pads and the like.

Next, a method of forming the via hole 50 will be described with reference to FIGS. FIG. 8 shows a method of forming a photo via hole using a photocurable resin. First, a circuit pattern 62 is formed on a substrate 60 (A in FIG. 8), and a photoresist 64 made of a photocurable resin is applied or pasted thereon (B in FIG. 8). A latent image of the via hole is formed in the photoresist 64 by overlaying a photomask 66 having a via hole pattern baked on the photocurable resin 64 and exposing with a UV ray (C in FIG. 8).

After removing and developing the photomask 66, the photoresist 64 in the unexposed portion (pattern portion of the via hole) is removed to form a small hole 68 corresponding to the pattern of the via hole (D in FIG. 8). If this surface is subjected to copper plating (electroless copper plating is performed after electroless copper plating) to form a copper plating layer 70, the circuit pattern 6 in the lower layer is formed.
A via hole, ie, a photo via hole 50a connecting the second substrate 2 and the copper plating layer 70 on the surface is obtained (E in FIG. 8).
An appropriate circuit pattern or a group of pads may be formed on the copper plating layer 70 by a known photoetching method.

FIG. 9 shows a method of forming a laser photovia using a laser. In this method, first, a circuit pattern 62 is formed on the surface of the substrate 60 (FIG. 9A),
The thermosetting resin layer 80 is pressed on this. This resin layer 8
The copper foil 82 is laminated on 0 (FIG. 9B). Copper foil 8
2, a small opening 84 for a via hole and a predetermined circuit pattern are formed by a known photoetching method (C in FIG. 9).

From above the copper foil 82, a laser is irradiated in order toward each small opening 84 (FIG. 9D). Since the laser does not pass through the copper foil 82 on the surface, the thermosetting resin layer 80 is heated and disappears through the small opening 84 having no copper foil 82. As a result, a small hole 86 is formed below the small opening 84. Laser is the lower circuit pattern 6 made of copper foil
2, the lower circuit pattern 62 appears at the bottom of the small hole 86.

When copper plating 88 is applied to the laminate, a via hole for connecting the circuit pattern 62 and the copper foil 82, that is, a laser via hole 50b is formed by the copper plating layer on the inner surface of the small hole 86 (E in FIG. 9). . Copper foil 8 on the surface
2 and the copper plating 88 may be formed with a predetermined circuit pattern or pad group by a photoetching method or the like.

In the above embodiment, the first pad group 18
The first SMD 12 of the IP type is mounted, and the second pad group 26 is mounted.
Implements the second SMD 28 of the BGA type, but the present invention can of course be applied to other forms of SMD or those equipped with an SMD having only a different lead pitch.

[0024]

As described above, according to the first aspect of the present invention, one surface is connected to a surface mounting pad group (first pad group) of a printed wiring board, and the other surface has a different mounting form on the other surface. Since a mounting pad group (second pad group) is formed and an auxiliary laminate connecting both pad groups by an inner layer circuit pattern and via holes is provided, a printed wiring board is mounted when mounting surface mounting components having different mounting forms. There is no need to design and rework the whole. For this reason, it is possible to shorten the design time and to eliminate or simplify the preparation of the jig, thereby suppressing an increase in the production cost.

According to the second aspect of the present invention, there is provided a method for manufacturing a printed wiring board. In this case, by laminating the resin on the area where the auxiliary laminate is not formed (the area where the SMD is not mounted) via the release sheet, the lamination can be performed with a uniform pressure.

[Brief description of the drawings]

FIG. 1 is a perspective view of a printed wiring board used in the present invention.

FIG. 2 is an exploded perspective view showing an auxiliary laminate of the present invention.

FIG. 3 is an exploded perspective view showing one process during manufacturing.

FIG. 4 is a diagram showing an example of an inner layer circuit pattern.

FIG. 5 is an end view taken along line VV in FIG. 4;

FIG. 6 is a development view between pads 16A and 24A in FIG. 4;

FIG. 7 is a diagram showing a manufacturing process.

FIG. 8 is a process diagram of forming a photo via hole.

FIG. 9 is a process diagram of forming a laser via hole.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 printed wiring board 12 first SMD 14 lead 16 pad 18 first pad group 20 SMD mounting area 22 auxiliary laminate 26 second pad group 28 second SMD 30 release sheet 32, 34 insulating resin sheet (layer) 50 via hole 52 inner layer circuit pattern

Claims (3)

[Claims] 1. A printed wiring board for mounting a surface mounted component, wherein the printed wiring board is laminated on a partial area including a mounting area of the surface mounted component, and one surface is connected to a surface mounting component pad group of the printed wiring board. A printed wiring board comprising: a pad group for another surface mount component having a different mounting form formed on the other surface; and an auxiliary laminate connecting both pad groups with an inner layer circuit pattern and via holes. 2. A method of manufacturing a printed wiring board for mounting a surface mount component, comprising: a) laminating an insulating resin layer on a partial area including a mounting area of the surface mount component; and b) forming a via hole in the insulating resin layer. And c) repeating the steps a and b to form a surface mount component pad group of the printed wiring board on the surface of the uppermost insulating resin layer. A method for manufacturing a printed wiring board, wherein the method is connected to a component pad group. 3. The method for manufacturing a printed wiring board according to claim 2, wherein when laminating the insulating resin layer in step a) of step 2, the resin is laminated on a region other than the insulating resin layer via a release sheet.