JPS59232494A - Method of producing multilayer printed circuit board - 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] [Technical Field] The present invention relates to a multilayer printed wiring board! li! ! It is related to the method of sending.

[Background technology]

As a method for manufacturing multilayer printed wiring boards, the applicant has developed
To provide a method for manufacturing a multilayer printed wiring board, dated May 14, 2007, which allows multilayer wiring to be easily formed into a vr-shape, has high zero-conductivity, and can be manufactured at low cost. As shown in FIG. 1, this method uses a metal foil with an electrically insulating layer on which a first wiring pattern y(1) is formed on the surface of the wiring board 12) and a through hole (3) is formed on the wiring board 12). (4) are stacked and integrated so that the metal foil (6) is on the front side, and aligned with the through hole (3)?first wiring pattern i11 position (
Figure 1 (b)), then apply etching resist 16) on the surface of the metal foil (6) in a no-turn shape including through-hole lands (Figure 1 (C)), and then apply it to the construction site. metal foil (5) K second wiring pattern y i7
), and then after removing the 11υ and I resists (6) (Fig. 1(d)), the through holes (3) are filled with a conductive material (9) to form the first wiring pattern full. The second wiring pattern (7) is electrically connected (FIG. 1(e)). In the figure, 031 is an electrical insulating layer. However, this method does not allow through-holes (
3) Due to the slow hardening time of the etching resist (6) filled in the metal foil (51 ft.), the hardening time of the etching resist (6) was slow. Holland (1
0) has been etched and dried, and if the cyst 161 is to be thoroughly etched and hardened, a long drying time is required, which is a factor contributing to the cost of 71ν. Also, there was a drawback that it affected the pressure properties of the special plate.

[Purpose of the invention]

The present invention has been made in view of the above points, and is that when shaping the surface of a metal foil to form a wiring J\turn, one hole land is etched. It is an object of the present invention to provide a method for manufacturing a multilayer printed wiring board that can protect through-hole lands in a short time without causing damage to the through-hole lands. Wiring SSS taxi 1)
A through hole (3) is drilled in the wiring board (B212) Jl: and the IA foil (41) with an electrical insulating layer is placed on the VC layer so that the metal foil (5) is on the front side. 3) Align with the position of the first wiring pattern (1), and then apply etching resist (6) in a pattern shape to the surface of the metal foil (5), and make a through hole. The first wiring pattern fi+ and the metal foil (5) are electrically connected using solder (8) on the edge resist of Leland tio+, and then etched/)
VC to form metal foil (5) K second wiring pattern, I (7), then etch other than solder - J diresist: 6)
This objective has been achieved by a method for producing a multilayer printed wiring board, which is characterized by removing the .

The present invention will be explained in detail below. The wiring board (2) is not limited in any way, but may include, for example, a metal-based board, a plastic board, a flexible board, a single-sided board, a double-sided board, a double-sided through-hole board, etc. As shown in FIG. 2(a) VC, a spring pattern +11 is formed on the surface of the wiring board 4'1lii21 as shown in FIG. 2(b). As shown in Figure 2, the electrically insulating layered planning foil (4) with through holes 3) are stacked so that the metal foil (5) is on the front side and integrated. Align with the wiring pattern >Il,) position of Shiichiho+b13)&@1. Here, the electrical insulating layer (13) can be formed of a #J resin cloth layer, a sand lettering, or the like. Next, a patterned resist (6) is applied to the surface of the metal foil (5) so as to include the through holes (3) ((C) and (d) in the same figure). At that time, solder (8) is used as the 1-hole land (1ω's Kobo Sochi-7 and the cyst, and solder + 81
The VC electrically connects the first wiring pattern 7111 and the metal foil (5). Here, solder (8
) is a through-hole land (1
0) may be applied. Next, a @2 wiring pattern y (7) is formed on the metal foil (5) by etching. Here, as the pre-treatment liquid, ammonium persulfate solution and 'P
It is preferable to use a soft etch solution such as f17 potash solution. Of course, you can also use a commercially available dihydrogen acid solution, a phosphoric acid solution, and a concentrated sulfuric acid mixture, but if the solder (8) is exposed to the surface, there is a risk that the solder (8) will be corroded. Therefore, it is better to use Sochinji liquid. Next, the solder (etching resist 1G except for 81 ft) applied to the through hole land (10) is removed.

Therefore, the surface vc second wiring pattern y of the metal foil 15)
By using solder (8) as the etching resist (6) for hole land (101), through-hole land can be applied in a short time. (lO), and the solder (8) can be protected from the through-hole land (1
The through hole land (10) will not be peeled off from the through hole land (10) and the through hole land (10) will not be etched. ) The solder (8) filled in the through hole (3) conducts the first wiring pattern (1) and the metal foil (5), and then the second wiring pattern is applied to the metal foil (5). Wiring J\ter-
, (by forming 71k, the first wiring JS pattern y
11) and the second wiring butter y (7) by soldering (8
) can be electrically connected. In this way, a multi/im printed wiring board f can be manufactured by connecting the upper and lower wiring patterns ill F71. In addition, in the above embodiment, the multilayer wiring pattern (7) was formed only on one side of the wiring h (board (2)), but the wiring pattern (7) was formed on both sides. It's okay.

The present invention will be specifically explained below based on examples. ) A wiring pattern is formed for 2 minutes as shown in Fig. 2. Next, a copper foil with a thickness of 35 microns with an evo + resin layer with through holes drilled is placed on the top 1 m of the wiring board. The holes and wiring patterns were aligned and integrated into one layer. next,
Copper: After coating the surface of 1 with soldering resist and applying solder gold on the through-hole land, copper::11
Sex? A second wiring pattern was formed on the C4 and W foils by 7 steps, and then the etching resist other than the solder was removed, and the wiring pattern and the second wiring pattern: / were connected with solder. A multilayer printed wiring board was obtained.

The obtained multilayer printed wiring board had high reliability as the through-hole lands of the second wiring pattern were not etched, and could be manufactured in a short time and at low cost.

〔Effect of the invention〕

As shown in section h, the present invention applies an etching resist to the surface of the metal foil in a pattern shape, and also uses solder to the machining/sawching resist of the striped hole land to connect the first wiring no-turn and the metal foil 7. After electrical connection was made, a second wiring pattern was formed on the metal foil by etching, and then the etching resist other than the solder was removed, so the through-hole land was protected with solder and the through-hole land was finished. In addition to being able to prevent soldering, it also protects the stripe-hole land in a short time and contributes to cost savings.Moreover, it is possible to electrically connect the first wiring no-turn and the second wiring pattern with solder. can be done at the same time.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 (a) to (e) //i Partially cutaway sectional views showing the manufacturing method of the conventional example, and Fig. 2 (a3 to (e)) the manufacturing method of the present invention-embodiment. (1) is the first wiring pattern, (2) is the wiring foil board, (3
) is a through hole, (4) is a metal foil with electric insulation layer, (6
) is a metal foil, 161 is a process/rechinji resist, (7) is a second wiring pattern y, (8) is a solder, and 101 is a through pole land; jf) h. Agent Patent Attorney Ishi 1) Shi 7ij＞l!

Claims (1)

[Claims] (1) 900 pieces of metal with an electrically insulating layer on which a first wiring pattern is formed on the surface and through-holes formed on the wiring board are laminated and integrated so that the metal oil is on the surface. Align the through holes with the first wiring pattern, then apply etch resist to the entire pattern shape on the surface of the metal foil, and apply solder to the etching resist of the through hole land to form the first wiring pattern y. A method for manufacturing a multilayer printed wiring board, which comprises electrically connecting a metal 96, forming a second wiring pattern on the metal foil by etching, and then etching other than the solder to remove cysts.