JPS5954297A - Method of producing green sheet 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 [Technology 9 to which the invention pertains]
! 2. Alternate printing and drying f: Repeatedly laminating and sintering in a 1.611 original atmosphere furnace to form a specific circuit function-2, or mold etc. on a green sheet (unsintered aluminum boot tape) After forming the conductor L on the press, the conductor paste is completely printed and dried (12), and multiple green sheets are laminated with pressure and bonded in a reducing atmosphere furnace.
2) Method for manufacturing a green sheet printed circuit board (4).

[Prior art and its problems]

In recent years, the demand for smaller, lighter, and more reliable electronic equipment has been increasing in various fields, and in order to satisfy these demands such as λ1, high-density multilayer wiring boards such as alumino ceramic - with electronic functional elements; <, 7. A so-called multi-step packaging technology is being developed in which a plurality of chip components, such as IC chips, are fixed to a support plate and the whole is sealed. Green Minnow is one of the forming methods for high-density multilayer wiring boards for multi-boot package.
) (unsintered alumina tape)”-11f Vl
, M , + , , Mn conductor paste and alumina taste paste are alternately printed and dried. The conductive holes are formed by the so-called green sheet printing lamination method to form the circuit function in the area, or by a method such as printing a mold on the green sheet (unsintered alumina tape). After forming 1-thickness, conductor pastes such as W, M(,, bln, etc.) are printed, dried, laminated and pressed with several sheets of green sheets, and sealed in a reducing atmosphere furnace. A certain amount 15
The so-called green sheet private layer that forms the circuit function of 1iL
, etc. are being developed. As shown in Fig. 1(a), the +111 configuration of the front m1 conductor/combined pattern of the high-carved 1 degree multilayer wiring board is I10 for input/output terminals.
Bad J-7, Q+F, air-tight hole for air-tightly sealing the entire bump part 6-1: stopper seal link turn 1-2, kth die-ponding pad 1 for supporting and fixing chip components From the eighth 7th point lead bonding pad No. 4 ■, where wire bonding such as ATR wire is performed to form an electrical connection between chip components such as -3 and IC chips and the high-density multilayer wiring board 1-5. It has become. Figure 1(b) shows the cross-sectional view. 1-6 is a clean sheet (unsintered alumina tape), which becomes an alumina ceramic by sintering in a reducing atmosphere furnace. 1-7 is a printed insulating paste such as alumina paste, 1-8 is a printed insulating paste such as W
.

It is a grid paste with MO+Mrr@ printed on it.

In such a high-density multilayer wiring board, after sintering in a reducing atmosphere furnace, it is necessary to apply a solder to the seal ring turn 1-2 to improve the properties. BONDING TSUTT.

1-4, in order to improve wire bonding properties with Au wires, etc., it is common practice to plate a cotton material such as Au with a thickness of several μIn. Plating a conductor such as Ni to a thickness of several μm 1
- is generally done A) - [I/X].

Here, 1-9 is a plated layer of Ni etc. as a single adhesion layer, and 1-10 is a plated layer (θ) with a solder (for good lability or wire bonding property -4-) 3, the problem in this case is:
Arrow Al in FIG. 1(a): 21
In the case of the conductor node ζ in Table 1111 above, which is connected from the 10 pad 1-1 by the lower wiring (indicated by the dotted line), I10
A plating electrode is connected to the pad 1-1, and a plating layer 1-9, which is an RiJ adhesive layer, and a plating layer for improving the bonding properties or wire bonding properties are formed by electrolytic plating. 1-10, but as shown by arrow B in FIG. 1(a), -F layer wiring (
For example, if there are many wirings inside the seal ring 1-2 (shown by dotted lines) that are connected only to the outer lead bonding pads 1-4, the above-mentioned connections will be placed on the surface conductor pattern. Plating layer 1 as 71 layer
-9 and the plated layer No. 10 to improve solderability or wire bonding properties are formed by electrolytic plating. Even if the plating electrode comes into contact with the part (l/), it is almost impossible to do so because the plating film does not have any fine stones. Arrow B) The wiring board 1-5 is exposed to the product I, and the plated layers 1-9, 1-'10 are removed by electrolytic plating.
It was impossible to form this on all surface conductor patterns. As a method to solve these 05 problems, C is a niJ plated layer 1-9゜1-1 by electroless plating method.
For example, electroless plating of Au is technically difficult. In particular, in order to improve the bonding properties of Au wire, etc., at least 1.
The thickness of the plating layer 1-10 is about 5 μn.
-The process is very complicated and requires two steps, and the process for Au is 11! (There were drawbacks such as the electrolytic plating solution being very expensive.

[Objective of Invention 1] The present invention has been made in view of the above circumstances, and its object is to realize all surface pattern tables i+i1+ of Green Sea River and printed wiring boards. ＝The electrolytic plating method is used to form a plating layer as an adhesion layer and a plating layer for good solderability or wire bondability at any time.
The goal is to become capable.

[Summary of the invention]

That is, the present invention involves the process of printing the top layer printed conductor pattern on the entire surface of a green sheet multilayer wiring board, sintering it in a reducing atmosphere furnace, and then applying an adhesive layer such as Ni to the entire surface by electrolytic plating. The conductor plating layer and soldering are made using NuA for good wire punch and ink properties. Forming a ring plating layer on I-1, coating I-1 with photosensitive resist 2, coating A on I-1, drying, exposing and developing the front surface girder pattern, 2. Remove unnecessary portions other than the surface conductor pattern formed on the entire surface 11f1 by sequentially etching away the L-shaped A layer and the conductor print layer. It is characterized by having 7 degrees. .

〔Effect of the invention〕

With the IIH which adopts the present invention, there is no need to use electroless Au0'+l remating, which has been difficult in the past, and the complicated process and IG
It is no longer necessary to use an expensive electroless plating solution, and it is now possible to manufacture green sheet printed wiring boards at low cost. In addition, with the progress of higher density, there are four independent conductor patterns inside the board.No matter how many IR surface conductor patterns increase, there is a coexistence problem. Face facing shi j′; one body putter
4. It is possible to form a plating layer on the 2nd part of the 4th part.

[Embodiments of the Invention] An example of the present invention will be described below with reference to the drawings. Fig. 2 (gl is according to the present invention) shows a 1ir + 1 diagram of each upper (green in 2) printed wiring board. Here 2-1 is green;, y-
) is NJ\t7. ;C214. 'An example of F layer is W, Mo.

2) indicates a printed conductor layer such as Mn, and 2-3 indicates an insulating printed layer below the alumina paste. 2-4 is the body layer with the i1ith i'4 of the table, and 2
-5 is a cotton body layer made of Ni etc. as adhesive 1~,
In addition, 2-6 is for example AII to improve the solder bonding process.
Q': 1'l glare plated layer. 2-7 is photosensitive resin 5. ;□; indicates a film. , 7(', Figure 2(a) shows the top layer 8 et al. (body butter'-/ for example W,
MO, ・Mu Bamboo sheet:) (shows the state in which one sheet of body paste is printed on the entire surface t2-(-, after sintering this in a source atmosphere tank fF, Fig. 2 (1)) Please accept <
1 (7i on the entire surface of the song), 4゛ by deplating method) "2"
"Oha,,j,I
+ Noip% body plating/, %j 2-. 5 in the form p5',
"J-/, + t, S C) (knee 2nd figure (0(-
Showing 1-Like hanging (] (dimensional o) Rui number; l A, t
If-12-6 Wire bonding property of + wire etc. is 1;!, good example of conductor of EAL hook” If-12-6
Table 1 (formed by plating method with 1↓ on the entire surface of 11, photosensitive resist 2-7'' on 71<3-uD hollow in Figure 2 (d); C coating/
'After this, as shown in Figure 2(e), the surface conductor layer 7 of the high-density multilayer wiring board and wave to be formed is exposed and developed, and the surface conductor layer 7 is formed on the entire surface as shown in Figure 2(f). f Table jj+i Conductor r in the pissy part other than the conductor pattern... The conductor plating layer 2-6, adhesive layer and New conductor plating layer 2
-5, Full-surface solid printing surface conductor layer 2-1 and jII order j-
Sobung is removed and transferred to C as shown in Figure 2 (g).
By peeling off the raw resist 2 and -7, the highest layer conductor pattern is formed according to the rules of practice.
According to 1, electroless plating method is used, without using 4-41,
η1゜ Easily green by using the decoupled plating method; note mark l] It is now possible to form conductor patterns on the surface of the wiring board 7 (-〇

[Brief explanation of drawings]

Fig. 1 C explains the conventional example - Lv) Fig. 4'Ny
2 (a) to (g) show the manufacturing process of the green, sheet-marked A11ll wiring board according to the present invention] Step 2 11) I-plane view O2-1.
F I←q) Conductor pattern, 2-3/lower No. 8 Jl'
j Red rest pattern body, 2-4... the lowest layer surface! 1 body pattern', 2 6... 1 piece conductor plating layer as 1 piece, ? -6...ノ ngtojυ) J, 'lrui LJ
W・F key bond 1 f 1 item [(NaI, j';i,
2-7...photosensitive L/l') strike. (7317) Proxy agent
1 stone (t・１力・ji１）to l Figure c〃su (1,) Figure 2 Figure 2

Claims (1)

[Claims] A conductor paste and an insulator base are alternately printed on a green sheet, dried repeatedly, and then sintered in an L7 reducing atmosphere furnace to form a specific circuit function, or to form a mold on a green sheet. After forming the conductive holes in the press, printing and drying the conductor paste, press the multiple sheets of green seals in a selective layer and sintering in a reducing atmosphere furnace to form a specific circuit function on the small C9L. Green V-
) In the method for manufacturing a printed wiring board, the steps include printing the topmost 2n layer on the entire surface, and after sintering in a reducing atmosphere furnace,
The conductor plating layer as an adhesive layer and the conductor plating layer as a conductor layer to improve wire bonding properties or solderability are applied to the entire surface of the uppermost conductor layer using the electrolytic plating method. After the process of forming the entire surface on the printed solid layer, coating and drying the photosensitive resist, and exposing and developing the top layer conductor pattern, the conductor plating layer as the adhesive layer and wire bonding property are made good, or soldering is made easy. Step 2 to form a top layer conductor pattern by sequentially etching away unnecessary conductor parts other than the top layer turns of the R-shaped row body plating layer and the entire printed solid conductor layer to improve the conductor layer. A method for producing a green printed wiring board characterized by: