JPH0730055A - Multichip module-mounted printed wiring board - Google Patents

Abstract

PURPOSE:To improve a connection fixing structure (junction state) so as to mount a multichip module board (MCM) possessed of connection terminals of high density on a printed wiring board. CONSTITUTION:An external terminal 21 is provided to a multichip module board 20, electrodes 22 are provided to the rear of the multichip module board 20, electrodes 12 provided onto a printed wiring board 10 are electrically connected and fixed to the corresponding electrodes 22 provided onto the rear of the multichip module board 20, the multichip module board 20 is fitted into a pit 13 provided to the surface of the printed wiring board 10, and thus a multichip module-mounted printed board can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-chip module constructed by mounting a plurality of chip-shaped semiconductor integrated circuits (IC chips, etc.) on a single substrate at high density on a printed wiring board. The present invention relates to a mounted multi-chip module mounting type printed wiring board.

[0002]

2. Description of the Related Art Conventionally, the miniaturization of electronic equipment, the digitization of circuits, or the accompanying semiconductor integrated circuit (LS)
In order to cope with the progress of the I) in the widespread use, a plurality of semiconductor chips such as IC chips are mounted on one small-sized rigid board for module (hard board for module) and mounted at high density. A rigid board type multi-chip module (MCM) that realizes one functional block has been put into practical use. With such a multi-chip module (hereinafter referred to as a multi-chip module board), a so-called 1
Two large-scale semiconductor integrated circuits can be formed, and there is an advantage that a large-scale semiconductor integrated circuit can be realized with a small size and high density.

For example, as the above-mentioned conventional multi-chip module, an IC chip and a multi-chip module substrate are mounted on a multi-chip module substrate on which chip-shaped semiconductor integrated circuits such as IC chips are mounted on an island portion of a lead frame. Each electrode part, the inner lead part of the lead frame, and the external terminal part of the multi-chip module substrate are bonded and electrically connected by using a gold wire (wire), and then the periphery thereof is molded with resin. There is a resin-molded multi-chip module having a plurality of leg-shaped external terminals (lead terminals) of the above structure on its side part.

In addition, as a conventional multi-chip module, in order to further increase the density of the multi-chip module, a plurality of IC chips themselves are used as a small base substrate for a multi-chip module (single layer or multilayer wiring pattern). , A surface type electrode, a surface type external terminal and the like, which is mounted on a rigid type substrate having a structure similar to that of a normal printed wiring board, and the electrode part and the external terminal part on the surface of the base substrate and the electrode part of each IC chip. By electrically connecting and fixing and, it is possible to expand the formable area of the electrodes and external terminals on the surface of the base substrate for the multi-chip module, so that more electrodes and external terminals can be formed on the surface of the base substrate. There is a board-mounted multi-chip module.

[0005]

In recent years, it has been required to further densify the above-mentioned multi-chip module into a higher density or ultra-high density. When the mounting density is increased by increasing the number of IC chips arranged on the multi-chip module base substrate in order to increase the density, the electrode portion or the external terminal on the surface of the multi-chip module base substrate is correspondingly correspondingly increased. The formation area of the parts is narrowed, the formation density of the electrode parts and the external terminal parts per unit area of the base substrate is naturally increased, and the degree of freedom for pattern design is reduced. Since it is impossible to form electrodes and external terminals, a collection of IC chips can be mounted on the surface of the base substrate for multichip modules. Number to those that limit occurs.

According to the present invention, in a multi-chip module mounting type printed wiring board, the number of integrated IC chips that can be mounted on the surface of a multi-chip module base substrate can be increased from the current level, and the multi-chip module substrate can be further densified. In addition, by improving the connection and fixing structure between the multi-chip module board having high-density connection terminals and the printed wiring board, it is possible to prevent a reduction in the degree of freedom for pattern design and to achieve a higher-density multi-chip module board. Is to be mounted on a printed wiring board.

[0007]

The present invention provides a multi-chip module mounting type printed wiring board in which a multi-chip module substrate is mounted and fixed on a printed wiring board.
The multi-chip module mounting type printed wiring board is characterized in that the multi-chip module substrate is fitted and fixed in a pit provided on the surface of the printed wiring board. The present invention, in the above invention, the multi-chip module substrate is provided with an external terminal portion and a plurality of electrode portions on the back surface of the multi-chip module substrate, at least a plurality of electrode portions provided on the printed wiring board,
In the multi-chip module mounting type printed wiring board, the plurality of electrode portions and the plurality of electrode portions provided on the back surface of the corresponding multi-chip module substrate are electrically connected and fixed to each other.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A multi-chip module mounting type printed wiring board of the present invention will be described in detail with reference to one embodiment of FIG.

As shown in FIG. 1, the multi-chip module substrate 20 has a plurality of IC chips 23a,
23b and 23c (semiconductor integrated circuits; LSI) are mounted, an external terminal portion 21 is provided on the front surface of the multichip module substrate 20, and a plurality of electrode portions 22 are provided on the back surface.
Is provided.

The printed wiring board 10 is a single-layer or multi-layer base substrate 10a constituting the printed wiring board 10.
The surface is provided with a recessed pit 13 for fitting the multi-chip module substrate 20.

An external terminal portion 11 on the printed wiring board 10 side is partially provided along the outer periphery of the pit 13 on the surface of the printed wiring board 10. The inner bottom portion of the pit 13 has a plurality of electrode portions on the printed wiring board 10 side. It has twelve.

The multi-chip module mounting type printed wiring board of the present invention has the multi-chip module substrate 20 fitted in the pit 13 of the printed wiring board 10, and the surface of the printed wiring board 10 and the multi-chip module. It is suitable that the surface of the substrate 20 and the surface of the substrate 20 are substantially flush with each other.

By fitting the multi-chip module substrate 20 in the pits 13 of the printed wiring board 10, the conductive patterns are formed on the bottom surface of the pits 13 of the printed wiring board 10 in which a proper energizing pattern is formed over a single layer or multiple layers. On the plurality of electrode portions 12, correspondingly, the plurality of electrode portions 2 provided on the back surface of the multi-chip module substrate 20.
2 are arranged so as to face each other and are electrically connected and fixed to each other, and the external terminal portion 11 partially provided along the outer peripheral portion of the pit 13 of the printed wiring board 10 and the external portion provided on the surface of the multichip module substrate 20. The terminal portion 21 and the terminal portion 21 are arranged adjacent to each other (close to each other), and are electrically connected and fixed to each other using an external connection portion 25 such as a TAB sheet, a lead wire, or a gold wire wire bond.

In the TAB sheet, a thin plastic sheet (polyimide resin film) is preliminarily formed with a conductive pattern of a shape pattern by a photo-etching method using a thin film conductive material, and the conductive pattern is appropriately selected. The external terminal portion is exposed to the back side of the sheet so that it protrudes from the edge of the sheet, or the sheet is formed with a window hole of an appropriate shape (rectangular shape, etc.), continuous sheet shape, small piece sheet shape, ring shape, etc. The wiring member and the wiring member, and a solder resist film (insulating film) or the like having an appropriate shape pattern for insulating protection is formed on the energizing pattern.

The printed wiring board 10 is composed of one or a plurality of laminated inner layer boards and outer layer boards laminated on the front and back sides thereof, and has a single-layer or multi-layer pattern wiring portion having an appropriately shaped pattern, and an outer layer board. A substrate having an external terminal portion 11 (lead terminal portion) on its surface and a conductive pattern such as a plurality of electrode portions 12 (pad electrode portions) formed on the inner bottom surface of a pit 13 such as an inner layer plate (for example, about 300 mm square to 500 mm square) The printed wiring board 10 is provided with through holes or the like for appropriately energizing and connecting the respective energization pattern layers formed on one surface or both surfaces of the inner layer board or the outer layer board on the front and back sides facing each other. . The external terminal portion 11 may be formed of a TAB sheet laminated on the surface of the rigid printed wiring board 10.

As with the printed wiring board 10, the multi-chip module substrate 20 has a wiring pattern, an external terminal portion 21, and a plurality of electrode portions 22 (pad electrode portions) formed on a single-layer or multi-layer base substrate 20a for a multi-chip module. A plurality of ICs on a thin rigid type substrate (hard substrate) in the form of small pieces or chips (larger than an IC chip, for example, 20 mm square to 50 mm square, thickness about 2 mm)
The integrated circuits 23a, 23b, 23c ...
The multi-chip module substrate 20 according to the embodiment of the present invention is mounted on at least the surface of the multi-chip module base substrate 20a as shown in FIG. Integrated circuits 23a, 23b such as individual IC chips,
23c is mounted, and on the surface of the multi-chip module base substrate 20a, at least an external terminal portion 21 (lead terminal portion) for electrically connecting to the outside is provided in addition to the pattern wiring portion serving as the current-carrying pattern. Is provided with a plurality of electrode portions 22 (pad electrode portions).

Further, a plurality of electrode portions 12 (pad electrode portions) of the printed wiring board 10 and a plurality of electrode portions 22 (pad electrode portions) of the multichip module substrate 20 corresponding thereto are in contact with each other, Alternatively, they are connected and fixed in a non-contact state so that they can be energized with each other.

In the case of connecting and fixing so as to be able to conduct electricity in the non-contact state, in the gap portion 14 between the printed wiring board 10 and the base substrate 20a for the multichip module,
Anisotropic conductive resin film (conductive resin film that conducts electricity only in the film thickness direction) can be sandwiched and fixed, but in addition, it can be soldered or electrically connected with gold bumps. You may make it join and fix.

Further, in the above-described embodiment of the present invention, as shown in FIG. 1, the external terminal portion 11 of the printed wiring board 10 is provided.
The external terminal portion 21 of the multi-chip module substrate 20 and the external terminal portion 21 of the multi-chip module substrate 20 are electrically connected to each other through the external wiring portion 25. The external wiring portion 25 using the external terminal portion 11, the TAB sheet, the lead wire or the like. The external terminals 21 are electrically connected and fixed to each other by direct soldering, gold bump method, or thermal laser method (carbon dioxide gas laser, YAG laser).
Etc. can be connected.

Next, the multi-chip module mounting type printed wiring board of the present invention will be described in detail according to another embodiment of FIG.

As shown in FIG. 2, the multi-chip module substrate 20 has a plurality of IC chips 23a,
23b and 23c (semiconductor integrated circuit; LSI) are mounted, and an external terminal portion 21 and a plurality of electrode portions 22 are provided on the back surface of the multichip module substrate 20.

The printed wiring board 10 is a single-layer or multi-layer base substrate 10a constituting the printed wiring board 10.
A recessed pit 13 for fitting the multi-chip module substrate 20 is provided on the surface, and an inner terminal portion of the pit 13 is provided with an external terminal portion 11 on the printed wiring board 10 side and a plurality of electrode portions 12. ing.

Further, the multi-chip module substrate 20
Like the printed wiring board 10 shown in the above-described embodiment, the wiring pattern, the external terminal portion 21, and the plurality of electrode portions 22 (pad electrode portions) are formed on the single-layer or multilayer base substrate 20a for a multi-chip module. Formed small pieces, chips (larger than IC chips, for example, 20 mm
It is a thin rigid type substrate (hard substrate) of square to 50 mm square and a thickness of about 2 mm), and a plurality of IC chips or other integrated circuits 23a, 23b, 23c ... However, in another embodiment, the multi-chip module substrate 20 has a plurality of integrated circuits 23a, 23b such as IC chips on at least the surface of the multi-chip module base substrate 20a. , 23c are mounted, and on the back surface of the multi-chip module base substrate 20a, in addition to the pattern wiring part as the energizing pattern, at least an external terminal part 21 (lead terminal part) for energizing and connecting to the outside, and a plurality of The electrode portion 22 (pad electrode portion) is provided.

In the multi-chip module mounting type printed wiring board of another embodiment shown in FIG. 2, the multi-chip module substrate 20 is fitted in the pit 13 of the printed wiring board 10 as in the above-mentioned embodiment. The surface of the printed wiring board 10 and the multi-chip module substrate 20.
It is appropriate that the surfaces are substantially flush with each other, and the multichip module substrate 20 is fitted into the pits 13 of the printed wiring board 10 so that the conductive pattern can be appropriately applied over a single layer or multiple layers. Correspondingly, a plurality of electrode portions 22 provided on the back surface of the multi-chip module substrate 20 are arranged so as to face each other on the plurality of electrode portions 12 on the inner bottom surface of the pit 13 of the printed wiring board 10 on which is formed. External terminals 11 that are connected and fixed to each other so that they can be energized and that are provided on the bottom surface inside the pit 13 of the printed wiring board 10 and external terminals 21 that are provided on the back surface of the multichip module substrate 20 are arranged so as to face each other. They are connected and fixed so that they can conduct electricity.

The plurality of electrode portions 12 (pad electrode portions) of the printed wiring board 10 and the corresponding plurality of electrode portions 22 (pad electrode portions) of the multi-chip module substrate 20 are in contact with each other or not. In the contact state, they are electrically connected and fixed to each other, and the external terminal portion 11 of the printed wiring board 10 and the corresponding external terminal portion 12 of the multi-chip module substrate 20 are in contact with each other or in the non-contact state with each other. It is connected and fixed so that it can be energized.

In the case of connecting and fixing so as to be able to conduct electricity in the non-contact state, in the gap portion 14 between the printed wiring board 10 and the base substrate 20a for the multichip module,
Anisotropic conductive resin film (conductive resin film that conducts electricity only in the film thickness direction) can be sandwiched and fixed, but in addition, it can be soldered or electrically connected with gold bumps. You may make it join and fix.

[0027]

According to the multi-chip module mounting type printed wiring board of the present invention, the multi-chip module substrate 20 is fitted and placed in the pit 13 of the printed wiring board 10,
The external terminal portion 11 provided on the printed wiring board 10, the external terminal portion 21 provided on the multichip module substrate 20, and the electrode portion 1 provided in the pit 13 of the printed wiring board 10.
2 and at least a plurality of electrode portions 22 provided on the back surface of the multichip module substrate 20 are electrically connected so as to correspond to each other, and the plurality of electrode portions necessary for the multichip module substrate 20 are at least Since it is formed by utilizing the back side of the substrate 20, that is, by utilizing both the front and back sides of the substrate 20 as necessary, compared to the case of forming only on the front side as in the related art, Since the degree of pattern integration (the number and the number) of the electrodes and external terminals of the chip module substrate 20 is increased or the formation density of the electrodes is relaxed, the IC chip (23a) that can be mounted on the multi-chip module substrate 20 is reduced. , 23b, 23
The number of c) can be increased more than before.

Further, a plurality of electrode portions 12 corresponding to each other,
22, the external terminal portion 21 and the plurality of electrode portions 11 can be electrically connected and fixed by soldering or gold bumps,
The main body of the printed wiring board 10 and the main body of the multi-chip module substrate 20 can be firmly bonded and fixed to each other using an anisotropic conductive film or an adhesive such as an epoxy resin.

Further, according to the multi-chip module mounting type printed wiring board of the present invention, the size of the pits 13 formed in the printed wiring board 10 is set to a size in which the multi-chip module substrate 20 can be closely fitted. By fitting the multi-chip module substrate 20 into the pit 13 and simultaneously
It is possible to position and fix the.

[0030]

According to the multi-chip module mounting type printed wiring board of the present invention, a high-density multi-chip module board in which a plurality of IC chips are mounted on one small-sized module board is used. , A general block-shaped semiconductor integrated circuit provided with a plurality of leg-shaped metal lead terminals as in the conventional case when mounted on a normal printed wiring board on which a multilayer wiring pattern and a plurality of electrodes are formed) It is possible to mount a high-density multi-chip module substrate on a printed wiring board by a connection method different from the method of mounting (LSI) on the printed wiring board without reducing the freedom for pattern design. Become.

Further, the multi-chip module mounting type printed wiring board of the present invention comprises a high density multi-chip module substrate provided with a super-large number of mounting connection electrode portions and external terminal portions on the same side as the super-large number of printed wiring board sides. When electrically connecting and mounting in correspondence with the connection electrode portion (including the external terminal portion), there is an effect that the mounting and fixing can be performed with good precision and accuracy in the connection fixing operation.

The multi-chip module board mounted on the multi-chip module mounting type printed wiring board of the present invention should not be subjected to resin molding for exterior packaging from the upper side of each IC chip mounted on the surface thereof. From the outside, the wiring state of the wiring pattern such as each electrode portion and the external terminal portion provided on the surface of the multi-chip module substrate and the conduction state between the electrode portion and the external terminal portion and the IC chip are inspected from the outside. It has the effect of facilitating.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of a multi-chip module mounting type printed wiring board according to an embodiment of the present invention.

FIG. 2 is a schematic side sectional view of a multi-chip module mounting type printed wiring board according to another embodiment of the present invention.

[Explanation of symbols]

Reference numeral 10 ... Printed wiring board 10a ... Base substrate 11 ... External terminal portion 12 ... Electrode portion 13 ... Pit 14 ... Gap portion 20 ... Multichip module substrate 20a ... Base substrate 21 ... External terminal portion 22 ... Electrode portion 23a, 23b, 23c ... IC chip
25 ... External connection

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location H05K 7/02 H 7301-4E (72) Inventor Toshio Obo 1-5 Taito, Taito-ku, Tokyo No. 1 Toppan Printing Co., Ltd.

Claims (2)

[Claims] 1. A multi-chip module mounting type printed wiring board in which a multi-chip module board is mounted and fixed on a printed wiring board, wherein the multi-chip module board is fitted and mounted in a pit provided on the surface of the printed wiring board. A multi-chip module mounting type printed wiring board, which is fixed. 2. The multi-chip module substrate is provided with an external terminal portion and a plurality of electrode portions on the back surface of the multi-chip module substrate, at least a plurality of electrode portions provided on the printed wiring board, and the plurality of electrodes. 2. The multi-chip module mounting type printed wiring board according to claim 1, wherein the parts and the corresponding plurality of electrode parts provided on the back surface of the multi-chip module substrate are electrically connected and fixed to each other.