JPH0730222A - Printed wiring board for multi-chip module mounting - Google Patents

Abstract

PURPOSE:To mount a high-density (ultra-high density) multi-chip module substrate on a printed wiring board by improving a connecting and fixing structure (bonding structure) between a printed wiring board and a multi-chip module substrate (MCM) having high-density connecting terminals. CONSTITUTION:On a multi-chip module substrate 30 mounting a plurality of IC chips 33a, 33b and 33c, an external terminal portion 31 and a plurality of electrodes 32 on the rear surface of said module substrate 30 are provided; and a plurality of electrode portions 12 and a plurality of electrode portions 32 provided on the corresponding multi-chip module substrate 30 are electrically connected and fixed on this multi-chip module mounting type printed wiring board.

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, and is mounted directly on a rigid printed circuit board having a structure similar to that of a normal printed circuit board, and an electrode portion and an external terminal portion on the surface of the base substrate and an electrode portion of an IC chip, respectively. By electrically connecting and fixing the electrodes and external terminals on the surface of the base substrate for a multi-chip module, the area where the electrodes and external terminals can be formed is expanded, and more electrodes and external terminals can be formed on the surface of the base substrate. There is a board-mounted multichip 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 to the above, the multi-chip module substrate having a high-density connection terminal and the printed wiring board have been improved in connection and fixed structure to prevent a reduction in the degree of freedom for pattern design, and a higher-density multi-chip module substrate. 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 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 a multi-chip corresponding to the plurality of electrode portions. The multi-chip module mounting type printed wiring board is characterized in that the plurality of electrode portions provided on the 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, a multi-chip module substrate 30 is mounted and fixed on a printed wiring board 10, and a printed wiring board 10 on which an energizing pattern is appropriately formed and formed on the surface of the printed wiring board 10. The window hole portion 2 in the region corresponding to the formed electrode portion 12 (for example, pad electrode portion).
0A is provided, and the frame-shaped TAB sheet 20 is laminated on the surface of the printed wiring board 10, and the multi-chip module substrate 30 is laminated on the TAB sheet 20 so as to cover the electrode portion 12. The external terminal portion 31 (lead terminal portion) formed on the back surface of the multi-chip module substrate 30 and the corresponding external terminal portion 21 (lead terminal portion) formed on the surface of the TAB sheet 20 are electrically connected and fixed to each other. The multi-chip module substrate 3
0 electrode part 32 formed on the back surface (eg pad electrode part)
The electrode portion 12 on the surface of the printed wiring board 10 corresponding to
The (pad electrode portion) is one that is connected and fixed so as to be able to conduct electricity.

The printed wiring board 10 has an energizing pattern (pattern wiring portion, lead terminal portion,
1 to a plurality of laminated inner layer boards each having a pad electrode portion and the like and an outer layer board laminated on the front and back sides thereof. The printed wiring board 10 includes the inner layer board or the outer layer board. Through holes and the like are formed on one surface or both surfaces for appropriately electrically connecting the respective conductive pattern layers on the front and back sides facing each other.

As shown in FIG. 1, at least an outer surface of a printed wiring board 10 according to an embodiment of the present invention is provided with an electrode portion 12 (pad electrode portion) in addition to a pattern wiring portion as an energizing pattern. An external terminal portion 11 (lead terminal portion) for electrically connecting to the outside is provided,
The external terminal portion 11 is the external terminal portion 2 of the TAB sheet 20.
1 (conductive pattern portion provided on the TAB sheet 20 entirely or partially in the form of a wiring pattern of an appropriate shape).

The TAB sheet 20 is a thin plastic sheet (film) on which a conductive pattern having an appropriate shape pattern is formed in advance by a photoetching method using a thin film conductive material.
Has a window hole 20a of an appropriate shape (rectangular shape or the like) for exposing the external terminal portion (lead terminal portion) of the energization pattern to the back side of the sheet.
A solder resist film (insulating film) or the like having an appropriate shape pattern for covering the energizing pattern and performing insulation protection is formed.

As shown in FIG. 1, on the surface of the TAB sheet 20 according to one embodiment of the present invention, at least an external part for electrically connecting to the outside is provided in addition to a pattern wiring part (not shown) as an energizing pattern. A terminal portion 21 (lead terminal portion) is provided, and the external terminal portion 21 is formed so as to slightly project inward from the end edge portion of the window hole portion 20a of the TAB sheet 20, and the lower printed wiring board. The external terminal portion 10 (lead terminal portion) of 10 can be contacted, and is electrically connected by soldering, gold bumps, or the like.

The multi-chip module substrate 30 is a multi-chip module base substrate 30a (a thin chip-like substrate having a wiring pattern similar to that of a printed wiring board or an electrode portion (pad electrode portion) formed on the back surface thereof, or a chip-like substrate). A plurality of integrated circuits 33a, 33b, 33c such as IC chips
... are mounted in high density, and as shown in FIG. 1, the multi-chip module substrate 30 in one embodiment of the present invention has a plurality of IC chips on at least the surface of the multi-chip module base substrate 30a. On the back surface of the multi-chip module base substrate 30a on which integrated circuits 33a, 33b, 33c, etc. are mounted, at least external terminals 31 (leads) for electrically connecting to the outside in addition to a pattern wiring section as an energizing pattern are provided. The terminal portion) and the electrode portion 32 (pad electrode portion) are provided.

As shown in FIG. 1, on the surface of the printed wiring board 10 having an external terminal portion 11 (lead terminal portion) and an electrode portion 12 (pad electrode portion), the electrode portion 12 (pad electrode portion) is formed. A window hole portion 20a is provided so as to surround the formed area, and an external terminal portion 21 (lead terminal portion) is provided on the surface thereof.
The frame-shaped (ring-shaped) TAB sheets 20 on which are formed are overlapped with each other, and the rigid type (hard) printed wiring board 10 and the flexible type (soft) TAB sheet 20 are appropriately provided in portions other than the energization pattern. They are bonded and fixed to each other with an adhesive to form a composite substrate.

From the upper side of the frame-shaped TAB sheet 20, a multi-chip module substrate 30 is superposed so as to cover the electrode portion 12 (pad electrode portion) of the printed wiring board 10, and external terminals on the surface of the TAB sheet 20. Part 21
(Lead terminal portion) and multi-chip module substrate 30
The external terminal portions 31 formed on the back surface of the are overlapped with each other, and are appropriately connected and fixed to each other by soldering, gold bumps, or the like.

The plurality of electrode portions 12 (pad electrode portions) of the printed wiring board 10 and the plurality of electrode portions 32 (pad electrode portions) of the multichip module substrate 30 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.

When connecting and fixing so as to be able to conduct electricity in the non-contact state, the gap 22 between the printed wiring board 10 and the base substrate 30a for the multi-chip module is
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-mentioned one embodiment of the present invention,
As shown in FIG. 1, the external terminal portion 1 of the printed wiring board 10
1 and the external terminal portion 3 of the multi-chip module substrate 30
1 are electrically connected to each other via a TAB sheet 20, but in the present invention, for example, the TAB sheet 20 is omitted and the external terminal portion 11 of the printed wiring board 10 is omitted.
And the external terminal portion 31 of the multi-chip module substrate 30.
And may be directly soldered and connected by a gold bump method or the like.

The multi-chip module mounting type printed wiring board of the present invention will be described in detail with reference to another embodiment of FIG. 2. The printed wiring board 10 and the multi-chip module substrate 30 are those used in the above-mentioned one embodiment. The same as can be used.

However, the TAB sheet 20 used has a frame shape (ring shape) in the above-described embodiment (see FIG. 1), but in this embodiment, as shown in FIG. 2, it is a thin plastic sheet. On the surface of the (film), an electrically conductive pattern of an appropriately shaped pattern is formed in advance by using a thin film conductive material by a photoetching method, etc., and an appropriate shape for exposing the terminal portion of the electrically conductive pattern to the back side of the sheet. A continuous sheet-shaped TAB sheet 20 in which a window portion 20a (rectangular shape or the like) is formed is used. In addition, a solder resist film (insulating film) having an appropriate pattern for insulating protection is formed on the energizing pattern.

The multi-chip module mounting type printed wiring board of the present invention will be described in detail below with reference to the other embodiment of FIG. 3. The printed wiring board 10 is used in the one embodiment and the other embodiments. The same as that used can be used.

However, in this embodiment, a multi-chip module substrate 30 mounted on the printed wiring board 10 is used.
3 has an external terminal portion 31 (lead terminal portion) on its surface, as shown in FIG.
External terminal portion 11 and multi-chip module substrate 30
The external terminal portion 31 is provided with an external connection portion 35 using a lead frame, a TAB sheet or the like so as to overlay the external terminal portion 31 on the multi-chip module base substrate 30a. Reference numeral 34 is a wiring pattern of an appropriate pattern formed on the base substrate 30a for the multi-chip module, and 36 is an IC chip 33, respectively.
a, 33b is a wire bond portion in which the external terminal portion 31 and the wiring pattern 34 are connected and connected.

In FIG. 3, the plurality of electrode portions 12 (pad electrode portions) of the printed wiring board 10 and the plurality of electrode portions 32 of the multichip module substrate 30 are the same as those in the above-described one embodiment and other embodiments. Are soldered to each other in a contact state or a non-contact state, and are electrically connected and fixed by an electric connecting portion 40 such as a gold bump. In this case, a plurality of electrode portions 12 corresponding to each other are provided. The self-alignment effect due to the surface tension of the solder, the gold bumps, etc. that melts between the overlapping of 32 is generated, and the corresponding electrode portions 12
The electrode part 32 and the electrode part 32 can be connected and fixed in a state where they are self-registered to each other.

Further, for example, when the plurality of corresponding electrode portions 12 (pad electrode portions) and the electrode portion 32 are connected and fixed in a non-contact state so that they can be energized, the printed wiring board 1
0 and the multi-chip module base substrate 30a in the gap 22 with an anisotropic conductive resin film of appropriate thickness (conductive resin film having electrical conductivity only in the film thickness direction) sandwiched and fixed. In addition, the external connection portion 35 is provided with respect to the external terminal portions 11 and 31.
Soldering, gold bumps, carbon dioxide laser, YAG
It can be electrically connected and fixed by thermal fusion using a laser or the like.

[0026]

According to the present invention, the multichip module substrate 30 is placed on the printed wiring board 10 so as to be superposed on each other, and the plurality of electrode portions provided on the printed wiring board 10 and the external portions provided on the multichip module substrate 30 are provided. The terminal portion and a plurality of electrode portions provided on the back surface thereof are electrically connected to each other, and the plurality of electrode portions necessary for the multichip module substrate 30 utilize at least the back surface side of the substrate. Since it is formed by utilizing both the front and back surfaces of the substrate as necessary, the electrode portion of the multi-chip module substrate 30 and the outside can be compared with the case of forming only on the front surface side as in the conventional case. Since the degree of pattern integration (number, number) of terminals and the like is increased or the formation density of the electrodes is eased, IC chips that can be mounted on the multi-chip module substrate 30 are In which the number of possible increases.

The plurality of electrode portions and external terminal portions corresponding to each other can be electrically connected and fixed by soldering, gold bumps, TAB sheet (TAB lead) or the like, and the printed wiring board 10 main body and the multi-chip module can be connected. The substrate 30 main body can be firmly bonded and fixed to each other using an anisotropic conductive film or an adhesive such as an epoxy resin.

Further, for example, as shown in one embodiment (see FIG. 1) and another embodiment (see FIG. 2), the electrode portion 12 (pad electrode portion) formed on the surface of the printed wiring board 10 is used.
A window-shaped portion 20a is provided in a region corresponding to the above, and a frame-shaped or sheet-shaped TAB sheet 20 is provided on the surface of the printed wiring board 10, and the electrode portion 12 (pad electrode) is provided on the TAB sheet 20. Since the multi-chip module substrate 30 is overlapped so as to cover the TAB sheet 20, the TAB sheet 20 corresponding to the external terminal portion 31 (lead terminal portion) formed on the back surface of the multi-chip module substrate 30.
The external terminal portion 21 (lead terminal portion) formed on the front surface can be electrically connected and fixed to each other, and the printed wiring board 10 corresponding to the electrode portion 32 (pad electrode portion) formed on the back surface of the multichip module substrate 30. Surface electrode part 12
The (pad electrode portion) and the pad electrode portion can be connected and fixed so as to be electrically conductive.

Further, for example, as shown in another embodiment (see FIG. 3), the multi-chip module substrate 3
When the external terminal portion 31 of 0 is formed on the surface of the multi-chip module base substrate 30a,
The external connection portion 35 can be used to electrically connect and fix the external terminal portion 11 of the printed wiring board 10.

[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. When mounting on a normal printed wiring board on which a multi-layer wiring pattern and a plurality of electrodes are formed, the multi-chip module board to be used may be the back side of the board or both front and back surfaces of the board. Since a plurality of electrode parts and external terminal parts are provided by utilizing the above, it is possible to increase the degree of freedom in designing the wiring pattern of the electrode parts, the external terminal parts and the like.

In addition, a high density multi-chip module substrate on which more IC chips are mounted than the conventional one is provided with a general block semiconductor integrated circuit (LSI) having a plurality of leg-shaped metal lead terminals as in the conventional one. Can be mounted on the printed wiring board by a connection method different from the method of mounting the.

In the multi-chip module mounting type printed wiring board of the present invention, a high density multi-chip module substrate having a super-large number of mounting connection electrode portions and external terminal portions is connected to the super-large number of wiring board sides. When electrically connecting and mounting in correspondence with the 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 connecting and fixing operation.

The multi-chip module substrate 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 condition of the wiring pattern such as each electrode portion and 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 making it easier.

[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.

FIG. 3 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]

DESCRIPTION OF SYMBOLS 10 ... Printed wiring board 11 ... External terminal part 12 ... Electrode part 20 ... TAB sheet 20a ... Window hole part 21 ... External terminal part 22 ... Gap part 30 ... Multichip module substrate 30a ... Base substrate 31 ... External terminal part 32 ... Electrode Part 33a, 33b, 33c ... IC chip
34 ... Wiring pattern 35 ... External connection part 36 ... Wire bond part 40 ... Electrical connection part

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 has an external terminal portion and a plurality of electrode portions on the back surface of the multi-chip module board. And at least the plurality of electrode portions provided on the printed wiring board and the plurality of electrode portions provided on the back surface of the multi-chip module substrate corresponding to the plurality of electrode portions are electrically connected and fixed to each other. A multi-chip module mounting type printed wiring board characterized in that 2. A plurality of electrode portions provided on the printed wiring board and a plurality of electrode portions provided on the back surface of the multichip module substrate corresponding to the plurality of electrode portions are made of a conductive resin film. The multi-chip module-mounted printed wiring board according to claim 1, which is electrically connected and fixed.