JPH01129449A - Multichip module and module substrate therefor - Google Patents

Abstract

PURPOSE:To improve a module function such as the increase of computing speed, to eliminate the need for a special cooling system at the time of inspection and to simplify an inspection process by forming a pad for changing inspection-technique onto the rear of a substrate and a power bus onto the surface of the substrate. CONSTITUTION:Since pads 50 for changing inspection-technique are arranged onto the rear of a substrate, chips 10 can be disposed in density higher than the pads have been arranged around the chips 10 by 40-50%. On inspection, a probe for inspection can be connected from the rear direction or the substrate, and a module can be inspected under the state of the assembled module. Consequently, a special cooling system need not be prepared on inspection. The probe for inspection is positioned easily to the pads 50 for changing inspection- technique disposed on a plane. The easy positioning of the probe for inspection also results in the connection of a technique varying wiring 60. For arrange the pads 50 for changing inspection-technique onto the rear of the substrate, input/output pins 35 are placed around a module substrate 30 and a power system onto the surface of the substrate as power buses 40.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multi-chip module mounting a plurality of semiconductor elements (hereinafter referred to as LSI chips) and a multi-chip module substrate for interconnecting the LSI chips.

[Conventional technology]

U.S. Patent No. 4,302,625 and application of high-density mounting technology and high-density multilayer substrate (Science Forum, March 15, 1988) as a conventional example of a module board configuration that interconnects multiple LSI chips (also simply called chips) , pages 196 to 197).

In this conventional example, an inspection/technical change pad is provided on the chip mounting surface (hereinafter referred to as the substrate surface) in a multilayer ceramic substrate for LSI chip interconnection.

It has a configuration in which input/output and power supply pins are placed on the back surface of the chip mounting board (hereinafter referred to as the back surface of the mounting board). Furthermore, the configuration is such that a cooling body for dissipating heat from the chip can be thermally connected to the back surface of the chip.

[Problem that the invention seeks to solve]

In the above conventional mounting configuration, the pad for inspection and technology change is LS.
Approximately the same number of chip signal terminals are arranged on the board surface around the I chip, so when mounting LSI chips, which tend to have more terminals, it is necessary to sacrifice chip mounting density in order to secure pad area for inspection and technology changes. I had to.

Furthermore, during module testing, in order to connect the testing probe to the testing/technology change pad, it was necessary to remove the cooling body that should be thermally connected to the back surface of the chip. Instead, a special test cooling system had to be provided that would not interfere with the test probe.

The purpose of the present invention is to meet the above-mentioned (1) reduction in chip mounting density to secure pad areas for inspection and technology changes, and (2) requirements for a cooling system during inspection during module inspection.
The aim is to solve one problem.

In other words, the first object of the present invention is to enable LSI chips to be mounted at high density and to easily test the module without requiring a special chip cooling system during module testing, with the cooling system as it is in actual use. A second object of the present invention is to provide a multi-chip module, and a second object is to provide a module substrate suitable for use with the multi-chip module.

[Means for solving problems]

The above object is achieved by providing a pad for inspection and technology change [and input/output pins (terminals)] on the back surface of the substrate, and a power supply bus (power supply terminal) on the surface of the substrate.

Features of the multi-chip module of the present invention will be listed below and explained in more detail.

(1) A multilayer wiring board having a signal input/output terminal, a power supply terminal, and a pallet for inspection and technology changes, and a plurality of semiconductor L mounted on the board and provided with a cooling means on the back side thereof.
In a multi-chip module consisting of an SI chip, on the surface of the multilayer wiring board, a semiconductor LSI chip according to III, which is provided with a cooling means on its back surface, is electrically connected through an element connection portion, and the peripheral edge thereof is A power supply terminal is arranged through a power supply connection part, and an input/output terminal connected to the semiconductor LSI chip and a pad pattern for inspection and technology change are arranged on the back side of the multilayer wiring board. It is characterized by

(2) The above-mentioned inspection/technology change pad has leads connected to each input/output terminal of the corresponding above-mentioned semiconductor LSI chip, and leads that electrically connect adjacent LSI chips to the above-mentioned multilayer wiring. It is characterized by being connected via a board.

(3) A pad pattern for inspection and technology change is provided on the main surface of the back side of the multilayer wiring board, and a group of input/output terminals are arranged on the periphery of the pad pattern.

Next, the features of the multi-chip module substrate of the present invention will be listed and explained in more detail.

(1) A power supply terminal is provided on the periphery of the semiconductor LSI chip mounting surface where the LSI chip is mounted, and a pad pattern for inspection and technology change and an input/output terminal are provided on the LSI chip mounting surface and the S surface. It is characterized by comprising a multilayer wiring structure including leads from the electrodes of the LSI chips connected to the pad patterns for inspection and technology changes and leads electrically connecting the adjacent LSI chips. shall be.

(2) The inspection and technology change pads are connected to leads that connect to each input terminal of the corresponding semiconductor LSI chip and leads that electrically connect adjacent LSI chips. shall be.

(3) An input/output group is provided at the periphery of the pad pattern for inspection and technology change.

(4) The multilayer wiring structure is characterized in that at least three layers, a power supply layer, a signal input/output layer, and a ground layer are laminated.

(5) The multilayer wiring structure is characterized in that it is composed of a ceramic laminate plate provided with a wiring pattern.

(Function) First, consider placing the pads for inspection and technology changes that were provided around the LSI chip on the front surface of the board on the back side of the board, and instead providing a power bus (power supply terminal) around the chip on the front surface of the board. In the invention, even if the thickness of the conductor used in the power supply bus is reduced to several millimeters or less, there is no limit to its height, so the conductor height can be ensured sufficiently high and the resistance of the power supply path can be kept low. On the other hand, if the pads for inspection and technology changes are placed on the back side of the board rather than the front surface of the board, there will be more room for the chip mounting area, and more pads for inspection and technology changes can be placed. While ensuring a sufficient number of pads.

It becomes possible to mount LSI chips with high density. Additionally, during module inspection, the inspection probe can be connected to the inspection/technology change pad from the back side of the board, and there is no need to remove the cooling body that is thermally connected to the back of the element, so there is no need for a special cooling system during inspection. becomes.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

Fig. 1 is a sectional view of a multi-chip module showing an embodiment of the present invention, and Fig. 2 is a perspective view thereof.
In the figure, 10 is an LSI chip to be mounted, 20 is a cooling body for cooling the chip 10, and 21 is a cooling body 20.
40 is a power supply bus for supplying power to the chip 10, 41 is a power supply return body for applying different voltages of the power supply bus 40, 42 is an insulating layer for insulating the power supply conductors 41 from each other,
30 is a module board, 33 is an element connection part for connecting the chip 10 to the module board 30, 34 is a power supply connection part for connecting the power supply conductor 41 to the module board 30, and 31 is for supply '6 to the chip 10. power supply layer; 32 is a wiring layer that interconnects the chips 10; 5° is a module board 3;
0, 51 is a through conductor for guiding line 1 of the chip 10 to the inspection/technical change pad 50, 52 is a through conductor for connecting the inspection/technical change pad 50 and the wiring layer 32. 35 is an input/output pin for signal connection with other modules or the outside, 60 is an inspection/output pin.
As can be seen from FIGS. 1 and 2, by arranging the pad 50 for inspection and technology change on the back surface of the substrate, the area around the chip 10 has been improved. Chip 10 compared to when it was placed in
can be arranged at a high density of 40 to 50%. Furthermore, during inspection, the inspection probe can be connected from the back side of the board, allowing inspection to be performed in a single assembled module state. Therefore, there is no need to prepare a special cooling system during inspection. Furthermore, the planar arrangement of the inspection/technology change pad 50 has the advantage that the inspection probe can be easily positioned. This means that technology change wiring 6
It also makes it easy to connect 0.

In addition, in this embodiment, in order to arrange the pad 50 for inspection and technology change on the back side of the board, the input/output pins 35 are placed around the module board 30, and the power supply system is placed on the surface of the board as a power bus 40. ing.

〔Effect of the invention〕

According to the present invention, it is possible to improve the LSI chip mounting density while securing a pad area for inspection and technology changes, and it is possible to improve module functions such as increasing calculation speed.

Further, during module inspection, a special inspection cooling system is not required, and the inspection process can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a multi-chip module according to an embodiment of the present invention, and FIG. 2 is a perspective view thereof. In fig. 10... LSI chip 20... Cooling body 30... Module board 40... Power bus 50... Inspection/technology change pad 35... Input/output pin 60... Technology change wiring agent Patent attorney Junnosuke Nakamura

Claims (8)

[Claims] 1. a multilayer wiring board having a signal input/output terminal, a power supply terminal, and a pad for inspection/technical change;
and a plurality of semiconductor LSs each having a cooling means on its back surface.
In a multi-chip module consisting of an I-chip,
On the surface of the multilayer wiring board, the semiconductor LSI chip, which is provided with a cooling means on the back side thereof, is electrically connected through an element connection part, and at the periphery thereof, a power supply terminal is provided through a power supply connection part. A multi-chip module characterized in that input/output terminals connected to the semiconductor LSI chip and pad patterns for inspection and technology changes are arranged on the back surface of the multilayer wiring board. 2. In the above-mentioned inspection/technology change pad, leads connecting to each input/output terminal of the corresponding semiconductor LSI chip and leads electrically connecting adjacent LSI chips are connected via the multilayer wiring board. A multi-chip module according to claim 1, characterized in that: 3. Claim 1, characterized in that a pad pattern for inspection and technology change is provided on the main surface of the back side of the multilayer wiring board, and a group of input/output terminals are arranged on the periphery of the pad pattern.
The multi-chip module according to item 1 or 2. 4. A power supply terminal is provided at the periphery of the semiconductor LSI chip mounting surface where the LSI chip is arranged, and a pad pattern for inspection and technology change and an input/output terminal are provided on the back surface where the LSI chip is mounted, and at least the pad pattern for inspection and technology change is provided. 1. A multi-chip module substrate comprising a multilayer wiring structure including leads from electrodes of the LSI chips connected to the pattern and leads electrically connecting adjacent LSI chips. 5. A patent characterized in that the inspection/technology change pads are connected to leads that connect to each input terminal of the corresponding semiconductor LSI chip and leads that electrically connect adjacent LSI chips. A multi-chip module substrate according to claim 4. 6. Claim 4, characterized in that a group of input/output terminals is provided at the periphery of the pad pattern for inspection and technology change.
The multi-chip module substrate according to item 5 or item 5. 7. The multi-chip according to claim 4, 5 or 6, wherein the multilayer wiring structure is formed by laminating at least three layers: a power supply layer, a signal input/output layer, and a ground layer. Module board. 8. 8. The multi-chip module substrate according to claim 7, wherein said multilayer wiring structure is made of a ceramic laminate plate provided with a wiring pattern.