JPH1140740A - Multi-chip module and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow signal input/output terminals and supply voltage supplying electrodes to be provided from the side of a base board, in order to minimize the lengths of leads when a multi-chip module is incorporated into a mother board or the like. SOLUTION: Such a groove as to put a portion of a base board (1) in relief so as to be an island is formed at a position where an electrode is formed in the base board. Then, insulating films 5 and 6 are formed so as to embed a bare chip 3 or a like that is mounted on the substrate, after which the base board is thinned while etched or ground from its reverse surface, thereby forming an island conductive portion isolated by the films 5 and 6. As a result, electrodes that are electrically isolated from a grounding conductor are formed on the reverse surface of the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a structure of a multi-chip module and a method for manufacturing the same.

[0002]

2. Description of the Related Art As one means for reducing the size and improving the performance of electronic devices, there is a so-called multi-chip module in which a plurality of bare semiconductor chips and passive elements are connected to each other to form one module.

As an example of a conventional method for mounting a bare semiconductor chip, as shown in Japanese Patent Application Laid-Open No. 3-155144, an insulating film having a predetermined thickness larger than the thickness of the bare semiconductor IC chip is previously determined by a predetermined distance from the outer shape of the bare semiconductor IC chip. A large hole is formed, the insulating film is bonded to a support plate with an adhesive, and the bare semiconductor IC chip is bonded to the hole of the bonded insulating film with an adhesive, and is insulated from the bare semiconductor IC chip. Film gaps and bare semiconductor ICs
The surface of the chip is coated with a liquid resin of the same type as the insulating film so that the height of the insulating film layer and the insulating film are uniform, then heat-cured, and the resin on the conductor pad portion on the bare semiconductor IC chip is removed by photolithography. After the removal, a conductor film is formed on the entire surface, and a predetermined conductor wiring is formed by photolithography.

An example of a conventional semiconductor device (particularly a multi-chip module) and a method of manufacturing the same are disclosed in Japanese Patent Laid-Open No. 5-47856.
As shown in the number, at least one
A chip is mounted on each of the stages, an insulating film is applied to the package and the chip, and a via hole is formed in the insulating film to connect the connection pad on the package and the pad on the chip. It is configured to be connected by a wiring pattern.

[0005]

Problems to be Solved by the Invention
In JP-A-5-47856 and JP-A-5-47856, a support plate or a package is an insulating substrate. Generally, the material of the insulating substrate has a heat conductivity lower by one order or more than that of a conductive material and a semiconductor material, and thus the power consumption is large. It is not suitable for mounting an amplifier or the like.

[0006] Further, in the embodiment of JP-A-5-47856,
There is no electrical connection between the mounting conductor layer (e.g., Au-Si eutectic or conductive adhesive) on the back surface of the chip and the conductor wiring on the insulating film, and the circuit operation lacks stability in a high frequency region.

Further, in an example of a conventional method for mounting a bare semiconductor chip disclosed in Japanese Patent Application Laid-Open No. 3-155144, a bare semiconductor I
Air gap between C chip and insulating film and bare semiconductor IC
After applying the surface of the chip with the same kind of liquid resin as the insulating film so that the height of the insulating film layer and the insulating film layer are uniform, in the step of thermosetting, the bare semiconductor IC chip and the insulating film are shrunk by the liquid resin during thermosetting. Depressions are likely to occur in the gaps between them. When a dent is formed in the gap, a defect such as a short circuit or disconnection occurs in the conductor wiring in the gap.

Further, in an example of a semiconductor device disclosed in Japanese Patent Application Laid-Open No. 5-47856 and a method of manufacturing the same, in a thermosetting step of a liquid resin, insulation of a gap between a package and a chip is caused by contraction of the liquid resin during thermosetting. The film is likely to be dented, and the wiring pattern in the void is likely to be defective such as short circuit or disconnection.

Further, the conventional example does not have a structure in which a cap can be mounted in a multichip module unit. For this reason, there is no mechanical protection against damage from the outside, and it is easily broken. Further, in the case of operating in a high frequency range, there is a problem that the electromagnetic shield is weakened and is easily susceptible to interference from others.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a planar chip made of a metal or a semiconductor on which a bare chip component such as a semiconductor element or an IC chip and a metallic conductive block are mounted. It comprises a base substrate, a bare chip component comprising a plurality of semiconductor elements or IC chips having metal bumps on electrodes mounted thereon, and a resin-like first insulating film covered so as to embed the bare chip component. The insulating film and the bump on the bare chip are flattened to a predetermined height, and a multilayer wiring pattern is formed thereon by a metal layer and an insulating film, and the bump and a part of the pattern are formed. In a multichip module that is electrically connected, a part of a conductor on the insulating film and the base substrate are connected by a conductive block or through hole. At a predetermined position, a groove is formed so that a part of the base substrate protrudes in an island shape, and an insulating film is formed so as to embed the bare chip component and the metallic conductive block. Then, the base substrate is etched or ground from the back surface. By forming an island-shaped conductor portion separated by the insulating film, an electrode electrically isolated from the ground conductor can be formed on the back surface of the base substrate.

[0011] In addition, a portion of the side opposite to the surface on which the bare chip component is mounted, which is to be a side surface of the unit module when cut out into a unit module size, has a shaving beforehand when the depth is reduced by the etching or polishing. After forming a concave portion deeper than the margin, after etching or grinding, cut out into a unit module size, and provide a metal cap having a reverse concave so as to fit into the concave portion formed on the side surface of the module.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 is a sectional view of a multichip module according to an embodiment of the present invention. In FIG. 1, planar base substrates 1-1 and 1-2 made of metal or semiconductor, and adhesive layers 2-1 2-2 and 2-3 for chip mounting are provided thereon, and metal A bare chip component 3 consisting of a plurality of semiconductor elements or IC chips having bumps 4 of a property (for example, Au or Al) and a metallic conductive block 11 are mounted, and the bare chip component 3 and the conductive block 11 are embedded therein. A resin-covered first insulating film 5, a first wiring pattern 8 formed on the first wiring pattern by a metal layer, a capacitor 9 formed on the first wiring pattern, and a second wiring formed on the first wiring pattern by a metal layer It comprises a pattern 10, a third wiring pattern 7 formed of a metal layer with a second insulating film 6 interposed therebetween, and a metal cap 12 covering the whole. In this multi-chip module, electrodes serving as signal input / output terminals and power supply terminals are formed on the back surface of the base substrate and are formed on the conductive block 11.
Is connected to the third wiring pattern 7 formed of a metal layer.

FIG. 2 is a view of the multichip module according to the embodiment of the present invention as viewed from the back. In FIG. 2, a portion 1-1 serving as a ground of the base substrate and a portion 1 serving as an electrode
−2 is electrically isolated by the first insulating film 5. Further, the conductive cap 12 is provided so as to be fitted and stopped in the recess 13 provided on the side surface.

FIG. 3 shows a cross section of the multichip module according to the embodiment of the present invention before the back surface of the base substrate is etched or ground. The base substrate 1 is thinned by etching or grinding from the back surface to the thickness of a groove (indicated by a dotted line in the figure) provided on the opposite side so that a part of the base substrate emerges in an island shape. The electrode part 1-2 and the ground conductor part 1-1 can be separated by the one insulating film 5.

FIG. 4 is another cross section of the multichip module of the present invention, showing a portion where the conductive cap 12 is fixed on the side surface. A portion of the base substrate 1 on the side opposite to the surface on which the bare chip component is mounted, which is to be a side surface of the unit module when cut out into a unit module size, has a depth of shaving when previously thinning by etching or polishing. A deep recess 13 was provided, the layer was thinned by the above-mentioned etching or grinding to the point indicated by the dotted line in the figure, cut out to a unit module size, and then had a reverse recess so as to fit into the recess 13. FIG. 3 is a view in which a metal cap 12 is provided.

FIG. 5 is a cross-sectional view of the multi-chip module of the present invention, showing a case where the multi-chip module is cut along a dotted line for thinning shown in FIGS. The base substrate 1 is separated by a first insulating film 5 into a portion 1-1 serving as a ground conductor and a portion 1-2 serving as an electrode. The concave portion 13 for stopping the cap is provided.

[0017]

According to the present invention, a plurality of bare chip components having metal bumps on electrodes and a metal conductive block are mounted on a planar base substrate, and these are formed into a resin-like first insulating film. And cover the bump, the block, and the insulating film with a predetermined same height,
In addition, it is possible to provide a signal input / output terminal and an electrode for supplying a power supply voltage from the base substrate side in a multi-chip module for forming a multilayer wiring pattern. The line portion can be made as short as possible, and the characteristics in the high frequency range can be greatly improved.

Further, in the present invention, it is possible to form a concave portion on a side surface of the unit module when the multi-chip module is cut into a unit module size, and to provide a conductive cap for covering the entire module using the concave portion. Made it possible. For this reason, mechanical protection is provided against external damage, and when the device is operated in a high-frequency region, the electromagnetic shielding effect is enhanced, and it is possible to reduce the possibility of interference from others.

[Brief description of the drawings]

FIG. 1 is a sectional view of a multichip module according to an embodiment of the present invention.

FIG. 2 is a top view of the back surface of the multichip module according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view of a multi-chip module according to an embodiment of the present invention in the course of manufacturing.

FIG. 4 is a sectional view of another position of the multi-chip module of FIG. 3;

FIG. 5 is a sectional view of another position in the course of manufacturing the multi-chip module of FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base board, 2 ... Adhesive layer, 3 ... Bare chip, 4 ... Bump, 5 ... First insulating film, 6 ... Second insulating film, 7 ... Third
Wiring pattern, 8: first wiring pattern, 9: capacitor, 10: second wiring pattern, 12: cap, 13 ...
Depressed part, 14 ... Unit module.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Osamu Kagaya 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. Inside the Central Research Laboratory

Claims (4)

[Claims] A flat base substrate made of a metal or a semiconductor provided with a metal ground conductor layer, and a plurality of semiconductor elements or a plurality of semiconductor elements having metal bumps on electrodes mounted thereon.
A bare chip component comprising a C chip, and a resin-like first insulating film covering the bare chip component so as to be embedded therein, wherein the insulating film and the bump on the bare chip are flattened to a predetermined same height; In a multi-chip module in which a multilayer wiring pattern is formed by a metal layer and an insulating film on which a bump and a part of the pattern are electrically connected, a part of the conductor on the insulating film and the base The substrate is connected by a conductive block or through-hole, and a portion where the conductive block or through-hole is connected to the base substrate is isolated by another base substrate portion and an insulating film, and a part of the base substrate is in an island shape. A multi-chip module having a structure in which the electrodes are formed. 2. The multi-chip module according to claim 1, wherein a recess is provided on a part of the side surface of the base substrate, and a metal cap is provided to cover the entire multi-chip module so that the recess serves as a stopper. A multi-chip module, characterized in that: 3. A flat base substrate made of a metal or a semiconductor is provided with a groove on one surface thereof so that a part of the base substrate is raised in an island shape, and the groove is formed in the island-shaped portion and other portions on the same surface. A metal bump having a height of at least the unevenness of the bare chip component on each electrode of the bare chip component by mounting a bare chip component and a conductive block including a plurality of semiconductor elements or IC chips using a conductive material. Is provided, and the bare chip component, the bumps, and the blocks are covered with a resin-like first insulating film so as to be embedded therein, and the bumps, the blocks, and the insulating films are flattened to a predetermined same height. A multilayer wiring pattern is formed by a metal layer and an insulating film, and the bumps and the blocks are electrically connected to a part of the pattern. Multichip module fabrication method characterized by comprising the forming an isolated island-like conductive portions by the insulating film as an electrode by thin layer by etching or polishing from the back surface of the scan board. 4. A method for manufacturing a multi-chip module according to claim 3, wherein a predetermined depth is set at a position which becomes a side surface of the module when cut out into a unit module size on a surface opposite to the surface on which the bare chip component is mounted. Is provided with a plurality of recesses deeper than the shaving margin when thinning by etching or polishing, and shallower than the thickness of the base substrate, and after the etching or grinding, cut out into a unit module size, and the side surface of the base substrate A method for manufacturing a multi-chip module, comprising: providing a metal cap that covers the entire multi-chip module so that the recess formed as a stopper functions as a stopper.