JPS6213817B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a manufacturing method for mounting an integrated circuit board on a ceramic substrate using a flip-chip method.

Conventionally, this type of manufacturing method is shown in Figures 1 A to F.
I found the one shown here. In the figure, 1 is an integrated circuit board, 2 is an electrode on the integrated circuit board side, 3 is an insulating film, and 4 is an integrated circuit board.
is a conductive material such as Cr-Cu for applying a potential to the integrated circuit board side during electroplating, 5 is an insulator for selectively plating the electrode part, 7 is a solder bump, and 6 is solder and a conductive material 4 is a metal such as Cu to strengthen the connection, 8 is a ceramic substrate, and 9 is an electrode of the ceramic substrate.

Next, the manufacturing process will be explained.

Step (A) As shown in Figure 1A, on the integrated circuit board 1
An electrode 2 made of Al or the like is formed, and a portion other than the electrode 2 is masked with an insulating film 3.

Step (B) As shown in FIG. 1B, a conductive material 4 such as Cr--Cu is deposited on the entire surface.

Step (C) Parts other than the electrode part 2 are masked with an insulator 5, a potential is applied to the conductive substance 4, and a metal 6 such as Cu and a solder bump 7 are formed by electroplating as shown in FIG. 1C. .

Step (D) The insulator 5 and the conductive material 4 are etched using an etching solution as shown in FIG. 1D.

Step (E) By heating, the solder bumps 7 are melted and shaped as shown in FIG. 1E.

Step (F) Solder bumps 7 are melted and integrated circuit board 1 and ceramic substrate 8 are joined as shown in FIG. 1F.

Since the conventional manufacturing method is configured as described above, as shown in FIG. 1F, the solder bump 7 spreads laterally and the height h becomes smaller. Therefore,
When the temperature of the integrated circuit board increases during operation of the integrated circuit, the elasticity of the solder bumps 7 cannot absorb the lateral stress caused by the difference in coefficient of thermal expansion between the integrated circuit board 1 and the ceramic board 8. However, there were drawbacks such as bumps peeling off at the periphery of the integrated circuit board.

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional ones, and the solder bumps are designed so that the elasticity of the solder bumps 7 can absorb the lateral stress generated as a result of the heat generation of the integrated circuit. It is an object of the present invention to provide a manufacturing method for forming an elongate shape.

An embodiment of the present invention will be described below with reference to the drawings. In Fig. 2 a to e, 1 is an integrated circuit board, 2
is an electrode on the integrated circuit board side, 3 is an insulating film, and 4 is an electrode for applying a potential to the integrated circuit board side during electroplating.
A conductive material such as Cr-Cu, 5 an insulator for selectively plating the electrode 2, 7 a solder bump, and 6 a metal such as Cu to strengthen the connection between the solder and the conductive material 4. , 8 is a ceramic substrate, 9
is the electrode on the ceramic substrate side.

Next, the manufacturing process of the present invention will be explained.

Step (a) As shown in FIG. 2a, an electrode 2 is formed on an integrated circuit substrate 1, and a portion other than the electrode 2 is masked with an insulating film 3.

Step (b) As shown in FIG. 2b, a conductive material 4 such as Cr--Cu is deposited on the entire surface.

Step (c) A thick insulator 5 (for example, about 50 μm) is formed to mask the area other than the electrode 2, a potential is applied to the conductive material 4, and a metal such as Cu is formed by electroplating as shown in FIG. 2c. 6 and solder bumps 7 are formed.

Step (d) Solder bumps 7 are melted to connect integrated circuit board 1 and ceramic substrate 8 as shown in FIG. 1d.

Step (e): The insulator 5 and the conductive material 4 are etched using an etching solution as shown in FIG. 2e. In addition,
In the above embodiment, a manufacturing method for a solder bump formation process by electroplating was shown, but in the solder bump formation process by vapor deposition, the conductor 4 for electroplating, which is formed on the entire surface, is not required, so the insulator 5 shrinks. If it has properties, the insulator 5 may be left as is without being removed after the integrated circuit board 1 and the ceramic substrate 8 are bonded.

As described above, according to the present invention, the height h of the solder bumps 7 can be increased, so that heat generation during operation of the integrated circuit is caused. The stress between the integrated circuit board and the ceramic board can be absorbed by the elasticity of the solder bumps 7.

[Brief explanation of the drawing]

FIGS. 1A to 1F are cross-sectional views for explaining a conventional method of manufacturing a flip-chip mounting structure, and FIG.
-e are cross-sectional views for explaining a method of manufacturing a flip-chip mounting structure according to an embodiment of the present invention. 1 is an integrated circuit board, 2 is an electrode, 3 is an insulating film, 4
5 is a conductive material, 5 is an insulator, 6 is a metal, 7 is a solder bump, 8 is a ceramic substrate, and 9 is an electrode. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A conductive material is uniformly formed on the entire surface of an integrated circuit board, a thick insulator is formed to mask areas other than the electrode parts provided on the board, and the electrode parts are covered with electroplating. A method for manufacturing a flip-chip mounting structure, which comprises forming solder bumps, connecting electrodes on the integrated circuit board side and electrodes on the ceramic substrate side by melting the solder bumps, and then removing the insulator and conductive substance. 2. Form a thick insulator to mask areas other than the electrodes provided on the integrated circuit board, form solder bumps on the electrodes by vapor deposition, etc., and melt the solder between the electrodes on the integrated circuit board side and the electrodes on the ceramic substrate side. 1. A method for manufacturing a flip-chip mounting structure, which comprises removing the insulator after the connection is made.