JPS6041861B2 - semiconductor equipment - Google Patents

Description

Detailed Description of the Invention The present invention relates to a semiconductor device in which a semiconductor chip (hereinafter abbreviated as a "chip") having a plurality of electrodes is mounted on an insulating substrate for package construction (abbreviated as a "package substrate"). This is related to the improvement of.

Fig. 1A is a perspective view showing an example of the structure of a chip having ■ protruding electrodes, Fig. 1B is Fig. 1A (7) IB-IB
FIG.

In the figure, 1 is a chip made of silicon (Si) and has a plurality of active elements such as transistors formed on its main surface, and 2 is a chip 1 made of gold and provided on the periphery of the main surface of chip 1. m protruding electrodes connected to any one of the plurality of active elements.

In Figure 2A, two chips with m protruding electrodes are bonded face-down (FaceDownBond).
ing) A plan view showing an example of a conventional semiconductor device equipped with a connected package substrate, FIG. 2B is the same as ■B in FIG. 2A.
-■ It is a cross-sectional view along the B line.

In the figure, 1a and lb are first and second chips respectively having the same configuration as the chip 1 shown in FIG. Note that the ■ number of protruding electrodes 2 on the first chip 1a
Of these, seven protruding electrodes 2a1 are each connected to an external lead, and similarly, seven protruding electrodes 2b1 of the second chip lb(7)■ protruding electrodes 2 are each connected to an external lead. The remaining three protruding electrodes 2a2 of the ■ protruding electrodes 2 of the first chip 1 are connected to the remaining three protruding electrodes 2a2 of the corresponding second chip lb(7)m protruding electrodes 2.
The protruding electrodes 2b2 are connected to each other. 3
is a package substrate made of alumina ceramic, 4a is made of a gold film, and is provided on the surface of the package substrate 3,
Seven protruding electrodes 2a1 of the first chip 1a are each connected to one end by face-down bonding, and the other end extends to the peripheral edge of the package substrate 3, and one of the external leads 5a is connected to this end. 7 with the ends glued
Similarly, the first external lead connection film 4b is
seven second external lead connection films in which the seven protruding electrodes 2b1 of the second chip lb are each connected to one end, and one end of the external lead 5b is adhered to the other end;
Reference numeral 4c is made of a gold film, and is provided on the surface of the package substrate 3, and the three protruding electrodes 2a2 of the first chip 1a and the three protruding electrodes 2b2 of the second chip 1b are provided on both ends of the face. 3 connected by down bonding
There are several electrode wiring films.

However, such conventional semiconductor devices have the following drawbacks.

That is, the first drawback is that since the package substrate 3 is made of alumina ceramic made by sintering alumina powder, its surface generally has irregularities and undulations of several PWL.

Due to these irregularities and undulations, a fine pattern width of, for example, about 100 pm or less is formed on the surface of the package substrate 3.
It is not easy to form the first external lead connection film 4a1, the second external lead connection film 4b, and the electrode wiring film 4c, and furthermore, when the number of protruding electrodes 2a1 and 2a2 of the first chip 1a increases, It is also possible to connect these to the first external lead connection film 4a and the electrode wiring film 4c at the same time by face-down bonding.
When the number of layers increases, it is not easy to simultaneously connect them to the second external lead connection film 4b and the electrode wiring film 4c by phase down bonding. Therefore, the number of protruding electrodes 2a1 and 2a2 of the first chip 1a and the protruding electrodes 2b1 and 2b2 of the second chip 1b is limited to 1, and high-density integration of these chips 1a and 1b is made possible. It was not easy to achieve this goal. A second drawback is that the materials of the first chip 1a and the second chip 1b and the material of the package substrate 3 are different. This package board 3 is configured. Since the coefficient of thermal expansion of the alumina ceramic is approximately twice that of Si constituting the first chip 1a and the second chip 1b, the heat generated during operation of these chips 1a and 1b These chips 1a and 1b and the package base. When the temperature of the plate 3 rises, between the protruding electrode 2a1 of the first chip 1a and the first external lead connection film 4a,
and the respective bonding connection parts between the protruding electrode 2a2 and the electrode wiring 4c, between the protruding electrode 2b1 of the second chip 1b and the second external lead connection film 2b1, and between the protruding electrode 2b2 and the electrode wiring film 4c. Thermal strain occurs in each bonding connection between the first chip 1a and the second chip 1b, which destroys the bonding connection and the first chip 1a and the second chip 1b no longer function as semiconductor elements. There was a risk that reliability would decline. The third drawback is that when it is necessary to cross each of the seven first external lead connection films 4a, the seven external lead connection films 4b, or the three electrode wiring films 4c, it is difficult to form them easily. I couldn't do it.

The present invention has been made in view of the above-mentioned drawbacks, and includes a semiconductor substrate made of the same material as that of a semiconductor chip, an insulating film formed on the surface of this semiconductor substrate, and a A wiring board having a wiring film formed corresponding to the electrodes of the semiconductor chip is fixed on the surface of the package substrate, and the semiconductor chip is connected by face-down bonding so that the electrode is directly connected to the wiring film. In particular, it is an object of the present invention to provide a highly reliable semiconductor device in which a highly densely integrated chip is mounted on a package substrate.

FIG. 3A is a plan view showing a semiconductor device according to an embodiment of the present invention, which is equipped with a package substrate on which a wiring board on which two chips having ■ projecting electrodes are mounted;
FIG. 3B is a sectional view taken along the line ■B--■B of FIG. 3A.

In the figure, 1a and 1b are first chips 1a and 1b similar to the first chip 1a and second chip 1b shown in FIG.
and a second chip. 10 is an S1 substrate made of S] similar to the first chip 1a and the second chip 1b;
11 is a Si substrate 1 made of silicon oxide (SiO2), etc.
The insulating film 12a formed on the surface of the first chip 12a is made of a gold film, and is provided on the surface of the insulating film 11, and each of the seven protruding electrodes 2b1 of the first chip 1a is face-down bonded to one end. The seven first electrode lead-out films 12b are connected, and the other end extends to the peripheral edge of the insulating film 11, and the bonding wire is connected to this end.
Similarly, the seven protruding electrodes 2b of the second chip 1b
1 is connected to one end and a bonding wire is connected to the other end. Seven second electrode lead-out films 12c are made of a gold film and are provided on the surface of the insulating film 11, as shown in FIG. These are three electrode wiring films that function similarly to the electrode wiring film 4c shown in FIG.

13 is a Si substrate 10, an insulating film 11, a first electrode lead film 12a1, a second electrode lead film 12b, and an electrode wiring film 1.
This is a wiring board made of 2c.

Reference numeral 14 denotes a package substrate on which the wiring board 13 is fixed; 15a is made of a gold film; the periphery on the surface of the package substrate 14 corresponds to each of the seven first electrode lead-out films 12a of the wiring board 13; Similarly, the seven first external lead connection films 15b formed to correspond to the seven second electrode lead-out films 12b of the wiring board 13 are The second external lead connection film 16a is seven bonding wires 16b that respectively connect the seven first electrode extraction films 12a and one end of the seven first external lead connection films 15a. 17a and 17b are seven bonding wires connecting the second electrode extraction film 12b and one end of the second external lead connection film 15b, respectively, and 17a and 17b are the seven first external lead connection films 15a and 17b, respectively. There are seven first and second external leads, each of which has one end bonded to the other end of the seven second external lead connection films 15b.

In the semiconductor device of this embodiment configured in this way, the surface of the S1 substrate 10 constituting the wiring board 13 can be made extremely flat by etching, polishing, etc. The surface of the insulating film 11 also becomes flat.

Therefore, it becomes possible to easily form the first electrode lead-out film 12a, the second electrode lead-out film 12b, and the electrode wiring film 12c with a fine pattern width of about several μm on the surface of the insulating film 11. , the protruding electrode 2a of the first chip 1a
Even if the number of chips 1 and 2a2 increases, it is possible to simultaneously connect them to the first electrode lead-out film 12a and the electrode wiring film 12c by face-down bonding. Even if the number of protruding electrodes 2b1 and 2b2 increases, they are connected to the second electrode lead-out film 12b and the electrode wiring film 12, respectively.
It becomes possible to simultaneously connect face-down bonding to C. Therefore, as in the conventional example shown in Fig. 2,
The number of protruding electrodes 2a1 and 2a2 of the first chip 1a and the protruding electrodes 2b1 and 2b2 of the second chip 1b is not limited, and these chips 1a
and 1b can be integrated at high density. Also,
Since the material of the S1 substrate 10 constituting the wiring board 13 and the material of the first chip 1a and the second chip 1b are the same, the heat generated during operation of these chips 1a and 1b causes these chips to be damaged. Even if the temperatures of 1a and 1b and the wiring board 13 rise, the difference between the protruding electrodes 2a1 of the first chip 1a and the first electrode lead-out film 12a, and between the protruding electrodes 2a2 and the electrode wiring film 12c, respectively. Thermal strain occurs in the bonding connections between the protruding electrodes 2b1 and the second electrode lead-out film 12b of the second chip 1b, and between the protruding electrodes 2b2 and the electrode wiring film 12c. Never. Therefore, as in the conventional example shown in FIG. 2, these bonding connections are destroyed by this thermal strain, and the first chip 1a and the second chip 1b no longer function as semiconductor elements. Therefore, reliability can be improved. Furthermore, since a multilayer wiring film can be easily formed on the surface of the insulating film 11 of the wiring board 13, the seven first
Even if it is necessary to intersect each of the seven electrode lead-out films 12a and the three electrode wiring films 12c, these can be easily formed. In this embodiment, the wiring board 13 is directly fixed on the surface of the package board 14, but if necessary, the wiring board 13
A metal plate, such as molybdenum, having a coefficient of thermal expansion close to that of the S1 substrate 10 constituting the wiring board 13 may be interposed between the S1 substrate 10 and the package substrate 14 .

In this case, thermal strain caused by the difference between the coefficient of expansion of the Si substrate 10 and that of the package substrate/board 14 can be absorbed by the metal plate. Further, in this embodiment, the first chip 1a, the second chip 1b and the wiring board 13
Although both of the S1 substrates 10 are made of Si, they are not necessarily limited to Si, and both may be made of other semiconductor materials such as gallium arsenide. Further, in this embodiment, the case where two chips, the first chip 1a and the second chip 1b, are connected to the wiring board 13 by face-down bonding is described as an example, but the present invention is not limited to this. , three or more chips may be connected to the wiring board by face-down bonding. As described above, in the semiconductor device of the present invention, a wiring board using a semiconductor substrate made of the same material as the semiconductor chip is fixed on the surface of the package substrate, and a wiring board formed on the surface of the semiconductor substrate is fixed. A wiring film corresponding to the electrodes of the semiconductor chip is formed on the insulating film, and the semiconductor chip is face-down bonded so that the electrodes are directly connected to the wiring film, so that the following effects can be obtained.

That is, since the surface of the semiconductor substrate can be made extremely flat, the surface of the insulating film formed on the surface of the semiconductor substrate also becomes flat. Therefore, it is possible to miniaturize the pattern width of the wiring film formed on the insulating film, and even if the number of electrodes on the semiconductor chip increases, it is possible to simultaneously connect these electrodes face-down to the wiring film. Since bonding connection becomes possible, high-density integration of the semiconductor chips can be achieved. Also,
Since the semiconductor chip and the semiconductor substrate are made of the same semiconductor material, even if the temperature of the semiconductor chip and the wiring board rises due to heat generated during operation of the semiconductor chip, the semiconductor No thermal strain occurs at the connection portion between the electrode of the chip and the wiring or wire film. Therefore, unlike the conventional example, the connection portion is not destroyed by this thermal strain and the chip does not function as a semiconductor element, and reliability can be improved. Furthermore, since a multilayer wiring film can be easily formed on the surface of the above-mentioned insulating film of the above-mentioned semiconductor substrate, a crossing wiring film can be easily formed.

[Brief explanation of drawings]

FIG. 1A is a perspective view showing an example of the structure of a chip having one bar of protruding electrodes, FIG. 1B is a sectional view taken along the line 1B-1B of FIG. 1A (7), and FIG. 2A is 1C@ FIG. 2B is a plan view showing an example of a conventional semiconductor device equipped with a package substrate in which two chips having protruding electrodes are connected by face-down bonding. A cross-sectional view of
FIG. 3A is a plan view showing a semiconductor device according to an embodiment of the present invention, which is equipped with a package substrate on which a wiring board on which two chips having ■ projecting electrodes are mounted;
FIG. 3B is a cross-sectional view taken along line 2B--B in FIG. 3A.

Claims (1)

[Claims] 1. A semiconductor chip having a plurality of electrodes on its main surface, a semiconductor substrate made of the same material as this semiconductor chip, an insulating film formed on the surface of this semiconductor substrate, and the above semiconductor chip on the surface of this insulating film. and a wiring film formed corresponding to each of the plurality of electrodes, and the semiconductor chip is connected by face-down bonding so that the electrode is directly connected to the wiring film, and the wiring board is A semiconductor device having an insulating substrate for package construction fixed on its surface.