JPS59231841A - Semiconductor device - Google Patents

Abstract

PURPOSE:To unify the heat dissipating quantities of chips according to the mounting positions on a substrate by a method wherein walls for conduction paths of heat to a radiator are provided protruding between the mutual semiconductor chips of the whole from the upper inside face of a cap. CONSTITUTION:A radiator 9 is adhered 10 on a cap 7A to seal airtightly semiconductor chips 2 of the plural number of pieces equipped on a substrate 1, walls 12 to protrude between the mutual chips 2 of the whole from the upper inside face of the cap 7A are provided, and adhered 8, 13 to the substrate 1 to seal airtightly. At this time, because heat flows flowed out from the surfaces of the chips 2 are transmitted through the adhesives 8, 13, the differences of the heat transmitting distances and the heat transmitting sectional areas according to the mounting places (a), (b), (c) are reduced, heat resistances between the chips are unified, and heat resistance as the whole is also reduced. Moreover because the walls 12 are formed in one body structure with the cap, no bad influence is applied to sealing work.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a semiconductor device having a structure in which a plurality of semiconductor chips are mounted on a substrate and has a cap for hermetically sealing these semiconductor chips. This invention relates to an improvement that reduces non-uniformity in the amount of heat dissipation depending on the mounting position on the board.

[Prior art]

Figure 1 is a vertical cross-sectional view showing an example of a conventional device of this type;
The figure is a sectional view taken along the line 2 in FIG. 1.

Note that FIG. 1 corresponds to a cross-sectional view taken along line I--I in FIG. 2.

In the figure, (1) is a substrate, (2) is a flip-chip semiconductor chip mounted on the substrate i11, and (3)
is for engineering change (rad, (4)
is a bottle for external connection, (5) is a metal plate with good thermal conductivity, (
6) is an adhesive with good thermal conductivity that bonds the metal plate (5) to the top surface of the semiconductor chip (2), (7) is a cap for airtight sealing, and (8) is a cap that connects the cap (7) to the substrate. Adhesive with good thermal conductivity that adheres to fil, (9) is a heat sink,
Qo+ is an adhesive with good thermal conductivity that adheres the heat sink (9) to the top surface of the cap (7), (Ill is the cap (
7) is a gas with good thermal conductivity that fills the voids within.

In a semiconductor device configured in this way, a semiconductor chip (
The heat generated in step 2) passes through the adhesive (6) and metal plate (5) from the back of the tap, and is transmitted to the gas (U) + cap (7), adhesive (10+), and heat sink (9), and is released into the external air. What is emitted into the inside and what is emitted from the chip surface to the substrate (
1).

Some is dissipated into the outside air via the adhesive (8), the cap (7), the adhesive (10), and the heat sink (9). The adhesive (6) and metal plate (5) in the heat transfer path escaping from the back surface of the semiconductor chip (2゛1) are made of materials with good thermal conductivity, and the contact thermal resistance is almost 7.
Poi.

Further, since the gap between the metal plate (5) and the cap (7) is extremely small and a gas surrounding with good thermal conductivity is filled in this gap, the thermal resistance is sufficiently small. Furthermore, a cap (7),
The adhesive (101) and the heat sink (9) are both made of materials with good thermal conductivity, and the contact between the adhesive (101) and the cap (7) and the heat sink (9) is extremely good. Thermal resistance is also extremely low.

As mentioned above, heat conduction from the long surface of the semiconductor napkin (21) is extremely effective; For example, if the semiconductor chip (21) is mounted as shown in Fig. 2, the semiconductor chips (2i) in Fig. ) The heat generated at &(1
The heat transfer distance cape and heat transfer cross-sectional area of the casing that passes through j and reaches the contact area between the cap (7) and the board (li) is A.Therefore, the position G of 8 is the position of the mounted Nisso and b. There is a difference in thermal resistance between the chip mounted in the Amatake position and the chip incorrectly installed in the C position, and the thermal resistance of the chip mounted in the C position becomes particularly large, causing variations in thermal resistance between chips. There were some drawbacks.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones as described above, and a new heat transfer path is provided between the mounted semiconductor chips by bonding the cap and the substrate in the same way as the periphery of the substrate. This provides a semiconductor device that enables uniform heat conduction to each chip and eliminates variations in thermal resistance between chips.

[Embodiments of the invention]

FIG. 3 is a longitudinal cross-sectional view showing an embodiment of the present invention, and FIG. 4 is a cross-sectional view of the 1S-LV strain of FIG. Note that FIG. 3 corresponds to a cross-sectional view taken along the line III--III in FIG. 4. In the figure, the same reference numerals as in the conventional example shown in Figures 1 and 2 indicate equivalent parts. (7A) is a cap that airtightly seals the semiconductor chip (2), and (12) is a wall that was installed in the first place (7 people) in order to obtain uniform heat transfer between the chips. This wall (121) is attached to the base plate (11) with an adhesive (13) with good thermal conductivity.The adhesive (13) is the same as the adhesive (Sj) to facilitate the process. It is desirable to use

In FIG. 4, α4) is a conducting wire that has undergone engineering changes.

If the structure is as shown in this example, the semiconductor chip (2
) is not only conducted to the cap ('7A) through the adhesive (8), but also through the adhesive Oal
Heat is also transferred through As a result, the differences in heat transfer distance and heat transfer cross section between the mounting locations a, b, and C of the semiconductor chip (2) shown in FIG. This also reduces the overall thermal resistance.

In addition, as shown in Figure 4, the wall (electricity) for heat transfer is not connected to the peripheral part of the cap (7A), and the wall (I
2) Since they are not connected to each other, there is no problem when making engineering changes.

Furthermore, since the wall (12) is integrated with the cap (7A), even if the number of chips increases, the number of sealing steps does not increase, and the chips can be sealed all at once.

In the above embodiment, the case where nine chips are mounted is shown, but there is no limit to the number of chips, and the same effect can be obtained no matter how many chips are mounted. In addition, the seed opening provided to obtain uniform heat conduction between the chips in Fig. 4 is the 5th one.
Wall (12A) in another embodiment whose plan sectional view is shown in the figure
The same effect can be obtained even if it is provided to surround the periphery of the chip.

Further, it is also possible to connect all the walls (12B) in still another embodiment, which does not require engineering changes and is shown in a cross-sectional plan view in FIG.

〔Effect of the invention〕

As explained above, in the semiconductor device of the present invention, a heat dissipation device is provided on the cap that hermetically seals a plurality of semiconductor chips mounted on a substrate, and all the semiconductor chips are disposed from the upper surface of the cap. Since a protruding wall is provided between the two, uniform heat dissipation is possible regardless of where the semiconductor chip is mounted. Furthermore, since the wall is integrally constructed with the cap, it does not have any adverse effect on the sealing operation.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view showing an example of a conventional device, and Fig. 2 is a longitudinal sectional view showing an example of a conventional device.
3 is a longitudinal sectional view showing an embodiment of the present invention, FIG. 4 is a sectional plan view taken along line IV-IV in FIG. 3, and FIG. FIG. 6 is a plan sectional view of still another embodiment of the present invention. In the figure, (1) is a substrate, (2) is a semiconductor chip, (
"A) + (7B), ('70) is the cap, (8)
is adhesive, (9) is a heat sink (heat dissipation device), (10
) is the adhesive, and (121, (12A) + (12B) is the wall. The same reference numerals in the figures indicate the same or corresponding parts. Agent Masuo Oiwa Figure 1 Figure 2 Figure 31'A 4 figure

Claims (3)

[Claims] (1) A cap attached to a substrate on which a plurality of semiconductor chips are mounted so as to hermetically seal the semiconductor chips; and a heat dissipation device for dissipating the heat to the outside, - a wall protruding from the upper surface of the cap between all the semiconductor chips and forming a conduction path for the heat to the heat dissipation device; A semiconductor device fn characterized by the following. (2) The semiconductor device according to claim 1, wherein the wall is formed so as to surround the west side of each semiconductor chip without being connected to the inner side of the cap. (3) The wall is connected to the inner surface of the cap and is configured to divide the inside of the cap into a grid, and each of the grids accommodates four semiconductor chips. The semiconductor device according to item 1.