JP2001156247A - Semiconductor device - Google Patents

Abstract

(57) Abstract: A semiconductor that can sufficiently radiate heat even in a semiconductor chip sandwiched between semiconductor chips at the top and bottom, and that can sufficiently radiate heat even in semiconductor chips positioned above and below. Provided is a semiconductor device in which positioning between chips is easy. SOLUTION: A semiconductor chip 12 having a through hole on the surface.
A, 12B, and 12C, a positioning pin 15 that can be inserted into the through hole 16, and a heat sink 14 that is in close contact with the upper surface 18 of the semiconductor chip 12A. When the semiconductor device 10 is configured in this manner, the heat generated in the semiconductor chip 12B can be transferred to the heat radiating plate 14 via the positioning pins 15, so that the semiconductor chip 12B sandwiched between the upper and lower semiconductor chips 12 can be transferred. Heat does not accumulate in
Thus, the temperature rise of the semiconductor chip 12 is suppressed, and stable operation can be ensured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a plurality of semiconductor chips are stacked, and more particularly to a semiconductor device in which the operation is stabilized by taking measures against heat radiation.

[0002]

2. Description of the Related Art Heretofore, there has been known a semiconductor device in which a plurality of semiconductor chips are incorporated in a single package to achieve further multi-functionality and high-density mounting. Multi-chip package).

[0003] Various types of MCPs have been proposed. For example, a plurality of semiconductor chips are prepared, and these semiconductor chips are stacked. By stacking the semiconductor chips in this way, it is possible to easily connect the electrodes formed on the surface of the semiconductor chip without increasing the mounting area.

[0004]

However, the above-described semiconductor device has the following problems.

That is, when the semiconductor chip constituting the semiconductor device operates, the chip body generates heat. In the semiconductor device, the semiconductor chip sandwiched between the upper and lower semiconductor chips is
Since the area exposed to the atmosphere is small, heat is not sufficiently radiated. Therefore, there is a possibility that a malfunction of a semiconductor chip or a semiconductor device may occur due to an increase in resistance value due to heat generation.

[0006] In addition, even if the semiconductor chips positioned above and below the semiconductor device are not sufficiently exposed to the atmosphere, the amount of heat dissipation may not be able to keep up with the amount of heat generated when the semiconductor chip operates at a high clock rate. there were.

Further, when stacking semiconductor chips, electrodes formed on the front and back surfaces of the semiconductor chip are brought into contact with each other to achieve electrical conduction. However, since these electrodes are fine, accurate positioning is required. Needed equipment.

The present invention pays attention to the above-mentioned conventional problems, and can sufficiently radiate heat even in a semiconductor chip sandwiched between upper and lower semiconductor chips, and can sufficiently radiate heat also in a semiconductor chip positioned above and below. It is another object of the present invention to provide a semiconductor device in which positioning between semiconductor chips to be stacked is easy.

[0009]

According to a first aspect of the present invention, there is provided a semiconductor device comprising: a semiconductor module in which semiconductor chips connectable in a thickness direction are stacked; a heat radiating plate in close contact with a surface of the semiconductor module; The semiconductor device is characterized by having a heat transfer pin penetrating through the semiconductor chip and the heat sink constituting the module. According to the semiconductor device of the first aspect, the heat sink is provided on the surface of the uppermost semiconductor chip. For this reason, the heat generated in the uppermost semiconductor chip is transmitted to the heat radiating plate and is radiated to the atmosphere from the heat radiating plate. Therefore, it is possible to prevent the temperature of the uppermost semiconductor chip from rising.

Further, since the heat transfer pins are inserted through the semiconductor module and the heat radiating plate, the heat generated in the semiconductor chip located at the central portion of the semiconductor module moves to the heat transfer pin side, and passes through the heat transfer pins. The heat is transferred to the heat sink. Therefore, heat is sufficiently released even in the semiconductor chip sandwiched between the upper and lower semiconductor chips, and an increase in resistance value due to heat generation can be prevented.

A semiconductor device according to claim 2, comprising: a semiconductor chip having a through hole on a surface thereof; and a positioning pin which can be inserted into the through hole, wherein the semiconductor chips are stacked on the basis of the positioning pin. Wherein a heat radiation plate having the through hole and being inserted into the positioning pin is provided on the surface of the semiconductor chip located at the uppermost stage. According to the semiconductor device of the second aspect, the heat sink is provided on the surface of the uppermost semiconductor chip. For this reason, the heat generated in the uppermost semiconductor chip is transmitted to the heat radiating plate and is radiated to the atmosphere from the heat radiating plate. Therefore, it is possible to prevent the temperature of the uppermost semiconductor chip from rising.

Further, since positioning pins are inserted into the through holes of the semiconductor chips to be stacked and the through holes of the heat sink, heat generated in the semiconductor chips sandwiched between the upper and lower semiconductor chips moves toward the positioning pins. Heat is transferred to the heat sink via the positioning pins. Therefore, heat is sufficiently released even in the semiconductor chip sandwiched between the upper and lower semiconductor chips, and an increase in resistance value due to heat generation can be prevented.

Further, since the laminated semiconductor chips and the heat sink are fixed by the positioning pins fitted into the through holes, the semiconductor chips and the heat sink can be accurately positioned by inserting the positioning pins. It can be carried out.

According to a third aspect of the present invention, there is provided a semiconductor device having a semiconductor module in which semiconductor chips connectable in a thickness direction are stacked, and an end portion penetrating the semiconductor chip constituting the semiconductor module and having an end portion extending from the semiconductor module. And a protruding heat transfer pin. According to the semiconductor device of the third aspect, the heat generated in the semiconductor chip sandwiched between the upper and lower semiconductor chips moves to the heat transfer pin side, and the heat transfer protrudes from the uppermost and lowermost semiconductor chips. Heat is dissipated from the pins. Therefore, not only the semiconductor chips located at the uppermost and lowermost stages, but also the semiconductor chip sandwiched between the upper and lower semiconductor chips having a small exposed area to the atmosphere can surely dissipate heat, thereby increasing the resistance value due to heat generation. Can be prevented.

If the tips of the heat transfer pins projecting below the lowermost semiconductor chip are brought into contact with the substrate, a gap is formed between the substrate and the lowermost semiconductor chip, and the substrate or the lowermost semiconductor chip is formed. Insulation can be achieved without performing insulation treatment on the surface of the lowermost semiconductor chip (or both). Further, the difference in thermal expansion coefficient between the two can be absorbed by the gap, and stress can be prevented from being applied to the substrate and the semiconductor chip. Furthermore, by filling the gap formed between the substrate and the lowermost semiconductor chip with an adhesive, the bonding strength of the semiconductor device to the substrate can be increased.

A semiconductor device according to claim 4, comprising: a semiconductor chip having a through hole on a surface thereof; and a positioning pin which can be inserted into said through hole, wherein said semiconductor chips are stacked on the basis of said positioning pin. Wherein the positioning pins protrude from the surface of the semiconductor chip located at the uppermost stage and the surface of the semiconductor chip located at the lowermost stage. According to the semiconductor device of the fourth aspect, the heat generated in the semiconductor chip sandwiched between the upper and lower semiconductor chips moves to the positioning pin side, and the heat generated from the positioning pins protruding from the uppermost and lowermost semiconductor chips. Heat is dissipated. Therefore, not only the semiconductor chips located at the uppermost and lowermost stages, but also the semiconductor chip sandwiched between the upper and lower semiconductor chips having a small exposed area to the atmosphere can surely dissipate heat, thereby increasing the resistance value due to heat generation. Can be prevented.

If the tip of the positioning pin protruding downward from the lowermost semiconductor chip is brought into contact with the substrate, a gap is formed between the substrate and the lowermost semiconductor chip, and the substrate or the lowermost semiconductor chip is formed. Insulation can be achieved without performing insulation treatment on the surface of the lower semiconductor chip (or both). Further, the difference in thermal expansion coefficient between the two can be absorbed by the gap, and stress can be prevented from being applied to the substrate and the semiconductor chip. Furthermore, by filling the gap formed between the substrate and the lowermost semiconductor chip with an adhesive, the bonding strength of the semiconductor device to the substrate can be increased.

Further, since the stacked semiconductor chips and the heat sink are fixed by positioning pins fitted into the through holes, the semiconductor chips and the heat sink can be accurately positioned by inserting the positioning pins. It can be carried out.

A semiconductor device according to a fifth aspect of the present invention is characterized in that a heat transfer layer is formed on a surface of the semiconductor chip, and the heat transfer layer can be brought into contact with the heat transfer pins. According to the semiconductor device of the fifth aspect, since the heat transfer layer having good thermal conductivity is in contact with the heat transfer pins, the semiconductor chip located at the uppermost and lowermost stages as well as the exposure to the atmosphere is achieved. Heat can be reliably transmitted to the heat transfer pins even in a semiconductor chip having a small area and sandwiched between the upper and lower semiconductor chips. Therefore, it is possible to further reliably prevent the resistance value from increasing due to heat generation.

A semiconductor device according to a sixth aspect is characterized in that a heat transfer layer is formed on the surface of the semiconductor chip, and the heat transfer layer can be brought into contact with the positioning pins. According to the semiconductor device of the sixth aspect, since the heat transfer layer having good thermal conductivity is in contact with the positioning pins, the exposed area to the atmosphere as well as the semiconductor chips located at the uppermost and lowermost stages. The heat can be reliably transmitted to the positioning pins even in a semiconductor chip sandwiched between the semiconductor chips at the upper and lower portions. Therefore, it is possible to further reliably prevent the resistance value from increasing due to heat generation.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of a semiconductor device according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory cross-sectional view of a first example showing a structure of a semiconductor device according to the present embodiment, and FIG. 2 is a sectional view of a second example showing a structure of the semiconductor device according to the present embodiment. It is sectional explanatory drawing.

As shown in FIG. 1, a first semiconductor device 10 according to the present embodiment includes a semiconductor chip 12 serving as a plurality of (three in the figure) semiconductor modules, a heat radiating plate 14, and a semiconductor chip 12. And a positioning pin 15 that penetrates through the heat sink 14 and fixes the semiconductor chip 12 and the heat sink 14.

The semiconductor chip 12 has a resistor (not shown)
Elements such as capacitors and transistors are formed, and metal wires are routed from these elements to the front and back surfaces of the semiconductor chip. The metal wiring routed on the front and back surfaces of the semiconductor chip includes another semiconductor chip 1
2, and an electrode for electrical conduction is formed. In the semiconductor chip 12, a through hole 16 is provided so as to penetrate the front and back surfaces thereof.
6 is set as a reference. That is, the through hole 16
When the semiconductor chips 12 are stacked on the basis of the above, the electrodes formed on the front and back surfaces of the semiconductor chip 12 are accurately aligned with the electrodes formed on the upper and / or lower (or both) semiconductor chips. Electrical conduction of the semiconductor chip 12 in the lower stage can be ensured.

Further, the semiconductor chip 1 thus stacked
The heat sink 14 is mounted on the upper surface 18 of the semiconductor chip 12 </ b> A located at the uppermost stage of the semiconductor chip 12. The heat radiating plate 14 is generally formed of a metal material having high thermal conductivity, and a portion making contact with the upper surface 18 of the semiconductor chip 12A is formed flat so as to correspond to the upper surface 18 for the purpose of improving heat transfer efficiency. Have been. A plurality of fins 20 are provided on the opposite side of the surface contacting the upper surface 18 so as to increase the contact area with the air. The heat sink 14 is also provided with a through hole 16 similar to that of the semiconductor chip 12, and the positioning with the semiconductor chip 12 can be performed by using the through hole 16 as a reference.

The positioning pin 15 has an outer diameter enough to fit in the through hole 16 and a fitting portion 15A having a length corresponding to the stacked semiconductor chip 12 and heat sink 14. The head 15 provided on one side of the fitting portion 15A and having a diameter larger than the diameter of the through hole 16.
B. The material of the positioning pin 15 may be a material having good thermal conductivity, and more specifically, a metal material typified by copper or a material having a thermal conductivity characteristic similar to a metal material.

As described above, the semiconductor chip 12 and the heat sink 1
The first semiconductor device 10 composed of the positioning pins 15 and the positioning pins 15 is positioned such that the head 15B of the positioning pins 15 is positioned on the fin 20 side of the heat sink 14.
Into the through hole 16 of the heat sink 14. Then heat sink 1
The through holes 16 of the semiconductor chip 12 are inserted into the positioning pins 15 so that the upper surface 18 of the semiconductor chip 12 is in close contact with the bottom surface of the semiconductor chip 4. When the through holes 16 of the semiconductor chip 12 are inserted into the positioning pins 15 and the positioning pins 15 are used as a reference, the electrodes formed on the front and back surfaces of the semiconductor chip 12 can be reliably butted against each other.

In the first semiconductor device 10 assembled as described above, since the uppermost semiconductor chip 12A is in direct contact with the heat sink 14, heat generated in the semiconductor chip 12A via the upper surface 18 is removed. By transmitting heat to the heat radiating plate 14 and radiating the heat from the heat radiating plate 14 to the atmosphere, it is possible to prevent the temperature of the semiconductor chip 12A from rising, so that the operation of the semiconductor chip 12A can be reliably performed.

The heat generated in the semiconductor chips 12B and 12C is transmitted from the side walls of the through holes 16 in these semiconductor chips to the positioning pins 15, and
The heat is transferred to the heat radiating plate 15 via the positioning pin 15 and is radiated from the heat radiating plate 14 (for the heat transfer state, see the arrow in the figure). Therefore, even in the semiconductor chip 12 not in contact with the heat radiating plate 14, especially the semiconductor chip 12B sandwiched between the upper and lower semiconductor chips 12A and 12C, heat is transmitted to the heat radiating plate 14 through the positioning pins 15, so that heat is transferred to the semiconductor chip 12B. Is not accumulated, and a stable operation can be performed.

FIG. 2 shows a second embodiment of the semiconductor device according to the present invention. As shown in the figure, the second semiconductor device 22 is a semiconductor chip 1 of the first semiconductor device 10.
2 and a positioning pin 26. Since the semiconductor chip 24 is the same as the semiconductor chip 12 described above,
The description is omitted together with 8.

The positioning pin 26 is composed of a fitting portion 26A having an outer diameter enough to fit into the through hole 26 and a bottom portion 26B for joining with the board 30 to be mounted. The length of the fitting portion 26 </ b> A is
Are set to be longer than the thickness in which the layers are stacked.

In such a semiconductor device 22, the semiconductor chip 2 located at the uppermost part of the stacked semiconductor chips 24
The fitting portion 26A of the positioning pin 26 protrudes from the upper surface 32 of 4A, and the bottom portion 26B protrudes from the lower surface 34 of the semiconductor chip 24B located at the lowermost portion of the semiconductor chip 24. And such a semiconductor device 22
When the semiconductor chip 24 is mounted on the substrate 30, the gap 36 is formed in a portion corresponding to the thickness of the bottom portion 26B, and an air circulation path is formed, so that the heat dissipation effect of the semiconductor chip 24 can be improved. In addition, since the gap 36 is formed between the substrate 30 and the semiconductor chip 24B, even if there is a difference in the coefficient of thermal expansion between the two, the gap 36 absorbs the difference. It can be prevented from joining. If the gap 36 is filled with an adhesive, the bonding strength between the two can be increased, and the impact resistance can be improved.

Further, since heat is released from the fitting portion 26A protruding from the upper surface 32, even if the semiconductor chip 24 sandwiched between the upper and lower semiconductor chips 24 exists, the heat is positioned through the through hole 28. Since the power is transmitted to the pins 26 and is released into the atmosphere from the protruding fitting portion 26A, the temperature of the semiconductor chip 24 can be prevented from rising. Further, the heat generated in the semiconductor chip 24 is transmitted not only to the fitting portion 26A of the positioning pin 26 but also to the bottom portion 26B side and is radiated from the gap 36 or is transmitted to the substrate 30 side. The temperature rise of the semiconductor chip 24 can be prevented.

FIG. 3 is a sectional view of a semiconductor device designed to improve the efficiency of heat transfer to the positioning pins. As shown in the figure, a heat transfer layer 42 made of a metal material such as copper or aluminum is formed on the bottom surface of the semiconductor chip 38 via an insulating layer 40 for preventing short circuit. And the heat transfer layer 42
It has a form protruding from the side wall of the through hole 44, and can contact a positioning pin 46 inserted into the through hole 44. Thus, the heat transfer layer 42 is
Is contacted with the heat transfer layer 4 having a good thermal conductivity.
Since heat is transferred to the positioning pin 46 via the second pin 2, heat can be more efficiently dissipated. Therefore, even if the semiconductor chip 38 is operated at a high speed (high clock) and the amount of heat generation increases, no heat is accumulated in the semiconductor chip 38, and a rise in the resistance value can be prevented. , And the semiconductor device 48 can be operated stably.

Needless to say, the semiconductor chips to be stacked and the heat sink can be accurately positioned with respect to each other and the heat sink by positioning pins fitted into the through holes.

By the way, it is needless to say that the semiconductor chips and the radiator plate can be accurately positioned between the semiconductor chips and the radiator plate by the positioning pins fitted into the through holes. Without limitation, the positioning pin may be a heat transfer pin penetrating the semiconductor chip and the heat sink (having no positioning function). Although the positioning pin 15 is formed by the fitting portion 15A and the head portion 15B, the present invention is not limited to this configuration, and the positioning pin 15 may be in the form of only the fitting portion 15A without the head portion 15B. . Further, the positioning pin may be attached to the semiconductor chip or the like by any method as long as the heat transfer from the semiconductor chip to the pin is performed well. For example, press-fitting, bonding, and other attachment methods may be used.

[0036]

As described above, according to the present invention, a semiconductor module in which semiconductor chips that can be connected in the thickness direction are stacked, a radiator plate that is in close contact with the surface of the semiconductor module, and the semiconductor module Having a heat transfer pin that penetrates the semiconductor chip and the heat sink, a semiconductor module in which semiconductor chips connectable in a thickness direction are stacked, and a semiconductor module that constitutes the semiconductor module. Since the end portion has the heat transfer pin protruding from the semiconductor module, sufficient heat radiation can be performed even in the semiconductor chip sandwiched between the upper and lower semiconductor chips, and also sufficient in the semiconductor chip positioned above and below. Heat can be dissipated.

Further, in addition to the above effects, a semiconductor device comprising a semiconductor chip having a through hole on a surface thereof and a positioning pin insertable into the through hole, wherein the semiconductor chips are stacked on the basis of the positioning pin, Providing a heat sink that has the through hole on the surface of the semiconductor chip located at the top and is inserted into the positioning pin;
Alternatively, a semiconductor device comprising a semiconductor chip having a through hole on a surface thereof and a positioning pin insertable into the through hole, wherein the semiconductor chip is stacked on the basis of the positioning pin, wherein the positioning pin is positioned at the uppermost stage. Since the semiconductor chip and the heat sink are protruded from the surface of the semiconductor chip and the surface of the lowermost semiconductor chip, positioning of the stacked semiconductor chips and the heat sink by inserting the positioning pins can be easily performed.

[Brief description of the drawings]

FIG. 1 is an explanatory sectional view of a first example showing the structure of a semiconductor device according to the present embodiment.

FIG. 2 is an explanatory sectional view of a second example showing the structure of the semiconductor device according to the present embodiment;

FIG. 3 is a cross-sectional explanatory view of a semiconductor device designed to improve the efficiency of heat transfer to positioning pins.

[Explanation of symbols]

 Reference Signs List 10 first semiconductor device 12 (12A, 12B, 12C) semiconductor chip 14 heat sink 15 positioning pin 15A fitting portion 15B head 16 through hole 18 upper surface 20 fin 22 second semiconductor device 24 semiconductor chip 3 26 positioning pin 26A fitting Part 26B Bottom part 28 Through hole 30 Substrate 32 Upper surface 34 Lower surface 36 Gap 38 Semiconductor chip 40 Insulating layer 42 Heat transfer layer 44 Through hole 46 Positioning pin 48 Semiconductor device

Claims (6)

[Claims] 1. A semiconductor module in which semiconductor chips connectable in a thickness direction are stacked, a radiator plate closely attached to a surface of the semiconductor module, and a penetrating through the semiconductor chip and the radiator plate constituting the semiconductor module. A semiconductor device comprising: a heat transfer pin. 2. A semiconductor chip having a through hole on a surface thereof;
It consists of a positioning pin that can be inserted into the through hole,
A semiconductor device in which the semiconductor chips are stacked on the basis of the positioning pins, wherein a heat radiating plate having the through hole is provided on a surface of the uppermost semiconductor chip and inserted through the positioning pins. Semiconductor device. 3. A semiconductor module in which semiconductor chips connectable in a thickness direction are stacked, and a heat transfer pin penetrating through the semiconductor chip constituting the semiconductor module and having an end protruding from the semiconductor module. A semiconductor device characterized by the above-mentioned. 4. A semiconductor chip having a through hole on a surface,
It consists of a positioning pin that can be inserted into the through hole,
A semiconductor device in which the semiconductor chips are stacked on the basis of the positioning pins, wherein the positioning pins protrude from a surface of the semiconductor chip positioned at an uppermost level and a surface of the semiconductor chip positioned at a lowermost level. A semiconductor device characterized by the above-mentioned. 5. The semiconductor device according to claim 1, wherein a heat transfer layer is formed on a surface of the semiconductor chip, and the heat transfer layer is brought into contact with the heat transfer pins. 6. The semiconductor device according to claim 2, wherein a heat transfer layer is formed on a surface of the semiconductor chip, and the heat transfer layer is brought into contact with the positioning pins.