JPH04122054A - Semiconductor device - Google Patents

Abstract

PURPOSE:To improve heat dissipation efficiency of a semiconductor device and a pellet, to improve circuit operation performance and to reduce a stress applied to a semiconductor pellet by making a rear of the semiconductor pellet form a part of a heat exchange flow path and by providing a cooling jacket, etc. CONSTITUTION:Since a rear of a semiconductor pellet 2 forms a part of a heat exchange flow path 8 in a semiconductor device 1 of microchip carrier structure, a heat conduction path from a circuit mount surface of the pellet 2 to a circulating cooling fluid is reduced, thereby reducing heat resistance. Therefore, it is possible to improve heat dissipation efficiency and to improve circuit operation performance of the device 1. The pellet 2 is mounted on a package substrate (wiring substrate) 3 and covered with a cooling jacket 5 which constitutes other part of the flow path 8; therefore, a rear of the pellet 2 which is a part of the flow path 8 and the jacket 5 which is other part thereof are connected through an elastic body 5A. Thereby, thermal stress or mechanical stress generated in each of the substrate 3 and the jacket 5 or between both thereof and an external force applied from a circulation pipe 9, etc., are absorbed by an elastic body 5A, thereby reducing transmission of each stress to the pellet 2 through the jacket 5.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a semiconductor device, and in particular, to a technology that is effective when applied to a semiconductor device for forcibly dissipating heat generated by circuit operation of a semiconductor pellet. It is.

[Conventional technology]

2. Description of the Related Art Semiconductor devices having a microchip carrier (MMC) structure used in supercomputers, large computers, etc. are incorporated into cooling systems.

The semiconductor device having the microchip carrier structure has a structure in which a semiconductor pellet mounted on a package substrate is sealed with a sealing cap. Semiconductor pellet is CCB
(Controlled Colapse B.

nding structure (or TAB structure) and is mounted on the package substrate via solder electrodes (or beam leads). The solder electrode electrically and mechanically connects the external terminal (ponding pad) formed on the circuit mounting surface side of the semiconductor pellet and the terminal of the package substrate.

The cooling system individually cools a plurality of semiconductor devices having a microchip carrier structure mounted on a module substrate. In the semiconductor device having the microchip carrier structure, heat is generated due to the @path operation of the semiconductor pellet, specifically, at the pn junction of the semiconductor element. Circuits mounted on the circuit mounting surface of semiconductor pellets tend to generate more heat due to higher density, higher power consumption, etc., and the temperature rise associated with this increase in heat generation deteriorates circuit characteristics. A semiconductor device having a microchip carrier structure conducts heat generated on the circuit mounting surface side of the semiconductor pellet to the back surface side, and radiates this conducted heat to the outside via a sealing cap.

In the cooling system, an elastic heat transfer element is brought into contact with a sealing cap of a semiconductor device having a microchip carrier structure, and the aforementioned heat is absorbed into the circulating cooling fluid through the elastic heat transfer element. The elastic heat transfer element provides a heat exchange channel between the semiconductor device of the microchip carrier structure and the circulating cooling fluid. A circulating cooling fluid is supplied to this elastic heat transfer element within a space closed by a heat transfer plate and a bellows mechanism that contact the sealing cap of a semiconductor device having a microchip carrier structure. A thermal compound (e.g., grease material) is interposed between the heat transfer plate of the elastic heat transfer element and the sealing cap of the semiconductor device with the microchip carrier structure to increase the adhesion between the two and to reduce thermal resistance. . Water having a large heat capacity is used as the circulating cooling fluid. The circulating cooling fluid circulates between the semiconductor device having the microchip carrier structure and the heat exchanger, and the heat absorbed by the former is dissipated by the latter. VP2000 Series Technology J, FUJ I TU, 41.

1, (01, 1990), pages 12 to 19.

[Problem to be solved by the invention]

In the cooling system described above, heat generated on the circuit mounting surface side of the semiconductor pellet of the semiconductor device having the microchip carrier structure is dissipated to the circulating cooling fluid through the sealing cap and the elastic heat transfer element.

For this reason, no consideration has been given to the fact that the thermal resistance between the semiconductor pellets and the circulating cooling fluid increases, making it impossible to expect sufficient heat dissipation efficiency from a semiconductor device having a microchip carrier structure.

A first object of the present invention is to improve heat dissipation efficiency and circuit operation performance in a semiconductor device that dissipates heat generated by circuit operation of semiconductor pellets into a circulating cooling fluid supplied from a cooling fluid supply device. Our goal is to provide the technology that is possible.

A second object of the present invention is to provide a technique that can achieve the first object, reduce the thermal resistance of the semiconductor pellet itself, and further improve heat dissipation efficiency.

A third object of the present invention is to provide a technique that can achieve the first object and reduce stress applied to semiconductor pellets.

A fourth object of the present invention is to provide a technique that can achieve the first or second object and improve the packaging density of semiconductor devices.

A fifth object of the present invention is to provide a technique capable of achieving any of the first to fourth objects and improving the reliability of circuit operation of semiconductor pellets.

A sixth object of the present invention is to provide a technique that can achieve any of the first to fifth objects and improve the heat dissipation efficiency of a semiconductor device.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

A brief summary of representative inventions among the inventions disclosed herein is as follows.

(1) In a semiconductor device in which heat generated by the circuit operation of a semiconductor pellet is dissipated from the circuit mounting surface of the semiconductor pellet or its back surface into the circulating cooling fluid supplied from the cooling fluid supply device, the circuit mounting surface of the semiconductor pellet is provided. Alternatively, the back surface constitutes a part of a heat exchange channel that directly contacts the circulating cooling fluid.

(2) In a semiconductor device in which heat generated by the circuit operation of a semiconductor pellet is dissipated from the back surface of the circuit mounting surface of the semiconductor pellet in the circulating cooling fluid supplied from the cooling fluid supply device, a recess is provided on the back surface of the semiconductor pellet. The concave portion on the back surface of the semiconductor pellet constitutes a part of a heat exchange channel that directly contacts the circulating cooling fluid.

(3) The semiconductor pellet of the means (1) or (2) is mounted on a wiring board and covered with a cooling jacket that constitutes the other part of the heat exchange channel, and is a part of the heat exchange channel. The circuit mounting surface or back surface of the semiconductor pellet and the cooling jacket, which is the other part, are connected via an elastic body.

(4) In a semiconductor device in which the heat generated by the circuit operation of the semiconductor pellet is dissipated from the circuit mounting surface of the semiconductor pellet or its back surface in the circulating cooling fluid supplied from the cooling fluid supply device, the circuit is mounted on the first semiconductor pellet. Either the circuit mounting surface or the back surface of the second semiconductor pellet is arranged to face the front or back surface, and the circuit mounting surface or the back surface of the first semiconductor pellet and the circuit mounting surface of the second semiconductor pellet facing thereto; Either of the back surfaces constitutes a part of the heat exchange channel that is in direct contact with the circulating cooling fluid.

(5) A plurality of heat exchange channels according to any one of the means (1) to (4) are arranged in a direction perpendicular to the circulation direction of the circulating cooling fluid, and each of the adjacent heat exchange channels The direction of circulation of the cooling fluid is countercurrent.

(6) Water is used as the circulating cooling fluid in any of the means (1) to (5).

[For production]

According to the above-mentioned means (1), the heat conduction path from the circuit mounting surface of the semiconductor pellet to the circulating cooling fluid is shortened,
Since thermal resistance can be reduced, heat dissipation efficiency can be increased and circuit operation performance of a semiconductor device can be improved.

According to the above-mentioned means (2), in addition to the effect of the above-mentioned means (1), the heat conduction path (dimension in the thickness direction of the semiconductor pellet) from the circuit mounting surface to the back surface of the semiconductor pellet is shortened, Since thermal resistance can be reduced, heat dissipation efficiency can be increased and circuit operation performance of a semiconductor device can be improved.

According to the above-mentioned means (3), the above-mentioned means (1) or (2)
In addition to the effects of ), the elastic body absorbs thermal stress or mechanical stress occurring in or between the wiring board and the cooling jacket, and the stress is transmitted to the semiconductor pellet through the cooling jacket. This can reduce the As a result,
When the circuit mounting surface of the semiconductor pellet is made a part of the heat exchange channel, damage and destruction of the circuit mounting surface of the semiconductor pellet can be prevented. Further, when the back surface of the semiconductor pellet is used as a part of the heat exchange channel and the semiconductor pellet is mounted on a wiring board in a chip carrier structure, damage or destruction of the solder electrode can be prevented.

According to the above-mentioned means (4), in addition to the effect of the above-mentioned means (1), all or part of the second semiconductor pellet is arranged within the area occupied by the first semiconductor pellet, and the first semiconductor pellet and Since the total occupied area of the second semiconductor pellets is reduced, the packaging density of the semiconductor device can be improved.

According to the above-mentioned means (5), the temperature gradient of the circulating cooling fluid is offset and made uniform, and the circuit mounting surface or back surface of the semiconductor pellet can be uniformly cooled.

The reliability of circuit operation of semiconductor pellets can be improved.

According to the above-mentioned means (6), the heat capacity of the circulating cooling fluid can be maximized, so that the heat dissipation efficiency of the heat generated by the circuit operation of the semiconductor pellet can be increased.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described below along with an embodiment in which the present invention is applied to a cooling system in which a semiconductor device having a microchip carrier structure is incorporated.

In addition, in an attempt to explain the embodiments, parts having the same functions are given the same reference numerals, and repeated explanation thereof will be omitted.

[Embodiments of the invention]

(Embodiment I) FIG. 2 (schematic configuration diagram) shows a cooling system incorporating a semiconductor device having a microchip carrier structure, which is Embodiment ① of the present invention.

As shown in FIG. 2, the cooling system mainly consists of a cooling module 10 built into the processor section 11, a cooling fluid supply bag M12, and a main circulation pipe! Consists of 6.

The processor section 11 is a main control section of a supercomputer, large computer, etc., and has a cooling module l.
O constitutes this main control section. Cooling module lO
A semiconductor device [1] having a plurality of microchip carrier structures mounted on a module substrate is sealed with a module cap. , a cooling fluid is circulated through a circulation pipe 9 connected to a main circulation pipe 16 in each semiconductor device 1 having a microchip carrier structure. The circulating cooling fluid is supplied from one end of an array of semiconductor devices 1 having a plurality of microchip carrier structures, sequentially flows toward the other end of the array, and is discharged from the other end of the array.

The cooling fluid supply device 12 mainly includes a water storage tank 13, a pump 14, and a heat exchanger 15. The water storage tank 13 is connected to the processor section 1 through a main circulation pipe 16.
The circulating cooling fluid is stored for the purpose of supplying the circulating cooling fluid to one cooling module 10 . The heat exchanger 15 dissipates the heat absorbed by the circulating cooling fluid exhausted from the cooling module 11 through the main circulation pipe 18 . pump 14
supplies the circulating cooling fluid from which heat has been dissipated in the heat exchanger 15 to the water storage tank 13.

Although water having the largest heat capacity is used as the circulating cooling fluid, it is basically not limited to water.

Next, the processor section! A specific configuration of a semiconductor device 1 having a microchip carrier structure mounted on a cooling module 1O will be briefly described using FIG. 1 (cross-sectional view).

The semiconductor device ill with the microchip carrier structure has the first
As shown in the figure, it is mainly composed of a package substrate 3, a cooling jacket 5, and semiconductor pellets 2.

The package substrate 3 has a multilayer wiring structure. One end side of the wiring of the multilayer wiring structure of the package board 3 is connected to a terminal on the module board of the cooling module IO of the processor section 11. The other end of the wiring in the multilayer wiring structure is connected to an external terminal (ponding pad) of the semiconductor chip. The package substrate 3 is made of a ceramic material such as alumina or mullite.

The semiconductor pellet 2 is composed of, for example, a single crystal silicon substrate, and a circuit system is mounted on the circuit mounting surface (lower surface in FIG. 1). The above-mentioned external terminals are arranged on the circuit mounting surface side of the semiconductor pellet 2, and are formed of, for example, an aluminum alloy film that connects the inside of the circuit system. On this aluminum alloy film serving as an external terminal, a Cr film, a Cu film, and an Au film were sequentially laminated from the bottom layer to the top layer. A base metal layer is formed. Moreover, the semiconductor pellet 2 is GaA
It may also be composed of an s-substrate.

The semiconductor pellet 2 is mounted on a package substrate 3 in a chip carrier structure (face-down structure or CCB structure). That is, the semiconductor pellet 2 is mounted on the package substrate a via the solder electrode (projection electrode, bump electrode, or CCB electrode) 4.

As the solder electrode 4, for example, Pb-8n solder, Pb-I
N-based solder or the like is used.

The cooling jacket 5 is attached to the package substrate 3 at its periphery, and the attachment of the cooling jacket 5 to the six-package substrate 3 covering the semiconductor pellet 2 is carried out with a sealing adhesive 6.

The sealing bonding agent 6 is, for example, Pb-5n solder.

Pb-Ag-based solder, Pb-Ag-Sn-based solder, Pb-Ag-In-based solder, etc. are used. When the semiconductor pellet 2 is formed of a single-crystal silicon substrate, the cooling jacket 5 is made of a material having a similar coefficient of thermal expansion, such as W, Mo, or AQ.
It is made of materials such as N, SiC, and T-CBN. Also,
In the cooling jacket 5, the semiconductor pellet 2 is G a A
When formed with s substrate, Cu-W based composite material, Cu-
Mo-based composite materials etc.A Q20. + B e O etc.

In the cooling jacket 5, a circulation pipe 9 for supplying circulating cooling fluid is connected to the upper left side of FIG. 1, and a circulation pipe 9 for discharging circulating cooling fluid is connected to the upper right side. The direction of circulation of the circulating cooling fluid is indicated by arrows in FIG. In other words, this cooling jacket 5.

The circulating cooling fluid circulated in the circulation pipe 9 absorbs the heat generated by the operation of the circuit system of the semiconductor pellet 5, thereby cooling the semiconductor pellet 2. The cooling jacket 5 is connected to the R1# portion of the back surface of the semiconductor pellet 2, which faces the circuit mounting surface, via an elastic material 5A. The elastic material 5A is composed of an elastic thin film (flexible thin plate) made of a single layer or multiple layers of metal foil. Specifically, the elastic material 5A is made of, for example, Ni or Cu.
, Co.

It is formed of one of Au, etc., or an alloy of two or more of these metals. The elastic material 5A is connected to the back surface of the semiconductor pellet 2 via a bonding layer 7 that is substantially the same as the sealing bonding material 6 6 Also, the elastic material 5A is connected to the circuit mounting surface side and the back surface side of the semiconductor pellet 2. partition each of the
A heat exchange channel 8 is formed on the back side of the semiconductor pellet 2, and airtightness on the circuit mounting side of the semiconductor pellet 2 is ensured.

The cooling jacket 5 allows the circulating cooling fluid supplied by the circulating pipe 9 to directly contact the back surface of the semiconductor pellet 2,
The heat exchange channel 8 described above is configured to absorb the heat generated in the circuit system of the semiconductor pellet 2 into the circulating cooling fluid and discharge the circulating cooling fluid to the circulating pipe 9. That is, the back surface of the semiconductor pellet 2 constitutes a part of this heat exchange channel 8.

In addition, cooling jacket 5. The elastic material 5A connecting the back surfaces of the semiconductor pellets 2 similarly constitutes a part of the heat exchange channel 8.

The circulation pipe 9 has a bellows structure, and has a degree of freedom in deforming vertically and horizontally.

Next, the semiconductor device I of the above-mentioned microchip carrier structure is
The method of assembling f will be briefly explained using FIGS. 3 and 4 (cross-sectional views showing each assembly process).

First, the semiconductor pellet 2 is mounted on the package substrate a in a chip carrier structure. That is, the semiconductor pellet 2 is mounted on the package substrate 3 via the solder electrode 4.

Next, as shown in FIG. 3, a cooling jacket 5 is attached to the peripheral edge of the package substrate 3, and an elastic member 5A connected to the cooling jacket 5 is connected to the back surface of the semiconductor pellet 2. Package board 3, cooling jacket 5
are attached via a sealing bonding layer 6. Elastic material 5A,
The back surfaces of the semiconductor pellets 2 are connected via a bonding layer 7.

The brazing materials for each of the sealing bonding layer 6 and the bonding layer 7 are supplied by preform or vapor deposition. Moreover, a base metal layer is formed on the surface to which the sealing bonding layer 6 and the bonding layer 7 are respectively supplied in order to improve wettability and adhesion. This base metal layer is formed, for example, from a composite film in which an adhesive layer, a barrier layer, and an anti-oxidation layer are laminated in sequence. The adhesive layer is made of Cr, for example.

Metal materials such as Ti and W are used. N as a barrier layer
Metal materials such as i, Cu, Pt, Pd, and Mo are used.

For example, Au is used as the anti-oxidation layer.

This assembly process also includes the sealing bonding layer 6. This is carried out in a heated atmosphere in order to melt the respective brazing materials of the bonding layer 7. This heating atmosphere is filled with an inert gas containing 10 ppm or less of 02 or a gas to which 10 to 20 weight percent of H2 is added. As a result, the circuit mounting surface side of the semiconductor pellet 2, which is sealed with the package substrate 3 and the cooling jacket 5 and hermetically sealed with the elastic material 5A, is filled with the above-mentioned atmosphere. Then, a semiconductor electronics device with a microchip carrier structure is completed.

Next, the semiconductor device l having the microchip carrier structure is
is mounted on the module substrate of the cooling module 10 of the processor section 11. As shown in FIG. 4, a circulation pipe 9 is connected to each of the supply side and the discharge side of the heat exchange channel 8 of the cooling jacket 5 of the semiconductor device 1 having a microchip carrier structure.

Thereafter, a plurality of semiconductor components having a microchip carrier structure are sealed with a module cap of the cooling module 10. Then, by connecting the main circulation pipe 16 to the cooling module 10, the above-mentioned cooling system is completed.

In this way, the semiconductor device has a microchip carrier structure in which the heat generated by the circuit operation of the semiconductor pellet 2 is radiated from the back surface of the semiconductor pellet 2 to the circulating cooling fluid supplied from the cooling fluid supply device 12! ! 1, the back surface of the semiconductor pellet 2 constitutes a part of a heat exchange channel 8 that directly contacts the circulating cooling fluid. With this configuration, it is possible to shorten the heat conduction path from the circuit mounting surface of the semiconductor pellet 2 to the circulating cooling fluid and reduce thermal resistance, thereby increasing heat dissipation efficiency.
The circuit operating performance can be improved.

Further, the semiconductor pellet 2 is mounted on a package substrate (wiring board) a and is covered with a cooling jacket 5 constituting the other part of the heat exchange channel 8. The back surface of the pellet 2 and the cooling jacket 5, which is the other part, are connected to each other via an elastic body 5A. With this configuration, in addition to the above-mentioned effects, the package substrate 3
The elastic body 5A absorbs the thermal stress or mechanical stress generated in each of the cooling jackets 6 or between the two, and the external force applied from the circulation pipe 9, etc., and the stress is transmitted to the semiconductor pellet 2 through the cooling jacket 5. It is possible to reduce the risk of As a result, in a semiconductor device l having a microchip carrier structure in which the back surface of the semiconductor pellet 2 is used as a part of the heat exchange channel 8 and the semiconductor pellet 2 is mounted on a package substrate 3 in a chip carrier structure, the solder electrode 4 may be damaged or destroyed. can be prevented.

Further, in the semiconductor device 1 having the microchip carrier structure, the heat exchange channel 8 is formed in the cooling jacket 5, and a cooling mechanism is incorporated therein, so that the size can be reduced by an amount corresponding to a conventional cooling mechanism. As a result, the cooling module 10 itself of the cooling system can also be downsized.

In addition, water is used as the circulating cooling fluid. With this configuration, the heat capacity of the circulating cooling fluid can be maximized, so that the heat dissipation efficiency of the heat generated by the circuit operation of the semiconductor pellet 2 can be further improved.

(Embodiment 2) This embodiment 2 is a second embodiment of the present invention in which the semiconductor device having the above-mentioned microchip carrier structure is miniaturized.

FIG. 5 (cross-sectional view) shows a semiconductor device having a microchip carrier structure, which is Embodiment 2 of the present invention.

In the semiconductor device 1 having the microchip carrier structure of Example 2, a cooling jacket 5 is attached directly to the back surface of the semiconductor pellet 2, as shown in FIG.

The cooling jacket 5 is connected to the peripheral edge of the back surface of the semiconductor pellet 2 via the sealing bonding layer 6 . In the basic cooling structure, the back surface of the semiconductor pellet 2 constitutes a part of the heat exchange channel 8, similar to the above-mentioned Example I.

The circuit mounting surface side of the semiconductor pellet 2 has a non-airtight structure.

In this way, the semiconductor device 1 with the microchip carrier structure
At i1, a cooling jacket 5 is formed on the back surface of the semiconductor pellet 2 within a region substantially defined on the back surface.

With this configuration, the cooling jacket 5 is accommodated within the planar size of the semiconductor pellet 2, so that the direct weight of the semiconductor device of the microchip carrier structure can be reduced.

Further, the semiconductor device 1 having the microchip carrier structure
In the cooling jacket 5. Since parts such as the elastic material 5A that connect the semiconductor pellets 2 can be eliminated, the number of parts can be reduced and the structure can be simplified.

Moreover, since the cooling jacket 5 can be placed on the back surface of the semiconductor pellet 2 within its area, a large number of signal wirings can be placed in a limited space, resulting in a bare chip mounting structure that maximizes the performance of high-speed devices. The present invention is applicable.

Note that the method for assembling the semiconductor device with the microchip carrier structure of this example is substantially the same as that of Example I, so a description thereof will be omitted here.

(Example 2) Example 2 is a third example of the present invention in which the thermal resistance of the semiconductor pellet itself is reduced in the semiconductor device having the microchip carrier structure.

FIG. 6 (cross-sectional view) shows a semiconductor device having a microchip carrier structure, which is Embodiment 2 of the present invention.

As shown in FIG. 6, the semiconductor device 1 having the microchip carrier structure of the present embodiment (2) has a recess 2A formed in the thickness direction on the back surface of the semiconductor pellet 2, which becomes a part of the heat exchange channel 8. is configured. This recess 2A is configured for the purpose of shortening the distance from the circuit mounting surface to the back surface of the semiconductor pellet 2 and reducing thermal resistance. Further, the recessed portion 2A allows the thickness of the peripheral edge of the semiconductor pellet 2 to remain unchanged, thereby ensuring mechanical strength when attaching the cooling jacket 5.

Although the recess 2A can be formed by anisotropic etching, it is preferably formed by isotropic etching from the viewpoint of shortening processing time and stress relaxation due to the cross-sectional shape. In addition, a very thin natural silicon oxide film is formed on the surface of the recess 2A that is in direct contact with the circulating cooling fluid, but since this increases thermal resistance, basically a thick silicon oxide film is actively added to the surface. Does not form a film.

Like this, cooling fluid supply bag! In the semiconductor device 11 having a microchip carrier structure, the heat generated by the circuit operation of the semiconductor pellet 2 is dissipated from the back surface of the circuit mounting surface of the semiconductor pellet 2 to the circulating cooling fluid supplied from the semiconductor pellet 12. A recess 2A is formed on the back surface of the semiconductor pellet 2, and the recess 2A on the back surface of the semiconductor pellet 2 forms a part of the heat exchange channel 8 that directly contacts the circulating cooling fluid. With this configuration, in addition to the effects of Example I, the heat conduction path (dimension in the thickness direction of the semiconductor pellet 2) from the circuit mounting surface to the back surface of the semiconductor pellet 2 can be shortened, and the thermal resistance can be reduced. Therefore, the heat dissipation efficiency can be increased and the circuit operation performance of the semiconductor device 1 having the microchip carrier structure can be improved.

Further, this embodiment (2) can also be applied to the above-mentioned embodiment (2), and is particularly effective when the semiconductor pellet 2 is a GaAs substrate with low thermal conductivity.

(Example 2) This example 2 is a fourth example of the present invention in which the packaging density of the semiconductor device having the microchip carrier structure is improved.

A semiconductor device having a microchip carrier structure, which is Embodiment 2 of the present invention, is shown in FIG. 7 (cross-sectional view) and FIG. 8 (side view).

As shown in FIGS. 7 and 8, the semiconductor device 1 having a microchip carrier structure according to the present embodiment (2) has a lower semiconductor pellet 2.0 mounted on a lower package substrate 3. Upper semiconductor pellet 2 mounted on upper package substrate 3
The back surfaces of each are bonded to each other via a bonding layer 20. On the back surface of each of the upper and lower semiconductor pellets 2, a groove having a U-shaped cross section (V-shaped or concave shape) is formed at almost the same position from one side of the semiconductor pellet 2 to the other side opposite to it. be done. These grooves constitute heat exchange channels 8A and 8B, respectively, by overlapping the back surfaces of the upper and lower semiconductor pellets 2 with each other.

Each of the heat exchange channels 8A and 8B is arranged in a direction perpendicular to its extending direction (circulation direction of the circulating cooling fluid). A circulation pipe 9 is connected to one end and the other end of each of the heat exchange channels 8A and 8B.

The circulation direction of the circulating cooling fluid flowing in the heat exchange channel BA is set to be countercurrent and opposite to the circulating direction of the circulating cooling fluid flowing in the adjacent heat exchange channel 8B. In other words, the circulating cooling fluid supplied from the circulating pipe 9 has a low temperature, and the circulating cooling fluid flowing into the circulating pipe 9 absorbs the heat of the semiconductor pellet 2 and becomes high in temperature, so the circulating cooling fluid is flowed in a countercurrent flow. By canceling out the temperature gradient on the back surface of the semiconductor pellet 2, the temperature distribution can be averaged and -
Wear.

In this way, in the semiconductor device If of the microchip carrier structure in which the heat generated by the circuit operation of the semiconductor pellet 2 is dissipated from the back surface of the semiconductor pellet 2 to the circulating cooling fluid supplied from the cooling fluid supply device 12, the lower side A heat exchange channel 8 is disposed so that the back surface of the upper semiconductor pellet 2 is opposed to the back surface of the semiconductor pellet 2 , and the back surface of each of the lower and upper semiconductor pellets 2 is in direct contact with the circulating cooling fluid. (8A and 8B) are constructed. With this configuration, in addition to the effects of the first embodiment, all or a part of the upper semiconductor pellet 2 is disposed within the area occupied by the lower semiconductor pellet 2, and the lower semiconductor pellet 2 and the upper semiconductor pellet 2 are Since the total occupied area of semiconductor pellets 2 is reduced,
The packaging density of semiconductor devices If having a microchip carrier structure can be improved.

Further, the heat exchange flow path 8 includes a plurality of heat exchange flow paths 8A and 8 in a direction perpendicular to the circulation direction of the circulating cooling fluid.
The circulation directions of the circulating cooling fluids in the adjacent heat exchange channels 8A and 8B are countercurrent. With this configuration, the temperature gradient of the circulating cooling fluid can be offset and made uniform, and the back surface of the semiconductor pellet 2 can be uniformly cooled, so that the reliability of the circuit operation of the semiconductor pellet 2 can be improved.

(Embodiment V) This embodiment V is a fifth embodiment of the present invention in which a semiconductor pellet is mounted on a package substrate in a TAB structure in the semiconductor device having the microchip carrier structure.

FIG. 9 (cross-sectional view) shows a semiconductor device having a microchip carrier structure, which is Embodiment 2 of the present invention.

Semiconductor device W with microchip carrier structure of this example (■)
1, as shown in FIG. 9, the semiconductor pellet 2 is TAB
The structure is mounted on a package substrate a. That is, the semiconductor pellet 2 is mounted on the package substrate 3 via the beam lead 21. The beam lead 21 is formed of a thin elastic metal film such as Cu.

This semiconductor device 1 having a microchip carrier structure is basically similar to the above-mentioned Example I, etc., with semiconductor pellets 2
The back side of is configured as part of the heat exchange flow MrB. The back surface of the semiconductor pellet 2 and the cooling jacket 5 are directly connected to each other without intervening the elastic material 5A of Example I. Thermal stress and mechanical stress applied to the semiconductor pellet 2 can be absorbed by the beam lead 21.

In this way, the semiconductor device 1 having the microchip carrier structure can achieve substantially the same effects as those of the embodiment I described above.

Furthermore, since the elastic material 5A can be eliminated from the cooling jacket 5, the number of parts can be reduced and the structure of the semiconductor device 1 having a microchip carrier structure can be simplified.

(Embodiment 2) This embodiment 2 is a sixth embodiment of the present invention in which the circuit mounting surface of the semiconductor pellet is used as a part of the heat exchange channel in the semiconductor device having the microchip carrier structure.

A semiconductor device having a microchip carrier structure, which is Embodiment 2 of the present invention, is shown in FIGS. 10 and 11 (cross-sectional views).

Semiconductor device W with microchip carrier structure of this example (■)
1, as shown in FIG. 10, the circuit mounting surface of the semiconductor pellet 2 constitutes a part of the heat exchange channel 8. The back surface of the semiconductor pellet 2 is adhered within a recess (cavity) formed in the package substrate 3 via an adhesive layer 22. As the adhesive layer 22, Au-based eutectic material, Pb-8n-based solder, Ag paste material, etc. are used. External terminals on the circuit mounting surface side of the semiconductor pellet 2 are connected to terminals of the package substrate 3 via bonding wires 23.

The peripheral edge of the circuit mounting surface of the semiconductor pellet 2 and the cooling jacket 5 are connected to each other via an elastic material 5A that is similar to that of the embodiment I and has a greater degree of elastic freedom than that of the embodiment I. This elastic material 5A is configured to have a large degree of elastic freedom in order to prevent damage or destruction of semiconductor elements formed on the circuit mounting surface of the semiconductor pellet 2. The elastic material 5A and the circuit mounting surface of the semiconductor pellet 2 are bonded with a bonding layer 7 interposed therebetween. When the uppermost layer of the circuit mounting surface of the semiconductor pellet 2 is formed of a silicon oxide film (protective film), the bonding layer 7 is made of, for example, Aul Cr tCu,
A base metal layer is formed from a composite film in which Au and Au are laminated and bonded using a brazing material. Au is used as an adhesive layer. Cr is used as an adhesive layer with Afl, and Ti
etc. may also be used. Cu is used as a barrier layer,
Other materials such as Ni and Pt may also be used. Au is used as an anti-oxidation layer.

In this manner, in the semiconductor device 1 having the microchip carrier structure, the circuit mounting surface of the semiconductor pellet 2 is configured as a part of the heat exchange channel 8. With this configuration, it is possible to directly cool the semiconductor pellet 2 from the circuit mounting surface, which is a heat generation source, so that the thermal resistance is reduced by the thermal resistance equivalent to the thickness of the semiconductor pellet 2, and the semiconductor device 1 with the microchip carrier structure The heat dissipation efficiency can be further improved.

Further, in the semiconductor device W1 having the microchip carrier structure of the present embodiment (2), as shown in FIG. 11, a beam lead 21 may be used instead of the bonding wire 23 shown in FIG. 10.

As above, the invention made by the present inventor has been specifically explained based on the above embodiments, but the present invention is not limited to the above embodiments, and can be modified in various ways without departing from the gist thereof. Of course.

For example, in the present invention, any two or more of the embodiments I to II may be combined.

〔Effect of the invention〕

A brief explanation of the effects obtained by typical inventions disclosed in this application is as follows.

In a semiconductor device that dissipates heat generated by circuit operation of semiconductor pellets into a circulating cooling fluid supplied from a cooling fluid supply device, heat dissipation efficiency can be increased and circuit operation performance can be improved.

Moreover, the thermal resistance of the semiconductor pellet itself of the semiconductor device can be reduced, and the heat dissipation efficiency can be further improved.

Further, the above effects can be achieved, and the stress applied to the semiconductor pellet can be reduced.

Furthermore, the packaging density of the semiconductor device can be improved.

Moreover, the heat dissipation efficiency of the semiconductor device can be improved.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a semiconductor device with a microchip carrier structure, which is Embodiment 2 of the present invention; FIG. 2 is a schematic configuration diagram of a cooling system in which the semiconductor device with the microchip carrier structure is incorporated; 4 and 4 are cross-sectional views showing each assembly process for explaining the method of assembling the semiconductor device with the microchip carrier structure, and FIG. 5 is a semiconductor device with the microchip carrier structure according to the embodiment FIG. 6 is a cross-sectional view of a semiconductor device with a microchip carrier structure, which is an embodiment (2) of the present invention, and FIG. 7 is a cross-sectional view of a semiconductor device with a microchip carrier structure, which is an embodiment (2) of the present invention. The cross-sectional view, Figure 8, is
A side view of the semiconductor device with the microchip carrier structure, FIG. 9 is a sectional view of the semiconductor device with the microchip carrier structure which is Embodiment 2 of the present invention, and FIGS. 10 and 11 are Embodiments of the present invention. FIG. 3 is a cross-sectional view of a semiconductor device having a microchip carrier structure as shown in FIG. In the figure, 1... Semiconductor device with microchip carrier structure, 2... Semiconductor pellet, 2A... Concave portion, 3...
Package board, 4... Solder electrode, 5... Cooling jacket, 5A... Elastic material, 6, 7... Bonding layer, 8,
8A. 8B... Heat exchange channel, 9... Circulation pipe, 10...
・Cooling module, 11... Processor section, 12...
・Cooling fluid supply device, 21...beam lead, 23・
...It is a bonding wire.

Claims (1)

[Claims] 1. The circulating cooling fluid supplied from the cooling fluid supply device,
In a semiconductor device in which heat generated by circuit operation of a semiconductor pellet is dissipated from the circuit mounting surface of the semiconductor pellet or its back surface, a heat exchange flow in which the circuit mounting surface or the back surface of the semiconductor pellet directly contacts the circulating cooling fluid. A semiconductor device comprising a part of a circuit. 2. Circulating cooling fluid supplied from the cooling fluid supply device,
In a semiconductor device that dissipates heat generated by circuit operation of a semiconductor pellet from the back surface of the circuit mounting surface of the semiconductor pellet, a recess is formed on the back surface of the semiconductor pellet, and the recess on the back surface of the semiconductor pellet is configured to dissipate heat generated by circuit operation of the semiconductor pellet from the back surface of the circuit mounting surface of the semiconductor pellet. A semiconductor device comprising a part of a heat exchange channel that directly contacts the semiconductor device. 3. The semiconductor pellet is mounted on a wiring board and covered with a cooling jacket that constitutes the other part of the heat exchange channel, and the circuit mounting surface or back surface of the semiconductor pellet, which is a part of the heat exchange channel, etc. 3. The semiconductor device according to claim 1, wherein the cooling jackets are connected to each other via an elastic body. 4. Circulating cooling fluid supplied from the cooling fluid supply device,
In a semiconductor device in which heat generated by circuit operation of a semiconductor pellet is dissipated from the circuit mounting surface of the semiconductor pellet or its back surface, the circuit mounting surface or back surface of the second semiconductor pellet is combined with the circuit mounting surface or back surface of the second semiconductor pellet. either of the circuit mounting surface or the back surface of the first semiconductor pellet and the circuit mounting surface or the back surface of the second semiconductor pellet opposing thereto directly contact the circulating cooling fluid. A semiconductor device comprising a part of an exchange flow path. 5. A plurality of the heat exchange channels are arranged in a direction perpendicular to the circulation direction of the circulating cooling fluid, and the circulating direction of the circulating cooling fluid in each adjacent heat exchange channel is countercurrent. Each of the semiconductor devices according to claim 1 is characterized by: 6. Each of the semiconductor devices according to claim 1, wherein the circulating cooling fluid uses water.