JP2005302882A - Semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively provide a semiconductor device that cools a semiconductor chip 2a which is a heating element with low thermal resistance and, at the same time, can prevent the leakage of a cooling medium. <P>SOLUTION: The semiconductor device has a base plate 1 having a first main surface 15a and a second main surface 15b facing the first main surface 15a, a semiconductor chip 2a bonded to the first main surface 15a, and a heat sink 8 on which the semiconductor chip 2a is mounted. The heat sink 8 has a main body section 3 having a joint surface 16 bonded to the second main surface 15b and a pressing section 4 arranged in the outer peripheral portion of the first main surface 15a. The main body section 3 and pressing section 4 hold the base plate 1 in between and a first opening 9 is formed in the joint surface 16 correspondingly to the position of the semiconductor chip 2a. The cooling medium flowing through a cooling medium room 11 surrounded by the inside of the main body section 3 and the second main surface 15b exposed from the first opening 9 directly comes into contact with the second main surface 15b through the first opening 9. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a semiconductor device, and more particularly to a semiconductor device having a semiconductor chip as a heating element and a heat sink on which the semiconductor chip is mounted.

2. Description of the Related Art Conventionally, there is known a semiconductor device in which a semiconductor chip on which a semiconductor element is formed is disposed on a heat sink, and the heat generated by the semiconductor chip is cooled by the heat sink (for example, see Patent Document 1). The heat sink (heating element cooling device) disclosed in Patent Document 1 is provided with a partition plate having an opening therein. When the coolant flowing through the heat sink passes through the opening, the jet of coolant directly collides with the back surface of the heat sink corresponding to the position where the semiconductor chip is disposed. Thereby, highly efficient cooling of the semiconductor chip which is a heat generating body is attained.
JP 2002-237691

  However, when the semiconductor chip is actually mounted on the heat sink, it is difficult to mount the semiconductor chip directly on the main surface of the heat sink by soldering or the like as shown in FIG. As an example of a general mounting method, a semiconductor chip is mechanically fixed to a flat plate such as a ceramic substrate by soldering or the like, and electrical connection with an electrode pad on the surface of the semiconductor chip is performed in advance using a bonding wire or a bump. After that, there is a method of mounting this ceramic substrate on the heat sink main surface through silicon grease or the like. That is, in reality, it is common to have a laminated structure in which a ceramic substrate is mounted on the main surface of the heat sink via silicon grease, etc., and a semiconductor element is mounted on the ceramic substrate via solder. Therefore, the thermal resistance between the heat sink and the semiconductor chip is large, and efficient cooling is difficult.

  In addition, since the internal structure of the heat sink having an opening through which the coolant passes is complicated, it is difficult to mold it as an integral structure. It is practical to divide the heat sink into several components and join them to form the entire heat sink. That is, the entire heat sink is formed by joining the bottom plate of the heat sink, the partition plate having the apertures, and the top plate using methods such as soldering, brazing, welding, and bonding using the side plates. The upper surface plate and the side surface plate, or the lower surface plate and the side surface plate can be respectively molded as an integral structure.

  Therefore, the following problems occur due to the above-described realistic structure.

  First, the structure of the heat sink is complicated, and costs such as processing costs increase. In particular, when a partition plate having an opening is provided inside the heat sink, the internal structure of the heat sink becomes complicated and the cost rises significantly. Further, it may be difficult to integrally mold the entire heat sink by pouring, for example, aluminum into a mold. As a result, it is necessary to perform necessary processing on a plurality of metal plates and join them to form an integrated heat sink, which further increases the cost.

  Second, in order to cool the semiconductor chip more efficiently, it is effective to cause the jet of the coolant to directly collide with the back surface of the ceramic substrate on which the semiconductor chip is mounted without using silicon grease having a relatively large thermal resistance. It is considered to be appropriate. However, when directly bonding the ceramic substrate to the upper surface of the heat sink using a low thermal resistance bonding material such as soldering, the temperature rise condition required in the soldering process is not possible because the inside of the heat sink is hollow or the back side of the upper surface of the heat sink is not necessarily flat. It is difficult to obtain and difficult to realize.

  A feature of the present invention is that a base plate having a first main surface and a second main surface opposite to the first main surface, a semiconductor chip bonded to the first main surface, and the semiconductor chip are mounted. A heat sink includes a main body having a bonding surface bonded to a second main surface of the base plate, and a pressing portion disposed on an outer peripheral portion of the first main surface of the base plate. The main body portion and the pressing portion sandwich the base plate, and a first opening portion is formed on the bonding surface of the main body portion corresponding to the position where the semiconductor chip is disposed, The refrigerant flowing through the refrigerant chamber defined by the region surrounded by the second main surface of the base plate exposed from the opening portion directly contacts the second main surface of the base plate through the first opening portion. The gist is to do.

  ADVANTAGE OF THE INVENTION According to this invention, the semiconductor device which prevents the leakage of a refrigerant | coolant at the same time it cools the semiconductor chip which is a heat generating body with low thermal resistance can be provided at low cost.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

(First embodiment)
In the first to fifth embodiments of the present invention, as an example of a device having a heating element and a heat sink that cools the heat generated from the heating element, the semiconductor chip on which the semiconductor element is formed and the heat generated from the semiconductor chip are generated. A semiconductor device including a heat sink for cooling will be described.

  As shown in FIG. 1, the semiconductor device according to the first embodiment of the present invention is arranged at a central portion of a base plate 1 composed of a ceramic substrate or a laminated substrate in which a ceramic substrate and a metal material are laminated, and the base plate 1. A plurality of semiconductor chips (for example, first to third semiconductor chips) 2a to 2c and a holding portion 4 disposed on the outer peripheral portion of the base plate 1 so as to surround the outer periphery of the first to third semiconductor chips 2a to 2c. And have.

  As shown in FIG. 2, the semiconductor device of FIG. 1 includes a base plate 1 having a first main surface 15 a and a second main surface 15 b facing the first main surface 15 a at the AA ′ cut surface. It has the 1st semiconductor chip 2a joined to the 1st main surface 15a of the baseplate 1, and the heat sink 8 which pinches | interposes the outer peripheral part of the 1st and 2nd main surfaces 15a and 15b.

  The heat sink 8 includes a main body portion 3 having a joint surface 16 joined to the second main surface 15 b of the base plate 1, a pressing portion 4 disposed on the outer peripheral portion of the base plate 1, and the base plate 1 inside the main body portion 3. The partition plate 5 arranged in parallel, the main body protrusion 6 disposed on the joint surface 16 of the main body 3, and the pressing protrusion 7 disposed on the surface of the pressing portion 4 in contact with the base plate 1 are provided.

  A first opening 9 is formed on the bonding surface 16 of the main body 3 corresponding to the position where the first semiconductor chip 2a is disposed. A region surrounded by the inside of the main body 3 and the second main surface 15b of the base plate 1 exposed from the first opening 9 cools heat generated from the first to third semiconductor chips 2a to 2c. It is defined as “refrigerant chamber 11” through which refrigerant flows. Therefore, the refrigerant flowing through the refrigerant chamber 11 comes into direct contact with the second main surface 15 b of the base plate 1 through the first opening 9.

  The base plate 1 is sandwiched between the main body protrusion 6 and the pressing protrusion 7. A space surrounded by the main body 3, the pressing portion 4, the main body protruding portion 6 and the pressing protruding portion 7 is filled with a filler 14 such as an adhesive without a gap. The pressing portion 4, the base plate 1, and the main body portion 3 are bonded and joined with a filler 14 without a gap. In addition, soldering, welding, or the like may be used for joining the main body portion 3 and the pressing portion 4.

  The partition plate 5 has a second opening portion 10 corresponding to the position where the first semiconductor chip 2a is disposed. The refrigerant chamber 11 is divided into a first refrigerant chamber 12 and a second refrigerant chamber 13 located on the base plate 1 side with the partition plate 5 as a boundary.

  It is desirable that at least one of the main body portion 3 and the pressing portion 4 is formed from a resin material. Further, it is desirable that the main body protrusion 6 is made of a material softer than the main body 3. Furthermore, it is desirable that the pressing projection 7 is made of a material that is softer than the pressing portion 4.

  As shown in FIG. 3, the first to third semiconductor chips 2 a to 2 c are arranged on the first main surface 15 a of the base plate 1 at the B-B ′ cut surface of FIG. 1. A first opening 9 is formed on the bonding surface 16 of the main body 3 corresponding to the position where the first to third semiconductor chips 2a to 2c are disposed. The partition plate 5 has three second opening portions 10 corresponding to positions where the first to third semiconductor chips 2a to 2c are arranged.

  A refrigerant inflow hole 17 for allowing the refrigerant to flow into the refrigerant chamber 11 is disposed in a part of the second refrigerant chamber 13, and a refrigerant outflow hole 18 for allowing the refrigerant to flow out of the refrigerant chamber 11 is provided in the first refrigerant chamber 11. Arranged in a part of the refrigerant chamber 12. The refrigerant flows into the second refrigerant chamber 13 from the refrigerant inflow hole 17, flows from the second refrigerant chamber 13 to the first refrigerant chamber 12 through the second opening 10, and flows out from the refrigerant outflow hole 18. To do. When passing through the second opening 10 and flowing from the second refrigerant chamber 13 to the first refrigerant chamber 12, the jet of the refrigerant passes through the first opening 9 and the second main surface of the base plate 1. Collide directly with 15b.

  Next, a method for manufacturing the semiconductor device shown in FIGS. 1 to 3 will be described with reference to each of FIGS.

  (A) First, a main body protrusion 6 shown in FIG. 4A and an upper surface plate 3a of the main body 3 shown in FIG. 4B are prepared. As shown in FIG. 4C, the main body protrusion 6 is prepared. And the upper surface plate 3a are joined together by, for example, an adhesive or heat welding. In the same manner, the pressing projection 7 and the pressing portion 4 are prepared, and both are bonded by, for example, an adhesive or heat welding.

  (B) A combination of the main body projection 6 and the upper surface plate 3a shown in FIG. 5A, a partition plate 5 shown in FIG. 5B, and a lower side plate 3b of the main body 3 shown in FIG. 5C. And the joined body of the main body protruding portion 6 and the upper surface plate 3a, the partition plate 5 and the lower side surface plate 3b are joined together by, for example, an adhesive or heat welding as shown in FIG. The partition plate 5 is disposed inside the main body 3, and the main body protrusion 6 is disposed on the joint surface 16 of the main body 3.

  (C) As shown in FIG. 6A, the first to third semiconductor chips 2 a to 2 c are mounted on the first main surface 15 a of the base plate 1. Specifically, the first to third semiconductor chips 2a to 2c are mechanically fixed to the first main surface 15a by soldering or the like. Then, electrical connection with the electrode pads on the surfaces of the first to third semiconductor chips 2a to 2c is performed using bonding wires or the like as necessary.

  (D) As shown in FIG. 6 (b), the second main surface 15b of the base plate 1 of FIG. 6 (a) is placed on the joint surface 16 of the main body 3 of FIG. 5 (d). . At this time, the main body protrusion 6 is disposed between the joint surface 16 and the second main surface 15b. In addition, the base plate 1 is placed so that the first opening 9 of the main body 3 and the position where the first to third semiconductor chips 2a to 2c are arranged overlap. A refrigerant chamber 11 surrounded by the inside of the main body 3 and the second main surface 15b of the base plate 1 exposed from the first opening 9 is formed, and the refrigerant chamber 11 is defined by the partition plate 5 as the first refrigerant. It is divided into a chamber 12 and a second refrigerant chamber 13.

  (E) Finally, as shown in FIG. 6C, the pressing portion 4 is placed on the outer peripheral portion of the base plate 1 from the first main surface 15 a side of the base plate 1. At this time, the pressing protrusion 7 is disposed between the first main surface 15 a of the base plate 1 and the pressing portion 4. In this way, the base plate 1 is sandwiched between the main body 3 and the pressing portion 4 from both surfaces 15a and 15b. In this state, the space surrounded by the main body 3, the pressing portion 4, the main body protruding portion 6 and the pressing protruding portion 7 is filled with the filler 14 without any gap, and the holding portion 4, the base plate 1 and the main body 3 are bonded. Join. The semiconductor device shown in FIGS. 1 to 3 is completed through the above steps.

  As described above, according to the first embodiment of the present invention, it is surrounded by the inside of the main body 3 and the second main surface 15b of the base plate 1 exposed from the first opening 9. The region is defined as the refrigerant chamber 11, and the refrigerant flowing through the refrigerant chamber 11 comes into direct contact with the second main surface 15 b of the base plate 1 through the first opening 9. Therefore, the first to third semiconductor chips 2a to 2c, which are heating elements, can be cooled with low thermal resistance. That is, heat generated in the first to third semiconductor chips 2a to 2c can be transferred to the refrigerant without passing through a portion having a relatively large thermal resistance such as conventional silicon grease.

  In addition, by sandwiching the outer peripheral portion of the base plate 1 between the pressing portion 4 and the main body portion 3, the pressing portion 4 and the main body portion 3 are separate structures while preventing leakage of the refrigerant, so that both of them can be easily molded. I can do it.

  Further, the refrigerant flows from the second refrigerant chamber 13 through the second opening 10 to the first refrigerant chamber 12, whereby the refrigerant jet flows through the first opening 9 and the second plate of the base plate 1. It directly collides with the main surface 15b. Therefore, the first to third semiconductor chips 2a to 2c on the base plate 1 can be efficiently cooled.

  Furthermore, when the main body portion 3 and the pressing portion 4 are formed of a resin material, these material costs can be reduced, and even if both shapes are complicated, they can be easily molded at a low cost. In addition, since the resin material is generally an insulator, the electric power of the first to third semiconductor chips 2a to 2c is also present in this structure in which the base plate 1 or the wiring region on the base plate 1 can be in contact with a part of the heat sink 8. Can be easily achieved.

  Further, a main body protrusion 6 and a pressing protrusion 7 are disposed between the main body 3 and the base plate 1 and between the pressing part 4 and the base plate 1, respectively. By sandwiching, the main body protruding portion 6 and the pressing protruding portion 7 can function as an O-ring, and the above-described refrigerant leakage preventing effect can be further enhanced. Here, “O-ring-like action” means that either one of the main body protrusion 6 and the pressing protrusion 7 and the base plate is deformed, and one of them is deformed to increase the degree of adhesion between them. Refers to action. An outline of the reason why the O-ring-like action occurs will be described with reference to FIG. The pressure of the refrigerant, for example, if the refrigerant is water, the water pressure is applied to the back surface side of the joint surface 16 of the main body 3 and the second main surface 15 b of the base plate 1. As a result, the main body protrusion 6 is pressed against the second main surface 15 b of the base plate 1, and the first main surface 15 a of the base plate 1 is pressed against the pressing protrusion 7. The pressing pressure concentrates on the tip portions of the projections 6 and 7 having a small area. For example, the tip portions of the projections 6 and 7 cause some crushing deformation, thereby further improving the refrigerant leakage prevention function. Therefore, there is no need for a large space by high-density screwing to apply pressure uniformly to the O-ring itself and the width of the O-ring itself, as in the case of using a conventional O-ring, and the device can be downsized. It is.

  Further, since the outer peripheral portions of the main body 3, the presser 4, and the base plate 1 are adhesively bonded with a filler 14 such as an adhesive without gaps, the leakage of the refrigerant is coupled with the O-ring action of the protrusions 6 and 7 described above. The prevention effect is improved. In general, it is easy for the resin material and the adhesive to exhibit high adhesive strength. Therefore, when the main body part 3 and the pressing part 4 are formed of a resin material, the above-described refrigerant leakage prevention effect becomes even more remarkable.

  Furthermore, as shown in FIGS. 4 and 5, when the main body 3 or the main body 3 and the partition plate 5 are formed by laminating a plurality of plate members, the main body 3 and the partition plate 5 have a complicated shape. Even so, it can be formed at low cost. In particular, if a resin material is used as the plate material of the main body 3 and the partition plate 5, each member can be easily molded, and each member can be easily laminated and bonded by heat welding or adhesion. As shown in FIGS. 4 and 5, in the first embodiment, a combined body of the main body 3 and the partition plate 5 is formed by laminating and joining a plurality of plate members 3 a, 3 b, and 5. Although the case has been described, the present invention is not limited to this. For example, the main body part 3 or the main body part 3 and the partition plate 5 may be an integral structure integrally molded. If the main body 3 or the main body 3 and the partition plate 5 are formed as an integral structure, the number of parts can be reduced and the cost can be reduced.

  Further, by forming the main body protrusion 6 from the main body 3 with a soft material and forming the pressing protrusion 7 from the pressing portion 4 with a soft material, the following effects are produced. That is, the main body part 3 and the pressing part 4 themselves are made of a hard material to increase the mechanical strength, and can be reliably prevented from being deformed even when a refrigerant pressure is applied. Further, the main body protrusion 6 and the pressing protrusion 7 are made of a soft material, and the refrigerant pressure is more reliably reduced by concentrating and crushing the load due to the pressure of the refrigerant on the tip of the main body protrusion 6 and the pressing protrusion 7. Leakage can be prevented. In particular, when a resin material is used as the constituent material of the main body 3, the pressing portion 4, and the protrusions 6 and 7, the structure is formed between the main body 3 and the pressing portion 4 and the protrusions 6 and 7. The above effect can be easily obtained by changing the material, and it is possible to easily join even the different materials of the main body 3 and the pressing portion 4 and the protrusions 6 and 7.

  Furthermore, in the first embodiment of the present invention, the case where the base plate 1 is formed of a ceramic substrate or a laminated member of a ceramic substrate and a metal member has been described. In this case, even in the structure in which the first to third semiconductor chips 2a to 2c are mounted on the ceramic substrate for electrical insulation and wiring area formation, the coolant can be directly brought into contact with the back surface of the ceramic substrate. The first to third semiconductor chips 2a to 2c can be cooled with sufficiently low thermal resistance. In addition, since it is not necessary to provide a separate material such as a base plate made of a metal plate on the back surface of the ceramic substrate, the laminated structure is simplified, thereby reducing thermal resistance and cost. At the same time, since the ceramic substrate and the main body 3 of the heat sink 8 are not joined by a rigid material such as solder, reliability is improved due to thermal stress due to a difference in thermal expansion coefficient between different materials (ceramic substrate and main body 3). It is also possible to avoid this problem.

  In the heating element cooling device disclosed in Patent Document 1 shown in the background art section, the semiconductor chip is mounted on the ceramic substrate, the upper surface of the heat sink is opened, and the back surface of the ceramic substrate is in direct contact with the refrigerant. When configured, it is difficult to take a structural measure for preventing refrigerant leakage at the bonding interface between the heat sink opening and the ceramic substrate. When bonded by bonding, soldering or welding, the ceramic substrate and the metal material constituting the heat sink generally have different thermal expansion coefficients, and there is a concern about reliability due to thermal stress. Furthermore, since the pressure of the refrigerant acts in the direction to peel off the joint, the possibility of refrigerant leakage cannot be denied in combination with the above-mentioned reliability concerns. In addition, there is a problem that the semiconductor chip is damaged by a high temperature process when soldering or welding the ceramic substrate on which the semiconductor chip is mounted, or that it is difficult to raise the temperature to a necessary temperature. On the other hand, according to the semiconductor device according to the first embodiment of the present invention, as described above, the bonding reliability between the base plate 1 and the heat sink 8 is high, and it is possible to more reliably prevent refrigerant leakage. I can do it.

(Second Embodiment)
As shown in FIG. 8, the semiconductor device according to the second embodiment of the present invention includes a base plate 1 made of a metal plate, and first to third semiconductor chips 2a to 2c arranged in the central portion of the base plate 1. And a pressing portion 4 disposed on the outer peripheral portion of the base plate 1 so as to surround the outer periphery of the first to third semiconductor chips 2a to 2c. The pressing portion 4 includes a first pressing portion 4 a disposed on the three sides of the outer peripheral portion of the base plate 1 and a second pressing portion 4 b disposed on the remaining one side of the outer peripheral portion of the base plate 1. .

  Note that the cross-sectional structure of the semiconductor device according to the second embodiment is the same as the cross-sectional structure of the semiconductor device shown in FIGS. The first pressing portions 4 a are arranged on the three sides of the outer peripheral portion of the base plate 1. The second pressing portion 4 b is disposed on the remaining one side of the outer peripheral portion of the base plate 1. Other components are the same as those of the semiconductor device shown in FIGS.

  A part of the manufacturing process of the semiconductor device of FIG. 8 will be described with reference to FIG. In the first embodiment, as shown in FIG. 6, after the base plate 1 is placed on the main body portion 3, the outer peripheral portion of the base plate 1 is sandwiched between the pressing portions 4. On the other hand, in the manufacturing process of the semiconductor device of FIG. 8, the first pressing portion 4a is joined to the main body 3 in advance before the base plate 1 is placed on the main body 3 as shown in FIG. Alternatively, the main body portion 3 and the first pressing portion 4a are molded as an integral structure. Thereafter, the base plate 1 on which the first to third semiconductor chips 2a to 2c are mounted is inserted from the remaining one side of the outer peripheral portion of the base plate 1 while the main body 3 and the first pressing portion 4a face each other. To do. Before the base plate 1 is inserted, an adhesive as a filler 14 is applied in advance while the main body 3 and the first pressing portion 4a are opposed to each other. After the base plate 1 is inserted, the remaining one side of the outer peripheral portion of the base plate 1 is sandwiched between the second pressing portions 4b.

  Other manufacturing processes are the same as those of the semiconductor device of the first embodiment, and the description and illustration are omitted.

  As described above, according to the second embodiment of the present invention, the first pressing portion 4a and the main body portion 3 are joined in advance on the three sides of the outer peripheral portion of the base plate 1, so that the refrigerant There is no fear of leakage, and a sufficiently high bonding strength can be ensured. The remaining one side of the outer peripheral portion of the base plate 1 also leaks refrigerant such as filling the space surrounded by the main body 3, the second pressing portion 4 b, the main body protruding portion 6 and the pressing protruding portion 6 with the filler 14. It is sufficient to take preventive measures. The load of the refrigerant pressure applied to the remaining one side may also be reduced, and the formation of the refrigerant leakage prevention structure is further facilitated. In particular, as described above, when the resin material is used for the main body 3 or the main body 3 and the first and second pressing portions 4a and 4b, the first pressing portion 4a and the main body 3 are made of the same structure. It is possible to easily perform the bonding or as a laminated combination.

(Third embodiment)
As shown in FIG. 10, the semiconductor device according to the third embodiment of the present invention includes a base plate 1 made of a metal plate and first to third semiconductor chips 2 a to 2 c arranged at a central portion of the base plate 1. And a pressing portion 4 disposed on the outer peripheral portion of the base plate 1 so as to surround the outer periphery of the first to third semiconductor chips 2a to 2c. The pressing portion 4 is adjacent to the first pressing portion 4a disposed on the three sides of the outer peripheral portion of the base plate 1 and the second pressing portion 4b disposed on the remaining one side of the outer peripheral portion of the base plate 1. A third pressing portion 4c disposed between the first and second semiconductor chips 2a and 2b, and a fourth pressing portion disposed between the adjacent second and third semiconductor chips 2b and 2c. 4d.

  As shown in FIG. 11, the first to third semiconductor chips 2 a to 2 c are arranged on the first main surface 15 a of the base plate 1 at the C-C ′ cut surface of FIG. 10. Three first hole portions 9 are formed on the bonding surface 16 of the main body portion 3 corresponding to the positions where the first to third semiconductor chips 2a to 2c are disposed. The partition plate 5 has three second opening portions 10 corresponding to positions where the first to third semiconductor chips 2a to 2c are arranged.

  A refrigerant inflow hole 17 for allowing the refrigerant to flow into the refrigerant chamber 11 is disposed in a part of the second refrigerant chamber 13, and a refrigerant outflow hole 18 for allowing the refrigerant to flow out of the refrigerant chamber 11 is provided in the first refrigerant chamber 11. Arranged in a part of the refrigerant chamber 12. The refrigerant flows into the second refrigerant chamber 13 from the refrigerant inflow hole 17, flows from the second refrigerant chamber 13 to the first refrigerant chamber 12 through the second opening 10, and flows out from the refrigerant outflow hole 18. To do. When passing through the second opening 10 and flowing from the second refrigerant chamber 13 to the first refrigerant chamber 12, the jet of the refrigerant passes through the first opening 9 and the second main surface of the base plate 1. Collide directly with 15b.

  The third pressing portion 4c and the pressing protrusion 7 are disposed between the adjacent first and second semiconductor chips 2a and 2b, and the fourth pressing portion 4d and the pressing protrusion 7 are adjacent to the second and second semiconductor chips 2a and 2b. Arranged between the third semiconductor chips 2b and 2c. The main body 3 and the main body protrusion 6 are also arranged between the adjacent first and second semiconductor chips 2a and 2b and between the adjacent second and third semiconductor chips 2b and 2c, respectively. Yes. The third and fourth pressing portions 4c and 4d and the main body 3 sandwich the base plate 1 between the adjacent semiconductor chips 2a to 2c.

  Note that the cross-sectional structure corresponding to FIG. 2 of the semiconductor device according to the third embodiment is the same as the cross-sectional structure of the semiconductor device shown in FIG.

  As described above, according to the third embodiment of the present invention, the size of the base plate 1 is increased by mounting the plurality of semiconductor chips 2 a to 2 c on the base plate 1, thereby adding to the base plate 1. Even when the refrigerant pressure load increases, the base plate 1 can be reliably fixed, and refrigerant leakage can be prevented more reliably.

(Fourth embodiment)
FIG. 12 is a cross-sectional view showing a semiconductor device according to the fourth embodiment of the present invention, which corresponds to FIG. As shown in FIG. 12, in the semiconductor device according to the fourth embodiment of the present invention, the end portion of the holding portion 24 has a U-shaped shape, and the side surface of the main body portion 3 has a U-shaped shape. It is plugged inside. Other cross-sectional structures are the same as those of the semiconductor device shown in FIG.

  Note that the planar structure and the sectional structure of the semiconductor device according to the fourth embodiment are the same as the planar structure and the sectional structure of the semiconductor device shown in FIGS.

  As described above, according to the fourth embodiment of the present invention, since the pressing portion 24 can be more firmly coupled to the main body portion 3, the refrigerant pressure is applied to the second main surface 15 b of the base plate 1. Even if the load is applied, it is possible to prevent the refrigerant leakage more reliably. As described above, when a resin material is used for the pressing portion 24, the end portion of the pressing portion 24 can be easily stretched into a U-shape.

(Fifth embodiment)
FIG. 13 is a cross-sectional view showing a semiconductor device according to the fifth embodiment of the present invention, which corresponds to FIG. As shown in FIG. 13, in the semiconductor device according to the fifth embodiment of the present invention, a module 25 as a sealed body in which a semiconductor chip is sealed with a mold resin on the first main surface 15a side of the base plate 1 is provided. The main body 3 and the pressing part 26 sandwich the base plate 1 and the module 25. Further, the end portion of the pressing portion 26 has a U-shaped shape, and the side surfaces of the module 25, the base plate 1 and the main body portion 3 are inserted into the U-shaped shape. Other cross-sectional structures are the same as those of the semiconductor device shown in FIG.

  As described above, according to the fifth embodiment of the present invention, even if a sealed module body is disposed on the first main surface 15a side of the base plate 1 in advance, for example, like a power module, The same effects as those shown in the first to fourth embodiments can be obtained. Furthermore, in general, power modules are industrially produced in large quantities and can be expected to be low in cost. That is, semiconductor devices (for example, power modules) that can easily achieve low cost and have low thermal resistance due to industrial mass production effects. Can be produced at low cost.

(Modification of the fifth embodiment)
As shown in FIG. 14, the semiconductor device according to the modification of the fifth embodiment of the present invention is a fixed component (for example, screw) that presses and joins the pressing portion 26, the main body portion 3, the base plate 1, and the module 25. 27. The other cross-sectional structure is the same as the cross-sectional structure of the semiconductor device shown in FIG.

  As described above, according to the modification of the fifth embodiment of the present invention, the refrigerant water pressure is applied to the second main surface 15b of the base plate 1 in addition to the effects of the fifth embodiment described above. However, it is possible to prevent refrigerant leakage more reliably. The refrigerant leakage prevention mechanism is realized by the filler 14 in addition to the main body 3 and the pressing portion 26 or the end portions of the main body 3 and the pressing portion 26 and the sandwiched portion (outer peripheral portion) of the base plate 1. Yes. Therefore, it is not always necessary to provide a large number of fixing parts such as the screws 27 at short intervals, and it becomes possible not to hinder the integration / miniaturization of the entire apparatus.

(Other embodiments)
As described above, the present invention has been described with reference to the first to fifth embodiments and modifications thereof. However, it should be understood that the description and drawings constituting a part of this disclosure limit the present invention. is not. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  In the second to fifth embodiments and modifications thereof, the case where the base plate 1 is made of a metal plate has been described. However, the present invention is not limited to this, and the base plate 1 may be formed of a ceramic substrate or a laminated member of a ceramic substrate and a metal material, as in the first embodiment. In this case, the following effects are produced in addition to the effects of the respective embodiments. That is, even when the first to third semiconductor chips 2a to 2c are mounted on the ceramic substrate for electrical insulation and wiring area formation, the refrigerant is directly applied to the back surface (second main surface 15b) of the ceramic substrate. Since they are in contact with each other, the first to third semiconductor chips 2a to 2c can be cooled with sufficiently low thermal resistance. Further, since it is not necessary to provide another material such as a base plate made of a metal plate on the back surface of the ceramic substrate, the laminated structure can be simplified, and the thermal resistance and cost can be reduced. Furthermore, since it is not necessary to join the ceramic substrate and the main body 3 of the heat sink 8 with a rigid material such as solder, it is possible to avoid the occurrence of reliability problems due to thermal stress due to the difference in thermal expansion coefficient between different materials. Is possible.

  Thus, it should be understood that the present invention includes various embodiments and the like not described herein. Therefore, the present invention is limited only by the invention specifying matters according to the scope of claims reasonable from this disclosure.

  As described above, according to the first to fifth embodiments of the present invention, a semiconductor device can be configured using an inexpensive material such as a resin with a structure that can be easily manufactured, and therefore, the cost can be easily reduced. In addition, cooling with low thermal resistance can be performed without giving reliability concerns to the ceramic substrate on which the semiconductor chip is mounted. Furthermore, even in the structure in which the refrigerant is in direct contact with the back surface of the ceramic substrate corresponding to the position where the semiconductor chip is mounted, it is possible to reliably prevent the refrigerant from leaking and to cope with the thermal stress due to the difference in the thermal expansion coefficient of the constituent materials. There are no reliability concerns. Furthermore, it is easy to use a power module that is likely to reduce the cost.

  INDUSTRIAL APPLICABILITY The present invention can be used industrially as an inverter device provided to drive an AC motor such as an electric vehicle motor.

1 is a plan view showing a semiconductor device according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line A-A ′ of the semiconductor device of FIG. 1. FIG. 2 is a cross-sectional view taken along a B-B ′ cut surface of the semiconductor device of FIG. 1. 4A shows the main body protrusion, FIG. 4B shows the upper surface plate of the main body, and FIG. 4C is a cross-sectional view showing a state where the main body protrusion and the upper surface plate are joined. FIG. 5A shows a combination of the main body protrusion and the upper surface plate, FIG. 5B shows a partition plate, FIG. 5C shows the lower side plate of the main body portion, and FIG. It is sectional drawing which shows the laminated body of a main-body part, a partition plate, and a main-body projection part. FIG. 6A shows the stacked combination of the first semiconductor chip and the base plate, and FIG. 6B shows the stacked combination of FIG. 6A placed on the stacked combination of FIG. 5D. It is sectional drawing which shows the state which carried out. It is a figure for demonstrating a part of effect produced by the semiconductor device concerning the 1st Embodiment of this invention. It is a top view which shows the semiconductor device concerning the 2nd Embodiment of this invention. FIG. 9 is a process plan view showing a part of the manufacturing process for the semiconductor device in FIG. 8; It is a top view which shows the semiconductor device concerning the 3rd Embodiment of this invention. FIG. 11 is a cross-sectional view taken along the line C-C ′ of the semiconductor device of FIG. 10. It is sectional drawing which shows the semiconductor device concerning the 4th Embodiment of this invention. It is sectional drawing which shows the semiconductor device concerning the 5th Embodiment of this invention. It is sectional drawing which shows the semiconductor device concerning the modification of the 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base plate 2a ... 1st semiconductor chip 2b ... 2nd semiconductor chip 2c ... 3rd semiconductor chip 3 ... Main-body part 3a ... Upper surface board 3b ... Lower side surface board 4, 24, 26 ... Press part 4a ... 1st Presser 4b ... Second presser 4c ... Third presser 4d ... Fourth presser 5 ... Partition plate 6 ... Main body protrusion 7 ... Presser protrusion 8 ... Heat sink 9 ... First aperture 10 ... 2nd opening part 11 ... Refrigerant chamber 12 ... 1st refrigerant chamber 13 ... 2nd refrigerant chamber 14 ... Filler 15a ... 1st main surface 15b ... 2nd main surface 16 ... Joining surface 17 ... Refrigerant inflow Hole 18 ... Refrigerant outflow hole 25 ... Module 27 ... Screw

Claims (16)

A base plate having a first main surface and a second main surface opposite to the first main surface;
A semiconductor chip bonded to the first main surface;
A main body having a joint surface joined to the second main surface; and a pressing portion disposed on an outer peripheral portion of the first main surface, the main body and the pressing portion sandwiching the base plate A heat sink,
A first opening is formed in the joint surface corresponding to the position where the semiconductor chip is disposed, and the second main body exposed from the inside of the main body and the first opening. A semiconductor device characterized in that a refrigerant flowing through a refrigerant chamber defined by a region surrounded by a surface is in direct contact with the second main surface through the first opening.   The heat sink further includes a partition plate disposed in parallel to the base plate in the main body, and the partition plate has a second opening corresponding to a position where the semiconductor chip is disposed. And the refrigerant chamber is divided into a first refrigerant chamber and a second refrigerant chamber located on the base plate side with the partition plate as a boundary, and the refrigerant is separated from the second refrigerant chamber to the second refrigerant chamber. 2. The semiconductor device according to claim 1, wherein the semiconductor device collides with the second main surface through the first opening by flowing into the first refrigerant chamber through the opening.   3. The semiconductor device according to claim 1, wherein at least one of the main body portion and the pressing portion is made of a resin material.   The semiconductor device according to claim 1, wherein the main body portion or the main body portion and the partition plate are an integral structure.   4. The semiconductor device according to claim 1, wherein the main body portion or the main body portion and the partition plate are formed by laminating and bonding a plurality of plate members.   The heat sink further includes a main body protrusion disposed on the joining surface and a pressing protrusion disposed on a surface of the pressing portion in contact with the base plate, and the base plate includes the main body protrusion and the pressing member. The filler is filled in a space sandwiched by the protrusions and surrounded by the main body part, the pressing part, the main body protruding part, and the pressing protrusion part. The semiconductor device described.   The semiconductor device according to claim 6, wherein the filler is an adhesive.   8. The semiconductor device according to claim 6, wherein the main body protrusion is made of a material softer than the main body.   The semiconductor device according to claim 6, wherein the pressing protrusion is made of a material softer than the pressing portion.   The pressing portion is divided into a first pressing portion disposed on the three sides of the outer peripheral portion of the base plate and a second pressing portion disposed on the remaining one side of the outer peripheral portion. The semiconductor device according to claim 1, wherein the pressing portion is joined to the main body portion in advance before sandwiching the base plate.   The semiconductor device further includes a second semiconductor chip bonded to the first main surface, and the main body portion and the pressing portion are also disposed between the semiconductor chip and the second semiconductor chip, and the base plate is The semiconductor device according to claim 1, wherein the semiconductor device is sandwiched.   The end portion of the pressing portion has a U-shaped shape, and a side surface of the main body portion is inserted into the U-shaped shape. Semiconductor device.   A module as a sealed body in which the semiconductor chip is sealed with a mold resin is disposed on the first main surface side of the base plate, and the main body portion and the pressing portion sandwich the base plate and the module. The semiconductor device according to claim 1.   The semiconductor device according to claim 1, further comprising a fixing component that press-joins the pressing portion and the main body portion.   The semiconductor device according to claim 1, wherein the base plate is a ceramic substrate or a laminated substrate in which a ceramic substrate and a metal material are laminated.   16. The semiconductor device according to claim 1, wherein the semiconductor device comprises an inverter device used for driving an AC motor as a load.