JP2007201224A - Semiconductor device - Google Patents

Abstract

A semiconductor device having a simple configuration that does not impair the downsizing of the device, and can reliably prevent problems such as short-circuiting of electrode terminals even when liquid leakage occurs from a seal portion of a semiconductor module. provide.
A semiconductor module having a semiconductor element mounted thereon and a liquid cooling member. The cooling surface of the semiconductor module faces the opening of a flow passage formed in the liquid cooling member. The periphery of the opening 21 and the periphery of the semiconductor module 1 are joined with the seal member 3 interposed therebetween. The semiconductor module 1 is located between the electrode terminals 11 and 12 and the seal member 3 and is liquid-cooled. A liquid-proof wall 4 projecting toward the outside of the side surface 19 substantially orthogonal to the joint surface with the member 2 is integrally provided.
[Selection] Figure 1

Description

  The present invention relates to a semiconductor device having a function of cooling a semiconductor module including a semiconductor element having a large calorific value, and more particularly, to a semiconductor device having a direct liquid cooling structure for directly cooling a semiconductor module with a cooling liquid. .

  In a semiconductor device that handles a large amount of power such as an inverter that drives a motor of an electric vehicle or a hybrid vehicle, a semiconductor module in which a plurality of power semiconductor elements such as an insulated gate bipolar transistor (IGBT) that consumes a large amount of power is packaged. It is used. Such a power semiconductor module has a large amount of heat generation, and thus needs to be efficiently cooled. In particular, since the power density of recent semiconductor modules for electric power has been improved, so-called direct liquid cooling, in which the semiconductor module is directly cooled with a cooling liquid to improve the cooling performance, is being increasingly adopted. In this case, since the installation space is small in the automobile, it is required to be as small as possible.

  By the way, in the conventional direct liquid cooling type, the periphery of the opening of the liquid cooling member and the periphery of the semiconductor module are arranged such that the cooling surface of the semiconductor module faces the flow passage formed in the liquid cooling member through the opening. By integrally joining the semiconductor module and the liquid cooling member with the sealing member interposed therebetween, the cooling liquid directly cools the cooling surface of the semiconductor module and the cooling liquid leaks to the outside from the flow path. This is a structure that prevents this by a seal member (see, for example, Patent Document 1). In this case, what is called a gasket or an O-ring is applied as the seal member.

  However, with such a structure, liquid leakage may occur due to non-uniform pressure applied to the seal member, biting of foreign matter due to foreign matter adhering to the seal surface, or damage or aging of the seal member. There is. And if the coolant leaks from this seal part and the electrode terminal of the semiconductor module gets wet, an electrical short circuit may occur between the electrodes, resulting in a decrease in insulation and a failure of the semiconductor module. There is a problem that the period that can be guaranteed cannot be extended.

  Therefore, in the prior art, in order to prevent the insulation between the electrode terminals from being lowered as much as possible even if the coolant leaks from the seal portion, the seal member is arranged in an inner and outer double around the opening of the liquid cooling member. Measures are taken to prevent leakage.

  However, even when such measures are taken, it is difficult to properly adjust the tightening pressures of the inner and outer double seal members independently of each other. There was a risk of causing liquid leakage through the seal member.

  Therefore, in the prior art, a leakage discharge groove for discharging the leakage and a drain hole communicating with the leakage discharge groove are formed in a portion located outside the sealing member of the cooling member, and the coolant is discharged from the sealing portion. In the case of leakage, a structure has been proposed in which this cooling liquid is guided to the outside of the apparatus via a liquid discharge groove and a liquid drain hole to prevent a short circuit between electrode terminals (for example, a patent) Reference 2-4 etc.).

JP-A-9-246443 JP 2001-308246 A JP 2003-31745 A JP 2005-32904 A

  However, in the case of the conventional structure described in Patent Documents 1 to 4, it is necessary to form a liquid discharge groove and a liquid drain hole in the liquid cooling member, and the liquid discharge groove is closed at the bottom of the semiconductor module. The shape of the semiconductor module must be increased so as to be tubular, and the overall shape of the device is increased, which hinders downsizing. Therefore, particularly when the installation space is narrow and limited as in an automobile, it is not possible to sufficiently meet the demand for downsizing.

  In addition, since it is necessary to perform a cutting process such as forming a liquid discharge groove or a liquid drain hole in the liquid cooling member, the configuration becomes complicated and an extra cost is required. In addition, if the actual use environment is not good, there is a problem that the liquid leakage drain groove and the liquid drain hole are clogged with dust and the liquid cannot flow well.

  The present invention solves the above-described problems, does not impair the downsizing of the apparatus, and has a simple configuration, and even if liquid leakage occurs from the seal portion between the semiconductor module and the liquid cooling member, the electrode terminal It is an object of the present invention to provide a semiconductor device that can reliably prevent problems such as short-circuiting of parts and can be realized at a relatively low cost.

  In order to solve the above-mentioned problems, the present invention has a semiconductor module on which a semiconductor element is mounted, a flow path for cooling liquid inside, and an opening formed so that a part of the flow path is exposed to the outside. A direct liquid in which the semiconductor module and the liquid cooling member are integrally joined via a seal member, and the cooling surface of the semiconductor module faces the opening of the flow passage. The following configuration is employed in the cold semiconductor device.

  That is, according to the present invention, the semiconductor module includes a liquidproofing member that is located between the electrode terminal and the sealing member and that protrudes outward from the side surface substantially orthogonal to the bonding surface with the liquid cooling member. It is characterized in that the wall is provided integrally.

  According to the semiconductor device of the present invention, the semiconductor module includes a liquid-proof solution projecting outward from the side surface substantially orthogonal to the bonding surface with the liquid cooling member at a position located between the electrode terminal and the seal member. Since the wall is provided integrally, even if the coolant leaks from the seal part due to insufficient sealing effect by the seal member, the liquid barrier ensures that the leaked liquid flows toward the electrode terminal. Be blocked. For this reason, even when the apparatus is installed in an upright state, it is possible to reliably prevent the occurrence of a problem that the electrode terminals are electrically short-circuited due to leakage.

  In addition, unlike the prior art, it is not necessary to form a liquid discharge groove or liquid drain hole in the liquid cooling member, and it is not necessary to close the liquid discharge groove at the bottom of the semiconductor module to form a tube. The overall shape can be reduced in size. Further, it is not necessary to perform a cutting process such as forming a liquid discharge groove or a liquid drain hole in the liquid cooling member as in the prior art, and it is only necessary to form a liquid barrier on the semiconductor module. It becomes possible.

Embodiment 1 FIG.
1 is a perspective view showing a main part of a semiconductor device according to Embodiment 1 of the present invention, FIG. 2 is a sectional view of a semiconductor module constituting the device, and FIG. 3 is an enlarged sectional view showing a part of the device. FIG. 4 is an operation explanatory view of a liquid barrier provided in the semiconductor module of the apparatus.

  The semiconductor device according to the first embodiment includes a semiconductor module 1 and a liquid cooling member 2. In the semiconductor module 1, a power supply electrode terminal 11 is drawn out from one side of a side surface 19 of a rectangular parallelepiped body 10, and a control signal electrode terminal 12 for switching control is drawn out from the other side. .

  In addition, a plurality of power switching elements 13 such as IGBTs are fixed to the heat spreader 14 made of a copper plate or the like as semiconductor elements by soldering or the like inside the main body 10, and between the switching elements 13. The electrode terminals 11 and 12 are electrically connected by wire bonding with a thin metal wire 15 such as an aluminum wire. Further, a module base 17 made of a material such as copper, which has good thermal conductivity and hardly corrodes, is disposed on the back side of the heat spreader 14 via an insulating layer 16. Then, in order to protect the switching element 13 and the fine metal wire 15 from the outside environment, the whole except the bottom surface that releases heat from the module base 17 to the outside is molded with the sealing resin 18. The module base 17 efficiently transmits heat generated from the switching element 13 to the outside, and at the same time plays a role of reliably sealing a seal member 3 described later.

  On the other hand, the liquid cooling member 2 is made of a metal such as copper or aluminum, or a resin such as PPS (polyphenylene sulfide), and a coolant flow passage 20 is formed therein, and one of the flow passages 20 is formed. The opening portion 21 is provided by being deleted so that the portion is exposed to the outside. In addition, a mounting groove 22 for mounting a seal member 3 such as an O-ring is formed in the peripheral portion of the opening 21.

  Then, the semiconductor module 1 and the liquid cooling are mounted in a state where the sealing member 3 is mounted in the mounting groove 22 so that the module base 17 serving as a cooling surface of the semiconductor module 1 faces the opening 21 of the flow passage 20 of the liquid cooling member 2. The member 2 is aligned, and both 1 and 2 are fastened by bolts or the like (not shown). Then, by flowing a cooling liquid made of an aqueous solution of a highly viscous liquid such as ethylene glycol or the like through the flow passage 20 of the liquid cooling member 2, the switching element 13 constituting the semiconductor module 1 is connected to the cooling liquid via the module base 17 or the like. The coolant is directly cooled by the seal member 3 and is sealed by the seal member 3 so that the coolant does not leak from the flow passage 20 to the outside.

  Further, as a feature of the first embodiment, the main body 10 of the semiconductor module 1 has a liquidproofing at a position located between the electrode terminals 11 and 12 and the seal member 3 on the protruding side of the electrode terminals 11 and 12. The wall 4 is provided integrally.

  That is, the liquid barrier 4 has one end 41 side fixed to the outer side of the seal member 3 on the bottom surface of the main body 10 of the semiconductor module 1 with an adhesive or the like, and the other end 42 side is the main body 10. The electrode terminals 11 and 12 are bent into a bowl shape in order to be bent from the state along the protruding side surface 19 to the state protruding outward along the electrode terminals 11 and 12. The tip of the other end portion 42 of the liquid barrier 4 protrudes slightly outward from the side surface 23 of the liquid cooling member 2. As the material of the liquid barrier 4, an insulating material such as a synthetic resin or ceramic is preferably used in consideration of the withstand voltage of the electrode terminals 11 and 12.

  In the above configuration, the pressure applied to the seal member 3 when the semiconductor module 1 and the liquid cooling member 2 are fastened by bolts (not shown) or the like, or foreign matter on the joint surface between the semiconductor module 1 and the liquid cooling member 2 When the coolant L leaks outside the seal member 3 due to biting or damage to the seal member 3 or deterioration over time, the leaked liquid L spreads on the liquid cooling member 2 and reaches its side surface 23. Although flowing out, since the liquid-proof wall 4 is provided in the main-body part 10 of the semiconductor module 1, the electrode terminals 11 and 12 thereabove are not wetted. Therefore, even when the apparatus is installed in a standing state, it is possible to reliably prevent the occurrence of a problem that the electrode terminals 11 and 12 are electrically short-circuited by the liquid leakage L.

  Further, the liquid cooling member 2 does not need to be formed with a liquid leakage discharge groove or a liquid drain hole as in the prior art, and it is not necessary to close the liquid leakage discharge groove at the bottom of the semiconductor module 1 to make it tubular. The shape of the entire apparatus can be reduced in size. Further, it is not necessary to perform a cutting process for forming the liquid leakage drain groove or the liquid drain hole, and it is only necessary to fix the liquid barrier wall 4 forming member to the main body portion 10 of the semiconductor module 1, so that it can be realized at a relatively low cost. It becomes possible.

  In the first embodiment, the liquid barrier 4 is formed in a bowl shape, but is not limited to such a shape. For example, the electrode terminal 11 is located from a position outside the seal member 3 on the bottom surface of the main body 10. , 12 may be a flat plate projecting in parallel. In the first embodiment, the liquid barrier 4 is provided only on the protruding side of the electrode terminals 11 and 12 of the main body 10, but it can be formed continuously around the main body 10. With this configuration, it is possible to prevent leakage of the liquid from flowing into the electrode terminals 11 and 22 from the portion without the liquid barrier 4, so that the occurrence of a short circuit between the electrode terminals 11 and 12 can be more reliably prevented.

Embodiment 2. FIG.
FIG. 5 is a cross-sectional view showing the configuration of the semiconductor device according to the second embodiment of the present invention, and the same reference numerals are given to the same or corresponding components as those of the first embodiment shown in FIGS.

  The feature of the second embodiment is that the one end portion 41 side of the liquid barrier 4 is not fixed to the bottom surface of the main body portion 10 of the semiconductor module 1 but is attached to the side surface 19 substantially orthogonal to the bottom surface of the main body portion 10 by an adhesive. It is fixed directly.

When the liquid-proof wall 4 is directly fixed to the side surface 19 of the main body 10 of the semiconductor module 1 as in the second embodiment, the liquid-proof wall 4 is fixed to the bottom surface of the main body 10. Since it is not necessary to secure a bonding space, the degree of freedom in adjusting the tightening force on the seal member 3 when the semiconductor module 1 is fastened to the liquid cooling member 2 with bolts or the like is increased, and the liquid barrier 4 is attached. Work becomes easy and workability is improved.
Since other configurations and operational effects are the same as those in the first embodiment, detailed description thereof is omitted here.

Embodiment 3 FIG.
FIG. 6 is a cross-sectional view showing the configuration of the semiconductor device according to the third embodiment of the present invention, and the same reference numerals are given to the same or corresponding components as those of the first embodiment shown in FIGS.

  A feature of the third embodiment is that a liquid-proof bank 43 that is bent toward the liquid-cooling member 2 is formed at the tip of the liquid-proof wall 4 on the protruding side.

By providing such a liquid-proof bank 43, for example, when the amount of the liquid leak L is particularly large, or when the apparatus is installed in an inclined or standing state, the liquid leak L reaches the tip of the liquid barrier wall 4. However, since it is blocked by the liquid-proof bank 43, it is possible to surely prevent the leakage from reaching the electrode terminals 11 and 12, and the electrode terminals 11 and 12 are electrically short-circuited by the leakage. The occurrence of defects can be prevented even more reliably than in the first embodiment.
Since other configurations and operational effects are the same as those in the first embodiment, detailed description thereof is omitted here.

Embodiment 4 FIG.
7 is a perspective view showing a main part of a semiconductor device according to Embodiment 4 of the present invention, FIG. 8 is a front sectional view of the same device, FIG. 9 is a side sectional view of the same device, and is shown in FIGS. Components identical or corresponding to those in the first embodiment are denoted by the same reference numerals.

  The feature of the fourth embodiment is that the liquid barrier 4 provided for the power supply electrode terminal 11 out of the liquid barrier 4 provided in the main body 10 of the semiconductor module 1 is Side wall portions 44 are individually erected between the electrode terminals 11 adjacent to each other so as to surround a side perpendicular to the protruding direction. Further, with respect to the liquid-proof wall 4 provided for the control signal electrode terminal 12, side wall portions 44 are formed so as to surround the left and right ends in the arrangement direction orthogonal to the protruding direction of the electrode terminal 12.

  Thus, by providing the side wall 44 integrally with the liquid barrier 4, for example, even when there is a particularly large amount of liquid leakage or when the apparatus is installed in an inclined or standing state, the side wall 44 can leak the liquid. Can be reliably prevented from flowing from the side surface of the liquid barrier wall 4 to the electrode terminals 11 and 12 side, and the occurrence of a problem that the electrode terminals 11 and 12 are electrically short-circuited due to leakage is further ensured. Can be prevented. Further, the side wall portion 44 is interposed between the electrode terminals 11 for the power supply, so that the space insulation distance between the electrode terminals 11 can be increased and the insulating property can be enhanced. It is done.

In the fourth embodiment, with respect to the liquid barrier 4 provided for the control signal electrode terminal 12, the side wall portions 44 are provided only at the two left and right ends in the arrangement direction of the electrode terminals 12. However, as in the case of the electrode terminal 11 for power supply, it is also possible to adopt a configuration in which the side wall portions 44 are individually erected between the electrode terminals 12 adjacent to each other. Conversely, instead of forming the side wall portions 44 individually for the power supply electrode terminals 11, the side wall portions 44 may be formed at two locations on the left and right ends in the arrangement direction of the electrode terminals 12.
Since other configurations and operational effects are the same as those in the first embodiment, detailed description thereof is omitted here.

Embodiment 5 FIG.
A feature of the fifth embodiment of the present invention is that in each of the first to fourth embodiments described above, the surface of the liquid-proof wall 4 (including the surfaces of the liquid-proof bank 43 and the side wall 44 in the third and fourth embodiments). While the water-repellent treatment is performed, the surface of the liquid cooling member 2 that faces the liquid-proof wall 4 is subjected to a hydrophilic treatment.

  The water repellent treatment in this case can be realized by, for example, applying a water repellent coating material such as waxes or fluororesin to the surface of the liquid barrier 4. The hydrophilic treatment can be realized, for example, by applying a hydrophilic coating material such as titanium oxide powder to a predetermined surface of the liquid cooling member 2.

  Here, as the coolant flowing in the flow passage 20 of the liquid cooling member 2, for example, an aqueous solution having a relatively high viscosity such as ethylene glycol is used, so that the surface of the liquid barrier 4 is subjected to water repellent treatment. Thus, the liquid leakage can be prevented from spreading on the surface of the liquid-proof wall 4, while the liquid cooling member 2 is subjected to a hydrophilic treatment on the surface of the liquid-cooling member 2 facing the liquid-proof wall 4. It is possible to promote spreading on the surface. For this reason, it is possible to prevent the leaked liquid from spreading over the liquid barrier 4 and short-circuiting the electrode terminals 11 and 12.

  In addition, it is preferable to perform both the water-repellent treatment on the surface of the liquid-proof wall 4 and the hydrophilic treatment on the surface of the liquid-cooled member 2 as in the fifth embodiment. It is also possible to perform only one of the water repellent treatment on the surface 4 and the hydrophilic treatment on the surface of the liquid cooling member 2 facing the liquid barrier 4.

  The present invention is not limited to the individual configurations of the first to fifth embodiments, and it is needless to say that the configurations of the first to fifth embodiments can be appropriately combined.

  Moreover, in said Embodiment 1-5, although the case where the electrode terminals 11 and 12 protruded from the opposite side surfaces 19 of the main-body part 10 of the semiconductor module 1 was demonstrated, this invention is such For example, the present invention can be applied to a configuration in which the electrode terminal protrudes from the upper portion of the main body portion as in the prior art, and the same effect can be obtained.

  Further, in the above first to fifth embodiments, the case where the power switching element 13 such as the power IGBT is provided as the semiconductor element constituting the semiconductor module 1 has been described. The present invention is not limited to this, and can be similarly applied to a semiconductor device including the semiconductor module 1 in which a plurality of highly integrated and high-speed logic elements are packaged.

It is a perspective view which shows the principal part of the semiconductor device in Embodiment 1 of this invention. It is sectional drawing of the semiconductor module which comprises the apparatus. It is sectional drawing which expands and shows a part of the apparatus. It is action | operation explanatory drawing of the liquid-proof wall provided in the semiconductor module of the apparatus. It is sectional drawing which shows the structure of the semiconductor device in Embodiment 2 of this invention. It is sectional drawing which shows the structure of the semiconductor device in Embodiment 3 of this invention. It is a perspective view which shows the principal part of the semiconductor device in Embodiment 4 of this invention. It is front sectional drawing of the same apparatus. It is side surface sectional drawing of the apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor module, 10 main-body part, 11 Power supply side electrode terminal,
12 control signal side electrode terminal, 13 switching element (semiconductor element), 19 side surface,
2 liquid cooling members, 20 flow passages, 21 openings, 3 seal members, 4 liquid barriers,
43 Liquidproof bank, 44 Side wall.

Claims (6)

A semiconductor module on which a semiconductor element is mounted; and a liquid cooling member having a cooling liquid flow passage therein and having an opening formed so that a part of the flow passage is exposed to the outside. In the direct liquid cooling type semiconductor device in which the module and the liquid cooling member are integrally joined via a sealing member, and the cooling surface of the semiconductor module faces the opening of the flow path,
The semiconductor module is integrally provided with a liquid barrier wall that is located between the electrode terminal and the seal member and projects outwardly from the side surface substantially orthogonal to the joint surface with the liquid cooling member. A semiconductor device provided. 2. The semiconductor device according to claim 1, wherein the liquid barrier wall is formed so as to protrude from a side surface orthogonal to a joint surface with the liquid cooling member. 3. The semiconductor device according to claim 1, wherein a liquid-proof bank bent toward the liquid-cooling member is formed at a distal end portion of the liquid-proof wall on the projecting side. 5. The semiconductor according to claim 1, wherein a side wall portion is formed on the liquid barrier so as to surround a side perpendicular to the protruding direction of the electrode terminal. apparatus. 5. The semiconductor device according to claim 1, wherein at least a surface of the liquid barrier wall on the liquid cooling member side is subjected to water repellent treatment. 6. The semiconductor device according to claim 1, wherein at least a surface of the liquid cooling member on the liquid barrier wall side is subjected to a hydrophilic treatment.

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