JP5232133B2 - Semiconductor device - Google Patents

Description

  The present invention relates to a semiconductor device, and more particularly to a semiconductor device capable of cooling a semiconductor element.

  Conventionally, semiconductor devices are disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-5014 (Patent Document 1), Japanese Patent Application Laid-Open No. 2008-16872 (Patent Document 2), and Japanese Patent Application Laid-Open No. 10-22428 (Patent Document 3). .

JP 2006-5014 A JP 2008-16872 A Japanese Patent Laid-Open No. 10-22428

  In the conventional technique, the semiconductor module and the cooling pipe are laminated to cool both sides of the semiconductor module. However, there is a problem that it is difficult to improve the cooling performance, improve the variation, and improve the warp or deformation of the semiconductor module due to heat.

  Accordingly, the present invention has been made to solve the above-described problems, and is a semiconductor device capable of improving the cooling performance of a semiconductor element and suppressing warpage or deformation of the semiconductor module due to heat. The purpose is to provide.

  A semiconductor device according to the present invention includes a semiconductor module including a semiconductor element, and a cooler having a nozzle that fits into the semiconductor module, and the semiconductor module inserts the tip of the nozzle to which the semiconductor element is bonded. A cylindrical heat diffusing portion having a possible opening, a fin provided on an inner surface of the opening, and a mold unit that integrates the semiconductor element and the heat diffusing unit. Then, the semiconductor element joined to the heat diffusion part is cooled by colliding the refrigerant with the heat diffusion part.

  In the semiconductor device configured as described above, since the jetted and collided refrigerant reaches the inner surface of the thermal diffusion unit and the thermal diffusion unit is uniformly cooled, the ability to cool the semiconductor element joined to the thermal diffusion unit is provided. improves. Moreover, since the thermal diffusion part and the semiconductor element are integrated in the mold part, warpage and deformation of the semiconductor element due to heat can be reduced.

  Preferably, the plurality of semiconductor modules are arranged in parallel with the cooler. In this case, since each semiconductor element can be cooled by the refrigerant supply unit, the difference in cooling capacity between the upstream and downstream pipes due to a single jet is reduced as in the prior art. As a result, a cooling structure optimal for a semiconductor device having a plurality of semiconductor elements can be provided.

Preferably, the cooler is detachably fitted to the semiconductor module.
Preferably, the cooler includes a coolant supply unit disposed in the cooler, and the coolant is sent from the coolant supply unit to the heat diffusion unit via the nozzle, and the refrigerant in contact with the heat diffusion unit is collected in the cooler. It is done.

  Preferably, a thermal conductive material having higher thermal conductivity than the material constituting the thermal diffusion unit is embedded in the thermal diffusion unit.

  Preferably, a plurality of semiconductor elements are joined to the thermal diffusion part.

  According to the present invention, it is possible to provide a semiconductor device in which the cooling performance of the semiconductor element is improved and the warpage or deformation of the semiconductor module due to heat can be reduced.

It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 1 of this invention. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the II-II line | wire in FIG. It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 2 of this invention. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the IV-IV line in FIG. It is a figure of the semiconductor device which has a semiconductor module seen from the direction shown by arrow V in FIG. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the VI-VI line in FIG. It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 3 of this invention. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the VIII-VIII line in FIG. FIG. 9 is a perspective view illustrating a state where the semiconductor module and one cooler are separated from each other in the semiconductor device illustrated in FIGS. 7 and 8. It is a figure which shows the cooling structure according to the comparative example where the thermal diffusion part has a flat shape and the cooling performance at the end part is low. It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 4 of this invention. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the XII-XII line | wire in FIG. FIG. 12 is a diagram showing a flow of heat generated from a semiconductor element in the semiconductor device shown in FIG. 11. It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 5 of this invention. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the XV-XV line | wire in FIG. FIG. 15 is a diagram showing a flow of heat generated from a semiconductor element in the semiconductor device shown in FIG. 14. It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 6 of this invention. It is sectional drawing of the nozzle for a fin and a refrigerant | coolant supply along the XVIII-XVIII line in FIG. FIG. 18 is a diagram showing a flow of heat generated from a semiconductor element in the semiconductor device shown in FIG. 17. It is sectional drawing of the semiconductor device which has a semiconductor module according to Embodiment 7 of this invention. It is sectional drawing of the fin and the nozzle for refrigerant | coolant supply along the arrow XXI-XXI line in FIG. FIG. 21 is a diagram showing a flow of heat generated from a semiconductor element in the semiconductor device shown in FIG. 20.

  Embodiments of the present invention will be described below with reference to the drawings. In the following embodiments, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated. In addition, the embodiments can be combined.

(Embodiment 1)
1 is a cross-sectional view of a semiconductor device having a semiconductor module according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line II-II in FIG. With reference to FIG. 1 and FIG. 2, the semiconductor device 1 includes a semiconductor module 7 and a cooler 8. A semiconductor module 7 as a semiconductor cooling module includes a semiconductor element 2, an input electrode 3 A, an output electrode 3 B, an insulating material 4, and a heat diffusion part 5, which are joined together and are integrally fixed by a resin mold 6. ing. The heat diffusing unit 5 is made of a cylindrical or rectangular high heat conductive material (such as copper or aluminum). Openings 5a are provided on the opposite side of the joint with the semiconductor element 2, and heat radiation fins 9 are formed radially inside. Moreover, the connection part 10 with the attachment / detachment function is formed in the outer peripheral part. The connection unit 10 is configured by a screw, a quick coupling, an O-ring groove, or the like. The type of the semiconductor element 2 is not particularly limited. However, if the present invention is applied to the semiconductor element 2 having a large calorific value, such as an IGBT (Insulated Gate Bipolar Transistor), the effect is high.

  The semiconductor module 7 is connected to the cooler 8 at the connection portion 10. From the nozzle portion 11 formed in the cooler 8, the refrigerant 12 is jetted into the opening 5 a of the heat diffusing portion in the direction indicated by the arrow 12 a, and heat exchange (cooling) is performed in the radiating fins 9 of the heat diffusing portion 5. . The shape of the cooler 8 is a rectangular tube shape in this example, but is not limited to this example, and may be a cylindrical shape. A refrigerant supply unit 111 is provided in the cooler 8. The refrigerant supply unit 111 has a rectangular tube shape in this example, but is not limited to this example, and may have a cylindrical shape.

  The jetted refrigerant flows back in the direction indicated by the arrow 12b, and is discharged in the direction indicated by the arrow 12c.

  The semiconductor device 1 includes a semiconductor module 7 including a semiconductor element 2 and a cooler 8 having a nozzle portion 11 that fits into the semiconductor module 7. The semiconductor module 7 includes a nozzle portion to which the semiconductor element 2 is bonded. 11 is a cylindrical heat diffusing portion 5 having an opening 5a into which the tip portion of 11 can be inserted, a fin 9 provided on the inner surface of the opening 5a, and a mold for integrating the semiconductor element 2 and the heat diffusing portion 5 together. The cooler 8 includes a resin mold 6 as a part, and cools the semiconductor element 2 joined to the heat diffusion part 5 by causing the refrigerant 12 to collide with the heat diffusion part 5 via the nozzle part 11. The cooler 8 is detachably fitted to the semiconductor module 7. The cooler 8 includes a refrigerant supply unit 111 disposed in the cooler 8, and the refrigerant 12 is sent from the refrigerant supply unit 111 to the heat diffusion unit 5 via the nozzle unit 11 to exchange heat with the heat diffusion unit 5. The cooled refrigerant 12 is collected in the cooler 8.

(Embodiment 2)
FIG. 3 is a cross-sectional view of a semiconductor device having a semiconductor module according to the second embodiment of the present invention. FIG. 4 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line IV-IV in FIG. FIG. 5 is a diagram of a semiconductor device having a semiconductor module viewed from the direction indicated by the arrow V in FIG. FIG. 6 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line VI-VI in FIG.

  In the second embodiment, an example of a semiconductor device in which two semiconductor elements 2 are installed is shown. In this case, the refrigerant 12 is ejected from the rectangular nozzle portion 11 in which the plate-like heat radiation fins 9 are arranged in parallel in the heat diffusion portion 5 and the longitudinal direction is set to be perpendicular to the fin row. In these configurations, the shape of the radiating fins 9 may be a pin shape or a fine groove shape in addition to a plate shape.

  Moreover, the opening of the nozzle part 11 does not need to be a single hole, may be porous, and a notch may be formed at the end.

  Further, the distance (collision distance) from the tip of the nozzle portion 11 to the inner bottom surface of the opening of the thermal diffusion portion 5 is preferably set to 10 times or less the nozzle opening equivalent diameter. Jet collision and disturbance effects are obtained, and high thermal conductivity is maintained. In general, this distance is a maximum of 6 to 8 times.

  By adopting the configurations of the first and second embodiments as described above, even if a module component fails or malfunctions, it can be individually attached and detached and replaced, so that the entire loss of the semiconductor device 1 can be avoided.

  In addition, it is possible to periodically remove dirt and deposits on the heat dissipating fins 9 that cause a decrease in cooling performance by the liquid. As dirt and deposits, there are dust adhesion, scale adhesion at the time of boiling, etc., and these act as heat resistance.

  Furthermore, a large-scale heat and pressure manufacturing process for joining the semiconductor module 7 on which the elements are mounted and the cooler 8 by brazing, soldering, or the like is unnecessary, and costs can be reduced.

  Further, thermal stress can be reduced by suppressing warpage due to the high rigidity of the thermal diffusion portion 5 and restraining the joining member by the resin mold 6 (suppressing distortion caused by a difference in linear expansion between the members).

  Further, since the semiconductor module 7 and the cooler 8 are joined through the connection part 10 such as a screw and are not completely adhered (joined), the structure is less affected by stress and strain due to thermal expansion during device operation. . That is, it has the effect of relaxing the stress.

  Moreover, since the manufacturing process using the heat and pressure is not necessary, problems such as thermal deformation caused by the assembly process can be avoided.

  Furthermore, a high heat transfer coefficient can be obtained by an impinging jet directly below the semiconductor element 2, an increase in the heat transfer area of the heat diffusion portion 5 and an increase in heat capacity.

(Embodiment 3)
FIG. 7 is a sectional view of a semiconductor device having a semiconductor module according to the third embodiment of the present invention. FIG. 8 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line VIII-VIII in FIG. FIG. 9 is a perspective view showing a state where the semiconductor module and one cooler are separated from each other in the semiconductor device shown in FIGS. 7 and 8.

  7 to 9, in semiconductor device 1 according to the third embodiment of the present invention, semiconductor element 2, input electrode 3 </ b> A, insulating material 4, and thermal diffusion portion are arranged on both sides of output electrode 3 </ b> B as a center. The semiconductor device 1 is composed of a semiconductor module 7 in which 5 is arranged symmetrically in order and the whole is integrally fixed by a resin mold 6 and a cooler.

  Both ends of the semiconductor module 7 are openings 5a of the heat diffusing portion 5, and inside the heat radiating fins 9, and a connecting portion 10 having an attaching / detaching function is formed on the outer peripheral portion. The semiconductor module 7 is coupled to the cooler 8 through the connection portion 10, and heat exchange (cooling) is performed between the refrigerant 12 ejected from the nozzle portion 11 of the cooler 8 and the heat radiation fins 9.

  The input electrode 3 </ b> A and the output electrode 3 </ b> B are arranged in parallel to each other and are joined to the electrical connector 13. The semiconductor device 1 is assembled by mounting a plurality of semiconductor modules 7 on the cooler 8 and connecting the electrical connector 13 to the input electrode 3A and the output electrode 3B of the semiconductor module 7.

  That is, the semiconductor module 7 is cooled by the two coolers 8 and 108. The plurality of semiconductor modules 7 are arranged in parallel with the coolers 8 and 108.

  In the semiconductor device 1 configured as described above, the semiconductor module 7 has a symmetrical shape with the output electrode 3B as the center, and therefore, warpage and deformation due to a difference in linear expansion coefficient can be reduced.

  Further, since the positive and negative input electrodes 3A are arranged close to each other in parallel, the parasitic inductance (L) is canceled (mutual inductance effect), and the switching loss is reduced. Switching loss is proportional to parasitic inductance.

(Embodiment 4)
FIG. 10 is a diagram illustrating a cooling structure according to a comparative example in which the heat diffusion portion has a flat shape and the cooling performance at the end portion is low. In the semiconductor device 1 according to the comparative example, bonding materials 4 a and 4 b are provided on both sides of the insulating material 4. High thermal conductivity (cooling performance) is obtained in the vicinity of the center of the jet collision portion, but the cooling performance decreases along the radial direction. That is, the cooling performance is highest in the portion where the refrigerant 12 ejected in the direction indicated by the arrow 12a collides, and the cooling performance decreases as the diffusion from this portion in the direction indicated by the arrow 12b. When fins are arranged on the collision surface (bottom surface), if the fins are miniaturized or the specified areas are expanded in order to secure an enlarged heat transfer area, the pressure loss increases and the module size increases.

  FIG. 11 is a sectional view of a semiconductor device having a semiconductor module according to the fourth embodiment of the present invention. 12 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line XII-XII in FIG. FIG. 13 is a diagram showing a flow of heat generated from the semiconductor element in the semiconductor device shown in FIG.

  Referring to FIG. 11 to FIG. 13, the semiconductor element 2, the insulating material 4, and the heat diffusion unit 5 are stacked in this order, and the refrigerant 12 is ejected toward the heat diffusion unit 5 through the nozzle unit 11. In the heat sink structure cooled by the above, the heat diffusing portion 5 has a cylindrical or prismatic shape, has an opening 5a on the side facing the element bonding surface, has a hollow shape, and has heat radiation fins 9 formed on the inner side surface and bottom surface. ing. The heat generated from the semiconductor element 2 flows in the direction indicated by arrows 2a, 2b, and 2c and is transmitted to the heat diffusion unit 5, and further flows in the direction indicated by arrows 2d and 2e in the heat diffusion unit 5 to heat the refrigerant 12. Is transmitted. In the following embodiments including this embodiment, descriptions of the resin mold and the cooler are omitted.

  In the semiconductor device 1 configured as described above, the cooling capability (equivalent heat transfer coefficient) around the semiconductor element 2 is greatly improved by disposing the heat radiation fins 9 on the inner side surface of the thermal diffusion portion 5. As a result, most of the element heat generation is cooled via the side surface of the thermal diffusion section 5 using the temperature difference accompanying the temperature drop around the element as a driving force, so that the semiconductor element 2 is uniformly cooled. Further, by making the heat flow from the semiconductor element 2 uniform, the thermal load on the jet collision portion directly below the semiconductor element 2 is reduced, and the element temperature can be lowered.

  Furthermore, by properly setting the thickness T and height H (radiation fin length) of the thermal diffusion part 5, the cooling performance of the peripheral part can be increased with the same fin specifications and base area, thereby improving the performance. Therefore, it is possible to avoid the problems caused by these, without miniaturizing the fins or expanding the base area. For example, if fins are miniaturized, the manufacturing cost increases, and if the base area is enlarged, the module projection area increases, leading to an increase in size.

(Embodiment 5)
FIG. 14 is a sectional view of a semiconductor device having a semiconductor module according to the fifth embodiment of the present invention. FIG. 15 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line XV-XV in FIG. FIG. 16 is a diagram showing a flow of heat generated from the semiconductor element in the semiconductor device shown in FIG.

  Referring to FIGS. 14 to 16, in semiconductor device 1 according to the fifth embodiment of the present invention, fins have a radial shape. The heat radiating fins 9 extend from the center toward the outer periphery, and the refrigerant flow indicated by the arrow 12b also flows along this direction.

  The semiconductor device 1 according to the fifth embodiment configured as described above has the same effects as the semiconductor device 1 according to the first embodiment.

(Embodiment 6)
FIG. 17 is a cross sectional view of a semiconductor device having a semiconductor module according to the sixth embodiment of the present invention. 18 is a cross-sectional view of the fins and the refrigerant supply nozzle along the line XVIII-XVIII in FIG. FIG. 19 is a diagram showing a flow of heat generated from the semiconductor element in the semiconductor device shown in FIG.

  Referring to FIGS. 17 to 19, in the semiconductor device according to the sixth embodiment of the present invention, a part of thermal diffusion portion 5 is filled with thermal conductive material 51. The heat conductive material 51 is an anisotropic high heat conductive material provided in the outer peripheral portion of the heat diffusion portion 5. Examples of this material include oriented graphite (thermal conductivity 1 kW / mK) or self-excited heat pipe (thermal conductivity> 1 kW / mK). By adopting such a configuration, the thermal conductivity of the outer peripheral portion is greatly improved, and uniform cooling can be more reliably achieved. A thermal conductive material 51 having higher thermal conductivity than the material constituting the thermal diffusion unit 5 is embedded in the thermal diffusion unit 5.

(Embodiment 7)
FIG. 20 is a sectional view of a semiconductor device having a semiconductor module according to the seventh embodiment of the present invention. FIG. 21 is a cross-sectional view of the fin and the refrigerant supply nozzle along the arrow XXI-XXI line in FIG. FIG. 22 is a diagram showing a flow of heat generated from the semiconductor element in the semiconductor device shown in FIG.

  In semiconductor device 1 according to the seventh embodiment, a plurality of semiconductor elements 2, 21, and 31 are mounted on thermal diffusion unit 5. Semiconductor elements 21 and 31 having a lower thermal load than the semiconductor element 2 are disposed on the side surface of the thermal diffusion portion 5. A plurality of semiconductor elements 2, 21, 31 are joined to the thermal diffusion part 5. Thereby, the physique of a module can be reduced by utilizing a heat sink structure three-dimensionally.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be used, for example, in the field of semiconductor devices mounted on vehicles.

  DESCRIPTION OF SYMBOLS 1 Semiconductor device 2,21,31 Semiconductor element, 3A input electrode, 3B output electrode, 4a, 4b Bonding material, 4 Insulating material, 5 Thermal diffusion part, 5a Opening part, 6 Resin mold, 7 Semiconductor module, 8, 108 Cooler, 9 Radiation fin, 10 Connection part, 11 Nozzle part, 12 Refrigerant, 13 Electrical connector, 51 Thermal conduction material, 111 Refrigerant supply part.

Claims (6)

A semiconductor module including a semiconductor element;
A cooler having a nozzle that fits into the semiconductor module;
The semiconductor module is
A cylindrical heat diffusion part having an opening into which the tip part of the nozzle can be inserted, to which the semiconductor element is joined,
A fin provided on an inner surface of the opening;
Including a mold part for integrating the semiconductor element and the thermal diffusion part,
The said cooler is a semiconductor device which cools the said semiconductor element joined to the said thermal diffusion part by making a refrigerant collide with the said thermal diffusion part through a nozzle.   The semiconductor device according to claim 1, wherein the plurality of semiconductor modules are arranged in parallel to the cooler.   The semiconductor device according to claim 1, wherein the cooler is detachably fitted to the semiconductor module.   The cooler includes a coolant supply unit disposed in the cooler, the coolant is sent from the coolant supply unit to the heat diffusion unit via the nozzle, and the coolant in contact with the heat diffusion unit is the The semiconductor device according to claim 1, wherein the semiconductor device is collected in a cooler.   5. The semiconductor device according to claim 1, wherein a thermal conductive material having higher thermal conductivity than a material constituting the thermal diffusion unit is embedded in the thermal diffusion unit.   6. The semiconductor device according to claim 1, wherein a plurality of the semiconductor elements are joined to the thermal diffusion portion.

Images