JP2005322879A - Substrate for semiconductor device, semiconductor module and electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate for the semiconductor device of the structure which has excellent cooling capability and which is simplified. <P>SOLUTION: In a substrate 1B for carrying the semiconductor device 2, a conducting layer 4 for attaching the semiconductor device 2 is formed on one surface side of an insulating layer 3, and a heat dissipating device 5 is connected directly to the other surface side of the insulating layer 3. The heat dissipation device 5 is preferred to be a liquid cooling type cooling plate 7 having a plurality of fine passages 7a through which cooling liquid flows. Moreover, as the insulating layer 3, it is preferred to use an insulating resin, an insulating resin composition obtained by mixing thermally conductive filler with the insulating resin, or a composite material obtained by immersing an insulating cloth with the insulating resin or the insulating resin composition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a substrate for mounting a semiconductor element, and more particularly to a semiconductor element substrate having a cooling function.

  In this specification, the term “aluminum” is used to include both aluminum and its alloys, and the term “copper” is used to include both copper and its alloys.

  Semiconductor elements, such as power semiconductor elements, generate heat when energized, and the amount of generated heat tends to increase with the recent increase in capacity. Since heat generation greatly affects the reliability and life of the semiconductor element, it is necessary to provide a heat dissipating part in the module in which the semiconductor element is attached to the substrate to suppress the temperature rise in the semiconductor element and its vicinity. On the other hand, downsizing of semiconductor modules has been desired due to the trend toward reduction in size and weight of various electronic products equipped with semiconductor modules.

  FIG. 10 shows an example of a semiconductor module (50) in which a semiconductor element (52) is mounted on a semiconductor element substrate (51) and a heat dissipation device (60) mounted in the semiconductor module (50).

  In the semiconductor module (50), the semiconductor element substrate (51) is formed by laminating an insulating layer (54) on a metal plate (53) made of copper or aluminum, and further a conductive layer (55) made of copper foil or aluminum foil. Are laminated and integrated. The semiconductor element (52) is attached to the conductive layer (55) of the substrate (51) using solder (56). Further, a heat radiating device (60) is attached to the metal plate (53) side by a bolt (not shown) via a heat transfer grease (57). In the illustrated example, a heat sink in which comb-like fins are erected is used as the heat dissipation device (60).

  A semiconductor element substrate having a cooling function has also been proposed by integrally bonding a semiconductor element substrate and various heat dissipation devices (see Patent Documents 1 and 2).

  The semiconductor element substrate described in Patent Document 1 is obtained by bonding a metal layer to the surface of a ceramic insulating substrate, and metal-bonding the metal layer and the heat sink by heat treatment to integrate them.

The substrate for a semiconductor element described in Patent Document 2 is obtained by integrally integrating an insulating substrate made of ceramic or resin and a heat dissipation member via an adhesive layer made of a brazing material or an adhesive.
Japanese Patent No. 3452011 JP 2003-60136 A

  However, in the structure shown in FIG. 10, depending on the flatness and surface roughness of the mounting surface of the semiconductor module (50) and the heat dissipation device (60), a large thermal resistance is generated in the heat transfer grease (57), and the heat dissipation performance is improved. May decrease. If sufficient heat dissipation performance cannot be obtained, the heat dissipation area of the heat dissipation device must be expanded to cope with the increasing amount of heat generation, which is contrary to the miniaturization of the semiconductor module. There is also a problem that the number of assembly steps increases.

  In the semiconductor element substrate described in Patent Document 1, the metal plate (53) as shown in FIG. 10 is not provided and the structure is simplified. However, the metal for joining the ceramic insulating substrate and the metal heat dissipation plate is used. A layer is required. Moreover, before joining with a heat sink, it is necessary to braze a metal layer to a ceramic insulating board | substrate previously. For this reason, further simplification of the structure and the manufacturing process is required.

  The semiconductor element substrate described in Patent Document 2 also has a simplified structure without a metal plate (53) as shown in FIG. 10, but requires an adhesive layer that joins the insulating substrate and the heat dissipation member. . In addition, when an adhesive is used as the adhesive layer, there is a problem in that the heat dissipation ability is lowered because the thermal conductivity is lowered.

  In view of the background art described above, the present invention provides a substrate for a semiconductor element having a simplified structure with excellent cooling capability, and further mounting a semiconductor module using the semiconductor element substrate and the semiconductor module The purpose is to provide electric vehicles.

  In order to achieve the above object, a substrate for a semiconductor device of the present invention has the configurations described in [1] to [11] below.

  [1] A semiconductor element on which a semiconductor element is mounted, wherein a current-carrying layer for attaching the semiconductor element is formed on one side of the insulating layer, and a heat dissipation device is directly joined on the other side. Substrate.

  [2] The semiconductor element substrate according to [1], wherein the heat dissipation device is a liquid-cooled cooling plate having a plurality of fine passages through which a coolant flows.

[3] The liquid cooling type cooling plate is
At least one flat porous tube having a fine passage through which a cooling liquid flows, two header portion forming recesses spaced apart from each other, and a tube that is formed between both header portion forming recesses and accommodates the tube A case main body provided with a housing recess, and a cover plate that is superposed on the case main body,
The porous tube is accommodated in the tube accommodating recess so as to communicate with both the header portion forming recesses, and in the state where the cover plate is superposed on the case body, the porous tube is connected to the case body and the case body. While sandwiched between the lid plates, the opening portions of the header portion forming recesses are closed by the lid plate to form two header portions, and the case body, the porous tube, and the lid plate are The semiconductor element substrate according to [2], wherein the semiconductor element substrate is integrally joined so as to prevent leakage of a coolant flowing through the header portion.

  [4] In the liquid cooling type cooling plate, a first connection port member connected to the cooling liquid inflow pipe is connected to one of the two header parts and connected to the cooling liquid outflow pipe. The semiconductor element substrate according to [3], wherein the second connection port member to be communicated is connected to the other header portion.

  [5] The semiconductor element substrate according to any one of [2] to [4], wherein an equivalent diameter of the fine passage of the liquid cooling type cooling plate is set in a range of 0.05 to 1.7 mm. .

  [6] The semiconductor element substrate according to any one of [1] to [5], wherein the insulating layer is made of an insulating resin.

  [7] The semiconductor element substrate according to any one of [1] to [5], wherein the insulating layer is made of an insulating resin composition in which a heat conductive filler is blended with an insulating resin.

  [8] The insulating layer is a composite material obtained by impregnating an insulating fabric with an insulating resin, or an insulating resin composition in which an insulating resin is mixed with a heat conductive filler. The substrate for a semiconductor element according to any one of the above.

  [9] The semiconductor element substrate according to any one of [6] to [8], wherein the insulating resin is at least one of an epoxy resin and a polyimide resin.

[10] the thermally conductive _{filler, SiO 2, Al 2 O 3} , BeO, MgO, Si 3 N 4, a semiconductor device substrate according to at least one a [7] or [8] of BN .

  [11] The semiconductor element substrate according to any one of [7], [8], and [10], wherein the content of the heat conductive filler in the insulating resin composition is 40 to 90% by volume.

  The semiconductor module of the present invention has the configuration described in [12] below.

  [12] A semiconductor module comprising a semiconductor element attached to a conductive layer of the semiconductor element substrate according to any one of [1] to [11].

  The electric vehicle of the present invention has a configuration described in [13] and [14] below.

  [13] An electric vehicle on which the semiconductor module described in [12] is mounted.

  [14] A radiator is mounted, and the cooling liquid cooled by the radiator flows into the liquid cooling type cooling plate, and the cooling liquid flowing out from the liquid cooling type cooling plate is cooled by the radiator. The electric vehicle according to [13].

  The substrate for a semiconductor element according to the invention of [1] has an excellent cooling ability with a small thermal resistance because the insulating layer is directly bonded to the heat dissipation device. Moreover, since the structure is simple, the manufacturing process is simple.

  According to the semiconductor element substrate according to the invention [2], a particularly excellent cooling capacity can be obtained.

  According to the semiconductor element substrate according to the invention [3], a further excellent cooling capacity is obtained and the strength is also excellent.

  According to the semiconductor element substrate according to the invention [4], it is possible to easily connect the coolant inflow pipe and the outflow pipe.

  The semiconductor element substrate according to the invention of [5] has a particularly excellent cooling capacity.

  According to the semiconductor element substrate according to the invention [6], an excellent cooling ability can be obtained because the adhesion between the insulating layer and the heat dissipation device is high. Moreover, it is possible to manufacture a large area substrate because it is harder to break than the ceramic insulating layer.

  According to the semiconductor element substrate according to the invention [7], in addition to the high adhesion between the insulating layer and the heat dissipation device, the thermal conductivity of the insulating layer is improved by the heat conductive filler, thereby providing an excellent cooling capacity. Is obtained.

  According to the semiconductor element substrate according to the invention [8], the strength of the insulating layer is high, and dimensional change, warpage, and twisting with time are suppressed.

  According to the semiconductor element substrate according to the invention of [9], the insulating layer having excellent heat resistance and suppressed deformation due to thermal expansion is formed.

  According to the semiconductor element substrate according to the invention [10], an insulating layer having particularly high thermal conductivity can be formed.

  According to the semiconductor element substrate according to the invention of [11], an insulating layer having particularly high thermal conductivity can be formed.

  According to the semiconductor module according to the invention of [12], the semiconductor element is reliably cooled, and high reliability can be secured over a long period of time in its operation.

  According to the electric vehicle of the invention [13], the semiconductor element for an electric vehicle is reliably cooled.

  According to the electric vehicle of the invention [14], the coolant circulates the cooling plate through the radiator, and the semiconductor element can be easily cooled.

  FIG. 1 schematically shows the structure of a semiconductor element substrate (1A) according to an embodiment of the present invention and a semiconductor module (S1) in which a semiconductor element (2) is mounted on the semiconductor element substrate (1A). Show.

  The semiconductor element substrate (1A) has an energization layer (4) formed on one side of the insulating layer (3), and the heat dissipation device (5) is directly bonded to the other side without an adhesive layer. This is a substrate that has been converted into a substrate. In the semiconductor module (S1), the semiconductor element (2) is attached to the conductive layer (4) of the semiconductor element substrate (1A) by solder (6) or the like. The attachment of the semiconductor element (2) is not limited to solder, and a known attachment method such as brazing or paste can be arbitrarily adopted.

  The conductive layer (4) is a layer made of a conductive material, and for example, copper foil or aluminum foil is used.

  The insulating layer (3) is made of an insulating material that can be directly bonded to the heat dissipation device (5). Specifically, an insulating resin, an insulating resin composition obtained by blending the insulating resin with a heat conductive filler, and a composite material obtained by impregnating an insulating fabric with the insulating resin or the insulating resin composition 3 Can recommend species. These resin-based insulating layers are harder to break than ceramics, and a large-area substrate can be manufactured.

  As the insulating resin, those having excellent heat resistance and a low coefficient of thermal expansion, being in close contact with a metal heat dissipation device and having excellent adhesiveness are preferable. An epoxy resin or a polyimide resin can be recommended as a resin that satisfies these conditions. Furthermore, the epoxy resin is particularly recommended because it has good adhesion to a copper material, has low hygroscopicity, and is inexpensive. Polyimide resin can be recommended because of its excellent chemical resistance and low thermal expansion coefficient in the thickness direction.

Further, by using an insulating resin composition in which a heat conductive filler is blended with the insulating resin, the heat conductivity of the insulating layer can be increased, and the heat dissipation performance can be improved. The thermally conductive filler is preferably an insulator having a high thermal conductivity, preferably a metal oxide or a metal nitride, specifically, SiO ₂ , Al ₂ O ₃ , BeO, MgO, Si ₃ N ₄ , BN can be exemplified. These thermally conductive fillers may be used alone or in combination of any plural kinds. The heat conductive filler has a higher thermal conductivity of the insulating layer (3) as the content in the resin composition increases, and is preferably 40 to 90% by volume. If it is less than 40% by volume, the effect of improving the thermal conductivity is poor. A particularly preferred content is 60 to 80% by volume. The particle size of the heat conductive filler is preferably 10 to 40 μm.

  Further, it is also preferable to use a composite material obtained by impregnating an insulating fabric with the above-described insulating resin or insulating resin composition as the insulating layer (3). The insulating fabric has an effect of imparting strength to the insulating layer (3) and preventing dimensional change, warpage, twisting, and the like due to heat generated by the semiconductor element (2). As the insulating fabric, a nonwoven fabric or a woven fabric made of inorganic fibers such as glass can be recommended. This is because the inorganic fiber cloth has less dimensional change, warpage, and twist than paper and synthetic fiber cloth. Such an insulating cloth is impregnated with an insulating resin or an insulating resin composition, but the cloth does not have to exist in the entire thickness direction of the insulating layer (3). A state in which a part of the functional resin composition is impregnated into the fabric and the resin is laminated on the fabric may be used. The insulating fabric is preferably as thin as possible because it prevents heat conduction and heat dissipation of the insulating layer (3).

  The thickness of the insulating layer (3) is preferably 0.01 to 0.5 mm in any of the above three types.

  The heat dissipation device (5) can be used regardless of the type as long as it can be directly bonded to the insulating layer (3). The heat radiation flat plate, the comb-like heat sink exemplified in FIG. 10, various heat tubes, etc. can be used regardless of air cooling or liquid cooling. Moreover, the strength as a substrate is ensured by the structure in which the insulating layer (3) and the heat dissipation device (5) are directly joined. That is, the strength reduction due to the removal of the metal plate (53) from the semiconductor substrate (51) in FIG. 9 is sufficiently compensated by the joining of the heat dissipation device (5).

  The heat dissipation device illustrated in FIG. 1 is an aluminum liquid-cooled cooling plate (5) made of a flat porous tube (7). Such a liquid-cooled cooling plate (5) is suitable as a heat dissipation device incorporated in the semiconductor element substrate (1A) because it is thin and has excellent heat dissipation performance.

  The perforated tube (7) has a plurality of fine passages (7a) each having a through-hole having a square cross section that penetrates the tube (7). The porous tube (7) is manufactured by, for example, extrusion or rolling, and such an extruded tube or a rolled tube is generally used for a heat exchanger. Then, a liquid cooling type cooling plate is manufactured by attaching a header part (not shown) and a connection port to the inflow / outflow pipe of the cooling liquid at both ends of the opening of the fine passage (7a).

  The cross-sectional shape of the fine passage (7a) in the present invention may be a substantially circular shape, a substantially elliptical shape, a substantially star shape, a polygonal shape, or the like. Further, the plurality of fine passages (7a) are not limited to those made of mutually independent holes, and the plurality of fine passages may communicate with each other.

  FIG. 2 is a graph showing the relationship between the equivalent diameter of the fine passage (7a) and the thermal resistance when the power of the pump for allowing the coolant to flow is constant in the liquid cooling plate (5) (graph) ). Note that the equivalent diameter de when the cross-sectional area A and the wet perimeter length p of the fine passage 7a is calculated as de = 4 A / p. In general, the absolute value of the thermal resistance changes depending on the size of the cooling plate (5), but the change tendency of the thermal resistance with respect to the equivalent diameter is the same as that shown in FIG.

  As shown in the figure, when the equivalent diameter of the fine passage (7a) of the perforated tube (7) is set in the range of 0.05 to 1.7 mm, the thermal resistance becomes small, and thus the high cooling capacity. It will be able to demonstrate. Furthermore, when the equivalent diameter is set in the range of 0.1 to 1.05 mm, the thermal resistance is further reduced, and in the case where the equivalent diameter is set in the range of 0.15 to 0.7 mm. Furthermore, the thermal resistance is further reduced, and a high cooling capacity can be exhibited. Therefore, the average equivalent diameter is preferably set in the range of 0.05 to 1.7 mm, more preferably in the range of 0.1 to 1.05 mm, and still more preferably in the range of 0.15 to 0.15 mm. It is desirable to set in the range of 0.7 mm.

  The above-mentioned joining of the energization layer (4), the insulating layer (3) and the heat dissipation device (5) is appropriately performed by a known method such as hot pressing.

  For example, the case where a thermosetting resin is used as the insulating resin of the insulating layer (3) will be described as an example.The conductive layer (4), the insulating layer (3), and the heat dissipation device (5) are stacked and Is sandwiched between stainless steel plates, further pressed through a cushioning material, and heated. By this hot pressing, the insulating layer (3) is cured and joined to the heat dissipation device (5) and the energization layer (4), and these are integrated.

  Also, as shown in FIG. 9, when the energization layer (4) is joined to a part of the insulating layer (3), the joining is performed using the alignment sheet (60) and the contact plate (61). That is, the conductive layer (4) is attached to the alignment sheet (60) and disposed on the insulating layer (3) through the contact plate (61) having a hole in the position corresponding to the conductive layer (4) to dissipate heat. Overlay on device (5). These are sandwiched between stainless steel plates (62), and further pressed through a cushion material (63) to be heated. As a result, the energization layer (4) is bonded to a predetermined position of the insulating layer (3). In addition, when using a composite material using an insulating resin composition or an insulating fabric as the insulating layer (3), a composition or composite material having a predetermined composition is prepared in advance, and is integrally joined by hot pressing as described above. To do.

  As the liquid cooling type cooling plate, as shown in FIG. 1, in addition to directly joining the insulating layer (3) with the porous tube (7) exposed, a case in which one or a plurality of porous tubes are loaded in the case is used. Can do.

  In the semiconductor element substrate (1B) shown in FIG. 3, a liquid cooling type cooling plate (8) in which a porous tube is loaded in a case is used, and the liquid cooling type cooling plate (8) is provided at a plurality of locations on one surface side. An insulating layer (3) and a conductive layer (4) are laminated.

  As shown in FIG. 4, the liquid cooling type cooling plate (8) includes a plurality of flats having a case body (10), a cover plate (30), and a plurality of fine passages (21) through which the cooling liquid flows. A perforated tube (20), a first connection port member (18a), and a second connection port member (18b). As these cooling plate materials, aluminum or copper having a high thermal conductivity can be recommended.

  As shown in FIG. 4, the case body (10) has a square shape in plan view, and two header-forming recesses (11a) (11b) spaced in parallel to each other on the left and right sides of the central portion on the upper surface side. Further, a tube housing recess (12) for housing the porous tube (20) is provided between the header forming recesses (11a) and (11b). Each of the header portion forming recesses (11a) and (11b) has a substantially square cross-sectional shape. The depth of the tube receiving recess (12) is set to be approximately the same as the thickness of the porous tube (20), and the depth of each header forming recess (11a) (11b) is the depth of the tube receiving recess (12). It is set deeper than the depth. The side surface of the case body (10) has a first connecting port member insertion hole (13a) communicating with one end of one header portion forming recess (11a) and the other header portion forming recess ( A second connecting port member insertion hole (13b) communicating with one end of 11b) is provided.

  The shape and size of the back surface of the lid plate (30) are set to be the same as the planar shape and size of the case body (10). Therefore, the cover plate (30) is in the state of being superposed on the case body (10), and the openings of the header forming recesses (11a) (11b) provided on the surface of the case body (10) and the tube housing The opening of the recess (12) can be closed. Then, an insulating layer (3) and a conductive layer (4) are attached to the surface of the lid plate (30) as shown in FIG. That is, in the liquid cooling type cooling plate (8) of the present embodiment, the surface of the lid plate (30) acts as a cooling surface (8A). The cooling surface (8A) of the lid plate (30) is formed flat. Similarly, the back surface of the lid plate (30) is formed flat.

  An inner surface and an upper end surface of the case body (10) are covered with a brazing material. Similarly, at least the back surface of the lid plate (30), the outer peripheral surface of the perforated tube (20), and the outer peripheral surfaces of the connecting port members (18a) (18b) are also coated with a brazing material.

  Each perforated tube (20) has a plurality of fine passages (21). Each fine passage (21) is formed of a fine through hole penetrating the tube (20) and having a square cross-sectional shape. The manufacturing method of the porous tube (20), the preferred cross-sectional shape of the fine passage (21), and the preferred equivalent diameter for exerting a high cooling capacity are the above-mentioned porous tube (7) and the fine passage (7a). Follow.

  The first connecting port member (18a) and the second connecting port member (18b) are formed in a short tube shape as shown in FIG. 7, and have a connecting port at one end. As shown in FIG. 8, the first connecting port member (18a) is connected to the coolant inlet pipe (19a) in a liquid-tight state, and the second connecting port member (18b) is connected to the coolant outlet pipe (19b) and the liquid. It is connected in a dense state.

  Next, the configuration of the cooling plate (8) will be described below based on the manufacturing method.

  First, as shown in FIGS. 4 to 7, a plurality of perforated tubes (20) arranged in a horizontal row in the tube housing recess (12) of the case body (10) are used to form both header portions. The recesses (11a) and (11b) are accommodated in a communicating manner. At this time, if necessary, a brazing material may be interposed between the bottom surface of the tube housing recess (12) of the case body (10) and the porous tube (20).

  Next, the lid plate (30) is superposed on the upper surface of the case body (10) so as to cover the entire porous tube (20). By superposing the lid plate (30) in this way, the porous tube (20) is sandwiched between the case body (10) and the lid plate (30), and both header portion forming recesses of the case body (10) ( The opening on the upper surface side of the case body (10) of 11a) and (11b) is closed by the lid plate (30), and as shown in FIG. 7, two header parts (14a) ( 14b) is formed. In the polymerization process of the lid plate (30), if necessary, between the case body (10) and the lid plate (30), between the porous tube (20) and the lid plate (30), A brazing material may be interposed.

  Further, the first and second connecting port members (18a) may be formed before the cover plate (30) polymerization step, simultaneously with the cover plate (30) polymerization step, or after the cover plate (30) polymerization step. (18b) is inserted into the corresponding insertion holes (13a) and (13b), and the first connection port member (18a) is connected to one of the header portion forming recesses (11a) and the second connection port member ( 18b) is communicatively connected to the other header forming recess (11b).

  Subsequently, the assembly of the cooling plate thus assembled is introduced into a brazing furnace, and the case main body (10), the perforated tube (20), the lid plate (30), and the first connection port member are brazed in the furnace. (18a) and the second connecting port member (18b) are joined and integrated together. In this joining process, the case main body (10) and the cover plate (30) are in a state that prevents leakage of the coolant (C) contained in the header portions (14a) and (14b), that is, in a liquid-tight state. They are joined and integrated with each other. Further, the first connection port member (18a) and the second connection port member (18b) are joined to the insertion holes (13a) and (13b) corresponding to the liquid-tight state, respectively. In FIG. 5, (47) is a filler fillet.

  The liquid cooling type cooling plate (8) shown in FIG. 3 is manufactured through the above steps. Then, similarly to the semiconductor element substrate (1A) described above, an insulating layer (3) and a current-carrying layer (4) are provided on the cooling surface (8A) of the liquid-cooled cooling plate (8). A substrate (1B) is manufactured. Further, a semiconductor module (S2, not shown) is manufactured by attaching the semiconductor element (2) to the energization layer (4) of the semiconductor element substrate (1B).

  In the liquid cooling type cooling plate (8), since the perforated tube (20) is accommodated in the predetermined recess (12) of the case body (10), the cooling surface (8A) is flattened by the brazing heat of the assembly. It is possible to prevent the degree from decreasing and the porous tube (21) from being deformed. Therefore, the flatness of the cooling surface (8A) can be kept high, and as a result, the adhesion with the insulating layer (3) can be improved and the semiconductor element (2) can be efficiently cooled. Further, the fine passage (21) can be held in a predetermined shape and size, and high cooling capacity can be exhibited. Furthermore, since the perforated tube (20) is accommodated in the case main body (10) and the cover plate (30) and further integrated by brazing, it has high mechanical strength. In addition, since the fret is filled in the gaps between the case body (10), the tube (20), and the lid plate (30), the thermal conductivity is good and an excellent cooling capacity can be obtained. it can.

  Further, the liquid cooling type cooling plate (8) includes a first connection port member (18a) connected to the coolant inlet pipe (19a) and a second connection port member connected to the coolant outlet pipe (19b). (18b), it is possible to easily connect the coolant inlet pipe (19a) and the coolant outlet pipe (19b) to the liquid cooling type cooling plate (8).

  Since the insulating layer and the heat dissipation device are integrally joined to the semiconductor element substrate according to the present invention, it is not necessary to attach the heat dissipation device in a separate process, and the manufacturing process is simplified. In addition, since the insulating layer and the heat dissipation device are directly joined, the thermal resistance is small and the cooling performance is excellent.

  The semiconductor element substrate (1A) (1B) and the semiconductor module (S1) (S2) of the present invention are mounted on an electronic product such as an electric vehicle or a computer to reliably cool the semiconductor element and to operate it for a long time. High reliability. Moreover, the life extension effect of a semiconductor element lifetime can also be acquired by cooling. As semiconductor modules, IGBT modules, inverters, converters, semiconductor control elements, diodes, capacitors, coils, light emitting components, semiconductor devices, multichip modules, speakers, CRTs, hard disk drives, DVD drives, printer components (example: thermal head) ), Or modules mounted on them. The term “electric vehicle” includes a hybrid vehicle, and examples of the vehicle include an automobile, a motorcycle, and a railway vehicle.

  As an example of use of the semiconductor module, an electric vehicle (40) equipped with the semiconductor module (S2) will be described with reference to FIG.

  The electric vehicle (40) is equipped with an existing radiator (41) for cooling the coolant. The radiator (41) is disposed at the front portion of the electric vehicle (40). Note that (44) is a radiator fan, and (45) is a wheel.

  A cooling liquid inflow pipe (19a) is connected to the first connection port member (18a) of the liquid cooling type cooling plate (8) of the semiconductor module (S2) in a liquid-tight state, and the liquid cooling type cooling plate ( The coolant outlet pipe (19b) is connected to the second connecting port member (18b) of 8) in a liquid-tight state. The coolant cooled by the radiator (41) flows through the coolant inlet pipe (19a). The cooling liquid discharged from the liquid cooling type cooling plate (8) flows through the cooling liquid outflow pipe (19b), and then the cooling liquid is supplied to the radiator (41).

  In the electric vehicle (40), the coolant cooled by the radiator (41) is liquid-cooled through the coolant inlet pipe (19a) by the pump (43) through the reserve tank (receiver tank) (42). Sent to the cooling plate (8). Then, as shown in FIG. 6, the coolant (C) flows into the first header part (14a) from the first connection port member (18a) of the liquid cooling type cooling plate (8), and branches into a large number. It flows through each fine passage (21) of the other hole tube (20). During this distribution, the cooling liquid (C) takes heat of the semiconductor element (2) and cools the semiconductor element (2). Thereafter, the coolant (C) flows into the second header portion (14b), joins at the second header portion (14a), and flows out from the second connection port member (18b). The coolant (C) that has flowed out is supplied to the radiator (41) through the coolant discharge pipe (19b), and is cooled again by the radiator (41).

  As described above, in the electric vehicle (40), the coolant (C) circulates through the radiator (41) and the liquid-cooled cooling plate (8) to reliably cool the semiconductor element (2) over a long period of time. Thus, high reliability can be ensured. Moreover, since an electric vehicle such as an electric vehicle has a water cooling mechanism, it is easy to apply a semiconductor module incorporating the liquid cooling type cooling plate of the present invention.

  A semiconductor element substrate (1B) and a semiconductor module (S2) shown in FIGS. In the semiconductor element substrates (1B) of Examples 1 to 11 shown in Table 1, the current-carrying layer (4) and the liquid-cooled cooling plate (8) are shared, and the configuration of the insulating layer (3) is shown in Table 1. Variously changed.

  As the conductive layer (4), a copper foil having a thickness of 70 μm was used.

  As described above, the liquid-cooled cooling plate (8) brazes a plurality of aluminum porous tubes (20) in an aluminum case body (10) and an aluminum lid plate (30). In addition, the first connecting port member (18a) and the second connecting port member (18b) are brazed. More specifically, the perforated tube (20) is an extruded tube having a height of 1.7 mm and a width of 16 mm in which 19 fine passages (21) are formed, and the equivalent diameter of the fine passage (21) is 0.7 mm. The wall thickness of the outer peripheral wall is 0.3 mm, and the wall thickness of the partition between the adjacent fine passages (21) and (21) is 0.2 mm. In this example, 12 such porous tubes (20) were used side by side. The case body (10) has a rectangular size of 100 mm × 200 mm, a height of 20 mm, a side wall thickness of 2 mm, and a tube receiving recess (12) forming portion of a thickness of 2 mm. ing. The lid plate (30) is a flat plate having a thickness of 3 mm. For the convenience of illustration, the numbers of perforated tubes and fine passages in the figure do not match those of this embodiment.

  Insulating layer (3) was formed of Examples 1 and 2 using only an insulating resin, and Examples 3 to 6 were formed of a resin composition in which a thermally conductive filler was blended into an insulating resin. In Examples 7 to 11, a glass fiber nonwoven fabric was used as the insulating fabric, and the glass fiber nonwoven fabric was formed of a composite material impregnated with an insulating resin or an insulating resin composition. Table 1 shows the insulating resin used in each example, the type and content of the thermally conductive filler, the thickness of the insulating fabric, and the thickness of each insulating layer formed. Moreover, these heat conductivity is shown.

Then, the current-carrying layer (4), insulating layer (3) and liquid-cooled cooling plate (8) described above are heated at 3.92 MPa (40 kgf / cm ² ) at 170 ° C. for 2 hours based on the hot-pressing method described above. The substrate for semiconductor element (1B) was manufactured by pressing and bonding.

  Table 1 shows the thermal resistance value of each semiconductor element substrate (1B) produced as described above.

  Further, the semiconductor element (2) was soldered to the semiconductor element substrate (1B) to produce a semiconductor module (S2).

Regarding the time-dependent warpage of the insulating layer (3), the maximum warpage amount D1 and the sample piece L1 of the maximum warpage portion were measured based on JIS C6481, and the warpage rate W1 (%) = D1 / L1 × 100 was obtained. . And it evaluated by the following reference | standard by the curvature rate W1.
◎: Less than 1% ○: 1-2%
×: More than 2% Further, as a comparative example, the copper foil as the current-carrying layer was joined to a ceramic insulating layer having a thickness of 3 mm, and the ceramic insulating layer was bonded to a liquid-cooled cooling plate (8). A substrate for a semiconductor element was manufactured by bonding to the substrate. Table 1 shows the thermal conductivity and thermal resistance of the comparative example.

  From the result of Table 1, it has confirmed that the board | substrate for semiconductor elements of each Example can exhibit the outstanding cooling capability. Moreover, it was confirmed that by using an insulating resin composition containing a thermally conductive filler as an insulating layer, the thermal conductivity can be increased and the cooling capacity can be improved. In addition, it was confirmed that the use of the insulating fabric can suppress the dimensional change of the insulating layer even when used for a long period of time.

  The substrate for a semiconductor device according to the present invention can be used as a substrate for cooling by mounting various heating elements including a semiconductor device for an electric vehicle and a semiconductor device for a computer.

It is a typical sectional view of a substrate for semiconductor elements and a semiconductor module concerning one embodiment of the present invention. FIG. 2 is a diagram (graph) showing a relationship between an equivalent diameter of a micro passage of a tube and a thermal resistance in the liquid cooling type cooling plate incorporated in the semiconductor element substrate of FIG. 1. It is a perspective view of the board | substrate for semiconductor elements concerning other embodiment of this invention. FIG. 4 is an exploded perspective view of a liquid cooling type cooling plate incorporated in the semiconductor element substrate of FIG. 3. It is the XX sectional view taken on the line in FIG. It is the YY sectional view taken on the line in FIG. FIG. 4 is a sectional view taken along line ZZ in FIG. 3. It is a schematic plan view of the electric vehicle carrying the semiconductor module in which the board | substrate for semiconductor elements of FIG. 3 was integrated. It is typical sectional drawing which shows the method of joining an electricity supply layer, an insulating layer, and a thermal radiation device. It is sectional drawing which shows the semiconductor module in which the conventional semiconductor element substrate and this semiconductor element substrate and the heat dissipation device were incorporated.

Explanation of symbols

1A, 1B ... Semiconductor device substrate
S1, S2 ... Semiconductor module
2 ... Semiconductor element
3… Insulating layer
4… Conducting layer
5… Heat dissipation device
7 ... Perforated tube (liquid cooling type cooling plate, heat dissipation device)
20 Perforated tube
7a, 21 ... Fine passage
8 ... Liquid-cooled cooling plate (heat dissipation device)
10 ... Case body
11a, 11b ... Header forming recess
12 ... Recess for tube accommodation
14a, 14b ... Header
18a ... 1st connection port member
18b ... Second connecting port member
30 ... Lid plate
40… Electric car (electric vehicle)
C ... Coolant

Claims (14)

  A substrate for mounting a semiconductor element, wherein a current-carrying layer for attaching the semiconductor element is formed on one side of the insulating layer, and a heat dissipation device is directly joined on the other side.   The semiconductor element substrate according to claim 1, wherein the heat dissipating device is a liquid cooling type cooling plate having a plurality of fine passages through which a coolant flows. The liquid cooling plate is
At least one flat porous tube having a fine passage through which a cooling liquid flows, two header portion forming recesses spaced apart from each other, and a tube that is formed between both header portion forming recesses and accommodates the tube A case main body provided with a housing recess, and a cover plate that is superposed on the case main body,
The porous tube is accommodated in the tube accommodating recess so as to communicate with both the header portion forming recesses, and the cover tube is superposed on the case body. While sandwiched between the lid plates, the opening portions of the header portion forming recesses are closed by the lid plate to form two header portions, and the case body, the porous tube, and the lid plate are The semiconductor element substrate according to claim 2, wherein the substrate is joined and integrated in a state of preventing leakage of a coolant flowing through the header portion.   In the liquid cooling type cooling plate, a first connection port member connected to the cooling liquid inflow pipe is connected to one of the two header parts and connected to the cooling liquid outflow pipe. The semiconductor element substrate according to claim 3, wherein the two connection port members are connected in communication with the other header portion.   5. The semiconductor element substrate according to claim 2, wherein an equivalent diameter of the micro passage of the liquid cooling type cooling plate is set in a range of 0.05 to 1.7 mm.   The semiconductor element substrate according to claim 1, wherein the insulating layer is made of an insulating resin.   The said insulating layer consists of an insulating resin composition which mix | blended the heat conductive filler with insulating resin, The board | substrate for semiconductor elements of any one of Claims 1-5.   The insulating layer is a composite material obtained by impregnating an insulating resin into an insulating fabric, or an insulating resin composition in which an insulating resin is blended with a heat conductive filler. The board | substrate for semiconductor elements of description.   The substrate for a semiconductor element according to claim 6, wherein the insulating resin is at least one of an epoxy resin and a polyimide resin. Wherein the thermally conductive _{filler, SiO 2, Al 2 O 3} , BeO, MgO, Si 3 N 4, at least one semiconductor device substrate according to claim 7 or 8 of the BN. 11. The substrate for a semiconductor element according to claim 7, wherein the content of the heat conductive filler in the insulating resin composition is 40 to 90% by volume.   A semiconductor module, wherein a semiconductor element is attached to the energization layer of the substrate for a semiconductor element according to claim 1.   An electric vehicle on which the semiconductor module according to claim 12 is mounted. A radiator is mounted, and the coolant cooled by the radiator flows into the liquid-cooled cooling plate, and the coolant flowing out from the liquid-cooled cooling plate is cooled by the radiator. 13. The electric vehicle according to 13.

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