JP2013233042A - Power semiconductor module, manufacturing method of the same, and semiconductor power conversion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power semiconductor device which achieves high reliability while having low heat resistance.SOLUTION: A first insulation resin sheet 101 is adhered to an adhered surface at a viscosity close to the minimum melt viscosity. Next, a second insulation resin sheet 102 is placed on the first insulation resin sheet 101, and an assembled structure is placed on the second insulation resin sheet 102. Then, these components are pressurized to be adhered to each other. At that time, a size of the second insulation resin sheet 102 is set to a size which is substantially the same as an outer shape of the assembly structure or slightly protrudes from the assembly structure. Next, a potting resin is injected until first to fourth conductors are buried including the exposed insulation resin sheet and is heated thereby thermally hardening the potting resin, the first resin sheet, and the second resin sheet.

Description

  The present invention relates to a semiconductor module that switches a large current.

In general, an electric vehicle and a hybrid vehicle include an inverter device as a power semiconductor device that converts direct current into alternating current and supplies the motor to a motor. For example, in the case of a three-phase inverter device, three independent modules corresponding to the U phase, the V phase, and the W phase are combined. Such an in-vehicle semiconductor power conversion device switches a large current of around 1000 amperes, and thus requires a structure that is small and lightweight and has high cooling efficiency.
For this reason, in the conventional structure, a structure in which both sides of a chip-like semiconductor switching element such as IGBT or GTO are cooled by one cooler has been proposed.

In the conventional structure shown in Patent Document 1, a semiconductor switching element is laid out in a direction perpendicular to the main plane of the cooler, and the semiconductor switching element is sandwiched between bus bars having a high thermal conductivity. The semiconductor switching element and the bus bar are electrically and mechanically connected by soldering. The periphery of the semiconductor switching element is sealed with resin.
A main plane different from the mounting surface of the semiconductor switching element of the bus bar is thermally connected to the cooler via an insulating sheet. As for the electrical connection, the main plane connected to the insulating sheet is taken out from another part.
The insulating sheet needs to have insulating properties but high thermal conductivity. For this reason, the resin sheet has a structure in which a thermosetting resin such as an epoxy resin in which a ceramic filler such as nitrogen boron is diffused is formed into a sheet shape.

JP 2010-16924 A

A metal bus bar is installed through a resin sheet containing a ceramic filler. However, if the filler filling rate is increased in order to lower the thermal resistance, the adhesive strength of the resin sheet tends to be weakened.
The bus bar expands and contracts due to the temperature rising and falling due to heat. When the adhesive force of the resin sheet is too weak, the adhesive surface between the resin sheet and the bus bar is peeled off by repeating such deformation, which may increase the thermal resistance.
On the other hand, if the filler filling rate is lowered in order to secure adhesive strength, the adhesiveness will improve, but the thermal conductivity of the resin sheet will deteriorate and the heat dissipation capability will not be increased, so the current value that can be passed through the semiconductor switching element Can no longer be raised.
On the other hand, it is possible to arrange a structure that presses and fixes the bus bar to the resin sheet so that the adhesive interface between the resin sheet and the bus bar does not peel off, but the structure that is not directly related to the function of such an inverter. Installation increases the weight and volume.
An object of the present invention is to provide a highly reliable semiconductor device even when a large current is handled with a simple configuration.

In order to achieve the above-described object, the present invention provides a pair of conductive heat conduction devices that are disposed opposite to each of the main surfaces of the semiconductor chip and electrically and mechanically connected to the semiconductor chip. A body and one main surface is bonded to the pair of conductive heat conductors so as to cover a semiconductor device between the pair of conductive heat conductors and the pair of conductive heat conductors A bonding interface between an insulating thermosetting resin sheet in which a conductive filler is dispersed and the one main surface of the thermosetting resin sheet surrounds the pair of conductive heat conductors. An envelope made of an insulating curable resin that seals the semiconductor chip, and a region of the thermosetting resin sheet that is bonded to the conductive block In the thickness direction rather than the density of the filler Towards the density of the parts side of the filler is to provide a high power semiconductor module.
At this time, it is preferable that the density of the filler on the back surface side is lower than the density of the filler on the surface on which the conductive block is bonded in the region not bonded to the conductive block.

  Further, the present invention provides a first thermosetting sheet formed in a sheet shape by a thermosetting resin disposed on a surface to be bonded and in which a filler made of an insulating material is dispersed. Pressurizing in the vicinity of the melting temperature to bond the bonded surface and the first thermosetting sheet, and a filler made of an insulating material is dispersed on the bonded first thermosetting sheet. The second thermosetting sheet formed into a sheet shape by the thermosetting resin is disposed, and the semiconductor chip and the main surface of the semiconductor chip are disposed opposite to each other on the second thermosetting sheet. A pair of conductive thermal conductors electrically and mechanically connected to the semiconductor chip are arranged and pressurized through the conductive block, and the first thermosetting sheet and the second thermosetting Sheet and the conductive block The step of adhering in a laminated state, and placing the thermosetting resin so as to include the pair of conductive heat conductors, and heat-curing to form an envelope, the semiconductor chip and the conductive heat conductor The manufacturing method of the power semiconductor module which comprises sealing and adhering the envelope and the insulating sheet is provided.

  The present invention contributes to providing a power semiconductor module having a simple structure and high reliability even when a large current is handled.

The schematic diagram which shows the power converter device of embodiment of this invention The circuit diagram of the power converter of the embodiment of the present invention The exploded view of the power semiconductor module of the embodiment of the present invention

FIG. 1 is a perspective view showing an inverter device, and FIG. 2 shows an equivalent circuit of the inverter device shown in FIG.
The inverter device 10 is configured as, for example, a U-phase, V-phase, and W-phase three-phase inverter, and is configured to supply power to, for example, the first motor 12 and the second motor 14 as load targets. ing. The inverter device 10 is integrally provided with a first system inverter circuit that supplies power to the first motor 12 and a second system inverter circuit that supplies power to the second motor 14.

  The inverter device 10 includes three power semiconductor modules 16, 18, and 20 corresponding to the U-phase, V-phase, and W-phase, respectively, and a smoothing that smoothes the DC voltage supplied from the DC power source, for example, the battery 22 to the power semiconductor module. Current detectors 28 and 30 for detecting the current flowing to the first motor 12 and the second motor via the capacitor 24, the three-phase output connection conductors 26 and 27, current information detected by the current detector, and a smoothing capacitor 24 for controlling the power semiconductor modules 16, 18, and 20 based on the voltage applied to 24, and for driving the gate of the semiconductor element of the power semiconductor module to be described later based on the control signal of the control unit 32. And a drive substrate 34 having a drive circuit.

  The driving substrate 34 is provided with driving ICs 36 for driving the semiconductor elements in a one-to-one correspondence with the semiconductor elements. That is, in this circuit, twelve driving ICs 36 are provided. Further, below the power semiconductor modules 16, 18, 20 and the smoothing capacitor 24, a cooler (not shown) such as a heat sink for cooling them is provided.

Hereinafter, the power semiconductor modules 16, 18, and 20 will be described in detail. Since the power semiconductor modules 16, 18, and 20 have the same configuration, the power semiconductor module 16 will be described as a representative.
FIG. 3 is an exploded perspective view of the power semiconductor module 16 with the cover removed.

The power semiconductor module of FIG. 3 includes semiconductor chips 41a to 41d, diode chips 51a to 51d combined with each of these semiconductor chips and connected in antiparallel, and electrodes of the semiconductor chips 41a to 41d and the diode chips 51a to 51d. Conductive thermal conductors 61 to 64 which are electrically and mechanically joined to the surface to form a rectangular bus bar, and semiconductor chips 41a to 41d and diode chips 51a to 51d of the rectangular conductive heat conductors 61 to 64 are joined. The conductive heat conductors 61 to 64 are joined to the cooling plane 67 formed by the cooler in a main surface that is different from the surface being formed and the surfaces formed by the conductors 61 to 64 are included in the same virtual plane. The insulating resin sheet 66 is in close contact with the semiconductor chips 41a to 41d, the diode chips 51a to 51d, and the conductive heat conductors 61 to 64. It is formed so as to cover Te and comprises an outer envelope (not shown) for restraining the deformation with sealing them.
The details will be described below.

  One side surface of the first conductor 61 forms a first joint surface 61a, and the other side surface orthogonal to the one side surface forms a second joint surface 61b. The first joint surface 61a of the first conductor 61 is electrically and mechanically joined to the positive side (collector and cathode, respectively) of the IGBT 41a and the diode 51a constituting the upper arm of the first system. The first joint surface 61a of the first conductor 61 is electrically and mechanically joined to the positive side (collector and cathode, respectively) of the IGBT 41c and the diode 51c that constitute the upper arm of the second system. Thereby, the 1st conductor 61 comprises the direct current | flow positive electrode conductor common to the semiconductor element of a 1st system | strain and a 2nd system | strain.

  On the first joint surface 61a, the IGBT 41a, the diode 51a, the IGBT 41c, and the diode 51c are arranged in a line along substantially the entire length in the longitudinal direction of the first conductor 61, and the IGBTs and the diodes are alternately arranged. Has been placed.

  One side surface of the second conductor 62 forms a first joint surface 62a, and the other side surface orthogonal to the one side surface forms a second joint surface 62b. The first joint surface 62a of the second conductor 62 is joined to the negative side (emitter and anode, respectively) of the IGBT 41b and the diode 51b constituting the lower arm of the first system, and the second conductor 62 is connected to the IGBT 41b and the diode 51b. It is electrically and mechanically connected to the negative electrode. The first joint surface 62a of the second conductor 62 is joined to the negative side (emitter and anode, respectively) of the IGBT 41d and the diode 51d constituting the lower arm of the second system, and the second conductor 62 is composed of the IGBT 41d and the diode. The electrode 51d is electrically and mechanically connected to the negative electrode. Thereby, the 2nd conductor 62 comprises the direct current | flow negative electrode conductor common to a 1st system | strain and a 2nd system | strain.

  On the first joint surface 62a, the IGBT 41b, the diode 51b, the IGBT 41d, and the diode 51d are arranged in a line along substantially the entire length in the longitudinal direction of the second conductor 62, and the IGBTs and the diodes are alternately arranged. Has been placed.

  The second conductor 62 is arranged in parallel with the first conductor 61 with a gap therebetween. The first joint surface 61a of the first conductor 61 and the first joint surface 62a of the second conductor 62 face each other in parallel with a gap. The second joint surface 61b of the first conductor 61 and the second joint surface 62b of the second conductor 62 are located side by side on the same plane.

  The IGBTs 41a and 41c joined to the first conductor 61 are disposed at positions shifted in the longitudinal direction of the first conductor with respect to the IGBTs 41b and 41d joined to the second conductor 62, and do not face the IGBTs 41b and 41d. The diodes 51b and 51d joined to the second conductor 62 are disposed opposite to each other. Similarly, the IGBTs 41b and 41d joined to the second conductor 62 are arranged to face the diodes 51a and 51c joined to the first conductor 61, respectively. In other words, as can be clearly understood from FIGS. 3 and 4, the IGBTs 41 a and 41 c joined to the first conductor 61 and the IGBTs 41 b and 41 d joined to the second conductor 62 are connected to the first and second conductors 61 and 62. Are arranged in a staggered pattern.

The third conductor 63 is disposed with a gap between the first conductor 61 and the second conductor 62. The third conductor 63 is arranged such that one end portion in the axial direction thereof is aligned with one end portion in the axial direction of the first and second conductors 61 and 62. Two opposing side surfaces of the third conductor 63 form two first joint surfaces 63 a, and these first joint surfaces 63 a are the first joint surface 61 a of the first conductor 61 and the first joint of the second conductor 62. The surfaces 62a face each other in parallel. Further, the other side surface orthogonal to the two side surfaces of the third conductor 63 forms a second bonding surface 63b. The second joint surface 63b is located in the same plane as the second joint surfaces 61b and 62b of the first and second conductors 61 and 62.
One joint surface 63a of the third conductor 63 is joined to the negative side (emitter and anode, respectively) of the IGBT 41a and the diode 51a constituting the upper arm of the first system, and the third conductor 63 is connected to the negative side of the IGBT 41a and the diode 51a. It is electrically and mechanically connected to the side electrode. The other first joint surface 63a of the third conductor 63 is joined to the positive side (collector and cathode, respectively) of the IGBT 41b and the diode 51b constituting the lower arm of the first system, and the third conductor 63 is composed of the IGBT 41b and the diode. The electrode 51b is electrically and mechanically connected to the positive electrode. Thereby, the 3rd conductor 63 comprises the alternating current electrode (output electrode) conductor of the 1st system | strain.

The fourth conductor 64 is arranged with a gap between the first conductor 61 and the second conductor 62, and further arranged in a line with the third conductor 63 with a gap. One end of the fourth conductor 64 in the axial direction is opposed to one end of the third conductor 63 with a gap, and the other end in the axial direction is aligned with the other end in the axial direction of the first and second conductors 61 and 62. Are arranged.
Two opposing side surfaces of the fourth conductor 64 form two first joint surfaces 64 a, and these first joint surfaces 64 a are the first joint surface 61 a of the first conductor 61 and the first joint of the second conductor 62. The surfaces 62a face each other in parallel. The other side surface orthogonal to the two side surfaces of the fourth conductor 64 forms a second bonding surface 64b. The second joint surface 64 b is located on the same plane as the second joint surfaces 61 b and 62 b of the first and second conductors 61 and 62.
One joint surface 64a of the fourth conductor 64 is joined to the negative side (emitter and anode respectively) of the IGBT 41c and the diode 51c constituting the upper arm of the second system, and the fourth conductor 64 is the negative electrode of the IGBT 41c and the diode 51c. It is electrically and mechanically connected to the side electrode. The other first joint surface 64a of the fourth conductor 64 is joined to the positive side (collector and cathode, respectively) of the IGBT 41d and the diode 51d constituting the lower arm of the second system, and the fourth conductor 63 is composed of the IGBT 41b and the diode. The electrode 51b is electrically and mechanically connected to the positive electrode. Thereby, the 4th conductor 64 comprises the AC electrode (output electrode) conductor of the 2nd system.
A groove-shaped notch 68 is formed on the upper surface of the fourth conductor 64, here, on the side surface opposite to the second bonding surface 64b. The notch 68 extends from one end to the other end along the axial direction of the fourth conductor 64.

  The bonding surfaces of the conductors described above and the IGBT and the diode can be bonded by solder or a conductive adhesive, or may be bonded via a thermal shock plate. The material of the first to fourth conductors 61, 62, 63, 64 is preferably copper from the viewpoint of heat transfer, but from the viewpoint of workability and weight, other metals such as aluminum, metals such as Al-SiC, etc. It is also possible to use composite materials.

The cooling plane 67 is one main surface formed by a metal rigid body, and provides a mounting surface for electrical components constituting the power semiconductor module. Second cooling surfaces 61b, 62b, 63b, and 64b of the first conductor 61, the second conductor 62, the third conductor 63, and the fourth conductor 64 are bonded and fixed to the cooling plane 67 by a sheet-like insulator 66.
The cooling plane 67 that functions as a heat dissipation path for heat generated by the electrical components is preferably formed of a metal having high heat conductivity such as copper or aluminum. The heat of the IGBT, the diode, and the first to fourth conductors is transferred to the outside of the power semiconductor module through this heat dissipation path to assist heat removal.
The cooling plane 67 is formed on the first joint surface 61 a of the first conductor 61, the first joint surface 62 a of the second conductor 62, the first joint surface 63 a of the third conductor 63, and the first joint surface 64 a of the fourth conductor 64. A surface to be joined that extends in a direction intersecting with each other, for example, an orthogonal direction, and is joined to the first, second, third, and fourth conductors via an insulator on the surface to be joined. At this time, the semiconductor elements of the IGBT and the diode are arranged so that the surfaces on the positive electrode side and the negative electrode side are not parallel to the surface of the cooling plane 67.
A heat conduction grease (not shown) is applied to the rear surface side of the heat radiating plate forming the cooling plane 67, and the heat radiating plate is fixed to a cooler (not shown) of the inverter device via the heat conduction grease by screws or the like. If assembly with thermal grease is not required, a cooling water channel may be provided inside the heat sink.

The insulating resin sheet 66 is an insulator having adhesiveness formed into a sheet shape. The insulating resin sheet 66 is a material having a sufficiently low rigidity with respect to the first to fourth conductors, and is made of, for example, an epoxy resin having adhesiveness in which a ceramic filler such as boron nitride is dispersed.
The insulating resin sheet 66 extends in a direction that further expands from a region including all the main surfaces on which the first to fourth conductors are arranged to face the cooling plane. That is, when the power semiconductor module is viewed from the normal direction of the surface formed by the cooling plane, the insulating resin sheet 66 exists so as to surround the first to fourth conductors.

  An envelope (not shown) is formed so that the first to fourth conductors and the semiconductor chip are buried in a region including the insulating resin sheet 66 that exists so as to surround the first to fourth conductors. The That is, the first to fourth conductors and the semiconductor chip are surrounded by the envelope and the insulating resin sheet and are not exposed.

Depending on the presence or absence of an envelope made of potting resin, the amount of strain of the structure composed of the first to fourth conductors is reduced by about 1/3, and this increases the life from 1000 cycles to 8000 cycles. Become. When the potting resin is peeled off, the amount of strain increases and the stress life due to the temperature gradient is shortened. Therefore, the cooler and the potting resin are not directly bonded.

For the shear test piece having a metal surface that simulates the cooling plane, when comparing the potting resin only, the insulating resin sheet + potting, and the adhesive strength of only the insulating resin sheet, the insulating resin sheet + potting and the insulating resin sheet alone It can be seen that the intensity is about 2.5 times stronger. Because potting resin alone has low adhesive strength. The envelope is not fixed, and the strain due to the deformation due to the temperature history of the internal structure cannot be suppressed. For this reason, it is necessary to have a structure in which the potting resin is not directly joined to the cooling plane.
In the power semiconductor module of this embodiment, the area of the insulating resin sheet is sufficiently wide, and the internal structure is surrounded by the bonding interface between the insulating resin sheet and the potting resin.

Here, the relationship between the filler filling rate and the adhesive force will be described. When the filler filling rate of the first insulating resin sheet 101 bonded to the cooler 67 is decreased, the interface adhesive force with the cooler 67 is increased. This indicates that by reducing the filler filling rate, the amount of epoxy resin, which is a component of adhesion, increases, so that the interfacial adhesive force increases. However, if the filler filling rate is lowered, the thermal resistance increases, so it is extremely difficult to determine the filler blending rate.
Therefore, the insulating resin sheet of the present embodiment uses an insulating resin sheet having a density configuration in which the density of the filler on the inner side is higher than the density of the filler on the surface side of the thermosetting resin sheet.

In order to realize this density configuration, a configuration in which insulating resin sheets having different filler filling rates are laminated on the front surface and the back surface, and a surface with a relatively low filler filling rate are arranged facing the metal surface, It was set as the structure which pressurizes and fuse | melts the surfaces with a high filler filling rate facing each other.
The first layer that is the surface of the first insulating resin sheet 101 that is bonded to face the cooling plane 67 is made to have a relatively low filler filling rate to enhance the adhesion, and the second layer of the first insulating resin sheet 101 is increased. The second layer serving as the surface to be bonded to the insulating resin sheet 102 is configured to have a larger filler filling rate than the first layer.
Similarly, the second insulating resin sheet 102 to be bonded to the first to fourth conductors 61, 62, 63, 64 has a low filler filling rate, and the first insulating resin sheet 101 The first layer serving as the surface to be bonded is made larger in filler filling rate than the second layer.

Since the size of the first insulating resin sheet 101 bonded to the cooling surface 67 is the same size as the cooling plate constituting the cooling surface, the cooling surface 67 is covered with the first insulating resin sheet 101. Therefore, the potting resin is structured to be bonded only to the insulating resin sheet.
As a result, the first and fourth conductors 61, 62, 63, and 64 are improved in adhesive force, and the envelope is firmly fixed on the surface having increased adhesive strength, so that it is sealed. It is possible to continue suppressing the distortion of the structure.

  The first to fourth conductors 61, 62, 63, 64, the first insulating resin sheet 101, the second insulating resin sheet 102, and the cooler 67 are bonded to each other under pressure and heating. The process will be described.

  First, the first insulating resin sheet 101 is bonded to the adherend surface in the vicinity of the minimum melt viscosity.

Next, the second insulating resin sheet 102 is placed on the first insulating resin sheet 101, and the first to fourth conductors 61, 62, 63, 64 and the semiconductor chip are further mounted on the second insulating resin sheet 102. The assembly structure to which is attached is mounted and pressed to adhere. At this time, the size of the second insulating resin sheet 102 is set to be approximately the same as the outer shape of the assembly structure or a size that protrudes somewhat. Although it may be smaller than the assembly structure, the heat radiation efficiency from the assembly structure is lowered, so it is set according to the product specifications.
Further, the outer peripheral edge of the second insulating resin sheet 102 is set so as to be all within the bonding surface of the first insulating resin sheet 101. That is, the outer peripheral edge of the second insulating resin sheet is overlapped so as to be surrounded by the first insulating resin sheet.

  Next, the potting resin, including the exposed insulating resin sheet, is injected until the first to fourth conductors are buried and heated, so that the potting resin, the first resin sheet 101, and the second resin sheet 102 are heated. Heat cure.

Thereby, in the resin sheet in the region not facing the first to fourth conductors 61, 62, 63, 64, the pressure resistance performance can be improved even if the resin sheet is not pressure-heat bonded.
This is because the first insulating resin sheet is first heated and pressure-bonded in the vicinity of the minimum melt viscosity, so that voids from the initial stage of the first insulating resin sheet can be crushed and removed outside the sheet, and the filler filler inside This is thought to be because the can be more precisely oriented.

The first insulating resin sheet can be heated and pressure-bonded first, so that it can be put evenly on the entire cooler 67, and a conductive heat conductor or envelope placed thereon. As a result, the pressure resistance can be improved.
The first to fourth conductors 61, 62, 63, 64 and the second insulating resin sheet 102 having a size limited to the area to be pressurized by the assembly structure are heated and pressure-bonded at the same time. The voids that could not be removed generated in the resin sheet that could not be received did not appear. Therefore, it is possible to completely bond the first to fourth conductors 61, 62, 63, 64 and the cooler 67 with the insulating resin sheet without reducing the withstand voltage.

  As described above, according to the power semiconductor module of the present embodiment, the cooler 67 and the potting resin are bonded via the first insulating resin sheet 101, thereby improving the adhesive strength of the potting resin and peeling off. By increasing the amount of strain caused by the above, the life of the temperature gradient is not lowered, and the filler filling rate of the layer bonded to the first to fourth conductors 61, 62, 63, 64 and the cooler 67 is reduced to reduce the adhesive strength. Thus, long-term reliability can be ensured without maintaining the adhesive force and reducing the cooling efficiency.

  In addition, the first insulating resin sheet 101 is first heated and pressure-bonded at the minimum melt viscosity, and another insulating resin sheet is laminated again on the region necessary for bonding and fixing the assembly structure, and then bonded. Therefore, the occurrence of voids at the end of the sheet generated from the inside of the resin sheet, which is a problem when crimping using a thick resin sheet to secure the adhesion and fixation of the assembly structure, which is a heavy object, and the resin sheet from the beginning It is possible to provide a power semiconductor module with high reliability against fatigue near the adhesive interface due to thermal strain while avoiding a decrease in breakdown voltage due to an initial void contained therein.

Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. You may combine suitably, such as adding a component or connecting two or more.
Therefore, for example, for the conductive heat conductor, in the embodiment, a rectangular block is used in consideration of the current procedure, heat dissipation, workability, etc., but it is formed by bending the plate stepwise depending on the design convenience Such a member may be used, and the orientation of the main surface of the semiconductor chip may be parallel or non-parallel to the non-joint surface.

  In each of the above-described embodiments, the IGBT is used as the switching element. However, another type of transistor, thyristor, or the like may be used. In each embodiment, the number of mounting IGBTs and diodes can be increased or decreased as necessary. The semiconductor element can be appropriately changed depending on the purpose and application of an object (for example, an electric vehicle) to which the semiconductor power conversion device is applied, and an optimal power capacity or the like can be selected. The semiconductor power conversion device is not limited to an inverter device that converts DC power into three-phase AC power, but can also be applied to an inverter device that converts DC power into single-phase AC power.

10: Inverter device, 12, 14 ... Motor,
16, 18, 20 ... power semiconductor module, 22 ... battery, 24 ... capacitor,
32 ... Control unit, 34 ... Drive board,
41a-41d ... IGBT, 51a-51d ... diode, 61 ... first conductor,
62 ... 2nd conductor, 63 ... 3rd conductor, 64 ... 4th conductor,
67 ... Radiating plate, 68 ... Notch, 71 ... Positive electrode DC output terminal,
72 ... Negative DC output terminal, 73 ... First AC output terminal, 74 ... Second AC output terminal,
78a, 78b, 78c, 78d ... emitter sense terminals,
101 ... 1st insulating resin sheet, 102 ... 2nd insulating resin sheet

Claims (4)

A semiconductor chip;
A pair of conductive thermal conductors disposed opposite to each of the main surfaces of the semiconductor chip and electrically and mechanically connected to the semiconductor chip;
Insulating filler bonded to the pair of conductive heat conductors so that one main surface covers the semiconductor device between the pair of conductive heat conductors and the pair of conductive heat conductors An insulating thermosetting resin sheet dispersed inside,
An envelope made of an insulating curable resin that is formed so that a bonding interface with the one main surface of the thermosetting resin sheet surrounds the pair of conductive heat conductors, and seals the semiconductor chip. And,
Of the thermosetting resin sheet, the power semiconductor module is characterized in that the density of the filler on the inner side in the thickness direction is higher than the density of the filler on the surface side in the region bonded to the conductive block. .   2. The power semiconductor according to claim 1, wherein the density of the filler on the back surface side is lower than the density of the filler on the surface on which the conductive block is bonded in a region not bonded to the conductive block. module. A first thermosetting sheet formed in a sheet shape by a thermosetting resin in which a filler made of an insulating material is dispersed is placed on the surface to be joined, and is applied in the vicinity of the minimum melting temperature of the thermosetting resin. Pressure and bonding the bonded surface and the first thermosetting sheet;
On the bonded first thermosetting sheet, a second thermosetting sheet formed in a sheet shape by a thermosetting resin in which a filler made of an insulating material is dispersed is disposed. On the curable sheet, a semiconductor chip and a pair of conductive heat conductors arranged to face each of the main surfaces of the semiconductor chip and electrically and mechanically connected to the semiconductor chip are arranged, and the conductive Pressing through a block and bonding the first thermosetting sheet, the second thermosetting sheet and the conductive block in a laminated state;
An envelope is formed by placing a thermosetting resin so as to include the pair of conductive heat conductors and then heat-curing to seal the semiconductor chip and the conductive heat conductor, and the envelope Bonding the insulating sheet to the insulating sheet;
A method for manufacturing a power semiconductor module, comprising: The power semiconductor module according to claim 1 or 2,
A drive circuit for driving the semiconductor device;
A semiconductor power conversion device comprising: a control circuit for controlling the semiconductor device.

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