JP2017084850A - Power semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power semiconductor device capable of downsizing while pressing with an even surface pressure.SOLUTION: A power semiconductor device comprises: a plurality of power semiconductor chips including a switching chip; a first chip metal member; a second chip metal member; a conductive cover plate provided at a first chip metal plate side; a plurality of spring members which are electrically connecting between the first chip metal member and the conductive cover plate, and presses the first chip metal member and the conductive cove plate in a direction separated away each other; a gate/emitter signal substrate electrically connected to the conductive cover plate; a signal terminal electrically connecting between a signal pad of the switching chip and the gate/emitter signal substrate; and supporting means having a plurality of holding parts which are the plurality of holding parts holding the spring members, are arranged in parallel in a region formed by a circumference of the electric semiconductor chip, and are formed in a direction vertical to a principal surface of the first chip metal member.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power semiconductor device having a pressure contact structure in joining power semiconductor chips.

  The power semiconductor device is a so-called pressure contact type high-power semiconductor module, and includes a conductive base plate, a conductive cover plate, a plurality of fixed module housing elements, and a plurality of semiconductor chips. The lower surface side of the semiconductor chip is connected to the base plate via the first electrode, and the upper surface side of the semiconductor chip is connected to the cover plate via the second main electrode and a plurality of contact elements that are flexible and press-contactable. (For example, see Patent Document 1).

  In the power semiconductor device described in Patent Document 1, the flexible individual press pin contact element includes a press contact spring and a current frame for energization, each having an independent shape. The contact element including the semiconductor chip is separated by a submodule housing element formed of polyamide resin.

  Further, in the power semiconductor device described in Patent Document 1, after the gate electrode of the switching chip is connected to the gate runner disposed beside the semiconductor chip through the wire bond contact, one shared gate signal It is the structure gathered by the conductor.

Japanese Patent No. 4280626

  However, the power semiconductor device described in Patent Document 1 has a contact element structure that uses an independent spring for press contact and a current frame for energization, and the amount of deflection of the current frame for energization is reduced by pressing. Since the distance between the contact elements of adjacent semiconductor chips cannot be ensured sufficiently, it is necessary to provide a wider interval between adjacent semiconductor chips. This is a structure not suitable for miniaturization of a semiconductor module.

  In addition, since the gate electrode, which is a signal electrode of the switching chip to be used, has a semiconductor module structure connected to the gate runner disposed between the chips through wire bond contact, the base plate area is large for wiring the gate runner. Therefore, the structure is not suitable for downsizing. In the structure in which the spring electric contact portion is used to connect the gate runner connecting the gates of the respective switching chips to the gate signal conductor, the spring electric contact portion needs to be provided separately, so that the size of the semiconductor module is increased. There is a problem.

  Furthermore, in the power semiconductor device described in Patent Document 1, a disc spring is generally used as a member that is provided between each semiconductor chip base plate and presses the semiconductor chip. However, since the disc spring has a hollow disk shape having an opening at the center, the surface pressure at the center and corners (four corners of the rectangular chip) of the semiconductor chip is reduced, and the semiconductor chip is uniform. The load could not be applied. For this reason, there is a possibility that the contact between the semiconductor chip and the base plate becomes unstable or the semiconductor chip is damaged due to the uneven load.

  The present invention has been made in view of the above, and an object thereof is to provide a power semiconductor device that can be miniaturized while being pressed with a uniform surface pressure.

  In order to solve the above-described problems and achieve the object, a power semiconductor device according to the present invention includes a plurality of power semiconductor chips including a switching chip, and a first chip metal provided on one of the power semiconductor chips. A member, a second chip metal member provided on the other side of the power semiconductor chip, a conductive cover plate provided on the first chip metal member side with respect to the power semiconductor chip, and the first chip metal A plurality of spring members for electrically connecting the member and the conductive cover plate and pressing the first chip metal member and the conductive cover plate away from each other; and under the conductive cover plate And a gate / emitter signal substrate electrically connected to the conductive cover plate, and a signal pad of the switching chip; A plurality of holding portions that form a hollow space for holding the spring member, and a signal terminal for electrically connecting the gate / emitter signal substrate, the outer periphery of the power semiconductor chip; And a support means having a plurality of holding portions arranged in parallel in a region formed and formed in a direction perpendicular to the main surface of the first chip metal member.

  In the power semiconductor device according to the present invention, in the above invention, the spring member includes a pressing spring that presses the first chip metal member and the conductive cover plate away from each other, and the first chip. And a conductive spring electrically connecting the metal member and the conductive cover plate.

  The power semiconductor device according to the present invention is characterized in that, in the above invention, the spring member has a surface subjected to conductive metal plating.

  In the power semiconductor device according to the present invention, in the above invention, each of the plurality of spring members is any one selected from a rectangular coil spring, a round coil spring, and a leaf spring. It is characterized by.

  In the power semiconductor device according to the present invention, in the above invention, the support means is a prismatic support member having insulation and provided on the first chip metal member. The member is provided on a side in contact with the first chip metal member, and has a recess that forms a hollow space having the same shape as the outer edge of the first chip metal member.

  In the power semiconductor device according to the present invention, in the above invention, the support means has an insulating property and has a prismatic support member provided on the first chip metal plate, and the support member. And a plurality of bosses each extending from the end of the first boss and capable of holding the first chip metal member.

  In the power semiconductor device according to the present invention, in the above invention, the support means includes a first conductive support member that supports the spring member and an insulating second member that supports the signal terminal. And a supporting member.

  In the power semiconductor device according to the present invention, in the above invention, the support means includes a first conductive support member that supports the spring member and an insulating second member that supports the signal terminal. The first support member is formed integrally with the first chip metal member.

  In the power semiconductor device according to the present invention as set forth in the invention described above, the gate / emitter signal substrate is electrically connected to the signal pads of all the switching chips via the signal terminals. It is characterized by.

  The power semiconductor device according to the present invention includes a plurality of the signal terminals in the above invention, wherein the plurality of signal terminals include a gate signal terminal in the switching chip and a switching chip. And a signal terminal for an emitter.

  A power semiconductor device according to the present invention is provided between the conductive cover plate and the gate / emitter signal substrate in the above invention, wherein the conductive cover plate and the gate / emitter signal are provided. The semiconductor device further includes a metal ball that transmits an emitter signal to and from the substrate, and the signal terminal transmits a gate signal in the switching chip.

  The power semiconductor device according to the present invention is characterized in that, in the above invention, the gate / emitter signal substrate is formed of a printed circuit board having two or more layers, or a laminate substrate through an insulating layer.

  In the power semiconductor device according to the present invention, in the above invention, a conductive base plate provided on the second chip metal member side with respect to the plurality of power semiconductor chips, and fixed to the conductive base plate. A sealing resin filled in a part of a hollow space formed by one or a plurality of inner resin frames separating the plurality of power semiconductor chips, the conductive base plate and the inner resin frame And further comprising.

  In the power semiconductor device according to the present invention as set forth in the invention described above, the inner resin frame is made of a high-strength resin having therein a yarn made of continuous high-strength fibers.

  In the power semiconductor device according to the present invention as set forth in the invention described above, the inner resin frame is made of a high-strength resin having a shock absorber rubber sheet therein.

  In the power semiconductor device according to the present invention as set forth in the invention described above, the inner resin frame is made of a high-strength resin having a cloth made of resin-impregnated high-strength fibers inside.

  In the power semiconductor device according to the present invention as set forth in the invention described above, the inner resin frame is made of high-strength resin having a metal plate therein.

  The power semiconductor device according to the present invention is characterized in that, in the above invention, a gap is provided between the conductive cover plate and the inner resin frame in a natural state.

  The power semiconductor device according to the present invention is characterized in that, in the above-mentioned invention, an outer resin frame is provided around the conductive cover plate.

  According to the present invention, it is possible to reduce the size while pressing with a uniform surface pressure.

FIG. 1 is a partial cross-sectional view showing a configuration of a power semiconductor device according to a first embodiment of the present invention. FIG. 2 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the first embodiment of the present invention. FIG. 3 is a cross-sectional view showing a configuration of a main part of the power semiconductor device according to the first embodiment of the present invention. FIG. 4 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the first embodiment of the present invention. FIG. 5 is a plan view showing a configuration of a main part of the power semiconductor device shown in FIGS. FIG. 6 is a schematic diagram showing an example of a configuration of a main part of the power semiconductor device shown in FIGS. FIG. 7 is a schematic diagram illustrating a configuration of a main part of the power semiconductor device according to the first modification of the first embodiment of the present invention. FIG. 8 is a schematic diagram illustrating a configuration of a main part of the power semiconductor device according to the second modification of the first embodiment of the present invention. FIG. 9 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the third modification of the first embodiment of the present invention. FIG. 10 is a cross-sectional view illustrating a configuration of a main part of the power semiconductor device according to the third modification of the first embodiment of the present invention. FIG. 11: is a fragmentary sectional view which shows the structure of the power semiconductor device concerning Embodiment 2 of this invention. FIG. 12 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the third embodiment of the present invention. FIG. 13: is a fragmentary sectional view which shows the structure of the power semiconductor device concerning Embodiment 4 of this invention. FIG. 14 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the fifth embodiment of the present invention. FIG. 15 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the sixth embodiment of the present invention. FIG. 16 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the seventh embodiment of the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by the following embodiment. The drawings referred to in the following description only schematically show the shape, size, and positional relationship so that the contents of the present invention can be understood. That is, the present invention is not limited only to the shape, size, and positional relationship illustrated in each drawing.

(Embodiment 1)
FIG. 1 is a partial cross-sectional view showing a configuration of a power semiconductor device according to a first embodiment of the present invention. 2 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the first embodiment of the present invention, and is a partial cross-sectional view taken along the line AA shown in FIG. In addition, the electrotherapy semiconductor device shown in FIGS. 1 and 2 is a diagram illustrating a use state, in which a load is applied to a conductive cover plate described later. The power semiconductor device is a power semiconductor device using a plurality of power semiconductor chips such as a switching chip and a free wheel diode chip, and a plurality of springs for pressure contact between each chip and the conductive cover plate. Are disposed vertically, and in the power semiconductor device using the switching chip, a signal spring is disposed in addition to the pressure contact spring, and one end of the signal spring is disposed on the switching chip. The other end is connected to a gate / emitter signal substrate disposed under the conductive cover plate, and each chip is fixed to the conductive base plate and has a high impact resistance. It is a structure separated individually by a resin frame. The power semiconductor device may use one power semiconductor device or a plurality of power semiconductor devices may be stacked.

  A power semiconductor device 1 shown in FIGS. 1 and 2 includes a substantially flat conductive base plate 2 and a substantially flat conductive cover plate 3. The conductive base plate 2 is provided with a free wheel diode chip 4 and a switching chip 5. Each of the freewheel diode chip 4 and the switching chip 5 has a plate shape. The freewheel diode chip 4 and the switching chip 5 are each provided with a lower chip metal plate 6 (second chip metal member) on the surface on the conductive base plate 2 side. The freewheel diode chip 4 and the switching chip 5 are each provided with an on-chip metal plate 7 (first chip metal member) on the surface opposite to the conductive base plate 2 side. The main electrodes 4a and 5a provided on the switching chip 5 are electrically connected. The under-chip metal plate 6 and the on-chip metal plate 7 may have a plate shape or a prismatic shape, and the plate thickness can be appropriately designed.

  The on-chip metal plate 7 is provided with a support member 10 that holds a spring member 8 including at least a pressure contact spring and an energizing spring on the side opposite to the free wheel diode chip 4 and the switching chip 5 side. Specifically, in the on-chip metal plate 7, the support member 10 provided on the side opposite to the free wheel diode chip 4 side holds a spring member 8 including a pressure contact spring, and the switching chip 5 side. The support member 10 provided on the opposite side holds a spring member 8 including a pressure contact spring and a signal terminal 9.

  The support member 10 has a flat plate shape in which a plurality of holding holes 101 and 102 for holding the spring member 8 and the signal terminal 9 are formed. The support member 10 has a recess 103 that can accommodate the upper surface of the on-chip metal plate 7 on the surface that contacts the on-chip metal plate 7. The plurality of holding holes 101 extend perpendicularly to the upper surface of the on-chip metal plate 7 and are arranged in parallel, and in a projection region extending from the upper surface of the on-chip metal plate 7, that is, the freewheel diode chip 4. The switching chip 5 (or the main electrodes 4a, 5a) is formed inside the shape formed by the outer edge.

  FIG. 3 is a cross-sectional view showing the configuration of the main part of the power semiconductor device according to the first embodiment of the present invention, and the on-chip metal body 7 and the support member 10 corresponding to the line BB shown in FIG. FIG. The recess 103 is preferably formed with an opening having the same shape as the shape formed by the outer edge of the on-chip metal plate 7 and may have a shape that can be fitted. Thereby, the positioning accuracy of the metal plate 7 on the chip with respect to the support member 10 when the metal plate 7 on the chip is fitted in the recess 103 can be improved, and the shift of the support member 10 with respect to the metal plate 7 on the chip can be prevented. . In addition, it is possible to prevent positional displacement between the plurality of spring members 8 and the on-chip metal plate 7, and it is possible to easily obtain a uniform contact pressure.

  The support member 10 is inserted into the plurality of holding holes 101 described above, and the spring member 8 and the signal terminal 9 are inserted into the upright metal plate 7, that is, on the main surface of the on-chip metal plate 7. On the other hand, the spring member 8 and the signal terminal 9 are arranged in parallel at a predetermined interval on the metal plate 7 on the chip by aligning them in the longitudinal direction by maintaining the state of extending substantially vertically. As a material constituting the support member 10, a thermosetting resin, a thermoplastic resin molded product, or a material obtained by processing a ceramic plate is used. Costs can be reduced by using thermosetting resins and thermoplastic resin moldings, and dimensional accuracy against temperature is superior to thermosetting resins and thermoplastic resin moldings by using ceramic plate processed products. Therefore, the positional accuracy of the spring member 8 and the signal terminal 9 with respect to each power semiconductor chip (freewheel diode chip 4 and switching chip 5) is improved. Here, the “main surface” is a surface that contacts the spring member 8 and the signal terminal 9, and in the case of a plate-shaped or prism-shaped member, it is a plurality of surfaces that constitute the surface of the member. A surface having a large area.

  FIG. 4 is a plan view showing a configuration of a main part of the power semiconductor device shown in FIGS. 1 and 2 and explaining the configuration of the switching chip 5. A main electrode 5 a and gate / emitter electrodes 5 b and 5 c are provided on the main surface of the switching chip 5. The main electrode 5 a is in contact with the spring member 8, and the gate / emitter electrodes 5 b and 5 c are in contact with the signal terminal 9. As shown in FIG. 1, the signal terminal 9 is in contact with the electrode pads 11a and 11b formed on the gate / emitter signal substrate 11 provided on the conductive cover plate 3, and the gate / emitter electrode 5b. 5c and the electrode pads 11a and 11b are electrically connected to each other.

  The power semiconductor device 1 includes a plurality of inner resin frames 12 erected from the conductive base plate 2 between the freewheel diode chip 4 and the switching chip 5. A part of the space formed by the plurality of inner resin frames 12 and the conductive base plate 2 is filled with a sealing resin 14.

  The free wheel diode chip 4 and the switching chip 5 are individually separated by an inner resin frame 12 fixed to the conductive base plate 2, and the inner resin frame 12 is filled with a sealing resin 14 to an arbitrary height. ing.

  By individually enclosing each freewheel diode chip 4 and switching chip 5 with the inner resin frame 12, even if each chip is short-circuited, it does not affect adjacent chips. Furthermore, the insulation can be secured by sealing with the sealing resin 14. Examples of the material used as the sealing resin 14 include general insulating sealing resins such as a silicone gel resin and an epoxy resin.

  In addition, outer resin frames 13 extending in a direction orthogonal to the main surface are provided at both ends of the conductive cover plate 3. By installing the outer resin frame 13 on the conductive cover plate 3, an effect of further improving the explosion-proof property can be obtained.

  The inner resin frame 12 and the conductive cover plate 3 were applied between the conductive base plate 2 and the conductive cover plate 3 in a use state, that is, a state in which a load is applied to the conductive cover plate 3 from the outside. In this state, the inner resin frame 12 abuts on the conductive cover plate 3 and functions as a stopper that regulates the amount of movement of the conductive cover plate 3 so that the conductive cover plate 3 and the support member 10 do not come into contact with each other. . At this time, a load by the spring member 8 is applied between the conductive cover plate 3 and the on-chip metal plate 7.

  FIG. 5 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the first embodiment of the present invention, in which a load other than gravity is not applied to the conductive cover plate 3. The inner resin frame 12 and the conductive cover plate 3 are provided with an arbitrary interval in a natural state, that is, in a state where a load other than gravity is not applied to the conductive cover plate 3. That is, in the natural state, a pressure is applied between the conductive base plate 2 and the conductive cover plate 3 by the spring member 8, and the conductive cover plate 3 and the inner resin frame 12 are separated from each other. In the natural state, the conductive base plate 2 and the conductive cover plate 3 are held at a uniform distance by the spring member 8.

  In the first embodiment, the plurality of spring members 8 are constituted by springs having two types of functions of a pressing spring and an energizing spring. As described above, as the plurality of spring members 8, a spring that applies a uniform pressing force to the free wheel diode chip 4 and the switching chip 5 and flows a predetermined current between the conductive base plate 2 and the conductive cover plate 3 is used. As a result, it is possible to arbitrarily change the energization current with the same number of springs for the free wheel diode chip 4 and the switching chip 5 to be used, thereby simplifying the circuit design.

  FIG. 6 is a schematic diagram illustrating a configuration of a main part of the power semiconductor device illustrated in FIGS. 1 and 2, and illustrates an example of a configuration of the spring member 8. The spring member 8 is realized by using, for example, a rectangular coil spring formed by winding a wire having a rectangular cross section with a plane orthogonal to the longitudinal direction as shown in FIG.

  The plurality of spring members 8 can be used as springs that collectively have the functions of a pressing spring and an energizing spring that have been subjected to conductive metal plating, for example, by performing conductive metal plating on the surface. While applying a pressing force by the kind of spring member 8, it is possible to flow a predetermined current. Note that two types of springs (two types of springs having a conductive function and a pressing function that are independent of each other), ie, a pressing spring plated with conductive metal and an energizing spring, may be used.

  Also for the signal terminal 9, a rectangular coil spring similar to the spring member 8 can be used. The signal terminal 9 has a function of one of two types of signal wires for gate and emitter in the switching chip 5 according to the electrode to be connected (see FIG. 2). By using the signal terminal 9 having a gate function or an emitter function for the switching chip 5, the effect of improving the individual chip operation reliability can be obtained. Further, the power semiconductor device 1 can be miniaturized by arranging the signal terminal 9 directly above the switching chip 5 and connecting it to the gate / emitter signal substrate 11. Although the lead wire shape with a crimping function may be used as the signal terminal 9, the lead wire shape with the crimping function has a disadvantage that the wiring length is short and noise can be reduced, but the joint shape is complicated. is there.

  Note that the above-described Patent Document 1 specifies the gate signal extraction structure from each switching chip, but does not specify the emitter signal extraction structure.

  In the first embodiment, it is assumed that the signal terminal 9 functions as either a gate or an emitter, and a plurality of signals are provided. However, in the switching chip 5, a hole for the signal terminal 9 is provided. The signal terminal 9 is integrally formed, and is connected to the gate / emitter electrodes 5b and 5c of the switching chip 5 at one end, and the electrode of the gate / emitter signal substrate 11 disposed on the conductive cover plate 3 at the other end. It may be connected to the pads 11a and 11b. Thereby, signal wiring can be performed in a lump, and the power semiconductor device 1 can be reduced in size by wiring directly above the switching chip 5.

  According to the first embodiment described above, a uniform pressing force is applied to the freewheel diode chip 4 and the switching chip 5 by the plurality of spring members 8, and a predetermined current is applied between the conductive base plate 2 and the conductive cover plate 3. In addition, the switching chip 5 and the gate / emitter signal substrate 11 are electrically connected by the signal terminal 9, so that the electrical connection between the switching chip 5 and the gate / emitter signal substrate 11 is performed. Compared to the case of using an individual press pin contact element in which the spring for press contact and the current frame for energization are each configured independently, The power semiconductor device can be reduced in size while being pressed with a uniform surface pressure.

  Further, according to the first embodiment, by using the spring member 8 on which conductive metal plating is performed, it becomes possible to simultaneously realize the pressing effect and the energizing effect with one type of spring, and the power semiconductor device can be made compact. Can be realized.

  Further, according to the first embodiment, by using the support member 10 in which the plurality of holding holes 101 are formed, the vertical pressure can be obtained without the spring members 8 buckling, and each power semiconductor chip. The contact reliability between the under-chip metal plate 6 and the on-chip metal plate 7 is improved, and the electrical reliability is improved, for example, the contact resistance is reduced.

  Further, according to the first embodiment, the supporting member 10 is made insulative, so that weight reduction can be achieved at low cost.

(Modification 1 of Embodiment 1)
FIG. 7 is a schematic diagram illustrating a configuration of a main part of the power semiconductor device according to the first modification of the first embodiment of the present invention, and is a diagram illustrating another example of the configuration of the spring member. In the first embodiment described above, the spring member 8 and the signal terminal 9 have been described as being a rectangular coil spring formed by winding a wire having a rectangular cross-section with a plane orthogonal to the longitudinal direction. However, as in the spring member 8a shown in FIG. 7, a round wire coil spring formed by winding a wire having a circular cross section with a plane perpendicular to the longitudinal direction as a cut surface may be used.

(Modification 2 of Embodiment 1)
FIG. 8 is a schematic diagram illustrating a configuration of a main part of the power semiconductor device according to the second modification of the first embodiment of the present invention, and is a diagram illustrating another example of the configuration of the spring member. In the first embodiment described above, the spring member 8 and the signal terminal 9 have been described as being a rectangular coil spring formed by winding a wire having a rectangular cross-section with a plane orthogonal to the longitudinal direction. However, like the spring member 8b shown in FIG. 8, a strip-shaped material may be used, and the leaf | plate spring which makes the shape curved along the main surface may be sufficient. The belt-shaped material used for the spring member 8b may be a material having a uniform width and a uniform plate thickness. In addition, a width | variety refers to the length of the direction orthogonal to a longitudinal direction in the main surface of a strip | belt-shaped member.

  The various spring members described above can be appropriately selected according to the required function. For example, in general, a spring member 8 that is a square coil spring is preferably used to obtain a high pressure, and a spring member 8a that is a round wire coil spring is preferably used for downsizing, and a high current is obtained. When flowing, the spring member 8b, which is a leaf spring having a large cross-sectional area, is preferably used, and can be arbitrarily selected from the required pressing force value, energization current value, and size. Various spring members may be used alone or in combination. Further, both ends of the spring members 8 and 8a may be polished to form seat portions (seat surface polishing).

(Modification 3 of Embodiment 1)
In the first embodiment described above, the concave portion 103 is described as forming a closed region that forms a hollow space into which the on-chip metal plate 7 can be fitted. However, instead of the concave portion 103, the end portion of the support member 10 is used. A plurality of bosses protruding intermittently from the upper surface of the metal plate 7 on the chip may be provided according to the outer edge shape, and the metal plate 7 on the chip may be held by the plurality of bosses.

  FIG. 9 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the third modification of the first embodiment of the present invention. FIG. 10 is a cross-sectional view showing the configuration of the main part of the power semiconductor device according to the third modification of the first embodiment of the present invention, which is an on-chip metal body 7 corresponding to the CC line shown in FIG. FIG. 3 is a view showing a cross section of the support member 10. In the third modification, instead of the above-described recess 103, as shown in FIGS. 9 and 10, a plurality of bosses 104 extending from the end of the support member 10 are provided. In the third modification, the on-chip metal plate 7 is held by the plurality of bosses 104. When the end surface of the on-chip metal body 7 is rectangular, for example, as shown in FIG. 10, the plurality of bosses 104 are respectively provided at positions corresponding to the central portion of each side. In addition, a pin may be provided on the support member 10 and a hole portion in which the pin can be inserted and removed is provided on the metal plate 7 on the chip to be positioned.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. FIG. 11: is a fragmentary sectional view which shows the structure of the power semiconductor device concerning Embodiment 2 of this invention. In addition, the same code | symbol is attached | subjected to the same component as the component mentioned above in FIG.

  The power semiconductor device 1a shown in FIG. 11 includes an on-chip metal plate 7a and a support member 10a in place of the on-chip metal plate 7 and the support member 10 with respect to the configuration of the power semiconductor device 1 described above.

  The on-chip metal plate 7a is formed using a conductive material. In the on-chip metal plate 7a, a plurality of holding holes 71 each having a bottomed cylindrical shape capable of holding a plurality of spring members 8 are formed. The holding hole 71 has a depth that is at least shallower than the length of the spring member 8 in the natural direction (direction extending by winding). The on-chip metal plate 7 a only needs to be electrically connected between the conductive base plate 2 and the conductive cover plate 3 by the spring member 8, and at least the wall surface of the holding hole 71 that holds the spring member 8 has conductivity. At the same time, it is only necessary that the holding hole 71 and the main electrodes 4a and 5a are electrically connected. The on-chip metal plate 7a holds the spring member 8 in the holding hole 71 so that the spring member 8 is maintained upright with respect to the on-chip metal plate 7a. In the second embodiment, the on-chip metal plate 7a functions as a first chip metal plate and a first support member that are integrally formed.

  The support member 10a (second support member) is formed using an insulating material. A holding hole 102 for holding the signal terminal 9 is formed in the support member 10a. The support member 10a is attached to the on-chip metal plate 7a according to the arrangement of the signal terminals 9, that is, the arrangement of the gate / emitter electrodes 5b and 5c of the switching chip 5. The support member 10a is formed using the same material as the support member 10 described above.

  According to the second embodiment described above, by using the conductive on-chip metal plate 7a as the member for holding the spring member 8, the electrical conductivity and the thermal conductivity are improved. Since heat during operation of the freewheel diode chip 4 and the switching chip 5) can be efficiently propagated to the conductive cover plate 3, temperature rise due to heat generation of each power semiconductor chip can be reduced. The resistance between each power semiconductor chip and the conductive cover plate 3 is reduced, the heat generation of the spring member 8 can be reduced, and the reliability of the spring member 8 is improved.

  Further, according to the second embodiment described above, since the holding member that holds the plurality of spring members 8 is the on-chip metal plate 7a integrated with the on-chip metal plate, as described above, the electrical conductivity, Thermal conductivity is improved, and the reliability of electrical connection between each power semiconductor chip and the spring member 8 is improved.

  Furthermore, according to the second embodiment described above, the spring member 8 may be inserted into the holding hole 71 of the on-chip metal plate 7a, so that there is an advantage that the assembly can be simplified.

  In the second embodiment described above, the support means for supporting the spring member 8 has been described as being provided integrally with the on-chip metal plate, but may be a separate body. In the case of a separate body, for example, a portion including the holding hole 71 may be formed as a conductive support member (first support member).

(Embodiment 3)
Next, a third embodiment of the present invention will be described. FIG. 12 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same component as the component mentioned above in FIG.

  A power semiconductor device 1 b shown in FIG. 12 includes an inner resin frame 12 a instead of the inner resin frame 12 in the configuration of the power semiconductor device 1 described above. A thread 15 made of continuous high-strength fibers is provided inside the inner resin frame 12a. Examples of the material constituting the yarn 15 include polyamide, polyamideimide, polyimide, carbon, engineering plastic fiber, and the like, and an insulating material is preferable.

  The diameter of the yarn 15 is preferably φ50 microns or more from the viewpoint of tensile strength. Furthermore, the continuous shape of the yarn 15 from one end to the other end is superior in the explosion resistance of the inner resin frame 12a.

  As a method of manufacturing the inner resin frame 12a including the yarn 15, first, the yarn 15 is multiply arranged in a mold, and then integrally molded with a molding resin to obtain the inner resin frame 12a.

  According to the third embodiment described above, since the free wheel diode chip 4 and the switching chip 5 are separated by the inner resin frame 12a including the thread 15, each power semiconductor chip (the free wheel diode chip 4 and the switching chip) is separated. Even when the chip 5) is short-circuit broken, the explosion resistance of the inner resin frame 12a is further improved, so that damage to other semiconductor chips that are not short-circuit broken can be prevented.

  Here, the realization of impact resistance by a module housing element (resin frame) made of a synthetic material reinforced with long fibers having high impact strength is, for example, about 0.1 mm as a minimum in Patent Document 1 described above. Although it is disclosed that a synthetic member reinforced with long fibers having a diameter of 5 mm is used, if the fiber length is too long, the impact resistance is increased, but the fluidity at the time of molding of the molded resin is lowered, and the molded product However, there is a problem in that the fiber length is limited because a manufacturing problem such as inability to mold occurs. On the other hand, in this Embodiment 3, since the thread | yarn 15 is provided inside the inner side resin frame 12a, a moldability can be improved.

  Furthermore, the module housing element in Patent Document 1 described above is only the module housing element installed on the outer periphery of a plurality of semiconductor chips, and no material having impact resistance is used for the sub module housing element. When a semiconductor chip explodes, there is a problem that all the semiconductor chips arranged in one module housing element are damaged by the explosion shock. On the other hand, in the third embodiment, since the free wheel diode chip 4 and the switching chip 5 are separated by the inner resin frame 12a, damage to other semiconductor chips can be prevented.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. FIG. 13: is a fragmentary sectional view which shows the structure of the power semiconductor device concerning Embodiment 4 of this invention. In addition, the same code | symbol is attached | subjected to the same component as the component mentioned above in FIG.

  A power semiconductor device 1 c shown in FIG. 13 includes an inner resin frame 12 b instead of the inner resin frame 12 in the configuration of the power semiconductor device 1 described above. A shock absorber rubber sheet 16 is provided inside the inner resin frame 12b. The impact-absorbing material rubber sheet 16 is formed using a sheet made of a material having a low elastic modulus such as a silicone rubber sheet, a silicone gel sheet, a nitrile rubber sheet, etc., and it is shock-absorbing to use a sheet having a thickness of 1 mm or more. From the viewpoint of Further, as a method of manufacturing the inner resin frame 12b including the shock absorber rubber sheet 16, first, the shock absorber rubber sheet 16 is multiply arranged in the mold, and then integrally molded with a molding resin, and the inner resin frame 12b is formed. Get.

  According to the fourth embodiment described above, since the free wheel diode chip 4 and the switching chip 5 are separated by the inner resin frame 12b including the shock absorber rubber sheet 16, each power semiconductor chip (free wheel diode) Even when the chip 4 and the switching chip 5) are short-circuit broken, the shock is absorbed by the shock absorber rubber sheet 16, and the explosion resistance of the inner resin frame 12b is further improved, so that other semiconductor chips that are not short-circuit broken are damaged. Damage can be prevented.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described. FIG. 14 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the fifth embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same component as the component mentioned above in FIG.

  A power semiconductor device 1 d shown in FIG. 14 includes an inner resin frame 12 c instead of the inner resin frame 12 in the configuration of the power semiconductor device 1 described above. Inside the inner resin frame 12c, a cloth 17 made of resin-impregnated high-strength fibers is provided. The cloth 17 is formed using reinforcing fibers such as an aramid cloth, a liquid crystal polymer cloth, a polyimide cloth, and a carbon fiber cloth that are used in bulletproof vests. In addition, as the resin impregnating the cloth 17, a thermosetting resin such as an epoxy resin or a polyimide resin, or a thermoplastic resin such as PPS (Polyphenylenesulfide) or PET (Polyethylene terephthalate) is used.

  The impact resistance is improved by using a plurality of the cloths 17 in an overlapping manner. The cloth 17 is woven by a general plain weave or satin weave. Further, as a method of manufacturing the inner resin frame 12c including the cloth 17, first, the cloth 17 is multiply arranged in a mold, and then integrally molded with a molding resin to obtain the inner resin frame 12c.

  According to the fifth embodiment described above, since the free wheel diode chip 4 and the switching chip 5 are separated by the inner resin frame 12c including the cross 17, each power semiconductor chip (the free wheel diode chip 4 and the switching chip) is separated. Even when the chip 5) is short-circuit broken, by incorporating the cloth 17 made of resin-impregnated high-strength fibers, the shock is absorbed and the explosion-proof property of the inner resin frame 12c is further improved. It is possible to prevent damage to the semiconductor chip.

(Embodiment 6)
Next, a sixth embodiment of the present invention will be described. FIG. 15 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the sixth embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same component as the component mentioned above in FIG.

  A power semiconductor device 1 e shown in FIG. 15 includes an inner resin frame 12 d in place of the inner resin frame 12 with respect to the configuration of the power semiconductor device 1 described above. A metal plate 18 is provided inside the inner resin frame 12d. The metal plate 18 is made of a metal such as iron, copper, or aluminum, or an alloy thereof. Aluminum or an aluminum-based alloy is suitable for reducing the weight, and iron or an iron-based alloy is suitable for requiring explosion-proof properties. The thickness can be arbitrarily selected depending on the required explosion-proof strength. Further, as a method of manufacturing the inner resin frame 12d including the metal plate 18, first, the metal plates 18 are multiply arranged in the mold, and then integrally molded with a molding resin to obtain the inner resin frame 12d.

  According to the sixth embodiment described above, since the free wheel diode chip 4 and the switching chip 5 are separated by the inner resin frame 12d including the metal plate 18, each power semiconductor chip (free wheel diode chip 4 and Even when the switching chip 5) is short-circuit broken, the breaking strength is improved by incorporating the metal plate 18, and the explosion resistance of the inner resin frame 12d is further improved, so that other semiconductor chips that are not short-circuit broken are damaged. Damage can be prevented.

(Embodiment 7)
Next, a seventh embodiment of the present invention will be described. FIG. 16 is a partial cross-sectional view showing the configuration of the power semiconductor device according to the seventh embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the same component as the component mentioned above in FIG.

  A power semiconductor device 1 f shown in FIG. 16 includes metal balls 19 in place of some of the signal terminals 9 among the plurality of signal terminals 9 with respect to the configuration of the power semiconductor device 1 described above. Specifically, in the seventh embodiment, the signal terminal 9 functions as a signal wire for gate in the switching chip 5 connected to the gate / emitter signal substrate 11, and the conductive cover plate 3 and the gate / emitter are connected. A conductive metal ball 19 is interposed between the emitter signal substrate 11. By pulling the emitter signal from the conductive cover plate 3 through the metal ball 19, there is an advantage that the signal wiring length of the emitter signal is shortened, wiring noise is reduced, and connection reliability is excellent.

  The gate / emitter signal substrate 11 is preferably a printed circuit board having two or more layers, or a laminated substrate with an insulating layer interposed therebetween. By using the gate / emitter signal substrate 11 having two or more layers, a gate / emitter signal substrate 11 having a short width is used. The size of the emitter signal substrate 11 can be reduced, and the power semiconductor device can be miniaturized. By using a printed circuit board having two or more layers as the gate / emitter signal substrate 11 or a metal laminate substrate with an insulating layer interposed therebetween, the gate / emitter signal substrate 11 having a short width can be drawn, and the power semiconductor The size of the device can be reduced, and at the same time, it contributes to noise reduction of the gate circuit and the emitter circuit.

  According to the seventh embodiment described above, a metal ball 19 is provided in place of some of the signal terminals 9 among the plurality of signal terminals 9, and the conductive cover plate 3 is interposed via the metal ball 19. Since the emitter signal is drawn, the signal line length of the emitter signal is shortened, wiring noise is reduced, and at the same time, the connection reliability is excellent.

  Moreover, Embodiment 1-7 mentioned above is only an example for implementing this invention, and this invention is not limited to these. Further, the present invention can form various inventions by appropriately combining a plurality of constituent elements disclosed in the respective embodiments and modifications. It is obvious from the above description that the present invention can be variously modified according to specifications and the like, and that various other embodiments are possible within the scope of the present invention.

  As described above, the power semiconductor device according to the present invention is useful for downsizing while pressing with a uniform surface pressure.

1, 1a, 1b, 1c, 1d, 1e, 1f Power semiconductor device 2 Conductive base plate 3 Conductive cover plate 4 Freewheel diode chip 4a, 5a Main electrode 5 Switching chip 5b, 5c Gate / emitter electrode 6 Metal under chip Plate (second chip metal member)
7,7a On-chip metal plate (first chip metal member)
8, 8a, 8b Spring member 9 Signal terminal 10, 10a Support member 11 Gate / emitter signal substrate 11a, 11b Electrode pad 12, 12a, 12b, 12c, 12d Inner resin frame 13 Outer resin frame 14 Sealing resin 15 Yarn 16 Shock absorber rubber sheet 17 Cross 18 Metal plate 19 Metal ball 71 Holding hole 101, 102 Holding hole 103 Concave 104 Boss

Claims (19)

A plurality of power semiconductor chips including switching chips;
A first chip metal member provided on one of the power semiconductor chips;
A second chip metal member provided on the other side of the power semiconductor chip;
A conductive cover plate provided on the first chip metal member side with respect to the power semiconductor chip;
A plurality of spring members for electrically connecting the first chip metal member and the conductive cover plate and pressing the first chip metal member and the conductive cover plate in a direction away from each other;
A gate / emitter signal substrate disposed under the conductive cover plate and electrically connected to the conductive cover plate;
A signal terminal for electrically connecting the signal pad of the switching chip and the gate / emitter signal substrate;
A plurality of holding portions each forming a hollow space for holding the spring member, arranged in parallel in a region formed by an outer periphery of the power semiconductor chip, and with respect to a main surface of the first chip metal member; Supporting means having a plurality of holding portions formed in a vertical direction,
A power semiconductor device comprising: The spring member is
A pressing spring that presses the first chip metal member and the conductive cover plate away from each other;
A conductive spring for electrically connecting the first chip metal member and the conductive cover plate;
The power semiconductor device according to claim 1, comprising: The power semiconductor device according to claim 1, wherein the spring member has a conductive metal plating on a surface thereof. 2. The power semiconductor device according to claim 1, wherein each of the plurality of spring members is any one selected from a square coil spring, a round coil spring, and a leaf spring. The support means has an insulating property and is composed of a prismatic support member provided on the first chip metal member,
The support member is provided on a side in contact with the first chip metal member, and has a recess that forms a hollow space having the same shape as the outer edge of the first chip metal member. The power semiconductor device according to claim 1. The support means is
A prismatic support member having insulation and provided on the first chip metal plate;
A plurality of bosses each extending from an end of the support member and capable of holding the first chip metal member;
The power semiconductor device according to claim 1, comprising: The support means is
A conductive first support member for supporting the spring member;
An insulating second support member for supporting the signal terminal;
The power semiconductor device according to claim 1, comprising: The support means is
A conductive first support member for supporting the spring member;
An insulating second support member for supporting the signal terminal;
Have
The power semiconductor device according to claim 1, wherein the first support member is formed integrally with the first chip metal member. The power semiconductor device according to claim 1, wherein the gate / emitter signal substrate is electrically connected to signal pads of all the switching chips via the signal terminals. A plurality of signal terminals;
The plurality of signal terminals are:
A signal terminal for a gate in the switching chip;
A signal terminal for an emitter in the switching chip;
The power semiconductor device according to claim 1, comprising: A metal ball that is provided between the conductive cover plate and the gate / emitter signal substrate and transmits an emitter signal between the conductive cover plate and the gate / emitter signal substrate;
The power semiconductor device according to claim 1, wherein the signal terminal transmits a gate signal in the switching chip. 2. The power semiconductor device according to claim 1, wherein the gate / emitter signal substrate includes a printed circuit board having two or more layers, or a laminate substrate with an insulating layer interposed therebetween. A conductive base plate provided on the second chip metal member side with respect to the plurality of power semiconductor chips;
One or more inner resin frames that are fixed to the conductive base plate and separate the plurality of power semiconductor chips;
A sealing resin filled in a part of a hollow space formed by the conductive base plate and the inner resin frame;
The power semiconductor device according to claim 1, further comprising: The power semiconductor device according to claim 13, wherein the inner resin frame is made of a high-strength resin having therein a yarn made of continuous high-strength fibers. The power semiconductor device according to claim 13, wherein the inner resin frame is made of high-strength resin having a shock absorbing material rubber sheet therein. The power semiconductor device according to claim 13, wherein the inner resin frame is made of high-strength resin having a cloth made of high-strength fibers impregnated with resin inside. The power semiconductor device according to claim 13, wherein the inner resin frame is made of a high-strength resin having a metal plate therein. The power semiconductor device according to claim 13, wherein a gap is provided between the conductive cover plate and the inner resin frame in a natural state. The power semiconductor device according to claim 1, further comprising an outer resin frame provided around the conductive cover plate.

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