JP2016219778A - Power semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power semiconductor device capable of suppressing a mechanical stress caused by an external substrate at the time when a press-fit terminal is inserted into a hole and the like of an external substrate.SOLUTION: A power semiconductor device comprises: an external form case 11; at least one press-fit terminal 31 buried in an upper surface of the external form case 11; and a plurality of supporting parts (51) formed so as to be protruded from the upper surface of the external form case 11. An upper end of the press-fit terminal 31 is protruded higher from the upper surface of the external form case 11 than an upper surface of the supporting parts (51).SELECTED DRAWING: Figure 2

Description

  The present technology relates to a power semiconductor device having a press-fit terminal.

  Among semiconductor devices, power semiconductor devices are used to control main power of a wide range of equipment, and high reliability is particularly required for transportation equipment.

  As a power semiconductor device as described above, there is a power semiconductor device having a press-fit terminal (see, for example, Patent Document 1).

  On the other hand, there is a technique for dividing the tip of a press-fit terminal to be inserted (see, for example, Patent Document 2). With such a structure, when the press-fit terminal is inserted into the hole of the external substrate, the divided tip is inserted at the start of insertion, and the pair of arms divided at the tip is connected in the latter half of the insertion work. Part is inserted.

JP 2013-152966 A German utility model application 20218295 specification

  The press-fit terminal is provided on the upper surface of the outer case of the power semiconductor device. In the case of Patent Document 1, the upper surface of the outer case has a planar shape. Therefore, when a warp or the like occurs in the external substrate, unintended mechanical stress may occur in the power semiconductor device when the press-fit terminal is inserted into a hole or the like of the external substrate.

  The present technology is for solving the above-described problem, and relates to a power semiconductor device capable of suppressing mechanical stress caused by an external substrate when a press-fit terminal is inserted into a hole or the like of the external substrate. Is.

  A power semiconductor device according to an aspect of the present technology includes an outer case, at least one press-fit terminal embedded in the upper surface of the outer case, and a plurality of support portions formed to protrude from the upper surface of the outer case. The upper end of the press-fit terminal protrudes from the upper surface of the outer case rather than the upper surface of the support portion.

  A power semiconductor device according to an aspect of the present technology includes an outer case, at least one press-fit terminal embedded in the upper surface of the outer case, and a plurality of support portions formed to protrude from the upper surface of the outer case. The upper end of the press-fit terminal protrudes from the upper surface of the outer case rather than the upper surface of the support portion.

  According to such a configuration, only the support portion is in contact with the external substrate on the upper surface of the outer case. Therefore, it is possible to suppress mechanical stress on the power semiconductor device by the external substrate when the press-fit terminal is inserted into the hole of the external substrate.

  The objectives, features, aspects and advantages of the present technology will become more apparent from the detailed description and the accompanying drawings provided below.

It is a top view which illustrates the structure of the power semiconductor device regarding an embodiment. It is sectional drawing which illustrates the structure of the power semiconductor device regarding embodiment. It is sectional drawing which illustrates the internal structure of the power semiconductor device regarding embodiment. It is an enlarged view which shows roughly the cross-sectional shape of an external substrate. It is a top view which illustrates the structure of the power semiconductor device after an external board | substrate was attached. It is a side view which illustrates the structure of the power semiconductor device after an external board | substrate was attached. It is a front view which illustrates the structure of the power semiconductor device after an external board | substrate was attached. It is a figure which illustrates the structure of the press fit terminal of the state provided in the external case. It is a figure which illustrates the structure in which the several press fit terminal was integrated. It is a figure which illustrates structures, such as a press fit terminal, in the upper surface of an outline case. It is a figure which illustrates the waveform of resistance force during inserting a press fit terminal. It is a front view which illustrates the internal structure of the power semiconductor device regarding a modification. It is a front view which illustrates the structure of a press fit terminal when there is no inflection point. It is a side view which illustrates the structure of a press fit terminal when there is no inflection point. It is a side view which illustrates the structure of a press fit terminal when a constriction part is provided.

  Embodiments will be described below with reference to the accompanying drawings. Note that the drawings are schematically shown, and the mutual relationship between the size and position of images shown in different drawings is not necessarily described accurately, and can be changed as appropriate. Moreover, in the description shown below, the same code | symbol is attached | subjected and shown in the same component, and it is the same also about those names and functions. Therefore, the detailed description about them may be omitted.

  In the explanation given below, terms that mean a specific position and direction such as “top”, “bottom”, “side”, “bottom”, “front” or “back” may be used. However, these terms are used for convenience in order to facilitate understanding of the contents of the embodiment, and are not related to the direction in which they are actually implemented.

<Embodiment>
<Configuration>
Hereinafter, the power semiconductor device according to this embodiment will be described.

  FIG. 1 is a plan view illustrating the structure of the power semiconductor device according to this embodiment. FIG. 2 is a cross-sectional view illustrating the structure of the power semiconductor device according to this embodiment.

  The power semiconductor device is covered with an outer case 11. The outer case 11 is an insert-molded case. The material of the outer case 11 is, for example, polyphenylene sulfide resin (PPS). A mounting hole 12 for mounting the heat sink 101 is formed in the outer case 11. The heat sink 101 is a member for radiating heat generated when the power semiconductor device is used.

  On the upper surface of the outer case 11, a press-fit terminal 31 is provided for ensuring electrical connection with an external circuit or the like. Here, the press-fit terminal refers to a terminal that is held by being inserted into a hole or the like without being soldered. In FIG. 2, screw holes 13 are formed in the vicinity of the four corners of the outer case 11 with integrated tips, for screwing an attached external substrate (not shown here). In the case shown in FIG. 1, a total of four screw holes 13 are formed.

  On the upper surface of the outer case 11, there are provided a terminal protection portion 52 that at least partially surrounds the press-fit terminal 31 in a plan view, and a substrate support portion 51 that protrudes from the upper surface of the outer case 11.

  The terminal protection part 52 is formed so as to protrude from the upper surface of the outer case 11, but the substrate support part 51 is formed so as to protrude further than the terminal protection part 52.

  In the example shown in FIG. 2, the substrate support portions 51 are respectively formed near the four corners of the outer case 11. At least one substrate support portion 51 is formed at each of the four corners.

  FIG. 3 is a cross-sectional view illustrating the internal structure of the power semiconductor device according to this embodiment. Hereinafter, the internal structure of the power semiconductor device will be described with reference to FIG. In addition, in FIG. 3, the structure regarding the press fit terminal 31 is shown simply.

  A circuit board 103 is mounted on the power semiconductor device. In the circuit board 103, a copper pattern 26 having a thickness of about 500 μm is formed on a copper base plate 21 having a thickness of about 2 mm with a resin layer 22 as an insulating layer interposed therebetween.

  Furthermore, an insulated gate bipolar transistor (ie, IGBT) 24, which is a silicon (Si) power semiconductor element, is bonded onto a part of the copper pattern 26 using solder. In addition, a free-wheeling diode (FWD) 25 is joined to a part of the copper pattern 26 using solder.

  A plurality of aluminum wires 27 having a diameter of about 200 μm or more and about 400 μm or less are wire-bonded on the IGBT 24 and the FWD 25. The IGBT 24 is connected to the copper pattern 26 or a wire bonding portion (not shown here) of the press-fit terminal 31 through the aluminum wire 27. Similarly, the FWD 25 is connected to the copper bonding pattern 26 or the wire bonding portion of the press-fit terminal 31 through the aluminum wire 27. The copper pattern 26 is further connected to the terminal 100.

  The outer case 11 is filled with an epoxy resin.

  FIG. 4 is an enlarged view schematically showing a cross-sectional shape of the external substrate. The external substrate 41 has a thickness of about 1.6 mm (measured value is about 1.2 mm or more and about 2.0 mm or less).

  For the base material 42 of the external substrate 41, frame re- ertant type-4 (FR-4) is used. In addition, the external substrate 41 is a substrate having four layers including the substrate and the circuit pattern 43 by forming the circuit pattern 43 on the front and back and inside of the substrate. In FIG. 4, the circuit pattern 43 formed inside the substrate is not shown.

  The thickness of the circuit pattern 43 is about 35 μm. However, the circuit pattern 43 formed on the front and back surfaces of the substrate has a thickness of about 60 μm or more and about 85 μm or less because the thickness of the plating is added when a later-described through hole is plated with copper.

  A through hole 44 is formed in the external substrate 41. The press fit terminal 31 is inserted into the through hole 44. A copper plating 45 is formed on the inner wall of the surface-treated through hole 44. The thickness of the copper plating 45 is about 25 μm or more and about 50 μm or less. On the copper plating 45, electroless Sn plating for preventing oxidation of copper is formed. The thickness of the electroless Sn plating is about 1 μm. The diameter of the through hole is about 2.2 mm.

  In addition, a component (not shown here) for driving the power semiconductor device is mounted on the external substrate 41 before the power semiconductor device is attached. Therefore, the external substrate 41 is warped by about 200 μm as an initial warp of the external substrate 41 or as a warp caused by the stress generated after a component for driving the power semiconductor device is soldered to the external substrate 41. Will occur.

  FIG. 5 is a plan view illustrating the structure of the power semiconductor device after the external substrate is attached. FIG. 6 is a side view illustrating the structure of the power semiconductor device after the external substrate is attached. FIG. 7 is a front view illustrating the structure of the power semiconductor device after the external substrate is attached. The attachment of the external substrate to the power semiconductor device will be described with reference to FIGS. In FIG. 7, a groove 53 that is the upper surface of the outer case 11 and a width 53 a of the groove are shown.

  The press-fit terminal 31 of the power semiconductor device is inserted into the through hole 44 of the external substrate 41. Then, the copper plating or the outermost Sn plating formed on the inner wall of the through hole 44 and the press-fit terminal 31 come into contact with each other, so that electrical connection between the two is ensured.

  Here, the press-fit terminal 31 will be described in detail with reference to FIG. FIG. 8 is a diagram illustrating the structure of a press-fit terminal provided in the outer case.

  The press fit terminal 31 includes a front end press fit portion 32, a body portion 33, an embedded portion 34 embedded in the outer case 11, and a wire bond portion 35. The press fit portion 32 is a portion that electrically connects the through hole 44 and the press fit terminal 31 by being inserted into the through hole 44 of the external substrate 41.

  Ni surface Sn plating generally used as an electrical contact is applied to the surface of the press-fit portion 32 and the surface of the body portion 33. The wire bond portion 35 is subjected to Ni plating so that wire bonding with aluminum is possible.

  The plate thickness of the press fit portion 32 is about 0.8 mm, and the maximum width from the center of the press fit portion 32 is about 1.15 mm. After the press-fit terminal 31 is inserted into the through-hole 44 of the external substrate 41, the width of the press-fit portion 32 is that of the through-hole 44 so that the press-fit terminal 31 and the external substrate 41 are appropriately fixed by friction or the like. Slightly larger than the diameter.

  The press-fit portion 32 has a shape (also referred to as a needle eye shape) having an opening 36 inside and bulging outward in order to ensure contact with the inner wall of the through hole 44. In addition, the cross-sectional shape of the press-fit portion 32 in a plane perpendicular to the insertion direction of the press-fit terminal 31 is such that the four corners of the outer peripheral portion are circular so that the contact area increases following the cylindrical shape of the inner wall of the through hole 44. It is arcuate.

  When a current value to be energized is large, a press-fit terminal 31a in which a plurality of press-fit terminals are integrated can be used. FIG. 9 is a diagram illustrating a structure in which a plurality of press-fit terminals are integrated. The integrated press-fit terminals may be referred to as “pins”.

  In the case shown in FIG. 9, the allowable current value per pin is about 67A. Therefore, when the 3 pins are integrated, a current of about 200 A can be applied. By integrating a plurality of pins, the cross-sectional area of the body portion 33 in each pin increases, so that the amount of heat generated during energization can be suppressed. Therefore, the temperature rise in the integrated press-fit terminal 31a can be suppressed. In the case of a signal transmission pin or the like, only energization of about several A per pin is assumed, and it is not necessary to integrate a plurality of pins.

  FIG. 10 is a diagram illustrating the structure of the press-fit terminals 31 and the like on the upper surface of the outer case 11. As illustrated in FIG. 10, the terminal protection part 52 includes an upper surface 52a of the terminal protection part and a side wall 52b of the terminal protection part.

  The cross-sectional area of the press-fit portion 32 in a plane perpendicular to the insertion direction of the press-fit terminal 31 is larger on the base side than the distal end side of the press-fit terminal 31. Alternatively, the cross-sectional area of the press-fit portion 32 in a plane perpendicular to the insertion direction of the press-fit terminal 31 increases from the base side to the tip side of the press-fit terminal 31 and passes a certain point (inflection point). It decreases toward the tip side.

  Further, when there is an inflection point at which the increase / decrease in the cross-sectional area changes, the inflection point is from the upper surface of the substrate support portion 51 on the upper surface of the outer case 11 while the press-fit terminal 31 is embedded in the outer case 11. Also located on the top. Further, after the external substrate 41 is attached to the power semiconductor device, the inflection point is located in the through hole 44.

  Furthermore, the end on the root side of the opening 36, that is, the inner wall on the most base side of the opening 36 is located below the upper surface 52 a of the terminal protection portion on the upper surface of the outer case 11. This is to ensure the spring property of the press-fit terminal 31. By doing in this way, the allowance of the press fit terminal 31 from the upper surface of the external case 11 can be made small. Therefore, the external shape of the power semiconductor device with the external substrate 41 attached can be reduced.

  The press-fit terminal 31 is surrounded by a terminal protection part 52 having an upper surface 52a of the terminal protection part and a side wall 52b of the terminal protection part. Therefore, the creeping distance between the terminals can be increased by the side wall 52b of the terminal protection portion. Therefore, the terminal distance between different electrodes can be reduced. That is, the product can be made smaller.

  The upper surface 52a of the terminal protection part is located between the plurality of substrate support parts 51 in a plan view. The groove 53 which is the upper surface of the outer case 11 is located between the upper surfaces 52a of the plurality of terminal protection portions in plan view.

  Based on the height of the substrate support portion 51, the upper surface 52a of the terminal protection portion is about 1 mm lower. Further, when the height of the substrate support portion 51 is used as a reference, the groove portion 53 that is the upper surface of the outer case 11 is about 4 mm lower. The width 53a of the groove is about 2.73 mm.

  FIG. 13 is a front view illustrating the structure of the press-fit terminal 31 when there is no inflection point. As illustrated in FIG. 13, the length of the press-fit portion 32 in the width direction (the length in the left-right direction in FIG. 13) decreases toward the distal end side of the press-fit terminal 31. By adopting such a structure, it is possible to realize a structure in which the cross-sectional area of the press-fit portion 32 in the plane perpendicular to the insertion direction of the press-fit terminal 31 is larger on the root side than the distal end side of the press-fit terminal 31. .

  FIG. 14 is a side view illustrating the structure of the press-fit terminal 31 when there is no inflection point. As illustrated in FIG. 14, the length in the thickness direction of the press fit portion 32 (the length in the left-right direction in FIG. 14) decreases toward the distal end side of the press fit terminal 31. By adopting such a structure, it is possible to realize a structure in which the cross-sectional area of the press-fit portion 32 in the plane perpendicular to the insertion direction of the press-fit terminal 31 is larger on the root side than the distal end side of the press-fit terminal 31. .

<Action>
The reason for this structure will be described below.

  The size of the outer shape of the power semiconductor device is generally about several tens mm to several hundreds mm. Since the size of the outer shape of the power semiconductor device is relatively large, the influence of manufacturing errors of members used for assembly is large. Therefore, the position where the press-fit terminal is provided also needs to allow a deviation of about 0.25 mm at the maximum with respect to the design dimension. Further, the position of the hole in the external board into which the press-fit terminal is inserted needs to allow a deviation of about 0.1 mm at the maximum. When these deviations are added together, it is necessary to allow for a deviation of about 0.35 mm at the maximum.

  Since the design is such that a relatively large deviation is expected, the tip of the press-fit terminal may not be properly guided into the hole of the external substrate. If the press-fit terminal is not properly guided into the hole of the external substrate, the press-fit terminal may buckle. In that case, the external circuit on the external substrate and the power semiconductor device cannot be electrically connected.

  A press-fit terminal having a needle eye shape is a press-fit terminal having a wide allowable range with respect to such a shift. When using needle-fit press-fit terminals, reduce the thickness or width of the press-fit terminals to reduce the resistance (mainly frictional resistance) when inserting the press-fit terminals into holes on the external board. It is desirable to reduce the cross-sectional area in a plane perpendicular to the insertion direction of the press-fit terminal. However, when a needle-eye shaped press-fit terminal is used for the power semiconductor device, a current of about several tens of A is applied to the press-fit terminal. It is desirable to increase the cross-sectional area in a plane perpendicular to the direction.

  According to this embodiment, even when a manufacturing error of the power semiconductor device or the external substrate occurs, the press-fit terminal 31 is placed in the through hole 44 of the external substrate 41 by using the needle-fit press-fit terminal 31. It is inserted and the press fit part 32 and the through-hole 44 can be made to contact appropriately. Therefore, a highly reliable power semiconductor device can be realized.

  In addition, according to the present embodiment, when the press-fit terminal 31 is inserted into the through hole 44 because the cross-sectional area of the press-fit portion 32 in the plane perpendicular to the insertion direction of the press-fit terminal 31 is small on the tip side. Resistance force (mainly frictional resistance) can be reduced. This is the same whether or not there is an inflection point.

  Moreover, the heat capacity in an electricity supply path becomes large because the cross-sectional area of the base side of the press fit part 32 is large. Therefore, temperature rise due to local heat generation can be suppressed. Therefore, the permissible current per pin can be increased, and the number of pins used in the power semiconductor device can be reduced. Therefore, the power semiconductor device can be reduced. This is the same whether or not there is an inflection point.

  FIG. 11 is a diagram illustrating a waveform of resistance force while the press-fit terminal is inserted. In FIG. 11, the vertical axis indicates the magnitude of the resistance force, and the horizontal axis indicates the magnitude of the displacement. Further, in FIG. 11, a waveform a indicates a case where the cross-sectional area of the press-fit portion is uniform and relatively large along the insertion direction of the press-fit terminal. Moreover, the waveform b shows the case of the press fit part 32 regarding this embodiment. A waveform c indicates a case where the cross-sectional area of the press-fit portion is uniform along the insertion direction of the press-fit terminal and is smaller than the waveform a. Note that there is a correlation between the resistance force at the time of completion of insertion and the removal force.

  As illustrated in FIG. 11, when the cross-sectional area of the press-fit portion is made uniform and the cross-sectional area is increased, the resistance at the start of insertion increases as shown by a waveform a. If the resistance is increased as in the waveform a, the deformation amount of the through hole 44 is increased, and therefore, the possibility of a short circuit between the adjacent through holes 44 is increased.

  Further, if the cross-sectional area of the press-fit portion is made uniform and the cross-sectional area is made small, the resistance force at the start of insertion becomes low as shown by the waveform c. However, in the case of the waveform c, the resistance force at the time of completion of insertion is greatly reduced, and accordingly, the force necessary for removing the press-fit terminal is also reduced. Therefore, it becomes difficult to fix the press-fit terminal in the through hole of the external substrate.

  In the press fit part 32 regarding this embodiment, the cross-sectional area of the front end side of the press fit part 32 is small, and the cross-sectional area of the base side of the press fit part 32 is formed large. When the inflection point is provided, the cross-sectional area in a certain range from the tip of the press fit portion 32 is smaller than the end portion on the root side of the press fit portion 32. By forming in such a manner, an increase in resistance at the start of insertion can be suppressed. In addition, since the rigidity of the base side of the press-fit terminal 31 is high, the force required to remove the press-fit terminal 31 is high after the press-fit terminal 31 is inserted into the through hole 44 of the external substrate 41. Maintained. Therefore, unintentional removal of the press-fit terminal 31 due to the influence of vibration or temperature cycle load is suppressed.

  Further, by increasing the cross-sectional area from the base side to the tip side of the press-fit terminal 31 toward the inflection point, the press-fit in the vicinity of the body part 33 of the press-fit terminal 31 or the body part 33 of the press-fit terminal 31. In the portion 32, a region having a small cross-sectional area is formed. Thereby, even if the position of the hole of the external substrate 41 and the position of the press-fit terminal 31 are slightly shifted, the stress is absorbed in the region having the small cross-sectional area, and the allowable range for the positional shift is widened. Can do.

  Various components for controlling the power semiconductor device are soldered to the external substrate 41. Therefore, the external substrate 41 may be warped by about 200 μm before the power semiconductor device is attached.

  According to the present embodiment, the substrate support portion 51 and the terminal protection portion 52 on the upper surface of the outer case 11 are provided even when the external substrate 41 is warped before being attached to the power semiconductor device. Thus, the warpage of the external substrate 41 can be absorbed.

  That is, since the attached external substrate 41 is in contact with the substrate support portion 51, the external substrate 41 is fixed to the upper surface of the outer case 11 by the substrate support portions 51 provided near the four corners. Then, the warped external substrate 41 is accommodated in a gap in the height direction between the substrate support portion 51 and the upper surface 52a of the terminal protection portion.

  In this way, even when the external substrate 41 is warped before being attached to the power semiconductor device, the warp of the external substrate 41 is increased between the substrate support portion 51 and the upper surface 52a of the terminal protection portion. It can absorb in the gap in the vertical direction. Therefore, it is not necessary to forcibly correct the warp of the external substrate 41 before being attached to the power semiconductor device, so that damage to components on the external substrate 41 or damage to the soldered portion can be suppressed.

  Furthermore, when a temperature cycle load is generated when the power semiconductor device is used, the degree of expansion may be different between the power semiconductor device and the external substrate 41 due to a mismatch in the linear expansion coefficients of the constituent members. However, according to the present embodiment, since the warp of the external substrate 41 can be absorbed as described above, it is possible to suppress the influence caused by the degree of expansion being different.

  Moreover, the following effects are exhibited by providing the outer casing 11 with the groove 53.

  In the power semiconductor device, for example, press-fit terminals 31 of about 35 pins are used. Each press-fit terminal 31 receives a load of about 50 N or more and about 100 N or less per pin, and the through hole 44 of the external substrate 41 is used. Inserted into. Therefore, the entire power semiconductor device is attached to the external substrate 41 under a high load of about 4000 N.

  As described above, the power semiconductor device is constituted by members having various linear expansion coefficients, such as a copper base plate, an IGBT, or a diode chip. For this reason, after the power semiconductor device itself is manufactured, initial warping of about 100 μm at maximum may occur.

  The initial warp of the power semiconductor device is corrected by the high load when the power semiconductor device is attached to the external substrate 41. However, by providing a plurality of groove portions 53, the groove portions 53 can be preferentially deformed with respect to the stress generated in the outer case 11 when the press-fit terminal 31 is inserted.

  In addition, after the power semiconductor device is attached to the external substrate 41, the copper base plate 21 which is the back surface of the power semiconductor device is attached to a heat sink (not shown here). The generated stress can be relaxed. Furthermore, when the temperature cycle load is generated, the stress applied to the outer case 11 can be reduced by the deformation of the groove 53.

  In addition, since the groove portion 53 is provided, the creeping distance for insulation between the plurality of press-fit terminals 31 can be increased, so that the power semiconductor device can be reduced.

  Furthermore, the following effects are demonstrated by providing the terminal protection part 52 in the outer case 11.

  That is, the creeping distance for insulation between the press-fit terminals 31 having different phases can be increased, and the power semiconductor device can be reduced. Further, the rigidity of the power semiconductor device can be increased by the structure of the terminal protection unit 52 itself.

  Further, when the power semiconductor device is attached to the external substrate 41, the warp of the power semiconductor device itself causes not only the vertical direction (for example, the vertical direction in FIG. 3) but also the horizontal direction (for example, the direction perpendicular to the paper surface in FIG. 3). ) Also occurs, but the rigidity of the longitudinal stress can be secured by the copper base plate 21 on the bottom surface of the outer case 11. With respect to the lateral stress, the terminal protector 52 can ensure rigidity.

  By doing in this way, since the number of the press fit terminals 31 which can be used in the semiconductor device for electric power can be increased, an energization current can be increased.

  Further, even when the press-fit terminal 31 enters the through hole 44 whose position is shifted, the press-fit terminal 31 can retain a space for ensuring the spring property. At the same time, deformation of the press-fit terminal 31 due to physical contact from the outside or damage to the press-fit terminal 31 can be prevented.

  In the present embodiment, a power semiconductor device whose inside is sealed with an epoxy resin is shown. However, the present invention can be similarly applied to a power semiconductor device in which the inside is gel-sealed and the upper portion is formed of a lid made of resin or the like, or a power semiconductor device in which the whole is transfer molded.

  Further, the power semiconductor device according to the present embodiment has been exemplified as a structure in which the terminal 100 protrudes from the upper surface of the power semiconductor device. However, as illustrated in FIG. 12, the terminal 100 a is formed from the side surface of the power semiconductor device. Even a protruding structure can be similarly applied. FIG. 12 is a front view illustrating the internal structure of the power semiconductor device according to the modification.

  The power semiconductor device according to this embodiment is exemplified as a structure in which the resin layer 22 as an insulating layer is formed on the copper base plate 21 and the copper pattern 26 is further formed thereon. However, the present invention can be similarly applied to a case where a material such as ceramic is applied as the insulating layer, or a structure in which a copper base plate is soldered under the ceramic in order to improve heat dissipation.

<Effect>
Below, the effect by said embodiment is illustrated.

  According to the above embodiment, the power semiconductor device includes the outer case 11, at least one press-fit terminal 31, and the substrate support portion 51 as a plurality of support portions.

  The press-fit terminal 31 is embedded in the upper surface of the outer case 11. The substrate support 51 is formed so as to protrude from the upper surface of the outer case 11.

  Further, the upper end of the press-fit terminal 31 protrudes from the upper surface of the outer case 11 rather than the upper surface of the substrate support portion 51.

  According to such a configuration, the attached external substrate 41 comes into contact with the substrate support portion 51, so that the external substrate 41 is fixed to the upper surface of the outer case 11 by the substrate support portions 51 provided near the four corners. It will be. Then, even the external substrate 41 having a warped shape fits in the gap in the height direction between the substrate support portion 51 and the upper surface 52a of the terminal protection portion. Therefore, the mechanical stress to the power semiconductor device by the external substrate 41 when the press-fit terminal 31 is inserted into the hole or the like of the external substrate 41 can be suppressed.

  Note that configurations other than these configurations can be omitted as appropriate, but the above-described effects can be produced even when at least one of the other configurations shown in this specification is added as appropriate.

  In addition, according to the above-described embodiment, the power semiconductor device includes the plurality of press-fit terminals 31 and includes the plurality of terminal protection portions 52 as the protection portions formed to protrude from the upper surface of the outer case 11.

  The terminal protector 52 is formed so as to at least partially surround the press-fit terminal 31 in plan view. Moreover, the upper surface of the board | substrate support part 51 protrudes from the upper surface of the outer case 11 rather than the upper surface 52a of a terminal protection part.

  According to such a configuration, the creeping distance for insulation between the press-fit terminals can be efficiently ensured. Moreover, since it is not necessary to enlarge the outer case of the power semiconductor device in order to ensure the creepage distance, the power semiconductor device can be made smaller.

  According to the above embodiment, the press-fit terminal 31 has the opening 36 that penetrates in the direction perpendicular to the insertion direction of the press-fit terminal 31.

  Then, the upper surface 52 a of the terminal protection part is positioned so as to protrude from the upper surface of the outer case 11 with respect to the lower end of the opening 36.

  According to such a structure, since the lower end of the opening part 36 does not protrude from the upper surface 52a of the terminal protection part, the terminal allowance of the press-fit terminal 31 from the external substrate 41 can be suppressed. In addition, the power semiconductor device can be reduced.

  Further, according to the above embodiment, at least one screw hole 13 is formed on the upper surface of the substrate support portion 51.

  According to such a configuration, since the external substrate 41 and the power semiconductor device can be screwed together, the reliability in fixing both is improved.

  Further, according to the above embodiment, the cross-sectional area in a plane perpendicular to the insertion direction of the press-fit terminal 31 is larger on the root side than on the tip side of the press-fit terminal 31.

  According to such a configuration, when the press-fit terminal 31 is inserted into the through hole 44 of the external substrate 41, the resistance force (mainly frictional resistance) can be reduced at the start of insertion. In addition, after the press-fit terminal 31 is inserted into the through hole 44 of the external substrate 41, the force required to remove the press-fit terminal 31 is maintained high. Therefore, unintentional removal of the press-fit terminal 31 due to the influence of vibration or temperature cycle load is suppressed.

  Moreover, since the cross-sectional area of the base side of the press-fit terminal 31 is large, the temperature rise at the time of supplying a large current can be suppressed.

  Further, according to the above-described embodiment, when the cross-sectional area in a plane perpendicular to the insertion direction of the press-fit terminal 31 increases from the root side to the tip side of the press-fit terminal 31 and passes the inflection point. It decreases from the base side of the press-fit terminal 31 toward the tip side.

  The inflection point is positioned so as to protrude from the upper surface of the outer case 11 rather than the upper surface of the substrate support portion 51.

  According to such a configuration, when the press-fit terminal 31 is inserted into the through hole 44 of the external substrate 41, the resistance force (mainly frictional resistance) can be reduced at the start of insertion. In addition, after the press-fit terminal 31 is inserted into the through hole 44 of the external substrate 41, the force required to remove the press-fit terminal 31 is maintained high. Therefore, unintentional removal of the press-fit terminal 31 due to the influence of vibration or temperature cycle load is suppressed.

  Moreover, since the cross-sectional area of the base side of the press-fit terminal 31 is large, the temperature rise at the time of supplying a large current can be suppressed.

<Modification>
In the above-described embodiment, the material, material, dimension, shape, relative arrangement relationship, or implementation condition of each component may be described. However, these are examples in all aspects, and are described in this specification. It is not limited to what has been described. Therefore, innumerable modifications not illustrated are assumed within the scope of the present technology. For example, a case where at least one component is deformed, a case where it is added, or a case where it is omitted are included.

  The position of the terminal in the power semiconductor device, the position of the hole in the substrate, or the like may be shifted due to an individual difference of each component or a manufacturing error in the assembly process. Possible causes of manufacturing errors in the assembly process include, for example, shrinkage after filling with an epoxy resin, or warping of a substrate after soldering.

  When the press-fit terminal is inserted into a hole or the like in a state where the degree of deviation is large, the press-fit portion 32 may be plastically deformed and contact resistance may be increased.

  In such a case, for example, as illustrated in FIG. 15, the constricted portion 104 can be provided on the body portion 33b of the press-fit terminal 31b. FIG. 15 is a side view illustrating the structure of the press-fit terminal when the constricted portion 104 is provided.

  Here, the constricted portion 104 is a portion in which a concave portion is continuously formed in the circumferential direction in the body portion 33b of the press-fit terminal 31b. Therefore, the narrow part 104 has a smaller width in the direction perpendicular to the insertion direction of the press-fit terminal 31b than the other part in the body part 33b.

  With such a structure, the constricted portion 104 is preferentially deformed, so that plastic deformation of the press fit portion 32 can be suppressed. Therefore, an increase in contact resistance when the press-fit terminal 31b is inserted into the through hole 44 of the external substrate 41 can be suppressed. Moreover, the reliability of the press fit terminal 31b can be improved.

  Note that the shape of the cross section of the constricted portion 104 perpendicular to the insertion direction of the press-fit terminal 31b is preferably an arc shape or an elliptical shape.

  In this case, the diameter (X in FIG. 15) of the constricted portion 104 in the cross section perpendicular to the insertion direction of the press-fit terminal 31b is determined from the viewpoint of buckling of the constricted portion 104 and temperature rise due to heat generation during energization. The thickness of the fit terminal 31b, that is, for example, 0.8 mm or more can be set.

  If the diameter (X in FIG. 15) of the constricted portion 104 in the cross section perpendicular to the insertion direction of the press-fit terminal 31b is too large, it is difficult to obtain the above-described effect. Therefore, for example, it can be set to 1.4 mm or less.

  Further, the width (Y in FIG. 15) in the insertion direction of the press-fit terminal 31b of the recess formed continuously in the circumferential direction in the constricted portion 104 is, for example, 1 mm or less in order to preferentially deform the constricted portion 104. It can be.

  In addition, as long as no contradiction arises, “one or more” components described as being provided with “one” in the above-described embodiment may be provided. Furthermore, each component is a conceptual unit, and one component consists of a plurality of structures, one component corresponds to a part of the structure, and a plurality of components. And the case where the component is provided in one structure. Each component includes a structure having another structure or shape as long as the same function is exhibited.

  Also, the descriptions in this specification are referred to for all purposes related to the present technology, and none of them is admitted to be prior art.

  Further, in the above embodiment, when a material name or the like is described without being particularly specified, the material includes other additives, for example, an alloy or the like unless a contradiction arises. .

  DESCRIPTION OF SYMBOLS 11 Outer case, 12 Mounting hole, 13 Screw hole, 21 Copper base board, 22 Resin layer, 24 IGBT, 25 FWD, 26 Copper pattern, 27 Aluminum wire, 31, 31a, 31b Press fit terminal, 32 Press fit part, 33 33b Body part, 34 embedded part, 35 wire bond part, 36 opening part, 41 external substrate, 42 base material, 43 circuit pattern, 44 through hole, 51 substrate support part, 52 terminal protection part, 52a top surface of terminal protection part , 52b Terminal protection part side wall, 53 groove part, 53a groove part width, 100, 100a terminal, 101 heat sink, 103 circuit board, 104 constricted part, a, b, c waveform.

Claims (8)

An outer case,
At least one press-fit terminal embedded in the upper surface of the outer case;
A plurality of support portions formed to protrude from the upper surface of the outer case,
The upper end of the press-fit terminal protrudes from the upper surface of the outer case than the upper surface of the support part.
Power semiconductor device. A plurality of the press-fit terminals are provided,
And further comprising a plurality of protection portions formed to protrude from the upper surface of the outer case,
Each of the protection portions is formed so as to surround each of the press-fit terminals at least partially in plan view,
The upper surface of the support part protrudes from the upper surface of the outer case than the upper surface of each protection part,
The power semiconductor device according to claim 1. Each press-fit terminal has an opening that penetrates in a direction perpendicular to the insertion direction of each press-fit terminal,
The upper surface of each of the protection portions is positioned so as to protrude from the upper surface of the outer case than the lower end of each opening.
The power semiconductor device according to claim 2. At least one screw hole is formed on the upper surface of the support portion.
The power semiconductor device according to any one of claims 1 to 3. The cross-sectional area in a plane perpendicular to the insertion direction of the press-fit terminal is larger on the root side than the tip side of the press-fit terminal,
The power semiconductor device according to any one of claims 1 to 4. The cross-sectional area in a plane perpendicular to the insertion direction of the press-fit terminal increases from the base side of the press-fit terminal toward the tip side, and when the inflection point is passed, the base side to the tip side of the press-fit terminal Decrease towards
The inflection point is located so as to protrude from the upper surface of the outer case than the upper surface of the support portion.
The power semiconductor device according to any one of claims 1 to 4. The press-fit terminal further comprises a constricted portion provided on the base side from the opening,
The constricted portion has a width in a direction perpendicular to the insertion direction of the press-fit terminal smaller than other portions of the press-fit terminal,
The power semiconductor device according to claim 3. The shape of the cross section of the constricted portion perpendicular to the insertion direction of the press-fit terminal is an arc shape or an elliptical shape,
The power semiconductor device according to claim 7.

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