Array of power semiconductors with heat sink

Abstract

An array of power semiconductors with heat sinks, including power semiconductors and heat sinks, is provided. The power semiconductor has a power semiconductor die, a plurality of first terminals, and a second terminal. The power semiconductor die has a plurality of semiconductor terminals. Each of the first terminals is electrically coupled to an associated one of the semiconductor terminals. The second terminal is a surface mount terminal and is electrically coupled to one of the first terminals. The heat sink has a heat sink body and a plurality of fins. The heat sink body has a base and an outer surface. The base is fixedly and directly coupled to the surface mount terminal. The outer surface has a fin mounting portion from which the plurality of fins extend. At least a portion of the fin mounting portion is oriented non-parallel to the base.

Description

Cross - reference to related applications

[0001]

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 354,262, filed on June 22, 2022, the disclosure of which is incorporated herein by reference in its entirety as if fully set forth herein.

Technical Field

[0002]

[0002] The present disclosure relates to a power semiconductor with a heat sink, and related inverters, motor assemblies, and vehicle drive units.

Background Art

[0003]

[0003] This section provides background art information related to the present disclosure, which is not necessarily prior art.

[0004]

[0004] U.S. Patent No. 11,303,183 by the same applicant discloses a motor assembly having an inverter with a plurality of power semiconductors with heat sinks, each power semiconductor with a heat sink comprising a power semiconductor and a heat sink fixedly coupled to the power semiconductor. The power semiconductor can be any type of power semiconductor that can be controlled to selectively transmit power, such as a MOSFET or an IGBT, and has a power semiconductor die, a plurality of pin terminals electrically coupled to the power semiconductor die, and a plate terminal electrically coupled to one of the pin terminals. The heat sink may be formed of a suitable material such as copper and is coupled to the plate terminal by a suitable method such as a solder connection that mechanically joins and electrically couples the heat sink to the plate terminal. A suitable fluid circulates through the inverter and passes through the fins of the heat sink to cool the power semiconductor with the heat sink during operation of the motor assembly.

[0005]

[0005] International Patent Application No. PCT / US2022 / 026127 by the same applicant discloses a motor assembly having an inverter with a plurality of power semiconductors with heat sinks and heat sinks fixedly coupled to the power semiconductors. The power semiconductor can be any type of power semiconductor that can be controlled to selectively transmit power, such as a MOSFET or IGBT, and can have a power semiconductor die, a plurality of pin terminals electrically coupled to the power semiconductor die, and a plate terminal electrically coupled to one of the pin terminals. The heat sink may be formed of a suitable material such as copper and is coupled to the plate terminal by a sintering operation. A suitable fluid circulates through the inverter and passes through the fins of the heat sink to cool the power semiconductor with the heat sink during operation of the motor assembly. The sintered joint between the heat sink and the plate terminal is relatively stronger than the solder joint disclosed in U.S. Patent No. 11303183.

[0006]

[0006] U.S. Patent Application Publication No. 2022 / 0037241 by the same applicant discloses a motor assembly having an inverter with a plurality of power semiconductors with heat sinks in which the heat sink and the plate terminal are integrally and integrally formed. By configuring it in this way, the joint between the heat sink and the plate terminal is eliminated.

[0007]

[0007] The above configurations are satisfactory for their intended purposes, but still, there is still a need in the art for power semiconductors with heat sinks that can dissipate heat from the power semiconductors at a relatively high rate.

SUMMARY OF THE INVENTION

[0008]

[0008] This section provides a general overview of the present disclosure and does not disclose the full scope or all of its features comprehensively.

[0009]

[0009] In one form, the present disclosure provides an array of power semiconductors with heat sinks, including a power semiconductor and a heat sink. The power semiconductor has a power semiconductor die, a plurality of first terminals, and a second terminal. The power semiconductor die has a plurality of semiconductor terminals. Each of the first terminals is electrically coupled to an associated one of the semiconductor terminals. The second terminal is a surface mount terminal and is electrically coupled to one of the first terminals. The heat sink has a heat sink body and a plurality of sets of fins. The heat sink body has a base and a plurality of interface surfaces. The base is fixedly and directly coupled to the surface mount terminal. Each of the interface surfaces terminates in an associated interface plane. Each of the interface planes intersects at least one of the other interface planes. Each of the plurality of sets of fins is fixedly coupled to the body and extends directly from an associated one of the interface surfaces.

[0010]

[0010] In another form, the present disclosure provides an array of power semiconductors with heat sinks, including a power semiconductor and a heat sink. The power semiconductor has a power semiconductor die, a plurality of first terminals, and a second terminal. The power semiconductor die has a plurality of semiconductor terminals. Each of the first terminals is electrically coupled to an associated one of the semiconductor terminals. The second terminal is a surface mount terminal and is electrically coupled to one of the first terminals. The heat sink has a heat sink body and a plurality of fins. The heat sink body has a base and an outer surface. The base is fixedly and directly coupled to the surface mount terminal. The outer surface has a fin mounting portion where the plurality of fins extend. At least a portion of the fin mounting portion is oriented non-parallel to the base.

[0011]

[0011] In yet another form, the present disclosure provides an array of power semiconductors with heat sinks, each of the power semiconductors with heat sinks having a power semiconductor and a heat sink. Each power semiconductor has a power semiconductor die, a plurality of first terminals, and a second terminal. The power semiconductor die has a plurality of semiconductor terminals. Each of the first terminals is electrically coupled to an associated one of the semiconductor terminals. The second terminal is a surface mount terminal and is electrically coupled to one of the first terminals. The heat sink has a heat sink body and a plurality of fins. The heat sink body has a base and an outer surface. The base is fixedly and directly coupled to the surface mount terminal. The outer surface has a fin mounting portion from which the plurality of fins extend. At least a portion of the fin mounting portion is oriented non-parallel to the base. The power semiconductors with heat sinks are arranged such that a portion of the plurality of fins on one power semiconductor with heat sink of the plurality of power semiconductors with heat sinks and a portion of the plurality of fins on an adjacent one power semiconductor with heat sink of the plurality of power semiconductors with heat sinks are disposed in associated flow paths adapted to receive a coolant flow.

[0012]

[0012] Further applicable areas will become apparent from the description provided herein. The description and specific examples in this summary are intended for illustration purposes only and are not intended to limit the scope of the present disclosure.

[0013]

[0013] The drawings described herein are for the purpose of illustrating selected embodiments only and not all possible implementations, and are not intended to limit the scope of the present disclosure.

Brief Description of the Drawings

[0014]

Figure 1

[0014] A perspective view of a power semiconductor with a heat sink constructed in accordance with the teachings of the present disclosure.

Figure 2

[0015] It is a bottom view of the power semiconductor with a heat sink in FIG. 1.

Figure 3

[0016] It is a perspective view of a part of the power semiconductor with a heat sink.

Figure 4

[0017] It is a side view of the power semiconductor with a heat sink in FIG. 1.

Figure 5

[0018] It is a top view of a part of an inverter for a motor assembly, and the inverter incorporates a linear array of the power semiconductors with heat sinks in FIG. 1.

Figure 6

[0019] It is a top view of a part of an inverter for a motor assembly, and each of the inverters incorporates at least one radial array of the power semiconductors with heat sinks in FIG. 1.

Figure 7

Figure 8

[0020] It is a perspective view of the alternately configured heat sink.

Figure 9

Figure 10

Best Mode for Carrying Out the Invention

[0015]

[0021] Corresponding reference numerals indicate corresponding parts throughout several views of the drawings.

[0016]

[0022] Referring to FIGS. 1 - 4 of the drawings, a power semiconductor with a heat sink constructed in accordance with the teachings of the present disclosure is generally indicated by reference numeral 10. The power semiconductor 10 with a heat sink can include a power semiconductor 12 and a heat sink 14.

[0017]

[0023] The power semiconductor 12 can be any type of power semiconductor, such as a transistor. For example, the power semiconductor 12 may be an insulated gate bipolar transistor (IGBT), but in the specific example provided, it is a metal oxide semiconductor field effect transistor (MOSFET). The power semiconductor 12 can include a semiconductor die 20, a plurality of pin terminals 22, a plate terminal 24, and a sealing body 26. The semiconductor die 20 can have a plurality of semiconductor terminals (not specifically shown) each electrically coupled to an associated one of the pin terminals 22. In the example provided, the semiconductor die 20 has four semiconductor terminals including a gate (not specifically shown), a source sense (not specifically shown), a source (not specifically shown), and a drain (not specifically shown). Each of the pin terminals 22 is formed of a conductive metal material such as copper and can be electrically coupled to an associated one of the semiconductor terminals. For example, each of the pin terminals 22 can be joined to an associated one of the semiconductor terminals using a solder material, thereby electrically and physically coupling the pin terminal 22 to an associated one of the semiconductor terminals. Alternatively, one or more bond wires 30 can be used to electrically couple one of the pin terminals 22 to an associated one of the semiconductor terminals. The plate terminal 24 can be electrically coupled to one of the pin terminals 22 and can be directly mounted to one of the semiconductor terminals. In the example provided, the pin terminal 22a is electrically coupled to the gate, the pin terminal 22b is electrically coupled to the source sense, the pin terminal 22c is electrically coupled to the source, and the pin terminal 22d is electrically coupled to both the drain and the plate terminal 24. The plate terminal 24 is formed of a suitable conductive metal material such as copper. The sealing body 26 is formed of a sealing material disposed to cover the semiconductor die 20. The semiconductor die 20 and the bond wires 30 are completely sealed within the sealing material, and the pin terminals 22 are partially sealed within the sealing material. Optionally, the plate terminal 24 can be partially sealed within the sealing material.

[0018]

[0024] The heat sink 14 can have a body or heat sink base 40 and a plurality of fins 42 fixedly coupled to the heat sink base 40 and protruding outwardly from the heat sink base 40. The heat sink base 40 may be formed of a suitable material such as copper, and can be formed in a shape that allows at least two separate sets of fins 42 to protrude from the heat sink base 40 in different directions. In the example provided, the heat sink base 40 is of a generally wedge shape having a bottom or base surface 50, a pair of first surfaces 52, and a pair of second surfaces 54. The first surfaces 52 face each other and intersect along a straight vertex 60. The first surfaces 52 are boundary surfaces of the heat sink base 40 and terminate in respective boundary planes P1, P2. One boundary plane P1 of one of the first surfaces 52 can intersect the second adjacent boundary plane P2 of the first surfaces 52. Optionally, adjacent ones of the first surfaces 52 can intersect each other.

[0019]

[0025] Each set 62 of fins 42 extends perpendicularly from each of the first surfaces 52. The fins 42 of each set 62 of fins 42 may be fixedly coupled to the heat sink base 40 and can extend directly from one of the associated ones of the first surfaces 52. At least one set 62 of fins 42 can be formed integrally and monolithically with the heat sink base 40. The sets 62 of fins 42 on adjacent pairs of the first surfaces 52 can be symmetrically disposed about a symmetry plane P3 that intersects the boundary planes P1, P2 of the adjacent pairs of the first surfaces 52. The second surfaces 54 are, in this particular example, flat, face each other, and are parallel to each other. It will be understood that the heat sink base 40 may be shaped differently and / or the fins 42 may be formed on or protrude from additional or other surfaces or sides of the heat sink base 40 than those shown in the accompanying drawings. For example, the heat sink base 40 may be shaped as a pyramid or frustum of a pyramid, and the sets of fins 42 may be formed on two or more surfaces of the pyramid or frustum of a pyramid.

[0020]

[0026] Each set 62 of fins 42 can be shaped and spaced in any desired manner. In the specific example provided, each of the fins 42 has a tapered rod-like configuration with an elliptical cross-sectional shape that is relatively large where the proximal end of the fin 42 abuts the heat sink base 40 and relatively narrow at the opposite or distal end. Further, the distal end of the fin 42 is inclined so as to be located in a plane that is not perpendicular to the longitudinal axis of the fin 42. Thus, the fins 42 are not of uniform height in the example provided. If desired, the heat sink 14 can be integrally and singularly formed in a desired manner such as investment casting, cold forging, or metal injection molding (MIM). Alternatively, the heat sink base 40 and the fins 42 may be formed as separate components and may be assembled together such that the fins 42 are fixedly coupled to the heat sink base 40.

[0021]

[0027] The heat sink base 40 and the plate terminal 24 may be formed singly and integrally with each other. Alternatively, the heat sink base 40 and the plate terminal 24 may be fixedly and electrically coupled to each other, for example, by soldering or sintering.

[0022]

[0028] FIGS. 5-7 show the heat sink-equipped power semiconductor 10 as integrated into an inverter of a motor assembly used within an electric drive unit for a vehicle. The inverter, the motor assembly, and the electric drive unit may be configured as described in U.S. Patent No. 11,303,183, or International Patent Application No. PCT / US2022 / 019900 filed on March 11, 2022, the disclosures of which are incorporated herein by reference in their entirety and in detail.

[0023]

[0029] Referring to FIG. 5, the power semiconductor 10 with heat sink may be arranged in one or more linear arrays 70, where adjacent ones of the power semiconductors 10 with heat sink are nested together such that sets 62 of fins 42 on adjacent sides of the power semiconductors 10 with heat sink cooperate to form flow paths 74. The linear array 70 may be exposed to a flow of coolant F that is generally perpendicular to the linear array 70. The coolant contacting the linear array 70 may be forced through the flow paths 74 (i.e., between sets 62 of fins 42 on the first surface 52 of adjacent heat sinks 14). In the illustrated example, adjacent power semiconductors 10 with heat sink are shown as being offset from each other such that the flow paths 74 include a space between adjacent power semiconductors 10 with heat sink. However, it will be understood that sets 62 of fins 42 of adjacent power semiconductors 10 with heat sink may be nested together. Thus, it will be understood that each flow path 74 consists of the volume of the space between the first surfaces 52 of adjacent heat sinks 14, with the volume of the fins 42 extending from the first surfaces 52 of the adjacent heat sinks 14 reduced.

[0024]

[0030] Alternatively, the power semiconductor 10 with heat sink may be arranged in one or more radial arrays, as shown in FIGS. 6 and 7. In the example of FIG. 6, the coolant flows in a radially outward direction through the flow paths 74 from within the radial array 80. In the example of FIG. 7, two concentric radial arrays 80a and 80b are used, and the flow paths 74 formed between the power semiconductors 10 with heat sink of the two radial arrays 80a and 80b allow for a flow of coolant in a radial direction (in the radially inward direction in the illustrated example) through the radial arrays 80a and 80b.

[0025]

[0031] It will be understood that an array of power semiconductors 10 with heat sinks may be formed to have a geometry other than that described herein and shown in the accompanying drawings. Further, the coolant flow may be directed to pass through the array of power semiconductors 10 with heat sinks in a direction different from that described herein and shown in the accompanying drawings. For example, the coolant flow may be directed to be orthogonal to the array. In the examples of FIGS. 5-7, the coolant flow may be directed into or out of the page of the drawing rather than in the particular direction illustrated.

[0026]

[0032] Referring to FIG. 8, a first alternately constructed heat sink 14a is shown. In this example, the heat sink base 40a and each of two separate sets of fins 42a are formed as individual components fixedly joined to each other, for example, by sintering, brazing, soldering, and / or welding. Each set of fins 42a can include a plurality of fin subsets 42a-1 formed from a strip of material such as copper and is bent to form a plurality of alternating protrusions 42a-2 of a desired shape. In the example provided, the alternating protrusions 42a-2 of each fin subset 42a-1 are formed to have a rectangular wave shape, and the alternating protrusions 42a-2 of each adjacent pair of fin subsets 42a-1 are offset from each other.

[0027]

[0033] In the example of FIG. 9, a channel 50b-1 is formed in the heat sink base 40b of the heat sink 14b. The channel 50b-1 defines a base surface 50b and is sized to receive the power semiconductor 12 (FIG. 1) therein. Thus, it will be understood that when the heat sink 14b is mounted to the power semiconductor 12 (FIG. 1), the heat sink base 40b covers the side surface of the power semiconductor 12 (FIG. 1).

[0028]

[0034] The example of FIG. 10 illustrates the fin set 42c of the heat sink 14c as being formed from columnar fins having a rhombic and triangular cross-sectional shape. It will be understood that the fins of the fin set may be configured in a variety of different ways, including columnar fins having a circular or square shape.

[0029]

[0035] The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. The individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, may be interchangeable and may be used in the selected embodiment, even if not specifically illustrated or described. The same may be modified in many ways. Such modifications should not be regarded as departing from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims

1. An array of power semiconductors with heat sinks, a power semiconductor having a power semiconductor die, a plurality of first terminals, and a second terminal, wherein the power semiconductor die has a plurality of semiconductor terminals, each of the first terminals is electrically coupled to an associated one of the semiconductor terminals, the second terminal is a surface mount terminal, and is electrically coupled to one of the first terminals, a heat sink having a heat sink body and a plurality of sets of fins, wherein the heat sink body has a base and a plurality of boundary surfaces, the base is fixedly and directly coupled to the surface mount terminal, each of the boundary surfaces terminates in an associated boundary surface plane, each of the boundary surface planes intersects at least one of the other boundary surface planes, and each of the plurality of sets of fins is fixedly coupled to the heat sink body and extends directly from an associated one of the boundary surfaces, comprising an array of power semiconductors with heat sinks.

2. The array of power semiconductors with heat sinks according to claim 1, wherein a first boundary surface of the boundary surfaces intersects at least one of the other boundary surfaces.

3. The array of power semiconductors with heat sinks according to claim 1, wherein the heat sink body has two boundary surfaces.

4. The array of power semiconductors with heat sinks according to claim 1, wherein at least one of the plurality of sets of fins is integrally formed with the heat sink body in a single piece.

5. The array of power semiconductors with heat sinks according to claim 1, wherein the plurality of sets of fins on an adjacent pair of boundary surfaces are symmetrically arranged about a symmetry plane that intersects the boundary surface planes of the adjacent pair of boundary surfaces.

6. An array of power semiconductors with heat sinks, a power semiconductor having a power semiconductor die, a plurality of first terminals, and a second terminal, wherein the power semiconductor die has a plurality of semiconductor terminals, each of the first terminals is electrically coupled to an associated one of the semiconductor terminals, the second terminal is a surface mount terminal, and is electrically coupled to one of the first terminals, A heat sink with a heat sink body and a plurality of fins, wherein the heat sink body has a base and an outer surface, the base is fixedly and directly coupled to the surface mount terminal, the outer surface has a fin mounting portion where the plurality of fins extend, and at least a portion of the fin mounting portion is non-parallel to the base. An array of power semiconductors with heat sinks, comprising. **Claim 7** The array of power semiconductors with heat sinks according to claim 6, wherein the fin mounting portion includes a first planar segment and a second planar segment that are not parallel to each other. **Claim 8** The array of power semiconductors with heat sinks according to claim 7, wherein the first planar segment and the second planar segment intersect each other. **Claim 9** The array of power semiconductors with heat sinks according to claim 6, wherein at least a portion of the plurality of fins is formed integrally and monolithically with the heat sink body. **Claim 10** An array of power semiconductors with heat sinks, comprising a plurality of power semiconductors with heat sinks, each of the power semiconductors with heat sinks having a power semiconductor and a heat sink, the power semiconductor having a power semiconductor die, a plurality of first terminals, and a second terminal, the power semiconductor die having a plurality of semiconductor terminals, each of the first terminals being electrically coupled to an associated one of the semiconductor terminals, the second terminal being a surface mount terminal and being electrically coupled to one of the first terminals, the heat sink having a heat sink body and a plurality of fins, the heat sink body having a base and an outer surface, the base being fixedly and directly coupled to the surface mount terminal, the outer surface having a fin mounting portion where the plurality of fins extend, and at least a portion of the fin mounting portion being non-parallel to the base, The array of power semiconductors with heat sinks, wherein a portion of the plurality of fins of one of the power semiconductors with heat sinks and a portion of the plurality of fins of an adjacent one of the power semiconductors with heat sinks are arranged to be disposed in an associated flow path adapted to receive a coolant flow. **Claim 11** The fin mounting portions of the respective heat sinks include a first planar segment and a second planar segment that are not parallel to each other, the array of power semiconductors with heat sinks according to claim 10.

12. The first planar segment and the second planar segment intersect each other, the array of power semiconductors with heat sinks according to claim 11.

13. The heat sink body and at least a part of the plurality of fins of each heat sink are integrally and integrally formed, the array of power semiconductors with heat sinks according to claim 10.

14. A first portion of the power semiconductor with heat sink is arranged in a first row, a second portion of the power semiconductor with heat sink is arranged in a second row parallel to the first row, and the power semiconductors with heat sinks of the first portion and the second portion are nested with each other, the array of power semiconductors with heat sinks according to claim 10.

15. At least a first portion of the power semiconductor with heat sink is arranged around a central longitudinal axis, and the power semiconductor with heat sink of at least the first portion is circumferentially spaced around the central longitudinal axis, and a flow path is formed along the central longitudinal axis, the array of power semiconductors with heat sinks according to claim 10.

16. A second portion of the power semiconductor with heat sink is arranged around the central longitudinal axis, and the power semiconductor with heat sink of the second portion is circumferentially spaced around the central longitudinal axis, and the power semiconductor of the second portion of the power semiconductor with heat sink is arranged radially outside the power semiconductor of at least the first portion of the power semiconductor with heat sink, the array of power semiconductors with heat sinks according to claim 15.

17. The heat sink of at least the first portion of the power semiconductor with heat sink and the heat sink of the second portion of the power semiconductor with heat sink are nested together such that a portion of the plurality of fins of one power semiconductor with heat sink faces a portion of one of the plurality of adjacent fins of the power semiconductor with heat sink. The array of power semiconductors with heat sink according to claim 16.

18. The heat sink of at least the first portion of the power semiconductor with heat sink is nested together such that a portion of the plurality of fins of one power semiconductor with heat sink faces a portion of one of the plurality of adjacent fins of the power semiconductor with heat sink. The array of power semiconductors with heat sink according to claim 16.

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