Semiconductor power module with high speed operation and miniaturization

• US 5,747,875 A
• Filed: 07/02/1996
• Issued: 05/05/1998
• Est. Priority Date: 09/08/1993
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Oshima, Seiichi
• Primary Examiner(s): BROWN, PETER T
• Application Number:
  US08/675,337
• Time in Patent Office: 672 Days
• Field of Search: 257/701-703, 257/705, 257/706, 257/712, 257/718, 257/719, 257/724, 257/687, 257/690
• US Class Current: 257/687
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48139 with an intermediate bond, e.g. continuous wire daisy chain
• CPC Class Codes: H01L 2224/49111 the connectors connecting two common bonding areas, e.g. Litz or braid wires
• CPC Class Codes: H01L 25/16 the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00011 Not relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/01004 Beryllium [Be]
• CPC Class Codes: H01L 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01033 Arsenic [As]
• CPC Class Codes: H01L 2924/1305 Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/15153 the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/1517 Multilayer substrate
• CPC Class Codes: H01L 2924/16195 Flat cap [not enclosing an internal cavity]
• CPC Class Codes: H02M 7/003 Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H05K 1/0306 Inorganic insulating substrates, e.g. ceramic, glass
• CPC Class Codes: H05K 1/141 One or more single auxiliary printed circuits mounted on a main printed circuit, e.g. modules, adapters H05K1/142 and H05K1/147 take precedence
• CPC Class Codes: H05K 1/182 : associated with components mounted in the printed circuit board, e.g. insert mounted components [IMC]
• CPC Class Codes: H05K 2201/09072 : Hole or recess under component or special relationship between hole and component
• CPC Class Codes: H05K 2203/049 : Wire bonding
• CPC Class Codes: H05K 3/0061 : onto a metallic substrate, e.g. a heat sink heat sinks for electric apparatus H05K7/20
• CPC Class Codes: H05K 3/328 : by welding
• CPC Class Codes: H05K 3/368 : parallel to each other H05K3/361 takes precedence
• CPC Class Codes: H05K 5/0091 : Housing specially adapted for small components for resistors H01C; for capacitors H01G; for integrated circuits H01L23/00

Abstract

In order to obtain a miniature unit having a simple structure which can operate at a high speed at a low cost, a copper pattern (225) provided on a power substrate (221) having a DBC substrate structure is exposed on an outer surface of the unit. Thus, it is possible to discharge heat which is generated in a main circuit of the unit to the exterior without providing a copper base plate by mounting the unit so that the pattern (225) is directly in contact with an external heat slinger or the like. The power substrate (221) is not deformed following its temperature change, since no copper base plate is required. Thus, no S-bent structure is required for a terminal which is connected with the circuit or the like, whereby speed increase and miniaturization are enabled, while the structure is simplified since no silicone gel is required.

Claims

1. A semiconductor power module comprising a box type housing storing a power switching semiconductor element repeating cutoff and connection of a current to be supplied to a load in response to a control signal,

a bottom portion of said housing comprising a power substrate being integrally provided with:

a power substrate body formed of a single layer and containing a heat-resistant insulating material;

a thermally and electrically conductive power interconnection pattern being bonded to an upper major surface of said power substrate body to be connected with said power switching semiconductor element;

a thermally conductive plate being formed of a single layer and directly bonded to a lower major surface of said power substrate body, said plate being formed of a material substantially identical to that of said power interconnection pattern; and

said plate being exposed on a lower surface of said housing;

wherein said heat-resistant insulating material is ceramic,

wherein said power interconnection pattern substantially consists of a copper material and is arranged on said upper major surface of said power substrate body in metallization bonding, and

wherein said plate substantially consists of a copper material and is arranged on said lower major surface of said power substrate body in metallization bonding;

wherein said bottom portion of said housing comprises a control substrate having;

a control substrate body substantially consisting of an insulator,

an electrically conductive control interconnection pattern being arranged on an upper major surface of said control substrate body and connected with a control circuit element for producing said control signal and supplying the same to said power switching semiconductor element, and

a plate type pressing member forming a multilayer structure with said control substrate body, said plate type pressing member having rigidity,

said control substrate being arranged around said power substrate and engaged with an edge portion of said power substrate.

2. A semiconductor power module in accordance with claim 1, wherein

said housing comprises a bottomless case being bonded to said bottom portion by an adhesive for covering an upper space of said bottom portion.

3. A semiconductor power module comprising a box type housing storing a power switching semiconductor element repeating cutoff and connection of a current to be supplied to a load in response to a control signal,

a bottom portion of said housing comprising a power substrate being integrally provided with:

a power substrate body containing a heat-resistant insulating material;

a thermally and electrically conductive power interconnection pattern being one of bonded to and arranged on an upper major surface of said power substrate body to be connected with said power switching semiconductor element; and

a thermally conductive plate being one of bonded to and arranged on a lower major surface of said power substrate body, said plate being formed of a material substantially identical to that of said power interconnection pattern;

said bottom portion further comprising a control substrate having;

a control substrate body substantially comprising an insulator;

an electrically conductive control interconnection pattern being arranged on an upper major surface of said control substrate body and connected with a control circuit element for producing said control signal and supplying the same to said power switching semiconductor element; and

a plate type pressing member forming a multilayer structure with said control substrate body, said plate type pressing member having rigidity;

said control substrate being arranged around said power substrate and engaged with an edge portion of said power substrate;

wherein said bottom portion of said housing further comprises;

a plate-type spacer having an inner peripheral edge being provided around said power substrate to be in contact with an outer peripheral edge of said power substrate, said plate-type spacer being in contact with a lower major surface of said control substrate.

4. A semiconductor power module in accordance with claim 3, wherein

the ratio of the thickness of said power interconnection pattern to that of said plate is so adjusted that said power substrate is not warped following its temperature change.

5. A semiconductor power module in accordance with claim 3, wherein

said spacer has elasticity,

a lower surface of said spacer being substantially flush with that of said plate.

6. A semiconductor power module in accordance with claim 3, wherein

said spacer has elasticity,

a lower major surface of said spacer projecting downwardly beyond that of said plate.

7. A semiconductor power module in accordance with claim 3, wherein

a lower major surface of said plate projects downwardly beyond that of said spacer.

8. A semiconductor power module in accordance with claim 3, wherein

said power substrate further comprises:

a contact member being arranged on an upper edge of said upper major surface of said power substrate body to be in contact with said control substrate, said contact member substantially consisting of a metal.

9. A semiconductor power module in accordance with claim 3, wherein

said pressing member comprises a metal plate.

10. A semiconductor power module in accordance with claim 3, wherein

said control substrate is provided with an opening passing through a central portion of its major surface, said power substrate being positioned in said opening.

11. A semiconductor power module in accordance with claim 10, wherein

an upper major surface of said power substrate being positioned in said opening is located downward beyond that of said control substrate,

precoating resin being provided in said opening for covering said power switching element.

12. A semiconductor power module in accordance with claim 3, wherein

said inner peripheral edge of said spacer is in contact with said outer peripheral edge of said power substrate through a flexible adhesive.

13. A semiconductor power module in accordance with claim 3, wherein

an upper major surface of said spacer is in contact with said lower major surface of said control substrate,

said spacer and said control substrate being fixed to each other.

14. A semiconductor power module in accordance with claim 13, wherein

said spacer and said control substrate are fixed to each other by an adhesive.

15. A semiconductor power module in accordance with claim 13, wherein

said spacer and said control substrate are fixed to each other through a screw.

16. A semiconductor power module in accordance with claim 3, further comprising:

a thermally conductive plate-type heat-conducting plate being provided to be in contact with a lower portion of said bottom portion of said housing, said heat-conducting plate having an upper major surface being slidable along a lower major surface of said plate.

17. A semiconductor power module in accordance with claim 16, wherein

said heat-conducting plate is fixed to said spacer.

18. A semiconductor power module in accordance with claim 16, wherein

said upper major surface of said heat-conducting plate is mounted on said lower major surface of said plate through a flexible adhesive.