Semiconductor power module with ceramic substrate

• US 4,731,644 A
• Filed: 06/16/1986
• Issued: 03/15/1988
• Est. Priority Date: 06/15/1985
• Status: Expired due to Term

• Current Assignee: IXYS Corporation (Littelfuse Incorporated)
• Original Assignee: Brown Boveri & CIE AG (ABB Limited)
• Inventors: Neidig, Arno
• Primary Examiner(s): James, Andrew J.
• Assistant Examiner(s): Clark, S. V.
• Application Number:
  US06/874,572
• Time in Patent Office: 638 Days
• Field of Search: 357/81, 357/72, 357/82, 357/79, 357/80
• US Class Current: 257/687
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/371 with a principal constituent of the material being a metal or a metalloid, e.g. boron [B], silicon [Si], germanium [Ge], arsenic [As], antimony [Sb], tellurium [Te] and polonium [Po], and alloys thereof
• CPC Class Codes: H01L 2224/40095 Kinked
• CPC Class Codes: H01L 2224/40225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/40491 being an additional member attached to the bonding area through an adhesive or solder, e.g. buffer pad
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48095 Kinked
• CPC Class Codes: H01L 2224/48472 the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
• CPC Class Codes: H01L 2224/73221 Strap and wire connectors
• CPC Class Codes: H01L 2224/83801 Soldering or alloying
• CPC Class Codes: H01L 2224/84801 Soldering or alloying
• CPC Class Codes: H01L 23/053 the container being a hollow construction and having an insulating or insulated base as a mounting for the semiconductor body
• CPC Class Codes: H01L 23/16 Fillings or auxiliary members in containers or encapsulations, e.g. centering rings H01L23/42, H01L23/552 take precedence
• CPC Class Codes: H01L 23/24 solid or gel at the normal operating temperature of the device H01L23/3135 takes precedence
• CPC Class Codes: H01L 24/37 of an individual strap connector
• CPC Class Codes: H01L 24/40 of an individual strap connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/83 using a layer connector
• CPC Class Codes: H01L 24/84 using a strap connector
• CPC Class Codes: H01L 25/072 the devices being arranged next to each other
• 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 2924/00012 : 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 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/0102 : Calcium [Ca]
• CPC Class Codes: H01L 2924/01029 : Copper [Cu]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01042 : Molybdenum [Mo]
• CPC Class Codes: H01L 2924/01076 : Osmium [Os]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/1301 : Thyristor
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/181 : Encapsulation

Abstract

A semiconductor power module includes a plastic housing, a ceramic substrate with upper and lower surfaces being disposed in the housing, upper and lower metallizations respectively disposed on the upper and lower surfaces of the substrate, components disposed on the upper metallization, at least one support having upper and lower parts and being disposed on the substrate in the housing, a first elastomeric soft casting compound disposed in the housing covering the substrate and the lower part of the at least one support, the upper part of the at least one support protruding from the first casting compound, and a second thermo-setting hard casting compound covering the upper part of the at least one support and connecting the upper part to the housing.

Claims

1. Semiconductor power module, comprising a cap-shaped plastic housing, a ceramic substrate with upper and lower surfaces being disposed in and forming a bottom surface of said housing, upper and lower metallizations respectively disposed on said upper and lower surfaces of said substrate, components disposed on said upper metallization, at least one support having upper and lower parts and being disposed on said substrate in said housing, a first elastomeric soft casting compound disposed in said housing covering said substrate and said lower part of said at least one support, said upper part of said at least one support protruding from said first casting compound, and a second thermo-setting hard casting compound covering said upper part of said at least one support and connecting said upper part to said housing.

3. Semiconductor power module according to claim 1, wherein said at least one support is formed of insulating material having a smaller coefficient of expansion than said plastic housing and said casting compounds.

5. Semiconductor power module according to claim 1, wherein said at least one support is formed of ceramic insulating material having a smaller coefficient of expansion than said plastic housing and said casting compounds.

7. Semiconductor power module according to claim 1, wherein said housing has ribs formed thereon at least above said at least one support for frictionally connecting said at least one support to said housing, and said at least one support and said ribs define a gap therebetween filled with said second casting compound.

9. Semiconductor power module according to claim 1, including cement fixing said at least one support to said substrate prior to casting.

12. Semiconductor power module according to claim 1, including pins soldered on said substrate, said at least one support being disposed on at least one of said pins prior to casting.

15. Semiconductor power module according to claim 1, wherein said substrate has a slightly convex curvature, as seen from said lower surface thereof.

2. Semiconductor power module, comprising a cap-shaped plastic housing, a ceramic substrate with upper and lower surfaces being dispposed in and forming a bottom surface of said housing, upper and lower metallizations respectively disposed on said upper and lower surfaces of said substrate, components disposed on said upper metallization, at least one support having upper and lower parts and being disposed on at least one of said components in said housing, a first elastomeric soft casting compound disposed in said housing covering said substrate and said lower part of said at least one support, said upper part of said at least one support protruding from said first casting compound, and a second thermo-setting hard casting compound covering said upper part of said at least one support and connecting said upper part to said housing.

4. Semiconductor power module according to claim 2, wherein said at least one support is formed of insulating material having a smaller coefficient of expansion than said plastic housing and said casting compounds.

6. Semiconductor power module according to claim 2, wherein said at least one support is formed of ceramic insulating material having a smaller coefficient of expansion than said plastic housing and said casting compounds.

8. Semiconductor power module according to claim 2, wherein said housing has ribs formed thereon at least above said at least one support for frictionally connecting said at least one support to said housing, and said at least one support and said ribs define a gap therebetween filled with said second casting compound.

10. Semiconductor power module according to claim 2, including cement fixing said at least one support to said at least one component prior to casting.

11. Semiconductor power module according to claim 2, including compensation discs disposed on said components, and cement fixing said at least one support to at least one of said compensation discs prior to casting.

13. Semiconductor power module according to claim 2, including pins soldered on said at least one component, said at least one support being disposed on at least one of said pins prior to casting.

14. Semiconductor power module according to claim 2, including compensation discs disposed on said components and pins soldered on at least one of said compensation discs, said at least one support being disposed on at least one of said pins prior to casting.

16. Semiconductor power module according to claim 2, wherein said substrate has a slightly convex curvature, as seen from said lower surface thereof.