High power ceramic on copper package
According to an embodiment of a high power package, the package includes a heat sink containing enough copper to have a thermal conductivity of at least 350 W/mK, an electrically insulating attached to the heat sink with an epoxy and a semiconductor chip attached to the heat sink on the same side as the lead frame with an electrically conductive material having a melting point of 280° C. or greater.
1. A high power package, comprising:
a copper heat sink having a thermal conductivity of at least 350 W/mK;
an electrically insulating lead frame attached to the copper heat sink with an epoxy; and
a semiconductor chip attached to the copper heat sink on the same side as the electrically insulating lead frame with an electrically conductive material having a melting point of 280° C. or greater.
2. The high power package of claim 1 , wherein the copper heat sink comprises a copper alloy.
3. The high power package of claim 2 , wherein the copper alloy is C194 copper alloy.
4. The high power package of claim 1 , wherein the epoxy comprises a polyimide.
5. The high power package of claim 1 , wherein the epoxy is 2 to 5 mils thick.
6. The high power package of claim 1 , wherein the epoxy has a cure temperature of 275° C. or less.
7. The high power package of claim 1 , wherein the electrically conductive material comprises AuSn, AuSi or AuGe.
8. The high power package of claim 1 , wherein the side of the copper heat sink attached to the lead frame is generally planar.
9. The high power package of claim 1 , wherein the lead frame is a ceramic lead frame.
10. The high power package of claim 9 , wherein the ceramic lead frame comprises alumina.
11. A high power package, comprising:
a copper heat sink having a thermal conductivity of at least 350 W/mK;
an electrically insulating lead frame attached to the heat sink with an epoxy;
a semiconductor chip attached to the copper heat sink on the same side as the electrically insulating lead frame with an electrically conductive material having a melting point of 280° C. or greater;
electrically conductive leads attached to the lead frame; and
bonding wires connecting the electrically conductive leads to a side of the semiconductor chip facing away from the heat sink.
12. The high power package of claim 11 , wherein the heat sink comprises a copper alloy.
13. The high power package of claim 12 , wherein the copper alloy is C194 copper alloy.
14. The high power package of claim 11 , wherein the epoxy comprises a polyimide.
15. The high power package of claim 11 , wherein the epoxy is 2 to 5 mils thick.
16. The high power package of claim 11 , wherein the epoxy has a cure temperature of 275° C. or less.
17. The high power package of claim 11 , wherein the electrically conductive material comprises AuSn, AuSi or AuGe.
18. The high power package of claim 11 , wherein the side of the copper heat sink attached to the lead frame is generally planar.
19. The high power package of claim 11 , wherein the lead frame is a ceramic lead frame.
20. The high power package of claim 19 , wherein the ceramic lead frame comprises alumina.