Study on Sintering Conditions Affecting Infiltrability of Cr – Cu Heat-sink for Semiconductor Devices

Abstract

Cr – Cu materials have been developed for heat-sink application using P/M processing: Cr powder is sintered and Cu infiltrated. W – Cu and Mo – Cu materials, with low thermal expansion and high thermal conductivity, have been used for heat-sink application. However parts of these materials are produced using expensive powders. Chromium is also a strong candidate for the heat-sink application, because it is the same 6A group element as W and Mo, its powder price is lower and more stable. Cr – Cu materials have succeeded in substitution for W – Cu and Mo – Cu materials. For the heat-sink application, pore free and inclusion free structure of Cr – Cu infiltrated compact is essential for the ability of the following processes: rolling, pressing and Ni plating, to make heat-sink parts. Carbon and oxygen contents of sintered Cr are found to have an effect on the infiltration ability. For the pore free and inclusion free structure, carbon content and oxygen content of sintered Cr should be lower than 0.01 mass% respectively.