Sintered alumina-zirconia substrate for semiconductor device, has compact obtained by heating composition comprising aluminum oxide, zirconium oxide and/or yttrium oxide powder, and has preset thermal conductivity and flexural strength

摘要

A sintered alumina-zirconia substrate comprises sintered compact obtained by heating a composition comprising mixture of aluminum oxide powder, zirconium oxide powder and/or yttrium oxide powder and free of sintering aid. The sintered compact contains 2-15 wt.% of zirconium oxide, 0.01-1 wt.% of yttrium oxide and remainder of aluminum oxide. The substrate has average crystal grain diameter of more than 2 microns and 7 microns or less, thermal conductivity of 30 W/mK or more and flexural strength of 500 MPa of more. A sintered alumina-zirconia substrate comprises sintered compact obtained by heating a composition comprising mixture of aluminum oxide powder, zirconium oxide powder and/or yttrium oxide powder and free of sintering aid. The sintered compact contains 2-15 wt.% of zirconium oxide, 0.01-1 wt.% of yttrium oxide and remainder of aluminum oxide. The substrate has average crystal grain diameter of more than 2 microns and 7 microns or less, thermal conductivity of 30 W/mK or more and flexural strength of 500 MPa of more. The length of grain boundary having aluminum oxide grains is 60% or more of total grain boundary length. An independent claim is included for manufacture of sintered alumina-zirconia substrate.