ALUMINA SUBSTRATE

文件类型：PDF文档
文件大小：79K
PROBLEM TO BE SOLVED : To provide an alumina substrate that has an AlN layer formed and is reduced in warpage, and to provide a substrate material that has large strength enough to withstand ordinary handling when an AlN crystal etc., is raised on the substrate and prevents the raised crystal from cracking or breaking in spite of stress applied during the raising or cooling. SOLUTION : The present invention relates to an alumina substrate having an AlN layer formed on a surface and also having a rare earth-containing region and a gap formed in the AlN layer or between an AlN layer and alumina substrate boundary surface. The rare earth-containing region can reduce warpage of the AlN layer through concentration of grating inconsistent stress or as the gap releases stress. Further, an origin and propagation of cracking and breaking can be guided by the rare earth-containing region because of stress concentration and by the gap because of mechanical strength decrease, and consequently cracking to and breaking of a crystal raised on the substrate can be prevented. Further, the rare earth-containing region can secure mechanical strength substantially against stress of handling. SELECTED DRAWING : Figure 1 COPYRIGHT : (C)2017, JPO&INPIT