Patent ID: 6649434
Filing Date: 2003-11-18
Classification: C30B,H01L

Abstract:
A method of manufacturing a semiconductor device having a ZnO based oxide semiconductor layer, comprising the steps of:growing a buffer layer made of a ZnO based oxide semiconductor on a substrate having a coefficient of thermal expansion which is different from that of a ZnO based oxide semiconductor, at a lower temperature than a high temperature of 500Â° C. or more, before the growth of said ZnO based oxide semiconductor layer, stopping the supply of an oxygen and raising the temperature of said substrate to said high temperature to grow said ZnO based oxide semiconductor layer, growing hetero-epitaxially said ZnO based oxide semiconductor layer on a substrate having a coefficient of thermal expansion which is different from that of a ZnO based oxide semiconductor, at a said high temperature of 500Â° C. or more, and stopping the supply of an oxygen and cooling gradually until the temperature of said substrate is towered to 350Â° C. or less after the growth of said ZnO based oxide semiconductor layer is completed.