公开(公告)号：US4927780A

公开(公告)日：1990-05-22

申请号：US415685

申请日：1989-10-02

申请人： Scott S. Roth ,  Bich-Yen Nguyen ,  Philip J. Tobin ,  Wayne Ray ,  E. Petyr Wachholz ,  Glenn Wissen

发明人： Scott S. Roth ,  Bich-Yen Nguyen ,  Philip J. Tobin ,  Wayne Ray ,  E. Petyr Wachholz ,  Glenn Wissen

IPC分类号： H01L21/76 ,  H01L21/316 ,  H01L21/32 ,  H01L21/762

CPC分类号： H01L21/32 ,  H01L21/7621

摘要： An improved LOCOS isolation process is disclosed wherein an oxidizable layer is conformably dieposited to overlie a silicon nitride oxidation mask. In accordance with one embodiment of the invention, a composite layer comprising a buffer layer and an oxidation resistant material is patterned to form an oxidation mask on a silicon substrate. A layer of an oxidizable material is conformably deposited to overlie the oxidation mask. During the oxidation process used to form electrical isolation structures in the substrate, a substantial reduction in lateral oxidation encroachment is realized.