公开(公告)号：JPH11163123A

公开(公告)日：1999-06-18

申请号：JP25162198

申请日：1998-09-04

Applicant: MICROCHIP TECH INC

Inventor： AMAND ROGER D ST ,  DEUTSCHER NEIL F ,  MA ROBERT P

IPC: H01L21/316 ,  H01L21/314 ,  H01L21/32 ,  H01L21/76 ,  H01L21/762

Abstract: PROBLEM TO BE SOLVED: To provide a method for forming a narrow thermally oxidized silicon side isolation region in a semiconductor substrate and a MOS or CMOS device. SOLUTION: After a process has been performed for removing bottom sections of openings 20 of a silicon nitride layer 16 and an amorphous polysilicon layer 14, the exposed parts are removed by using the silicon nitride layer 16 as a mask. Then narrow oxidized silicon side isolation regions are grown in the surface of a semiconductor substrate by heating through an opening formed via an oxynitride layer 12. Then the semiconductor substrate is left in such a state that the substrate has the narrow oxidized silicon side isolation regions and the remaining surface section of the substrate is exposed by removing the parts of the silicon nitride layer 16, the amorphous polysilicon layer 14, and the oxynitride layer 12. Following this, a MOS semiconductor device is formed between the narrow oxidized silicon side isolation regions formed in the semiconductor substrate.