公开(公告)号：US11923453B2

公开(公告)日：2024-03-05

申请号：US17631287

申请日：2020-08-18

Applicant: CSMC TECHNOLOGIES FAB2 CO., LTD.

Inventor： Huajun Jin ,  Chunxu Li

IPC: H01L29/78 ,  H01L29/06 ,  H01L29/40 ,  H01L29/66

CPC classification number: H01L29/7823 ,  H01L29/0611 ,  H01L29/401 ,  H01L29/404 ,  H01L29/66681

Abstract: The present invention relates to an LDMOS device and a method for preparing same. When a field plate hole is formed by etching an interlayer dielectric layer, the etching of the field plate hole is stopped on a blocking layer by means of providing the blocking layer between a semiconductor base and the interlayer dielectric layer. Since the blocking layer is provided with at least one layer of an etch stop layer, and steps are formed on the surface of the blocking layer, at least two levels of formed hole field plates are distributed in a step shape, and lower ends of the first level of hole field plates to the nth level of hole field plates are gradually further away from the drift area in the direction from a gate structure to a drain area.