公开(公告)号：US20240304717A1

公开(公告)日：2024-09-12

申请号：US18284052

申请日：2021-08-10

Applicant: CSMC TECHNOLOGIES FAB2 CO., LTD.

Inventor： DONG FANG ,  KUI XIAO

IPC: H01L29/78 ,  H01L29/66

CPC classification number: H01L29/7813 ,  H01L29/66484 ,  H01L29/66734 ,  H01L29/7831

Abstract: A semiconductor device having a split gate structure and a method for manufacturing the same. The method includes: obtaining a base formed with a trench; forming a trench wall oxide isolation dielectric on the inner surface of the trench, and forming a split gate by filling the trench with a split gate material; forming a first oxide isolation dielectric on the split gate; forming a silicon nitride isolation dielectric on the first oxide isolation dielectric; filling a second oxide isolation dielectric above the split gate in the trench in the position where the silicon nitride isolation dielectric is not formed; and forming a control gate on the second oxidation isolation dielectric. The isolation structure between the split gate and the control gate is a multi-dielectric structure which has a higher gate-source voltage resistance compared to the those using a single layer of oxide dielectric.