公开(公告)号：US12176440B2

公开(公告)日：2024-12-24

申请号：US17518270

申请日：2021-11-03

Applicant: Winbond Electronics Corp.

Inventor： Shang-Rong Wu ,  Ming-Che Lin ,  Chung-Hsien Liu

IPC: H01L21/764 ,  H01L29/49 ,  H01L29/66 ,  H01L29/788

Abstract: A semiconductor structure and a method of forming the semiconductor structure are provided. The method of forming the semiconductor structure includes forming a floating gate layer on a substrate. A trench is formed in the floating gate layer and the substrate. A first dielectric layer is formed in the trench. A second dielectric layer is formed on the first dielectric layer. A third dielectric layer is formed on the second dielectric layer. A first sacrificial layer is formed on the third dielectric layer. A dielectric stack is formed on the first sacrificial layer. A control gate layer is formed on the dielectric stack. The first sacrificial layer is removed to form an air gap between the third dielectric layer and the dielectric stack.