公开(公告)号：US20230164995A1

公开(公告)日：2023-05-25

申请号：US17532015

申请日：2021-11-22

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Kosaku YAMASHITA ,  Yasuaki YONEMOCHI

IPC: H01L27/11582 ,  H01L27/1157 ,  H01L27/11565 ,  H01L27/11556 ,  H01L27/11519 ,  H01L27/11524

CPC classification number: H01L27/11582 ,  H01L27/1157 ,  H01L27/11565 ,  H01L27/11556 ,  H01L27/11519 ,  H01L27/11524

Abstract: An alternating stack of insulating layers and spacer material layers is formed over a substrate. An insulating cap layer is formed thereupon. A memory opening is formed, which has a greater lateral dimension at a level of an upper insulating cap sublayer than at a level of a lower insulating cap sublayer. A memory film and a semiconductor channel material layer is formed in the memory opening. Ions of at least one dopant species is implanted into a top portion of the semiconductor channel material layer. An isotropic etch process etches an unimplanted portion of the semiconductor channel material layer at a higher etch rate than the implanted top portion of the semiconductor channel material layer to form a vertical semiconductor channel.