公开(公告)号：US11637119B2

公开(公告)日：2023-04-25

申请号：US17134938

申请日：2020-12-28

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Kohei Yamaguchi ,  Keisuke Shigemura ,  Kengo Kajiwara

IPC: H01L27/11575 ,  H01L27/11556 ,  H01L23/00 ,  H01L27/11582 ,  H01L27/11529

Abstract: A row of backside support pillar structures is formed through a first-tier alternating stack of first-tier insulating layers and first-tier sacrificial material layers. At least one upper-tier alternating stack can be formed, and memory stack structures can be formed through the alternating stacks. A backside trench can be formed through the alternating stacks selective to the row of backside support pillar structures. The sacrificial material layers are replaced with electrically conductive layers, and the backside trench can be filled with a backside trench fill structure, which includes the row of backside support pillar structures. The row of backside support pillar structures reduces or prevents tilting or collapse of the alternating stacks during replacement of the sacrificial material layers with the electrically conductive layers.