公开(公告)号：US12087572B2

公开(公告)日：2024-09-10

申请号：US17598830

申请日：2020-03-26

申请人： Lam Research Corporation

发明人： Bart J. van Schravendijk ,  Soumana Hamma ,  Kai-Lin Ou ,  Ming Li ,  Malay Milan Samantaray

IPC分类号： H01L21/02 ,  H01L21/311 ,  H01L27/088 ,  H01L27/1157 ,  H10B43/20 ,  H10B43/35

CPC分类号： H01L21/0217 ,  H01L21/02164 ,  H01L21/02211 ,  H01L21/02274 ,  H01L21/0234 ,  H01L21/31111 ,  H01L27/088 ,  H10B43/20 ,  H10B43/35

摘要： Disclosed are methods for the formation of silicon nitride (SiN) on only the horizontal surfaces of structures such as 3D NAND staircase. This allows for thicker landing pads for subsequently formed vias. In some embodiments, the methods involve deposition of a SiN layer over a staircase followed by a treatment to selectively densify the SiN layer on the horizontal surfaces with respect to the sidewall surfaces. A wet etch is then performed to remove SiN from the sidewall surfaces. The selective treatment results in significantly different wet etch rates (WERs) between the horizontal surfaces and the sidewalls.

公开(公告)号：US20220181141A1

公开(公告)日：2022-06-09

申请号：US17598830

申请日：2020-03-26

申请人： Lam Research Corporation

发明人： Bart J. van Schravendijk ,  Soumana Hamma ,  Kai-Lin Ou ,  Ming Li ,  Malay Milan Samantaray

IPC分类号： H01L21/02 ,  H01L21/311 ,  H01L27/11578 ,  H01L27/1157

摘要： Disclosed are methods for the formation of silicon nitride (SiN) on only the horizontal surfaces of structures such as 3D NAND staircase. This allows for thicker landing pads for subsequently formed vias. In some embodiments, the methods involve deposition of a SiN layer over a staircase followed by a treatment to selectively densify the SiN layer on the horizontal surfaces with respect to the sidewall surfaces. A wet etch is then performed to remove SiN from the sidewall surfaces. The selective treatment results in significantly different wet etch rates (WERs) between the horizontal surfaces and the sidewalls.