公开(公告)号：US20220223470A1

公开(公告)日：2022-07-14

申请号：US17657521

申请日：2022-03-31

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Roshan Jayakhar TIRUKKONDA ,  Monica TITUS ,  Senaka KANAKAMEDALA ,  Raghuveer S. MAKALA ,  Rahul SHARANGPANI ,  Adarsh RAJASHEKAR

IPC: H01L21/768 ,  H01L21/306

Abstract: A method of forming a structure includes forming an alternating stack of first material layers and second material layers over a substrate, forming a mask layer over the alternating stack, forming a cavity in the mask layer, forming a first cladding liner on a sidewall of the cavity in the mask layer, and forming a via opening the alternating stack by performing an anisotropic etch process that transfers a pattern of the cavity in the mask layer through the alternating stack using a combination of the first cladding liner and the mask layer as an etch mask.