公开(公告)号：US20210408114A1

公开(公告)日：2021-12-30

申请号：US16910799

申请日：2020-06-24

Applicant: SANDISK TECHNOLOGIES LLC

Inventor： Jeffrey LILLE ,  Kanaiyalal PATEL

IPC: H01L27/22 ,  H01L43/12 ,  H01L43/02

Abstract: A refractory metal-containing etch stop layer, a ruthenium etch stop layer, and a conductive material layer can be sequentially formed over an electrode layer and a selector material layer. A sequence of anisotropic etch processes can be employed to etch the conductive material layer selective to the ruthenium etch stop layer, to etch the ruthenium etch stop layer selective to the refractory metal-containing etch stop layer, and to etch the refractory metal-containing etch stop layer within minimal overreach into the electrode layer. The selector material layer can be subsequently anisotropically etched without exposure to the plasma of etchant gases for etching the refractory metal-containing etch stop layer and the conductive material layer, which may include a fluorine-containing plasma that can damage the selector material.