Patent ID: 11944020
Assignee: CROSSBAR, INC.
Field: nan (nan)
Classification: CPC H | IPC H

Claim 10:
11. A semiconductor device, comprising:
a two-terminal resistive switching device, comprising:
a top electrode comprising a material selected from a group consisting of: silver, a silver compound, a silver alloy, aluminum, an aluminum compound, and an aluminum alloy;
a bottom electrode; and
an active region disposed between the top electrode and the bottom electrode;
a buffer material overlaying and in contact with the top electrode of the two-terminal resistive switching device, wherein the buffer material comprises TiN or TaN;
an etch stop material overlaying and in contact with the buffer material, the etch stop material comprising a material selected from a second group consisting of: aluminum, an aluminum compound, and an aluminum alloy; and
a top cap overlaying and in contact with the etch stop material, wherein the top cap comprises an electrically conductive material that is selected from a third group consisting of: TiN and TaN; wherein the semiconductor device is formed by a process comprising:
etching the top cap with a first etch procedure of a two-step etch using a chemical etchant selected from a fourth group consisting of: boron trichloride (BCl3), chlorine (Cl), and a compound comprising Cl, Cl2, or BCl3, and terminating the first etch procedure in response to exposing the etch stop material, wherein the top electrode is substantially free of chlorine impurities from the chemical etchant; and
etching with a second etch procedure of the two-step etch, the second etch procedure comprising a physical etch, a portion of the etch stop material exposed by the first etch procedure and respective portions of the buffer material, the top electrode, the active region and the bottom electrode underlying the portion of the etch stop material exposed by the first etch procedure.