International Business Machines Corporation
Oxygen-free plasma etching for contact etching of resistive random access memory

Abstract:

A resistive random access memory (RERAM) apparatus and method for forming the apparatus are provided. Oxygen content control in the RERAM is provided. To provide oxygen content control, a via to an electrode of the RERAM is formed utilizing an oxygen-free plasma etch step. In one embodiment, the dielectric within which the via is formed is silicon nitride (SiN). In exemplary embodiments, the plasma chemistry is a hydrofluorocarbon (C.sub.xH.sub.yF.sub.z)-based plasma chemistry or a fluorocarbon (C.sub.xF.sub.y)-based plasma chemistry. In one embodiment, the resistive layer of the RERAM is a metal oxide. In another embodiment, the oxygen concentrations in the electrode of the RERAM under the via and outside the via are the same after formation of the via.