Method of making a planar electrode

摘要

Chemical mechanical polishing (CMP) of thin film materials using a slurry including a surfactant chemical operative to polish high portions of the film being planarized while preventing the polishing of low portions of the film is disclosed. The low portions can be in a step reduction region of a deposited film. The CMP process can be used for form a planar surface upon which subsequent thin-film layers can be deposited, such as an electrically conductive material for an electrode. The subsequently deposited thin-film layers are substantially planar as deposited without having to use CMP. The resulting thin-film layers are planar and have a uniform cross-sectional thickness that can be beneficial for layers of memory material for a memory cell. The processing can be performed back-end-of-the-line (BEOL) on a previously front-end-of-the-line (FEOL) processed substrate (e.g., silicon wafer) and the BEOL process can be used to fabricate two-terminal non-volatile cross-point memory arrays.