Polishing of highly oriented YBa₂Cu₃O_7-δ thin films

We report a mechanical/chemical polishing process that facilitates removal of both particulates and segregated second phases from the surface of highly oriented YBa2Cu3O7-δ (YBCO) thin films. The polishing agent was 0.7% HF in deionized water. The method is quick, simple, and self-limiting. The removal process ceases as a smooth surface is obtained. A thin, fluoride containing passivation layer results from the polishing action, but can be removed easily by an oxygen plasma. This process allows for subsequent growth of epitaxial insulating layers (e.g. SrTiO3) or highly oriented YBCO layers. © 1992.