LIQUID-NITROGEN-COOLED DRY ETCHING OF YBACUO THIN-FILMS

A new dry etching method has been developed for patterning YBaCuO thin films with less damage, wherein samples are cooled by liquid nitrogen. It is found that the critical current density J(c) of films etched by this cooling method is significantly improved, more than one order of magnitude higher than that for the films etched at 5-degrees-C. Furthermore, it is found that this technique causes less damage to the surface of the YBaCuO films, compared to the etching at 5-degrees-C. This result suggests that the dry etching process with liquid nitrogen cooling is a promising method for the fabrication of high-T(c) superconducting electronic devices of small dimensions.