Ozone processing of MBE grown of YBa/sub 2/Cu/sub 3/O/sub 7-x/ films

Results of a new process for producing high-quality thin films of the YBa/sub 2/Cu/sub 3/O/sub 7-x/ superconducting oxide are presented. This process uses a reactive ozone vapor at a molar rate commensurate with evaporated metal rates under true UHV conditions. A film exhibiting a superconducting onset at 87 K and zero resistance at 82 K was obtained. It was c-axis oriented and contained no second phases as determined by X-ray diffraction. The failure to produce good films by depositing BaF/sub 2/ rather than barium in this configuration was noted. YBa/sub 2/Cu/sub 3/O/sub 7-x/ was formed when diatomic oxygen was used in place of the ozone vapor under nearly identical conditions. The use of pure ozone vapor is the key ingredient in this process, which may be useful in producing thin films of the other high transition temperature compounds. >