TRANSPORT CHARACTERISTICS AND STRUCTURAL-ANALYSIS OF YBA2CU3O7-X THIN-FILMS IMPLANTED WITH ARGON IONS

High-quality epitaxial films of YBa2Cu3O7-x (YBCO) on (100) SrTiO3 substrates prepared by laser ablation deposition are implanted with 100 keV Ar ions. For the purpose of fabricating high-T(c) superconducting devices by ion implantation technology, the Ar ion implantation induced electrical and structural changes on YBCO thin films are systematically studied by measurements of transport properties, X-ray diffraction (XRD), and Rutherford backscattering spectrometry with channeling (RBS-C). The experimental results show that changes in the film induced by ion fluences of 1 x 10(13) to 1 x 10(14)/cm2 can be used to prepare high-T(c) Josephson devices. The high fluence implantation (almost-equal-to 10(15)/cm2) can be used to pattern the YBCO film. XRD and RBS-C analyses indicate that the defects induced by Ar ions at low and moderate fluences are mainly point defects, which exist as interstitials and vacancies. The high fluence implantation results in the amorphization of the YBCO sample.