Modification of epitaxial oxide films with ion implantation

Abstract

Ion implantation is used to modify the properties of oxide (YBCO and YSZ) thin films. Both superconducting and dielectric epitaxial oxide films, grown by laser ablation, are studied. The properties of the implanted oxide films are characterized by SIMS, XPS, DC resistivity and AC susceptibility measurements. By introducing reactive ions into superconducting oxide films, the conductivity of the material is inhibited possibly due to the interaction of the implanted ions with oxygen originally bound to the copper atoms. Al, Si, Ag and Ca ions are implanted into epitaxial YBCO films with injection energies ranging from 50 - 100 KeV and doses ranging from 1×1015 - 1×1016/cm2. XPS analysis shows that the implanted Si ions form SiOx. The inhibition method has been applied to the fabrication of superconducting electronic devices, such as SQUIDs. Dielectric oxide films are doped by the implantation of conductive and non-conductive ions. YSZ films are doped with Ag and Si ions and the ions are found to increase the conductivity.