Electrical and magnetic properties of Si ion implanted YBa2Cu3O7−δ thin films and microbridges

Abstract

Fabrication of superconducting bilayer YBa 2 Cu 3 O 7 À d (YBCO) thin film structure by Si ion implantation and properties of microbridge patterned on that are presented. YBCO thin film of 150 nm thickness was grown on single crystal (100) SrTiO 3 substrate by inverted cylindrical magnetron sputtering. The sample was implanted with 100 keV, 1 Â 10 16 Si ions/cm 2 . Upon implantation with Si, the sample lost its electrical conductivity and diamagnetism while its crystalline structure was preserved after the annealing of the sample. The implanted ions do not alter the overall crystal structure of high temperature superconductor film. This allows the growth of epitaxial superconducting second layer YBCO film on top of the implanted area without using any buffer layer, thus providing an effective method of fabricating multilayer structures. The second layer film and the microbridge patterned by laser writing technique, showed the superconducting properties similar to those of pure YBCO base layer with a reduced critical current density. D

Developing a trilayer processing technique for superconducting Y Ba2Cu3O7−δthin films by using Ge ion implantation

“…The idea of using the ion implantation technique with suitable ion energy and dose for the purpose of creating an insulating layer serving as a separator between the superconducting layers was the main motive of this work. In our previous work, we presented the growth of a bilayer YBCO structure with Si ion implantation [21]. In that study, upon Si ion implantation, the base layer YBCO thin film completely lost its superconductivity and became a semiconductor.…”