Radiation damage effects in ion-implanted Bi-Sr-Ca-Cu-O superconducting thin films

Abstract

Transition temperature (Tc) control and annealing effects of Bi2.0Sr1.4Ca1.8Cu2.2Oy superconducting thin films implanted by 200 keV Ne+ have been investigated. Tc end points for 0.4-μm-thick Bi2.0Sr1.4Ca1.8Cu2.2Oy films for 0, 1×1012, and 1×1013 ions/cm2 doses are 78, 76, and 54 K, respectively. The ion dose, to achieve a nonsuperconductor for Bi2.0Sr1.4Ca1.8Cu2.2Oy films, is two or more orders of magnitude lower than that for YBa2Cu3O7−x films. The c-lattice constant increases were observed for the implanted films. Moreover, it was confirmed that the superconducting characteristics for the implanted films are recovered by annealing in O2 atmosphere.