New Technique for Preparation of BiSrCaCuO Thin Films with Tc of 100 K and Above

Abstract

The successful growth of superconducting BiSrCaCuO thin films has been reported by a new process based on rf magnetron sputtering. The formation of a partially melted underlayer by controlling the substrate temperature during an early stage of the deposition process appeared to be responsible for a marked improvement in T _c. A zero-resistance temperature of 100 K and above was achieved with very high reproducibility when the film was deposited on MgO(100) substrate using a target of Bi_1.3Sr₁Ca₁Cu_1.5O _x followed by annealing at 875°C for 0.5 h.