Contacts to Bi-Sr-Ca-Cu Oxide Superconducting Thin Films

Abstract

With the discovery of high TC superconducting materials like Yttrium Barium Copper oxide, Bismuth Strontium Calcium Copper oxide and Thallium Calcium Barium Copper oxide, tremendous interest has developed over the past two years in understanding these materials as well as utilizing them in a variety of applications. The thin films of these materials are expected to play an important role in the area of microelectronics, especially for interconnects in integrated circuits, Josephson junctions, magnetic field sensors and optical detectors. The problems involved in the development of thin films are more complex than that encountered in bulk materials l,2. The properties of thin filmsdepend on the deposition method, deposition conditions and substrate material. Various deposition techniques have been developed which include coevaporation, R.F. and D.C. sputtering, Laser ablation, sol-gel method and molecular beam epitaxy. High TC films have been developed on a variety of substrates like strontium titanate,zirconium oxide, masgnesium oxide, silicon dioxide and saphire3,4,5 Most of the work reported so far is characterizing the thin films for transition temperature, critical current density and critical magnetic field. The structural charactrizations are performed by scanning electron microscopy, energy dispersive x-ray analysis, transmission electron microscopy and X-ray diffraction.