MORPHOLOGY AND STRUCTURE OF HIGH T_c YBaCuO THIN FILMS

Thin superconducting films of YBa₂Cu₃O_7-Δ have been prepared by magnetron reactive sputter deposition and subsequent heat treatment. The composition of the thin films has been determined by x-ray Bluorescence spectrum analysis, the structure by x-ray diffraction, and the morphology by scanning electron microscope. The results indicated that the crystallization process of the thin films on different substrates are markedly different. Best results are obtained on film deposited on SrTiO₃ substrate, however, there still exists some non-superconducting phase at the grain boundaries making the superconducting phase weakly linked.