CRYSTALLINE QUALITIES AND CRITICAL CURRENT DENSITIES OF AS-GROWN BA2YCU3OX THIN-FILMS ON SILICON WITH BUFFER LAYERS

As-grown Ba2YCu3Ox thin films (\lesssim100 nm) have been prepared by rf magnetron sputtering deposited on Si(100) with buffer layers of YSZ and Y2O3/YSZ. Epitaxial growth of Ba2YCu3Ox thin films is confirmed by ion channeling measurements along the (100) directions of the Si substrate showing a χmin of 60% on YSZ/Si, and 6% on Y2O3/YSZ/Si using 2.0 MeV He+. The as-grown films have critical current densities of 104 A/cm2 on YSZ/Si and 106 A/cm2 on Y2O3/YSZ/Si at 77 K. Our results indicate that the superconducting properties of the films are limited primarily by the value of lattice mismatch between the Ba2YCu3Ox and buffer layers. © 1990 The Japan Society of Applied Physics.