Substrate temperature dependence of the texture quality in YBCO thin films fabricated by on-axis pulsed-laser ablation

Abstract

In applications of superconducting devices, the crystalline texture of high-quality YBa2Cu3O7-x thin films is of primary importance. The preferred Mentation of the films can be essentially controlled by means of the substrate temperature, Ts. In order to study the dependence of the film texture on different Ts, a series of films were deposited on YSZ substrates by the on-axis pulsed-laser ablation technique. The substrate temperature was varied from 600°C to 800°C while the rest of the growth parameters remained the same. Various analytical techniques, including x-ray diffraction, scanning electron microscopy, micro-Raman spectroscopy and the four-point probe method, were applied to characterize the films At around Ts = 700°C, the best films with the smoothest surface morphology, lowest FWHM of the rocking curve and highest in-plane texture were obtained The resultant Jc in excess of 1 × 106 A cm-2 at 77 K and Tc around 91 K were also achieved at this temperature.