Effect of O2 partial pressure on YBa2Cu3O7-δ thin film growth by pulsed laser deposition

YBa2Cu3O7-delta thin films were processed by pulsed laser deposition on (100) LaAlO3 substrates using O-2 partial pressures from 120 to 1200 mTorr. The effect of O-2 pressure on film properties including room temperature resistivities and microstructures was studied for a unique set of deposition parameters. The film quality was observed to remain high over a wide range of O-2 partial pressures, with much less sensitivity to O-2 pressure than previous studies which are compared. For O-2 pressures from 200 to 1200 mTorr, superconducting transition temperatures consistently reached values >91.5 K and transport critical current densities were 3-5 MA/cm(2) (77 K, self-field). It is proposed that less sensitivity of film properties to O-2 pressure is achieved by: (1) reducing the particle velocity of the plume below a critical threshold, and (2) using a deposition temperature of 785 degreesC for adequate surface activation. (C) 2003 Elsevier B.V. All rights reserved.