GROWTH-RELATED STRESS AND SURFACE-MORPHOLOGY IN HOMOEPITAXIAL SRTIO3 FILMS

The lattice parameter and surface morphology of homoepitaxial SrTiO3 f ilms were found to depend on the ambient oxygen pressure during growth . The homoepitaxial layers were grown by pulsed laser deposition with static ambient oxygen pressures of 100, 10, and 1 mTorr. The surface r oughness of the films increased with increasing ambient growth pressur e. In each case, the measured out-of-plane lattice parameter of the fi lm was larger than that of the substrate. The mismatch between film an d substrate increased with decreasing growth pressure. Compressive str esses of similar to 0.28, 1.2, and 2.0 GPa were determined for homoepi taxial SrTiO3 layers deposited at 100, 10, and 1 mTorr, respectively. (C) 1996 American Institute of Physics.