Journal of Crystal Growth, Vol.229, No.1, 321-324, 2001
Mechanism of a-c oriented crystal growth of YBCO thin films by ion beam sputtering
In order to verify the critical factor of surface migration on a-c orientations of YBCO thin film growth, the surface roughness of MgO substrates was controlled by plasma cleaning. Then the films were deposited on these substrates at 600 degreesC by ion beam sputtering. The a-phase ratio increases with increasing surface roughness. This strongly supports the surface migration mechanism because the migration is retarded by surface barriers, and then the a-phase growth is enhanced.
Keywords:nucleation;surface processes;migration enhanced epitaxy;physical vapor deposition processes;perovskites;oxide superconducting materials