Growth of epitaxial Pt thin films on (001) SrTiO_3 by rf magnetron sputtering

摘要

The growth of platinum thin film by rf magnetron sputtering on SrTiO_3(001) substrates for oxide based devices was investigated. Platinum films grown at temperatures higher than 750 ℃ were epitaxial ([100]Pt(001)//[100]STO(001)), whereas at lower temperatures Pt(111) films were obtained. The surface morphology of the Pt films showed a strong dependence on the deposition temperature as was revealed by atomic force microscopy (AFM). At elevated temperatures there is a three-dimensional (3D) growth of rectangular atomically flat islands with deep boundaries between them. On the other hand, at low deposition temperatures, a two-dimensional (2D) layered growth was observed. The transition from 2D to 3D growth modes was observed that occurs for temperatures around 450 ℃. The obtained epitaxial thin films also formed an atomically sharp interface with the SrTiO_3(001) substrate as confirmed by HRTEM.