Strain relaxation in epitaxial Pt films on (001) SrTiO_3

摘要

The relationship between strain relaxation and microstructure evolution of epitaxial, (001)-oriented Pt thin films on (001) SrTiO_3 substrates is investigated as a function of Pt film thickness. X-ray diffraction shows that the Pt films gradually relax after film coalescence with increasing film thickness. The Pt film surfaces exhibit a cross-hatched surface pattern that increases in amplitude and density with film thickness and is due to progressive relaxation of the lattice mismatch strain by twinning. The potential of these Pt films as bottom electrodes for functional perovskite films is discussed.