MOLECULAR-DYNAMICS SIMULATION ON A LAYER-BY-LAYER HOMOEPITAXIAL GROWTH-PROCESS OF SRTIO3(001)

The effect of substrate temperature on the homoepitaxial growth proces s of a SrTiO3(001) surface has been investigated using our crystal gro wth molecular dynamics simulation code. SrO molecules were continuousl y deposited one by one on the SrTiO3(001) surface terminated by TiO2 a tomic plane at 300 K. Two-dimensional and epitaxial growth of a SrO th in layer was observed on the SrTiO3(001) surface retaining perovskite type structure and (001) oriented configuration. However, some defects were constructed in the grown film at a low temperature of 300 K, whi ch is in significant contrast to that at 713 K. In the latter case, a single flat and smooth SrO layer was formed without any defects, which is in good agreement with the experimental results. The self-diffusio n coefficient, activation energy for surface migration, and adsorption energy of the deposited SrO molecules on the SrTiO3(001) surface were discussed. A higher migration ability of the deposited SrO molecules at high temperature was found to lead to complete layer-by-layer homoe pitaxial growth. (C) 1998 American Institute of Physics. [S0021-9606(9 8)50243-7].