A DFT study of STO adsorption on GaN (0 0 0 1) surface

Abstract

The adsorption of molecule STO on GaN (0001) surface is theoretically explored by using a plane wave ultra-soft pseudo-potential method based on density functional theory. The simulated results indicate two O atoms are combined with two Ga atoms on GaN surface after adsorption respectively. The O–O line direction lies along the GaN [11−20] directions, and the Sr–Ti line direction lies along the GaN [10−10] directions, in accordance with experimental reports of (111) [1−10] SrTiO3 // (0001) [11−20] GaN. For the total interface energy of STO/GaN, the chemical interaction energy is dominant as the chemical bonding energy achieved 10.215–10.299eV.