Study of Temperature Dependence of Island Formation and Structure of Gallium Nitride in MBE Growth

Homoepitaxial growth on gallium nitride substrate is simulated by molecular dynamics (MD) method. Crystal growth configuration is evaluated qualitatively according to the atomic configuration and the radial distribution function. Moreover, crystal structure is evaluated quantitatively by considering variance of local atomic density as a monitoring index. As a result, we found that the growth layer is formed two-dimensionally and like film formation when the substrate temperature is high. It is found that the dynamics of crystal growth can be understood from not only variance value but also gradient of temporal evolution of variance.