Simultaneous phase separation and basal-plane atomic ordering in InxGa1−xN

Reported discrepancy of phase separation in InxGa1−xN films between experimental studies and theoretical calculations based on the usual regular solution model is discussed from the standpoint of phase diagram. The inclusion of higher-order pairwise interactions in the theoretical model may allow the system to undergo a spinodal decomposition in an asymmetrical manner as revealed by experiments. It is suggested that basal-plane atomic ordering in the In-rich precipitates should accompany the decomposition.