SIMULTANEOUS PHASE-SEPARATION AND BASAL-PLANE ATOMIC ORDERING IN INXGA1-XN

lReported discrepancy of phase separation in InxGa1-xN films between e xperimental studies and theoretical calculations based on the usual re gular solution model is discussed from the standpoint of phase diagram . The inclusion of higher-order pairwise interactions in the theoretic al model may allow the system to undergo a spinodal decomposition in a n asymmetrical manner as revealed by experiments. It is suggested that basal-plane atomic ordering in the In-rich precipitates should accomp any the decomposition. (C) 1998 American Institute of Physics. [S0003- 6951(98)00948-6].