Thermodynamic analysis for nonpolar III-nitride surfaces under metalorganic vapor-phase epitaxy conditions

We perform an improved thermodynamic analysis of nonpolar (1 (1) over bar 00) and (11 (2) over bar0) surfaces for AlN and GaN to elucidate the difference in growth condition among various types of nonpolar and polar surfaces during metalorganic vapor-phase epitaxy (MOVPE). It is found that the maximum growth temperature of (1 (1) over bar 100) surface is lower than those of (0001) and (000 (1) over bar) surfaces. In contrast, the maximum growth temperature of (11 (2) over bar0) surface is high compared to that of (0001) surface. This orientation dependence corresponds to the relative stability between polar and nonpolar reconstructed surfaces. These results offer a way to provide the optimum growth conditions of AlN and GaN for the MOVPE. (c) 2020 The Japan Society of Applied Physics