Valence band splittings and band offsets of AlN, GaN, and InN

First-principles electronic structure calculations on wurtzite AlN, GaN, and InN reveal crystal-field splitting parameters Delta(CF) of -217, 42, and 41 meV, respectively, and spin-orbit splitting parameters Delta(0) of 19, 13, and 1 meV, respectively. In the zinc blende structure Delta(CF) = 0 and Delta(0) are 19, 15, and 6 meV, respectively. The unstrained AlN/GaN, GaN/InN, and AlN/InN valence band offsets for the wurtzite (zinc blende) materials are 0.81 (0.84), 0.48 (0.26), and 1.25 (1.04) eV, respectively. The trends in these spectroscopic quantities are discussed and recent experimental findings are analyzed in light of these predictions. (C) 1996 American Institute of Physics.