Electronic structure of indium nitride studied by photoelectron spectroscopy

Photoemission studies were carried out on indium nitride single crystals. The peaks for N $1s,$ In ${3d}_{5/2},$ and In ${3d}_{3/2}$ were observed with binding energies of 396.0, 443.6, and 451.2 eV, respectively. We observed a valence band with width of 10 eV showing two distinguishable features at binding energy of 3.9 and 7.4 eV. Reasonable agreement for the valence-band width was found between the experimental data and the theoretical results calculated using empirical pseudopotential method.