Valence-band structure of InN from x-ray photoemission spectroscopy

The valence-band structure of clean, high-quality, single-crystalline wurtzite InN thin films prepared with atomic hydrogen is investigated using x-ray photoemission spectroscopy. The In 4 d 5 ∕ 2 semicore level due to the In-N bond is found to lie 16.0 ± 0.1 eV above the valence band maximum. Experimental valence-band spectra are compared with theoretical calculations of the valence-band density of states (VB-DOS), employing density functional theory within the local density approximation with quasiparticle and self-interaction corrections. Agreement between the experimental valence band spectrum and the theoretical VB-DOS is obtained.