Characterization of molecular nitrogen in III-V compound semiconductors by near-edge x-ray absorption fine structure and photoemission spectroscopies

Formation of molecular nitrogen under low-energy nitrogen bombardment of III-V compound semiconductor surfaces has been studied by photoemissionspectroscopy around N 1s core-level and near-edge x-ray absorption fine structure(NEXAFS) around NK edge. Interstitial molecular nitrogen N₂ has been formed in all of the samples under consideration. The presence of N₂ produces a sharp resonance in low-resolution NEXAFSspectra, showing the characteristic vibrational fine structure in high-resolution measurements, and at the same time, a new peak, shifted toward higher binding energies for several eV, in all N 1sphotoemissionspectra.