Molecular nitrogen implanted in Al2O3 by low energy N2+ ion bombardment

Alumina subjected to low energy (∼0.5 keV) N2+ ion bombardment stabilizes diatomic nitrogen within its matrix. This is confirmed by near edge X-ray absorption spectra of the N K threshold for the implanted nitrogen species that reveals the typical vibrational structure (with the same vibrational spacing) of molecular gaseous di-nitrogen. The analysis of the N KLL resonant Auger emission spectra of the nitrogen implanted alumina samples is characterized by similar features as those found for N2 in the gas phase. This reaffirms that the incorporated nitrogen in alumina by low energy ion bombardment is in molecular form. The use of resonant Auger spectroscopy is proposed as a general tool to ascertain the formation of di-nitrogen in implanted phases when the photon bandwidth at the N K edge is not narrow enough to resolve the corresponding vibrational structure by X-ray absorption spectroscopy.