A comprehensive study was made of various local bonding environments, in bulk material and thin films, by using core-level photo-absorption methods. Certain features which were not present in crystalline samples were found in the absorption spectra of thin films. These were identified as being N vacancies in the hexagonal bonding of BN, N interstitials, and B clusters. Quantitative information on the concentrations and distributions of point defects could be easily deduced from photo-absorption data.

I.Jiménez, A.F.Jankowski, L.J.Terminello, D.G.J.Sutherland, J.A.Carlisle, G.L.Doll, W.M.Tong, D.K.Shuh, F.J.Himpsel: Physical Review B, 1997, 55[18], 12025-37