Identification of B- K near edge x-ray absorption fine structure peaksof boron nitride thin films prepared by sputtering deposition

Four π ∗ resonance peaks were observed in the B- K near edge x-ray absorption fine structure spectra of boron nitride thin films prepared by magnetron sputtering. In the past, these peaks have been explained as the K -absorption of boron atoms, which are present in environment containing nitrogen vacancies, the number of which is 1-3 corresponding to the three peaks at higher photon energy. However, the authors found that there was a strong correlation between the intensities of these three peaks and that of O- K absorption after wide range scanning and simultaneous measurement of nitrogen and oxygen K -absorptions of the BN films. Therefore, the authors conclude that these three peaks at the higher energy side correspond to boron atoms bound to one-to-three oxygen atoms instead of three nitrogen atoms surrounding the boron atom in the h -BN structure. The result of the first-principles calculation with a simple cluster model supported the validity of this explanation.