UV-irradiation and thermal-annealing studies in amorphous hydrogenated boron nitride thin films

Abstract

Both photoproduction and photobleaching of dangling bonds by uv irradiation and thermal annealing were observed by electron spin resonance (ESR) in amorphous hydrogenated boron nitride. A model involving long-range hydrogen diffusion and hydrogen evolution is proposed to account for the ESR spectral line shapes observed after uv irradiation and thermal annealing. A Gaussian distribution of activation energies for the long-range hydrogen diffusion was used to explain the observed decrease in spin susceptibility after thermal annealing. A best fit to the spin susceptibility data gave an average activation energy of 0.0475 eV and a half-width of this Gaussian distribution of 0.027 eV.