Room temperature synthesis of boron nitride thin films by dual-ion beam sputtering deposition

Boron nitride (BN) films are prepared by dual-ion beam sputtering deposition at room temperature (~25°C). An assisting argon/nitrogen ion beam (ion energy Ei=0–300eV) directly bombards the substrate surface to modify the properties of the BN films. The effects of assisting ion beam energy on the characteristics of BN films were investigated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectra, atomic force microscopy, and optical transmittance. The density of the B–N bond in the film increased with the increase in assisting ion beam energy. The highest transmittance of more than 95% in the visible region was obtained under the assisting ion beam energy of 300eV. The band gap of BN films increased from 5.54eV to 6.13eV when the assisted ion-beam energy increased from 0eV to 300eV.