The control of B N and B C bonds in BCN films synthesized using pulsed laser deposition

Abstract

A novel chemical bond transformation from BN to BC was observed in BCN films synthesized using pulsed laser deposition (PLD). BCN film prepared by using green laser (λ=532 nm) induced two IR absorption at 1370 and 800 cm−1. This film was dominated by amorphous carbon phase and sp2 hybridized BN bonds. BCN film deposited using an ultraviolet (UV) laser (λ=266 nm ) induced an addition infrared (IR) absorption at 1250 cm−1. As we deposit BCN film by deep-UV laser (λ=213 nm), the absorption at 1370 and 800 cm−1 disappeared while the absorption at 1250 cm−1 remained. According to X-ray photoelectron spectroscopy (XPS), BC bonds with a carbon rich composition were formed. The formation of BC bonds in BCN films was also sensitive to deposition gas pressure and substrate temperature. Reactive carbon and boron species were needed to enable BC bonds that hybridized the carbon and the BN phases. A low substrate temperature was required to avoid competition with sp2 hybridized pure BN and pure carbon bonds.