USE OF IN-SITU ELLIPSOMETRY TO OBSERVE PHASE-TRANSITIONS DURING BORON-NITRIDE THIN-FILM DEPOSITION

Thin films of boron nitride (BN) were deposited on glass, silicon and silica substrates in a helicon activated reactive evaporation system. Both the hexagonal (h-BN) and the cubic (c-BN) phases of boron nitride have been grown in the system al different operating conditions. The refractive indices of h-BN and c-BN thin films have been measured at t hree wavelengths. The films were monitored using in situ ellipsometry giving detailed information on the growth of each film. In situ ellips ometry has generally confirmed a model for c-BN growth based on compre ssive stress. Control over the formation of both phases of BN has been demonstrated.