The nucleation and growth conditions ofc-BN films were studied in low-pressure inductively coupled plasma enhanced chemical-vapor deposition. The threshold sheath potentials needed for the nucleation and the growth ofc-BN were sustained by two stepVsheathdeposition. The threshold sheath potential for the growthVsheathgwas found to be significantly lower than the threshold value required for nucleationVsheathn.Under our experimental condition, the values ofVsheathgandVsheathnwere found to be 45 and 65 V. ©1997 American Institute of Physics.