The ion-assisted, high-rate, reactive and pulsed-DC magnetron sputtering technique was used to deposit boron carbon nitride (BN:C) films by sputtering a boron carbide (B4C) target in argon and nitrogen plasma. Various processing parameters were explored to grow BN:C films with high cubic boron nitride (c-BN) content. FTIR, SEM, TEM, AES, and Raman spectroscopy were used to characterize the phases, composition and surface morphology of the films. Significant influence of substrate bias voltage and temperature on phase composition of the films was found. The deposited BN:C films exhibit h-BN, wurtzite-BN (w-BN), c-BN phases and their mixed phases with the variation in substrate bias and temperature. A multi-stage deposition technique with variable substrate bias was exploited to obtain 90% c-BN film with clear grains and facets.