Effects of rf bias voltage and H2 flow rate on the growth of cubic boron nitride films by chemical vapor deposition

Cubic boron nitride (cBN) films were deposited by rf bias-assisted dc plasma-jet chemical vapor deposition. Effects of H2 flow rate and bias voltage on the growth of the cBN films were investigated. High phase purity cBN (over 90%) can be obtained in a wide range of H2 flow rates of 5–10 sccm and bias voltages from -50 to -100 V. Nearly phase pure cBN films were deposited at a H2 flow rate of 10 sccm and bias voltages of -60 V and -70 V. The deposited films were characterized by Raman spectroscopy, Fourier-transform infrared spectroscopy, and glancing angle X-ray diffraction. Raman peaks were observed for all the cBN films, which indicate a good crystallinity of the films.