PREPARATION OF CUBIC BORON-NITRIDE FILMS BY LOW-PRESSURE INDUCTIVELY-COUPLED PLASMA-ENHANCED CHEMICAL-VAPOR-DEPOSITION

Cubic boron nitride (c-BN) films have been prepared by low pressure inductively coupled plasma-enhanced chemical vapor deposition (ICP-CVD). 13.56 MHz ICP was generated inside a 38 mm diam tube by supplying 7 kW rf power at 1 X 10(-3) Torr. Films were deposited on Si(100) substrates from the B2H6+N-2+He+Ar system at 900 degrees C. Polycrystalline c-BN films with the grain size less than 50 nm were deposited with the proper ion bombardment of the growing surface. The presence of cubic phase of boron nitride has been confirmed by both infrared absorption spectroscopy and electron diffraction patterns. The optimum sheath potential for c-BN growth in this work was revealed to be 80-86 V.