Effects of Nitrogen Partial Pressures During RF Magnetron Sputtering on the Crystal Structure and Growth Rate of c-BN Films

Abstract

The type of atmospheric gases used in sputtering deposition is an important factor in the formation of cubic boron nitride (c-BN) films. All of the c-BN films were deposited on a Si wafer using radio frequency (r.f.) magnetron sputtering with a B4C target at N2/Ar+N2 ratios of 0.2, 0.4, 0.6, 0.8 and 1.0. The characteristics of the c-BN layer were significantly enhanced at a nitrogen partial pressure of 0.6. The highest growth rate of the c-BN layer was measured at 11.6 (nm/min) at a nitrogen partial pressure of 0.6.The lowest surface roughness was obtained at a nitrogen partial pressure of 0.6 when the BCN gradient layer was clearly deposited. According to the XPS results, the c-BN phase structure improved while the BCN gradient layer was clearly observed. Overall, the growth rate, surface roughness and crystal structure of the c-BN films are significantly affected under certain atmospheric gas conditions such as at a nitrogen partial pressure of 0.6.