Effects of a Negative Self-Bias on the Growth of Cubic Boron Nitride Prepared by Plasma Chemical Vapor Deposition

Abstract

Microcrystalline cubic BN films have been prepared on a Si substrate by plasma chemical vapor deposition. The formation of the cubic BN phase in the films necessitated an appropriate negative self-bias on the substrate electrode. Effects of the negative self-bias on the growth of the cubic phase were studied. The dependence of the deposition rate and etching rate of the films on a negative self-bias shows that the cubic phase is generated by the precursors of radical or ion species induced by an ion current in a plasma, and the deposition rate is determined by the generation rate due to these precursors and the etching rate of the cubic phase. In contrast with this, the generation rate of the hexagonal BN phase is independent of the ion current in a plasma.