Auger electron spectroscopy analysis for growth interface of cubic boron nitride single crystals synthesized under high pressure and high temperature

Abstract After rapid cooling, cubic boron nitride (c-BN) single crystals synthesized under high pressure and high temperature (HPHT) are wrapped in the white film powders which are defined as growth interface. In order to make clear that the transition mechanism of c-BN single crystals, the variation of B and N atomic hybrid states in the growth interface is analyzed with the help of auger electron spectroscopy in the Li-based system. It is found that the sp 2 fractions of B and N atoms decreases, and their sp 3 fractions increases from the outer to the inner in the growth interface. In addition, Lithium nitride (Li 3 N) are not found in the growth interface by X-ray diffraction (XRD) experiment. It is suggested that lithium boron nitride (Li 3 BN 2 ) is produced by the reaction of hexagonal boron nitride (h-BN) and Li 3 N at the first step, and then B and N atoms transform from sp 2 into sp 3 state with the catalysis of Li 3 BN 2 in c-BN single crystals synthesis process.