Abstract
In this paper, synthesis of boron nitride single crystals by using temperature gradient method under high pressure was described. Single crystal of cubic boron nitride (cBN), known as next hard material after diamond, was synthesized with highly pure quality as nearly colorless feature by using Ba base solvent, showing cBN' s band-edge luminescence properties. There is, however, still space for the improvement for the size and purity in the cBN crystals. Other kind of solvents, such as Ni-base alloys, was studied so as to clarify the growth feature of obtained cBN crystals as compared to those with conventional alkali base solvent system. On the other hands, it is found that high quality hBN single crystals were obtained by using the Ba base solvent. The crystals exhibit promising feature for the deep ultraviolet light source and also for high quality substrate of graphene electronic devices.
