Heteroepitaxial growth of cBN single crystals on the (100) surface of diamond seed crystals under high pressure

摘要

Single crystals of cubic boron nitride (cBN) were heteroepitaxially grown on the (100) surface of diamond seed crystals. The temperature gradient method was applied for crystal growth under static high pressure of 5.5 GPa and high temperature of 1500℃ for 10 mm-100 h using lithium boron nitride as a solvent. Initial growth features of cBN crystals were found on the diamond seed surface after a growing time of 10 mm. Typical antiphase boundaries appeared in the growth pattern, and the single domain became larger as the growing time increased and with the addition of Be as a dopant. According to RHEED measurements on the polished crystal surface, the grown crystals exhibited neither twinning nor superstructure on the surfaces, suggesting a (001)1 × 1 structure. The growth rate of the crystal under constant P-T growth conditions was remarkably small compared with that of diamond.