摘要 |
PURPOSE:To enable the synthesis of a high-quality large-sized cBN crystal in high efficiency, by arranging a solvent having different eutectic point from BN, a BN-supplying source and seed crystal in plural chambers and applying a temperature gradient along a definite direction. CONSTITUTION:A synthesis chamber is composed of a plurality of chambers 10a, 10b. A BN source 12a, 12b and a solvent 13a, 13b having different eutectic point from BN are placed in each chamber 10a, 10b. Seed crystals 11a, 11b are embedded in respective seed beds 16a, 16b and both chambers 10a and 10b are separated from each other with the seed bed 16a. The synthesis chamber is heated with a heater 14 using an ultra-high pressure generator to form a temperature gradient wherein the top of the solvents 13a, 13b is heated at higher temperature and the seed crystal at the bottom is maintained at a lower temperature. A cBN crystal is grown in each chamber 10a, 10b keeping the above state. |