| 摘要 |
PURPOSE:To segregate a trace amt. of impurities contained in a crystal, and to deposit effectively the impurities on the surface of the crystal by irradiating the surface of the crystal with an energy beam to melt the surface, and then growing crystals at a low solidifying rate. CONSTITUTION:An energy beam such as a laser beam, an electron beam, and an infrared beam is irradiated on the surface of a crystal to melt the surface layer. The crystal is then grown by using the unmolten part as a substrate crystal, and reducing the solidifying rate to nearly an order of magnitude lower than D/a [D is a diffusion coefficient of the impurity atom in molten liquid of mother body, and (a) is the distance between atoms]. The trace amt. of the impurities below detecting sensitivity contained uniformly in the crystal is segregated and deposited on the surface of the crystal in this way, and the analytical measurement can be easily carried out. |
