SUSCEPTOR FOR VAPOR GROWTH

PURPOSE:To upgrade quality of products and to improve productivity by reducing cooling time after vapor growth by a method wherein an outer periphery of a susceptor is thickened and the thickness thereof is stepped down toward an inner periphery. CONSTITUTION:A susceptor 31 is heated uniformly even at the heat-up time when power supply is high, since an outer periphery A of a work coil 20, whose electric power density is high, is thick and an inner periphery B, whose electric power density is low, is thin by means that the outer periphery A there of is thickened and the thickness of the undersurface is stepped down toward the inner periphery thereof. After vapor growth, when the susceptor 31 is cooled by carrier gas, the outer periphery a is cooled quickly because of the presence of an exhaust vent 25 and meanwhile cooling rate of the inner periphery B, whose cooling rate is slow, is hasty, therefore, whole cooling rate comes to be hasty. Thereby, generation of strip is restrained and high-quality vapor growth is possible.