Vertical type vapor-phase growth apparatus

Claim 1

A vertical type vapor-phase growth apparatus comprising a vapor-phase growth reactor constituted of an upper section defining an upper chamber having a lateral cross-section of below 200 cm 2 , a lower section defining a lower chamber having a lateral cross-sectional area greater than, but smaller than four-times the cross-sectional area of, the upper chamber, and a jointing section connecting together the upper and lower sections; a support disposed within the lower chamber and on which a sample is placed, said upper chamber, jointing section and lower chamber lacking gas flow restrictions therebetween; and means for conducting a gas for vapor-phase growth into the upper chamber of the reactor, wherein said support is provided within the lower chamber and near the upper chamber such that an area of a gap as defined between the outer peripheral surface of the support and the inner surface of the reactor and taken in the minimal cross-sectional direction of the gap is made equal to, or smaller than, the lateral cross-section of the upper chamber, wherein said means for conducting a gas into the upper chamber of the reactor comprises gas supply means, a gas introducing duct for supplying the gas from said gas supply means into the upper chamber of the reactor, and gas diffusion means for diffusing the gas from said gas introducing duct, wherein the upper and lower chambers of the reactor are provided concentric with the support, and wherein said support has a silicon plate upon which a sample is directly placed.