Patent ID: 7828898
Filing Date: 2010-11-09
Classification: C23C

Abstract:
1. A CVD apparatus, comprising: a vertical boat extending in a vertical direction and configured to hold plural substrates in a horizontal state such that said substrates are aligned in the vertical direction; an inner tube extending in said vertical direction and configured to surround said boat laterally; an outer tube surrounding said inner tube laterally from outside, said outer tube further covering a top part of said inner tube; a flange holding said inner tube and outer tube at respective bottom ends thereof; a plurality of gas introducing nozzles provided on a flange outer sidewall; a plurality of gas ejection ports connected to respective ones of the gas introducing nozzles and configured to introduce gases from said respective gas introducing nozzles to a mixing space for mixing said gases to form a mixed gas, said mixing space being within the interior of said flange and open to an interior of said inner tube; and a gas evacuation part evacuating a gas in said outer tube to outside thereof; wherein said mixing space is bounded by an inner surface of the flange sidewall, by a bottom surface of the flange and by a guide part on the bottom surface of the flange, such that said gases introduced to said mixing space by said plurality of gas ejection ports are caused to flow as said mixed gas generally parallel to the bottom surface of said flange along the inner surface of said flange sidewall and along a rotary path, said mixed gas being further caused to flow in said inner tube in an upward direction, wherein said guide part includes two rectangular surfaces sharing respective edges with each other, one of said rectangular surfaces being disposed generally concentric with said inner surface of said flange sidewall, the other of said rectangular surfaces being disposed generally perpendicular to said inner surface of said flange sidewall, wherein said flange further comprises a projecting plate projecting from said inner surface of said flange sidewall in a direction toward a center of said flange in a part thereof where at least said guide part is formed, said projecting plate, a bottom surface of said flange inside said sidewall, said inner surface of said flange sidewall and said guide part together bound said mixing space for mixing said gases to form a mixed gas, said mixing space further causing to flow said mixed gas along said inner surface of said flange sidewall.