| 摘要 |
PROBLEM TO BE SOLVED: To provide a film deposition apparatus by which a dense film quality hardly causing cracks or chippings is easily attained by optimizing the flow conditions of a raw gas, so as to easily create a flat optical surface. SOLUTION: The defects in rugged shape generated during mechanical processing after film deposition is suppressed by allowing the cross section of an inner tube 9 in the flow direction of the raw gas to have a rotational symmetry shape so as to suppress the remaining of the raw gas in the inner tube 9 and to enhance the film deposition speed when thermal CVD is performed. COPYRIGHT: (C)2008,JPO&INPIT |
