SUBLIMATION METHOD OF RAW MATERIAL COMPOUND IN CVD FILM FORMATION METHOD

摘要

PROBLEM TO BE SOLVED: To eliminate the fluctuation in film forming speeds by forming a raw material compd. for CVD to a film form, covering its rear surface with a non-reactive supporting object and exposing the other surface to a film forming atmosphere to form the surface for sublimation. SOLUTION: The raw maternal compd. is formed to the thin film shape in the film form and its one surface is fixed to a supporting body and is masked. Since the one surface is fixed, the shape remains stable and the exposed area does not change with lapse of time even if the opposite surface sublimates. Since the area of the sublimation surface does not change, the gas concn. is kept constant without changing. The non-reactive supporting body is a spherical body having the smooth surface and is preferably formed with smooth ruggedness on the surface of this spherical body. The spherical body is preferably packed into a long-sized column and a carrier gas is passed into this column. The non-reactive supporting body may be a rod or pipe having the smooth surface as well. The non-reactive supporting body may be a metallic plate. The high film forming speed is maintained. The strict control of compsn. ratios is possible in the case of components of >=2 elements.