| 摘要 |
PURPOSE:To prevent the decline of a film forming velocity by making a light transmittance higher by providing the window formed in a reactor with a light focusing property. CONSTITUTION:A window 20 comprises a light focusing property. A material gas is introduced into a reactor 11 from a material gas introducing pipe 15 and high-energy beams B are projected from a beam source 17. The parallel beams B whose width is extended enter over the relatively wide region of the window 20 and are focused in the reactor 11. Then in the vicinity of the substrate (A) located near the focusing point, a light intensity becomes higher and a photochemical reaction of the material is carried out actively. Meanwhile, in the vicinity of the window 20, a light intensity is relatively weak so that a photochemical reaction does not progress. Consequently, a film is deposited only on the substrate (A) and not on the window 20 so that the light transmitting property of the window can be maintained well after a long-time use. |
