APPARATUS FOR MANUFACTURE OF THIN FILM

PURPOSE:To prevent a product thin film from forming without an ultraviolet light transmission window by applying a bias voltage of a direction for separating ion species that the product becomes solid from the window between a first electrode and a second electrode provided on the window. CONSTITUTION:A power source 11 is so provided as to apply a bias voltage to between a first electrode 4 and a second electrode 2 provided near an ultraviolet light transmission window 5. Ion species or active species slightly charged in which reactive product contained in reaction gas becomes solid is separated from the window 5 by a bias voltage applied to between the electrodes 4 and 2. Since oil is not coated on the window 5 like a conventional apparatus, no impurity is mixed in the formed thin film to obtain the film of high quality. Since an ultraviolet light transmission window is not provided, ultraviolet light is effectively used for photochemical reaction to increase the film forming velocity and critical film thickness.