FILM SURFACE CLEANING METHOD AND DEVICE

PROBLEM TO BE SOLVED: To realize a film which is high in uniformity, reproducibility, and yield by eliminating the effect of contaminants, impurities, and especially boron contamination on the film by a method wherein the surface of the film is irradiated with an energy beam which is specified in wavelength and energy density so as to enable contaminants to be evaporated or to fly away but as not to melt or modify the film. SOLUTION: An SiO2 film is formed as a buffer layer 2 on the top surface of a glass substrate 1 so as to prevent impurities contained in it from being diffused, and an amorphous silicon layer 3 is formed as thick as 30 to 150 nm on the top surface of the glass substrate 1 through a plasma CVD method where silane is used as material gas. A boron 15 is a contaminant. The amorphous silicon layer 3 is irradiated with an XeCl excimer laser 20 as an energy beam of prescribed energy density from above the layer 3. The energy density of the energy beam is varied depending on the quality and thickness of the amorphous silicon layer 3 and set within a range of 50 to 150 mj/cm2 so as not to melt the amorphous silicon layer 3. The density distribution of an energy beam is made to have a convex spatial distribution curve.