PURPOSE: To stably form a thin film uniform in thickness on a substrate by measuring the film thickness at the intermediate point of a thin film depositing zone and adjusting the final film thickness by feedback control.
CONSTITUTION: A substrate 41 is continuously transferred in a vapor deposition chamber 11, and the substrate 41 on which a thin film is formed is irradiated with the light from a light emitting element 21 consisting of the tip of an optical fiber, etc. The light is received by a light receiving element 13, and the transmittance is measured by a transmission type film thickness monitoring device 25. The measured thickness is compared with a reference value in a controller 31, and a final film thickness correcting plate 19 is opened or turned in the closing direction to change the distance of a film forming zone. Otherwise, the transfer speed of the substrate 41 or the vaporization rate of a thin film forming material from a vaporization source is controlled.
MATSUMOTO SHIGEJI
ZAISHO SHINICHIRO
