Optical film thickness control device, thin film forming device, optical film thickness control method and thin film forming method

摘要

PROBLEM TO BE SOLVED: To realize highly accurate optical film thickness control even with respect to a temperature change of physical properties of a film-forming substance at the time of film formation, and to improve the accuracy of optical control for arbitrary multilayer film formation. An optical film thickness control device, a thin film forming device, an optical film thickness control method, and a thin film forming method are provided. A control unit 60 employs a reflection amplitude r between an equivalent film and a current layer, a reflection amplitude r0 between a current layer and air, and a fitting function T associated with a phase δ during film formation. The measured value of the change in transmittance with time is fitted in association with the fitting function, the physical parameter of at least one of the phase δ and the equivalent reflection amplitude r at the time of film formation is determined, and the determined physical parameter and the preset theoretical value are determined. The stop time of the current layer is determined so as to match with, and the film formation control that stops the film formation during this stop time is possible, and the film formation control is corrected based on the substrate temperature measured by the temperature measuring unit 70. It is possible. [Selection diagram] Fig. 1