APPARATUS FOR SIMULTANEOUS MEASUREMENT OF MASS CHANGE, OPTICAL TRANSMITTANCE, AND REFLECTANCE OF THIN-FILMS

An apparatus consisting of a vacuum ultramicrobalance and optical equipment for measuring transmittance and front surface reflectance of thin films from 400 to 800 nm is described. Thin films formed on substrates by thermal or reactive evaporation can be heated in reactive gases of different compositions and pressures. As the chemical composition of the film changes, the optical changes in the film can be monitored simultaneously using computerized data collection, control, and analysis.