A Thin Film Coating Plant Using Thickness Monitoring.

The purpose of this project was to modify an existing vacuum system into a thin film coating plant which would also employ film coating plant which would also employ film thickness monitoring that could be carried out during film deposition for proper control and termination of the process. The thickness monitoring processes employed were the optical method of turning value monitoring, and quartz crystal oscillator frequency monitoring. The results indicated that these two methods responded in the expected manner when a film of titanium dioxide was deposited, however, the actual values for the oscillator frequency change and the transmittance at the turning point were not those expected. These errors could be due to a different crystal cut other than AT, or a change in the material index of refraction or chemical composition upon evaporation and subsequent condensation at the substrate. It was recommended, based on the work done during the project, that various equipment upgrade be made and further test deposition runs be accomplished in order to correlate the output of the two monitoring systems. Keywords Thin films, Optical coatings, Thickness, Monitoring, and Vacuum chambers. Theses