Consistent Operation of the Houghton College Deposition Chamber
An apparatus constructed to consistently and systematically deposit thin metal films using thermionic emission has been refined. A turbo pump lowers the base pressure of the deposition chamber to 10-6 Torr. Thermionic emission is achieved via current passing through a tungsten filament that is held at -4 kV relative to the desired deposition material. Multiple refinements were made to the apparatus' high voltage circuit to improve the consistency of operation, primarily the securing of multiple connections within the circuit. Additionally, two 2 kV microwave transformers, and four diodes used to produce a doubling rectifier were replaced, and a capacitor bank was added to further refine the output of the forementioned circuit. While production of a thin metal film has yet to be achieved, the high voltage power supply is capable of consistently maintaining a high negative potential to facilitate the production process. Future work and modifications of the apparatus are also discussed.