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The purpose of the sputter deposition system is to deposit a uniform film of some material onto a substrate. This process is performed in an evacuated chamber, filled with argon (Ar) at some relatively low pressure. The sputtering guns are controlled by either a Radio Frequency (RF) power supply or a DC power supply. There are two identical guns in the system, located in the bottom rear of the chamber. The target, or the material to be deposited, is a disk of pure material mounted on top of one of the sputtering guns. When the power supply is turned on, a powerful magnetic field causes excited Ar ions to collide with the target surface, removing atoms of material. The atom then moves to the substrate where the film grows. The vacuum is created in the chamber by two pumps used in series. A mechanical pump brings the chamber to an appropriate starting pressure, then the cryopump brings the chamber to the appropriate pressure for the sputtering process. Substrates are placed deposition side down on the rotating tray in the middle of the chamber above the guns. There are many devices available for mounting different sized samples. If the thickness is critical, the in-situ quartz sensor is used to exactly monitor film thickness.