Sputtering Systems:Two sputtering systems have been established to fabricate a variety of thin films, especially the nanostructured films including overlayers, multilayers, granular solids, clusters, etc. Each sputtering system has three guns: two dc guns for conductive targets and one rf gun for conductive or nonconductive targets. The system is computerized to control the positions of the deposited substrates and twelve samples can be prepared in one vacuum run to avoid undesired changes of preparation conditions for one series of samples. The base pressure is about 1~3 x 10-7 Torr, and the preparation conditions, such as Ar pressure during sputtering and the sputtering rates of the targets, can be adjusted by controlling the Ar flow, sputtering power, etc. Currently there are two gas channels, which may be expanded to four channels, and chemical gas reaction sputtering can be performed. The substrate temperature can be varied from room-temperature to about 700°C. Each sputtering system also has one evaporator which can be used to evaporate thin films or fine particles.
Heat Treatment Ovens:Two tube furnaces (Lindberg 54233 and Lindberg 55332) together with vacuum pump stations are available for sample (or target) annealing, doping, and sintering. The Lindberg 54233 oven has an operating temperature of Tmax = 1500°C and a working tube of diameter 2". The Lindberg 55322 oven has an operation temperature of Tmax = 1200°C and a working tube of diameter 2.5". Both ovens have programmed power supplies and the base pressure of the pump stations are about 2 x 10-6 Torr.