Professor David J. Sellmyer, Faculty Supervisor
Dr. Shah Valloppilly, Specialist
855 N 16th Street
N. 110 Nanoscience Research Center
University of Nebraska
Lincoln, NE 68588-0298
fax number: 402-472-6148
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.
The E-beam evaporator:
The facility also houses an E-beam evaporator recently purchased from AJA international. The E-beam system is very similar in design to the sputtering system. The system has the following features:
- The system contains four material pockets for deposition of single and multi layers and alloys.
- System can reach a base pressure ~ 5 x 10-9 Torr
- The system can handle 4 inch substrates which can be rotated and heated up to 850°C.
- The system also has a load lock chamber for quick removal and insertion of samples.