Design and Construction of a Scanning Tunneling Microscope for Atomic Scale Imaging of Surfaces in Ultra-High Vacuum
The goal of this research project was to design and build a scanning tunneling microscope to be used in the ultra-high vacuum based surface analysis system in the Surface Science Laboratory at Texas State University-San Marcos. The instrument that was constructed is designed to produce atomic-scale images on single crystal samples and to allow transfer of samples to the horizontal manipulator of the system for surface preparation and high-resolution electron energy loss spectroscopy measurements. The outer layer of atoms of most materials either relax or reconstruct, which often results in a change in the electronic, magnetic, and/or chemical properties. Therefore, it is important to be able to characterize the geometric structure of the surface of a material if one is to understand the effect of surface interactions. The main body of the scanning tunneling microscope is constructed from Macor, which is a machinable ceramic. Macor is ultra-high vacuum compatible and has a high strength to weight ratio, low thermal expansion coefficient, and low thermal conductivity, which are all properties desirable for atomic scale imaging. The instrument is mounted on springs with a 13" extension length, which gives it a resonant frequency of less than 1 Hz for vibration isolation. The tube scanner is mounted to an ultra-high vacuum compatible inchworm for coarse and fine approach of the tip to the sample surface. Custom designed analog electronics and software are used to control the instrument.
Scanning, Tunneling, Microscope, Atomic scale, Surface imaging, Ultra High Vacuum
Kilbourn, R. (2010). <i>Design and construction of a scanning tunneling microscope for atomic scale imaging of surfaces in ultra-high vacuum</i> (Unpublished thesis). Texas State University-San Marcos, San Marcos, Texas.