Abstract
The Ballistic Electron Emission Microscopy (BEEM) capabilities of a Scanning Tunneling Microscope (STM) have been verified. BEEM is used to analyze the characteristics of buried energy barriers and was developed as an extension of scanning tunneling microscopy; hence, the analytical capabilities of BEEM are on a manometer scale. To use BEEM, low-noise Au/Si (001) Schottky diodes have been fabricated. The diodes were macroscopically tested for their electrical properties using conventional current-voltage (I-V) techniques. The same diodes were then placed in an ultra-high vacuum STM system and analyzed with BEEM. The ballistic electron emission microscopy and scanning tunneling microscopy showed some correlation with the topography of the evaporated gold surface. The barrier heights of the diodes were extracted from the ballistic electron emission spectroscopy with the use of a simple one dimensional BEEM current model. Comparison between the barrier heights obtained with BEEM and conventional I-V techniques showed the localized barrier heights to be higher than the macroscopic barrier heights.
Drummond, Mary Alyssa (1997). Demonstration of Ballistic Electron Emission Microscopy / Spectroscopy on the Au/Si (001) system. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1997 -THESIS -D78.