Wade, Travis Ph.D. in Interdisciplinary Materials Science, December 2011 Research Information
Ph.D. Dissertation TEM study of nanostructured cold cathode diamond field emitter tips
Ph.D. Thesis Advisors Jim Davidson (Electrical Engineering) and Norman Tolk (Physics)
Committee Members Weng Kang (Electrical Engineering) Charles Lukehart (Chemistry) Kalman Varga (Physics) Greg Walker (Mechanical Engineering)
---------------------------------------- Abstract. This dissertation furthers the understanding of diamond as a material for cold cathode field emission. Although diamond has proven to be an excellent emitter with orders of magnitude more current at lower fields than competing technologies, fabrication yield has been a persistent issue. Irregularities in emission behavior between tips have historically been attributed to anomalies in the fabrication process which results in "sharp" or "less sharp" diamond tips. However, differences are observed in electron emission thresholds even between tips that appear by conventional analysis to be equally well formed. By enabling analysis of the emitter surface and sub-surface, the methods developed herein permit analysis of diamond tip growth and provide a feedback mechanism for optimization of field emitter properties. This dissertation contains first-time measurements of sharp-tipped diamond cold cathode field emitters imaged by transmission electron microscopy. These preliminary observations correlate hitherto unknown diamond cold cathode emitter nanostructure with emission behavior.
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