Journal of Vacuum Science and Technology
The authors report on electron emission from HfC(310) operating in extended Schottky emission mode. Data are gathered from test stands as well as through operation in a commercial scanning electron microscope. Emitter end-form geometry consisted of rounded, via electrochemical etching, and truncated, via ion milling. The authors demonstrate high angular intensity operation of >60 mA/sr especially for the rounded end-form emitters. Advantages include robustness of the material, which is not reliant on material supply as is the case with standard ZrO/W(100) sources. Hence, operation is available over a much larger range of temperatures, fields, and potentially pressures. Operation in a commercial scanning electron microscope gave ten times higher beam currents for identical operational parameters over a standard Schottky source.
Mackie, William A.; Lovell, Josh M.; Curtis, Todd W.; and Megara, Gerald G., "HfC(310) High Brightness Sources for Advanced Imaging Applications" (2014). Faculty Publications - Department of Mechanical and Civil Engineering. 42.