Measurements of geometric enhancement factors for silicon nanopillar cathodes using a scanning tunneling microscope

High-density silicon nanopillar cathodes were fabricated using a self-assem bling colloidal gold etch mask. Scanning tunneling microscopy experiments w ere performed to locate individual nanopillars and to investigate their fie ld emission properties. Emission characteristics were obtained over a range of fixed separations from the nanopillar apex, allowing the empirical dete rmination of the geometric field enhancement factors from the resulting Fow ler-Nordheim plots. The geometric enhancement factors were found to increas e dramatically for decreasing anode-cathode separation and the rate of incr ease is dependent on the nanopillar geometry. (C) 2001 American Institute o f Physics.