All Physics Faculty Presentations

Title

Effects of Bandgap on Secondary Electron Emission for Graphitic Carbon Semiconductiors

Document Type

Conference Paper

Journal/Book Title/Conference

Bulletin of the American Physical Society

Volume

48

Publication Date

2003

Abstract

Preliminary data indicates a relationship between bandgap width and magnitude of secondary electron (SE) yield. Our work extends this research to investigate the correlation of small bandgap width to SE yield. These trends are compared with current semiempirical models of two limiting cases, conductors and large bandgap semiconductors. Specifically, five graphitic amorphous carbon (g-C) samples of decreasing bandgap width were produced by vacuum annealing from 0C-1050C. Preliminary data shows a 30of g-C above nanocrystalline graphite. Measurements include SE yields, backscattered yields and electron emission spectra, as well as characterization with SEM, photoyields, AES, resistivity, and Raman spectroscopy. SE yields were taken under UHV with a custom biased hemispherical grid surrounding the sample. Understanding of SE yields have myriad applications including scanning electron microscopy, spacecraft charging, plasma fusion chambers, electron multipliers, and vacuum tubes. *Supported by NASA Space Environments and Effects Program, Air Force Office of Scientific Research, Boeing Corporation, and USU Research Office.

Comments

Bull. Am. Phys. Soc. 48(1) Part II, 1146, (2003). American Physical Society March Meeting 2003, March 6, 2003, Austin, TX.