skip to main content

Title: Correlation between microstructure and thermionic electron emission from Os-Ru thin films on dispenser cathodes

Osmium-ruthenium films with different microstructures were deposited onto dispenser cathodes and subjected to 1000 h of close-spaced diode testing. Tailored microstructures were achieved by applying substrate biasing during deposition, and these were evaluated with scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray spectroscopy before and after close-spaced diode testing. Knee temperatures determined from the close-spaced diode test data were used to evaluate cathode performance. Cathodes with a large (10-11) Os-Ru film texture possessed comparatively low knee temperatures. Furthermore, a low knee temperature correlated with a low effective work function as calculated from the close-spaced diode data. It is proposed that the formation of strong (10-11) texture is responsible for the superior performance of the cathode with a multilayered Os-Ru coating.
Authors:
;  [1] ;  [2]
  1. Department of Chemical and Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, Kentucky 40506-0046 (United States)
  2. Semicon Associates, Lexington, Kentucky 40510 (United States)
Publication Date:
OSTI Identifier:
22318071
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Vacuum Science and Technology. A, Vacuum, Surfaces and Films; Journal Volume: 32; Journal Issue: 4; Other Information: (c) 2014 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CATHODES; DEPOSITION; ELECTRON EMISSION; MICROSTRUCTURE; OSMIUM; RUTHENIUM; SCANNING ELECTRON MICROSCOPY; THIN FILMS; X-RAY DIFFRACTION; X-RAY SPECTROSCOPY