Extremely Low Secondary Electron Emission from Metal/DielectricParticulate Coatings

Isabel Montero, Instituto de Ciencia de Materiales de Madrid
L Aguilera, Instituto de Ciencia de Materiales de Madrid
Leandro Olano, Instituto de Ciencia de Materiales de Madrid
María E. Dávila, Instituto de Ciencia de Materiales de Madrid
V. Nistor, Applied Physics Dep., UAM
L. Galán, Applied Physics Dep., UAM
JR Dennison, Utah State Univesity
Gregory Wilson, Utah State University

Abstract

We have studied the SEY behaviour of a particulate coating composed of a mixture of a metal (aluminum) in solid state contact with a particulate dielectric material (polyimide thermosetting resin). Surface charging, roughness, and volume fraction are utilized as the main parameters to characterize the electron emission behaviour. Apart from the important role played by surface composition in the SEY, the influence of the dielectric volume fraction has demonstrated to be critical to achieve a significant reduction of SEY. it was found that E1 of the particulate sample increased with increasing dielectric volume fraction. An extremely high first crossover energy, E1>1000eV, was obtained after the gold metallization of the metal/dielectric coatings of 0.75 dielectric volume fraction. It is also remarkable that SEY was ~0.2 for E<1000 >eV, the true secondaries appear to be reabsorbed.