2.1.1 Overview

For the present, work surfaces for three different applications were investigated:

Start surfaces should exhibit a high secondary electron yield, low angular scattering, and a low UV sensitivity (e.g. low photo electron yield, low UV photon reflection). Stop surfaces on the other hand should exhibit a very high secondary electron yield with no requirements regarding angular scattering. The most challenging surface type is the conversion surface: high ionization yields, low UV sensitivity, low angular scattering, predictable energy loss upon scattering, low energy spreading, and low sputtering are the main requirements.

Ideally a surface would not change its key properties over time, would not require routine reconditioning or special cleaning, and would be easy to handle.

March 2001 - Martin Wieser, Physikalisches Institut, University of Berne, Switzerland