Reflection and transmission secondary emission from GaAs

摘要

Reflection and transmission secondary‐emission ratios have been measured for a 3.5‐μm‐thick self‐supporting GaAs film activated to negative electron affinity. A reflection‐mode gain of 540 at 20 keV primary energy was observed. In transmission, the gain at 20 keV primary energy was 112. Analysis of the data gives the surface‐escape probability as 0.18 and the electron‐diffusion length as 3.0 μm. The data are well described by a simple diffusion‐transport model.