Secondary emission and photoemission from negative electron affinity GaP : Cs

Abstract

Secondary emission and photoemission measurements have been made on a negative electron affinity (NEA) GaP : Cs sample. An analysis of the photoemission data gives a surface escape factor B =0.33 and an electron diffusion length L =0.2 μm. The secondary emission ratio data extended over the primary energies E_p of 0–14 keV. If the range of the primary electrons R is assumed to be of the form ${\mathrm{R=a\; E}}_p^b\mathrm{\hspace{0.17em}\mu }\mathrm{m}{\mathrm{\hspace{0.17em}(E}}_p\hspace{0.17em}\mathrm{in\; keV})$ , then analysis of the secondary emission data gives a =0.0095 μm and b =2.0.