Cs2 Te photocathode fabrication system at Peking University

A cesium telluride (Cs 2 Te) photocathode with a quantum efficiency of 13% at 253.7 nm (radiant incidence 200 μW/cm 2 ) is fabricated by tellurium and cesium vapor deposition onto a stainless-steel substrate. The cesium telluride cathode will be used to provide a high-brightness electron beam source for the 3+1/2 photo-injector at Peking University. The design of the system, the fabrication procedures and the preliminary experimental results are presented in this paper.