Construction of inverse photoemission spectrometer and its application

Abstract

An inverse photoemission spectrometer has been built and tested. It consists of a photon detector and a low energy electron gun in ultrahigh vacuum chamber (about $10^{-10}$ torr). The photon detector which we have bulit is a band pass photon detector of which resolution is about 0.6 eV at mean photon energy $h_ω$ = 9.8 eV. It consists of an electon multiplier with CuBe cathode and a $CaF_2$ optical cutoff window. The electron gun originally designed by Erdman and Zipf has been constructed. The extractor of the electron optics has been modified to enhance electron beam current. The electron trajectory calculated by ray-tracing program for the electron gun is described. The performance of the electron gun is presented. An isochromat spectrum for uncleaned Si(111) surface was obtained.