Open AccessNegative Electron affinity GaAs Cathode Activation with CsKTe Thin Film
Author(s) -
M. Kuriki,
Kazunari Masaki
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1350/1/012047
Subject(s) - cathode , electron , materials science , electron affinity (data page) , adsorption , thin film , ion , cathode ray , doping , optoelectronics , analytical chemistry (journal) , chemistry , nanotechnology , molecule , physics , organic chemistry , quantum mechanics , chromatography
Negative Electron Affinity (NEA) GaAs cathode is an unique device which can generate a highly polarized electron beam with circularly polarized light. The NEA surface is conventionally made by Cs and O/NF 3 adsorption on the cleaned p-doped GaAs crystal, but the robustness of the cathode is very limited, so that the electron emission is easily lost by residual gas adsorption, ion back-bombardment, etc. To improve the cathode robustness, NEA activation with a stable thin-film on GaAs surface according to Hetero junction hypothesis has been proposed by the author. An experiment of the NEA activation with CsKTe thin film was carried out at Hiroshima University and a significant electron emission with 1.43 eV photon was observed which strongly suggested NEA activation. The cathode showed 16 to 20 times improvement of lifetime comparing to GaAs activated with Cs and O.