Title :
Photocathode performance measurements for the SLC polarized electron gun
Author :
Garden, C.L. ; Hoyt, E.W. ; Schultz, D.C. ; Tang, H.
Author_Institution :
Linear Accel. Center, Stanford Univ., CA, USA
Abstract :
A low-voltage test system is used to qualify various III-V semiconductor materials as photocathodes for the SLC. The system features a load lock to introduce samples, high pumping speed, a sensitive residual gas analyzer, and an infrared temperature detector. Heat cleaning, cesiation, and oxidation procedures have been studied to optimize cathode activation for achieving an optimum NEA surface. VGF GaAs, MBE-grown AlGaAs, MBE GaAs layered on AlGaAs, and MOCVD GaAsP cathodes with different active layer thicknesses and doping concentrations have been tested for quantum efficiency and lifetime. New higher-polarization strained-layer GaAs and GaAsP photocathodes have also been tested. Results and operational experience are discussed
Keywords :
electron guns; gallium arsenide; photocathodes; AlGaAs; Cs; GaAs; GaAs layer; GaAsP; III-V semiconductor; MBE-grown AlGaAs; MOCVD GaAsP; SLC polarized electron gun; VGF GaAs; cathodes; heat cleaning; lifetime; oxidation; photocathodes; quantum efficiency; strained-layer GaAs photocathodes; strained-layer GaAsP photocathodes; Cathodes; Gallium arsenide; III-V semiconductor materials; Infrared detectors; Materials testing; Measurement; Polarization; Semiconductor device testing; Semiconductor materials; System testing;
Conference_Titel :
Particle Accelerator Conference, 1993., Proceedings of the 1993
Conference_Location :
Washington, DC
Print_ISBN :
0-7803-1203-1
DOI :
10.1109/PAC.1993.309543
