Comparative research on reflection-mode GaAs photocathode with graded AlxGa1−xAs buffer layer

摘要: Abstract The graded Al compositional x Ga 1− As buffer layer can not only form continuous internal electric field from to active but also optimize the interface properties by decreasing misfit dislocations and stacking faults arising lattice mismatch. By measuring spectral response current (SRC) for two reflection-mode (r-mode) designed samples of stationary structure, we find special phenomenon that structure had quite influence at middle wavelength band 550 nm 850 nm, short 400 nm 550 nm, though absorb photon energy band. Through comparative research through SPV before Cs–O activation SRC after activation, well key parameters such as L D , n S v P . For absorption lengths are relative little long band, so optimizations have on photo-excited electrons which mainly excited region in near surface barriers. parameter, back recombination velocity ( ), impact interface. This help study photo-emission theory design r-mode GaAs photocathodes future research.