GaAs/AlAs Super Lattice Photocathodes

Abstract

The design of Gallium Arsenide photocathodes has remained almost static since the pioneering work of Antypas et al in 1973/74(1). This is partly because the GaAs photocathode development has been driven by military requirements, and once production has started, the design is frozen to enable products to be standardised.Recent developments in metal organic chemical vapour deposition (MOVPE) enable new cathode structures to be designed.In our case, we are concerned to produce a photocathode with high quantum efficiency over a wide spectral band, to enable us to build photomultipliers and image intensifiers for general scientific applications. ABSTRACTThe design of Gallium Arsenide photocathodes has remained almost static since the pioneering work of Antypas et al in 1973/74(1). This is partly because the GaAs photocathode development has been driven by military requirements, and once production has started, the design is frozen to enable products to be standardised.Recent developments in metal organic chemical vapour deposition (MOVPE) enable new cathode structures to be designed. In our case, we are concerned to produce a photocathode with high quantum efficiency over a wide spectral band, to enable us to build photomultipliers and image intensifiers for general scientific applications.The paper also gives some of the early data on the photo sensitivity and spectral response together with an overview of some of the devices that can be made with these photocathodes.