Influence of IR Radiation on the Electron Mobility in Submicron Layers of GaAs

The influence of optical radiation near the impurity absorption band on the electron mobility in submicron doped gallium arsenide layers formed on semiinsulating substrates is investigated. To determine the lowfield mobility of carriers, a method is used which is based on measurements of the mutual conductance and series resistances of a fieldeffect transistor at low sourcetodrain voltage. It has been established that the electron mobility increases under IR illumination as a consequence of decrease in electron scattering, and this is related to the photoneutralization of deeplying chrome acceptors.