Electron-Induced Ionization and Thermalization in CdS Using Optical Beam Deflection Imaging

The spatial dependence of electron energy loss in semiconducting cadmium sulphide has been investigated as a function of incident electron beam energy using time resolved internal optical beam deflection techniques. Spatial resolution of approximately 0.51.im has been achieved. Ionization and direct electron injection have been shown to dominate the response for times less than 200 nsec, with local thermalization due to electron relaxation effects dominating for times less than several microseconds. Thermal diffusion dominates the beam deflection response at longer times. From these measurements thermal diffusion coefficients have been measured and primary electron ranges estimated. Time resolved images of the primary electron interaction volume have been obtained.