Temperature dependence of luminescent centre in cathodoluminescence

Cathodoluminescence (CL) as other luminescence phenomena depends strongly on temperature. The effect of temperature on both energy position of CL and its intensity should be considered in experiment analysis. Previous works assume that the radiative recombination is provided only by the direct recombination of excess carriers between the conduction band and the valence band and at room temperature.A calculation model is developed in order to study the influence of temperature on the energy position and the intensity of CL. This model takes into account the electron beam effect and the dependence of optical and electrical material parameters with temperature.These parameters are energy gap, absorption coefficient, diffusion coefficient, diffusion length and intrinsic carriers density. The recombination process depends on temperature, and it may be direct or by the intermediate of recombination centres (traps). In the present paper, the influence of temperature on energy position and CL intensity is examined. A comparison between the numerical results of the model and experimental data for n-GaAs given by the literature is established.