USE OF THE CATHODOLUMINESCENCE OF ER3-DOPED ALKALINE-EARTH FLUORIDES AS LOCAL THERMAL PROBE()

Cathodoluminescence (CL) of Er3+-doped alkaline earth fluorides is inv estigated in order to elaborate a thermal probe with micrometer spatia l resolution. The green luminescence of Er3+ ions represents a good ca ndidate for such a purpose since this emission is due to the thermally coupled S-4(3/2) and H-2(11/2) levels. The evolution of the CL intens ity ratio from these levels with temperature is found very sensitive o ver a wide range. In order to take into account the heating induced by the electron beam in the target material, Ne develop a numerical mode l based on both Monte-Carlo and thermal calculations. This model allow s the determination of the field of temperature in the region submitte d to excitation in both stationary and non-stationary modes. Using the electron beam as heating source and the CL emission as local probe by exciting areas with different size, we experimentally determine some differences of heating which are very close to those predicted by calc ulations.