Electron temperature and lifetime mapping of photoexcited carrier in semiinsulating LEC GaAs substrates by photoluminescence

The temperature of photoexcited electrons in LEC-grown semi-insulating GaAs is determined by photoluminescence spectroscopy at low temperature. From the electron temperature the carrier lifetime is calculated. We report two-dimensional high resolution (50mym) temperature and lifetime topography of wafers with different annealing history. A strict correlation is found between lifetime and luminescence intensity. The electron temperature and its spatial variation are strongly modified by annealing and are thus useful quality criteria for a quantitative comparison.