2K PL topography of silicon doped VGF GaAs wafers

We report on full wafer and small area photoluminescence topography investigations of VGF GaAs:Si wafers. The wavelength-specific images exhibit various correlations and anti-correlations. Intensity variations due to competitive radiative and non-radiative recombination processes are mainly due to stoichiometric fluctuations and can be distinguished from those generated by the variation of the silicon dopant concentration. X-ray transmission topograms allow to identify grown-in defects like precipitates and dislocations and to correlate these with the observed macro- and microscopic luminescence variation patterns.