The room-temperature, band-edge photoluminescence spectra of degenerately doped (n=1, 2, 3, 8, 10*1019 cm-3) and compensated (K=0.05, 0.1, 0.2, 0.3, 0.5) samples have been investigated for identification of the radiative recombination mechanism and to analyse the possibility for a quantitative estimation of the Burstein-Moss shift. The measured spectra consist of two emission bands. The high-energy band (band-edge luminescence) predominates in intensity over the impurity-associated emission band. The spectral shape is discussed in accordance with theoretical ideas that it follows the free electron energy distribution. The calculated curves (over the full range of electron concentration) are in good agreement with the experimental spectra.
