Photoluminescence Spectra of Heavily Si-doped GaAs at Low Temperature

Photoluminescence spectra of heavily Si-doped GaAs grown by molecular beam epitaxy (MBE) were investigated at 20K as a function of electron concentration. We found that the two peaks in the electron populations of the conduction band and the donor band, respectively, are merging as the doping concentration increases, and can not be distinguished at the electron concentration of the order of 10¹⁸ cm ^-3. And we discriminated the artifact peak at 1.49eV from the recombination peak by observing its temperature dependent behavior.