Photoluminescence of silicon thermal donors

All thermal-donor-related photoluminescence (PL) bands, i.e., bound-exciton recombination at neutral thermal donors (1.143 eV), the ${\mathrm{O}}_{\mathrm{J}}$ (1.117 eV) and ${\mathrm{O}}_{\mathrm{J}}^{\prime }$ (1.052 eV) bands, and bound-exciton two-electron (2e) transitions at so-called N-O complexes, were studied in p-type Czochralski-grown silicon substrates doped with boron and aluminum. The influence of aluminum doping on the thermal-donor generation was found to be of secondary importance. For the ${\mathrm{O}}_{\mathrm{J}}$ and ${\mathrm{O}}_{\mathrm{J}}^{\prime }$ bands an interpretation in terms of thermal-donor-related 2e transitions is proposed. For the N-O emission substantial evidence is presented which rules out the possibility of nitrogen involvement. Finally, for Al-doped material, four PL lines, labeled from PL-Si-NL2 to PL-Si-NL5, dominating the spectrum for extended heat-treatment times are reported.