A study was made of luminescence bands that were distributed over energies ranging from 0.5 to 1.0eV, and were known to be dislocation-related. The contribution of various dislocation configurations, as well as dislocation impurity complexes, to the spectrum led to a strong dependence of the relative intensity of individual lines upon the dislocation generation procedure. Particular attention was paid to the low-energy part of the spectrum, which was of great interest in technical applications. Broad photo-emission bands, with energy positions at 0.778 and 0.85eV, respectively, were identified as being due to donor-acceptor pair combinations between O thermo-donors and D1 dislocation acceptors. The temperature dependence, and H passivation, of the transitions were studied. By comparing calculated and experimental spectra, the energy position of the D1 dislocation acceptor was found to be about 0.36eV above the valence band.

E.A.Steinman, V.V.Kveder, H.G.Grimmeiss: Solid State Phenomena, 1996, 47-48, 217-22