The ultra-violet to yellow luminescence ratio was investigated, as a function of dopant concentration, for Si donor concentrations ranging from 5 x 1016 to 7 x 1018/cm3. The experimental results showed that this ratio was approximately constant in the low-excitation regime, and was independent of the dopant concentration. A theoretical model that was based upon rate equations was developed which permitted the prediction of the yellow luminescence defect concentration as a function of the dopant concentration. A comparison of the model with experimental results revealed that the defect concentration increased almost linearly with dopant concentration. This dependence was consistent with the existence of compensating centers such as acceptor impurities, like C, or compensating native defects.

E.F.Schubert, I.D.Goepfert, J.M.Redwing: Applied Physics Letters, 1997, 71[22], 3224-6