A new Li-related photoluminescence center, with zero-phonon line at 0.8793eV, was reported. It was created at 550 to 600C in the final stages of the annealing-out of radiation-induced point defects in float-zone material. Isotopic and chemical correlation data established that the center contained Li and C atoms. The overall analysis indicated that the centre was monoclinic (quasi-trigonal) with the electric dipole in the (110) plane, and –10º from [111]. On the basis of the high annealing temperature which was required in order to form the centre, the need for the presence of C in the lattice, the requirement of at least one Li atom and the efficient thermal passivation at room temperature, it was concluded that a probable model for the centre was C radiation damage involving a Li atom. In particular, it was suggested to be an analogue of H-C centres such as the T centre. This would imply the existence of a family of Li-related centres paralleling the H-related centres.

Spectroscopic Study and Structural Characterization of a Li-Related Photoluminescence in Neutron-Irradiated Si. F.Rodriguez, G.Davies, E.C.Lightowlers: Physical Review B, 2000, 62[10], 6180-91