The piezospectroscopic analysis of point defects allows to describe fixed defects embedded in a crystal environment of immobile atoms. This description works well when all atoms vibrate around fixed equilibrium positions and these vibrations were much faster than the time scale of the experiment while the equilibrium positions do not evolve within this time scale. For some defects this condition was not fulfilled at temperatures of the deep-level transient spectroscopy experiment, which somehow was reflected in a departure from what the theory predicted. On the other hand, systematic discrepancies between results of theoretical piezospectroscopic analysis and experiment could be a valuable source of information about a defect. It was considered how these re-orientation processes could be identified from the observed piezospectroscopic parameters for a number of defect complexes observed in Si and Ge with the use of the high-resolution Laplace deep level transient spectroscopy.

Piezospectroscopic Analysis of Mobile Defects in Semiconducting Materials. L.Dobaczewski, A.R.Peaker, V.P.Markevich, I.D.Hawkins, K.Bonde Nielsen: Physica Status Solidi C, 2008, 5[2], 529-34