THEORETICAL STUDIES OF THE NATURE OF THE 2210 cm-1 IR ABSORPTION PEAK IN SILICON CRYSTAL CONTAINING HYDROGEN （Ⅲ）——TEMPERATURE EFFECTS OF THE PEAK SHAPEAND THE SYMMETRIC BREAKING OF DEFECT COMPLEX

It is verified that the phonon scattering process and the residual linewidthare the dominant factors of the linewidth of 2210 cm-1 IR absorption peak except the anomalous linewidth at 200 K. By investigating the anomalities of the peak shape and thelinewidth of the peak at 200 K, we put forward a mechanism that the Td symmetry of defect-complex corresponding to the 2210 cm-1 peak can he transferred into the D2d symmetry as temperature rises to above 200 K. The quantitative analysis shows that the V+4H-model is indeed of two states: The Td configuration is stable at temperature lower than 200 K, while the D2d one is stable at temperature higher than 200 K. We can draw the conclusion that the V +4H-model corresponds to the 2210 cm-1 IR absorption peak from the symmetric breaking mechanism, which can quantitatively fit the experimental results.