Amorphization kinetics in strontium titanate at 16 and 300K under argon ion irradiation

摘要

The accumulation of irradiation-induced disorder in SrTiO3 single crystals irradiated at 16K with 200keV Ar ions has been investigated using Rutherford backscattering spectrometry along the 100 channeling direction and compared with previous results obtained at 300K under identical irradiation conditions. As expected, amorphization at 16K occurs at a much lower fluence than at 300K due to dynamic recovery of irradiation-induced defects at 300K. Utilizing a comprehensive damage accumulation model for analysis of the data, irradiation at 16K results only in the formation of point defects and amorphous pockets, while defect clusters are also formed at 300K. High defect mobility under irradiation at 300K tends to promote recombination and clustering of point defects. These results suggest that defect diffusion processes in SrTiO3 are not thermally active at 16K.