Characterization of deep level defects in TI6I4S single crystals by photo-induced current transient spectroscopy

摘要

Defect levels in semi-insulating TI6I4S single crystals grown by the horizontal Bridgman technique have been characterized using photo-induced current transient spectroscopy (PICTS). These measurements revealed six electron traps located at (0.059 +/- 0.007), (0.13 +/- 0.012), (0.31 +/- 0.074), (0.39 +/- 0.019), (0.62 +/- 0.110), and (0.597 +/- 0.105). These defect levels are attributed to vacancies (V-I, V-S) and antisite defects (I-S, Tl-S, Tl-I) upon comparison to calculations of native defect energy levels using density functional theory and defects recently reported from photoluminescence and photoconductivity measurements.