Elimination of Te Inclusions in ${\rm Cd}_{1-x}{\rm Zn}_{x}{\rm Te}$ Crystals by Short-term Thermal Annealing

摘要: The presence of Te inclusions degrades the quality today's CdZnTe (CZT) crystals used for Xand gamma-ray detectors; both their sizes and concentrations densities must be reduced. Over past years, many researchers proposed using long-term annealing (>;24 h) under Cd vapor pressure to reduce or even eliminate visible IR microscopes. We annealed detector-grade CZT samples periods 15 60 min Cd-, Zn-, Te-overpressure in vacuum at 1000-1200 K. determined optimal temperature, duration, atmosphere such high-temperature annealing, typically ~1100 K 0.5-1.0 h. results were very promising eliminating Te-rich inclusions, on twins where are more stable than unperturbed lattice; indeed, we saw almost no whatsoever by transmission microscopy after annealing. note that lower temperatures takes much longer. However, a above ~1170 generates large quantity irregular inclusions. samples' resistance was estimated I-V curves.