Crystal growth, characterization, and testing of Cd0.9Zn0.1Te single crystals for radiation detectors

This paper describes our recent research in growing large single crystals of Cd0.9Zn0.1Te (CZT) by the vertical Bridgman technique using in-house processed zone refined precursor materials (Cd, Zn, and Te). The grown semi-insulating CZT crystals have shown high promise for high-resolution room-temperature radiation detectors due to their high dark resistivity (~1010 Ωcm), reasonably good charge transport properties [(μτ)e = (2-5) x 10-3 cm2/V] and low cost. The grown CZT single crystals (~2.5 cm diameter and up to 10 cm long) have demonstrated a very low radial Zn concentration deviation, low dislocation densities and Te precipitate/inclusions, and high infrared transmission. Details of the CZT single crystal growth, their physical and chemical analysis, surface processing, nuclear radiation detector fabrication, and testing of these devices are also presented.