Abstract
Greater than 500 cm(3) single crystal CdZnTe (CZT) has been grown using the travelling heater method providing thick ( > 5 mm) detectors required for high energy gamma ray detection. Detectors greater than 5 mm thickness have achieved superior energy resolution or < 1 %FWHM for 662 keV gammas from a (137)Cs source while maintaining this level of resolution for 1.17 and 1.33 MeV gammas from a(60)Co source. Standard, 5 mm thickness detectors also show increases in mobility-lifetime products for both electrons and holes in crystals grown over 3 years. The improvement in these measurable is attributable to improvements in quality of the grown CZT and post growth heat treatments.