Spectral Response of THM Grown CdZnTe Crystals

The spectral response of several crystals grown by the Traveling Heater Method (THM) were investigated. An energy resolution of 0.98% for a Pseudo Frisch-Grid of 4 times 4 times 9 mm
³
and 2.1% FWHM for a coplanar-grid of size 11 times 11 times 5 mm
³
were measured using
¹³⁷
Cs-662 keV. In addition a 4% FWHM at 122 keV has also been measured on 20 times 20 X 5 mm
³
monolithic pixellated devices. The material shows great potential toward producing large-volume detectors with spectral performance that meets the requirement for high-resolution gamma-ray spectroscopy.