Energy Spectrum Improvement with a CZT Strip Detector

Cadmium zinc telluride (CZT) has been shown to be suitable for use in high-resolution gamma-ray energy spectroscopy and radiation imaging. A low-energy tail appears in the energy spectrum when the high-energy gamma-ray energy spectrum is obtained with a CZT planar detector. This is due to the low charge transport in the crystal. In this study, a CZT detector with strip electrodes was fabricated to reduce the low-energy tail in the energy spectrum. CZT strip detectors with various electrode designs were fabricated, and their operation properties were determined and compared. The optimized detector had the following electrode design: an electrode pitch of 1.2 mm, an electrode width of 0.8 mm and a spacing between the electrodes of 0.4 mm. gamma-ray energy spectra were measured for energies in the range of 60 - 660 keV. The low-energy tail in the spectrum was reduced significantly when the CZT strip detector was used.This work has been carried out under the nuclear R&D program of the Ministry of Education, Science and Technology (MEST) of Korea. This work was supported by a Korea Research Foundation Grant funded by the Korean Government (MOEHRD, Basic Research Promotion Fund) (KRF-2008-313-D01255)