Recent achievements of the high resolution Schottky CdTe diode for gamma-ray detectors

We describe the recent progress on the use of Schottky CdTe diode detectors for gamma-ray spectroscopy. The extremely low leakage current of the newly developed CdTe diode allows us to apply a much higher bias voltage in comparison with the previous CdTe detectors. Both the improved charge-collection efficiency and the low leakage current lead to a good energy resolution even at room temperature. Largearea CdTe diode detectors with dimensions of 21.5 × 21.5 mm are now available. By stacking 40 layers of these large-area devices, we have achieved a good energy resolution of several keV (FWHM) for MeV gamma-rays.