Selection of CdTe detectors for the detection plane of the ECLAIRs gamma-ray burst detector

Schottky In/CdTe/Pt detectors (4×4 mm2, 1 mm thickness, produced by ACRORAD Japan) have been chosen to set up the detection plane of the ECLAIRs gamma-ray burst (GRB) detector to fly aboard the French–Chinese mission SVOM in late 2013. The instrument will detect GRBs from 4 up to 250 keV. Two hundred elementary detection modules, named XRDPIX, are used to build the detector. They are based upon an innovative hybridization of a low noise front-end electronics chip with 32 CdTe detectors. In order to reduce the noise and reach the 4 keV threshold, the detectors for the flight model are carefully selected. They present the best performance in terms of leakage current and energy resolution. We report on these tests and the selection criteria elaborated from the study of a first set of 500 detectors.