Comparison of 5 and 10 mm thick HgI2 pixelated γ-ray spectrometers

HgI2 detectors fabricated with pixelated anodes were tested as potential room temperature spectrometers. Spectra were obtained with 5 and 10 mm thick devices, and their results were compared. The 5 mm thick devices showed some effect of the anode weighting potential, while the 10 mm thick devices showed the effects of charge diffusion/sharing and electron trapping. A resolution near 1.4% FWHM using a 137Cs source was achieved after correcting for the interaction depth within the detector. The resolution from individual depths was as low as approximately 1.1% FWHM.