Current developments in the recently introduced method of HgI2 crystal platelet growth by polymer assisted vapor transport are described. Crystal parameters are evaluated by making electrical measurements on x-ray detectors fabricated from HgI2 platelets, Selection for detector fabrication is on the basis of size and apparent crystalline perfection. Detectors have been fabricated with active areas averaging 2 to 3 mm2 and thicknesses ranging from 20 to 400 µm. Values of electron mobility and mobility-lifetime product measured for HgI2 platelet material are among the highest ever observed for HgI2.
The combination of low leakage current and good electron transport makes HgI2 platelets suitable for room-temperature x-ray spectrometry. An energy resolution of 370 eV (FWHM) for the 5.9 KeV Mn Kα line has been obtained, and representative low-energy x-ray fluorescence spectra are presented.