Characteristics of PbI/sub 2/ crystal for use as a gamma-ray detector

We have been studying a /spl gamma/-ray detector which uses a lead iodide PbI/sub 2/ crystal. The detector fabricated from a PbI/sub 2/ crystal grown by 10-pass zone travelling molten zone (TMZ) method. The /spl mu//spl tau/product of this crystal are estimated to be about 1/spl times/10/sup -6/ cm/sup 2//V for electrons and about 6/spl times/10/sup -7/ cm/sup 2//V for holes. The resistivity of the PbI/sub 2/ crystal is estimated to be about 10/sup 12/ /spl Omega/cm. FWHM energy resolution of the detector for a photoelectric peak for the 59.5 keV /spl gamma/-rays is found to be about 5 keV.