Photoelectronic properties of HgI2 crystals for nuclear radiation detection

Photoelectronic properties of red mercuric iodide single crystals, grown from its saturated solution in tetrahydrofuran, have been studied for the wavelength range 450–700 nm at temperatures 80,110, 175, 235 and 300 K. Various aspects of the optical generation of charge carriers have been discussed. The computer simulation of the room temperature photoconductivity has generated the optimized values of the mobility-lifetime products μeτe = 5.67 × 10−5 cm2/V, μhτh = 0.18 × 10−5 cm2/V), and surface recombination velocities (Se = 3.2 × 105 cm/s, Sh = 4.5 × 105 cm/s) of the charge carriers in these crystals. The estimated values of the electron and hole drift lengths for typical electric fields suggest that, under the negative electrode illumination, THF α-HgI2 crystals have high potential as regards to their use as photodetectors in most of the scintillation spectrometers.