Crystallite Size Effect on X-ray-instigated Photocurrent Properties of PbWO4 Thick Film.

X-rays are widely used in many domains such as clinical diagnostic, imaging, industrial inspection, and environmental safety, allowing researchers for innoviative superior low-dose sensor development. In direct detection type of X-ray, X-ray photons are directly absorbed by photoconductors such as HgI₂, PbI₂, and BiI₃ that are the available X-ray semiconductor detectors. This study analyzes the properties of micro and nanocrystalline PbWO₄ prepared as thick film above the interdigitated electrode for direct photon detection. PbWO₄ was found to have a better attenuation value of ~ 6.13 cm²/g at 70 keV as compared with the existing semiconductor detectors. The X-ray-instigated photocurrent behavior of PbWO₄ was measured at various low doses by an intra-oral 70 keV machine connected with a Keithley model 2450 measuring source meter. Maximum sensitivity was found to be about 0.40 and 9.80 nC/mGycm³, respectively, for micro and nanocrystalline PbWO₄, obtained at 7.97 mGy dose. The nanocrystalline PbWO₄ thick film displayed more than twenty-four times sensitivity as compared with the microcrystalline PbWO₄ film by virtue of the nanocrystalline size effect on X-ray detection. [ABSTRACT FROM AUTHOR]