Authors: Hao Yang*, Ting Mei, Lei Chen, Xiaojiang Li, and Jianbang Zheng
The lead selenide (PbSe) films were fabricated using vapor phase deposition (VPD) method. The as-deposited films were sensitized in iodine and oxygen hybrid atmosphere, then in pure oxygen. The photoelectrical properties and crystalline structure were characterized for samples sensitized with and without iodine. The responsivity of 4 A/W was gained at the optimal iodine dose in the sensitization process. It is revealed that the photoelectric performance can be further enhanced with iodine at low iodine molecular density of <1.5×1012 mm-3 compared with that of only oxygen used. The responsivity is correlated with the deviation of stoichiometry of PbSe microcrystal. These results should be helpful to understand the roles of iodine and oxygen in the sensitization process of lead salt photoconductors.
Keywords: polycrystalline PbSe; iodine dose; sensitization; photoelectric performance