Evidences of sensitization mechanism for PbSe thin films photoconductor

Over the past decades, sensitization has been considered as a key process that determined the performance of lead selenide (PbSe) photoconductive detectors. However, insufficiency of evidences about the changes on material properties and structure in micro level becomes a barrier on comprehensive explanation of the sensitization mechanism. In this work, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) technologies were employed to characterize the materials properties evolution process of PbSe during sensitization. Changes on microstructure was identified in details by high-resolution transmission electron microscope (HRTEM). Accordingly, we provided a profile of the sensitization mechanism in micro level. With these evidences, significant impacts on the photoconductive performances of PbSe could be well explained via the charge separation model.