Wafer-Scale High-Detectivity Near-Infrared PbS Detectors Fabricated from Vapor Phase Deposition

The commercialization of uncooled lead-salt photoconductive (PbX PC) detectors has been restricted by the low-yield of standard chemical bath deposition (CBD) manufacturing technology. As an iterative solution, herein, a novel vapor phase deposition (VPD) route is demonstrated by fabricating the 3 in. wafer-scale uniform PbS sensitized films with high detectivity. The morphological evolution suggests that the self-assembled rod-like microstructure, which is dominated by the I2/PbS flux ratio in the VPD process, is the key to triggering the near-infrared (NIR, 1–3 μm) response of the PbS-sensitized films. The maximum peak detectivity of VPD-PbS NIR detector of 1.9 × 1011 cm Hz1/2 W–1 is achieved after optimizing the sensitization-condition dependence of PbS detector's performance. The high performance of wafer-scale VPD-PbS PC detectors, which attains the same performance as standard CBD-PbS detectors, manifests that the VPD technology opens up a new avenue to the industrialization of uncooled lead-salt PC detectors.