Photoconductive properties of chemically deposited PbS with dielectric overcoatings

Publisher Website
Google Scholar
Abstract
Overcoatings of Al2O3, As2S3, CdTe, MgF2, SiO, and SiO2 were vacuum deposited on thin‐film PbS photodetectors. Overcoating thicknesses were approximately those required to optimize antireflection properties. None of the overcoatings seriously degraded detector properties, although production yields were low with Al2O3, MgF2, and CdTe. The low yields are apparently due to physical incompatibilities of the overcoating and PbS film. Improved detector properties were obtained with As2S3 through a reduction of 1/f noise and passivation to hostile environments. The 1/f noise component is assessed by a comparison of the changes in detector performance parameters upon ’’flashing’’ with the changes theoretically expected for G‐R noise‐dominated detector.