InAs Nanocrystal-based Infrared Imager Operating beyond Telecom Wavelengths
Résumé
Colloidal III-V nanocrystals offer a promising route toward low-cost, CMOS-compatible infrared imaging beyond the silicon band gap. Here, we demonstrate a short-wave infrared (SWIR) imager operating at telecom wavelengths based on InAs nanocrystal photoconductors. InAs nanocrystals, with a spectral cut-off extending to 1600 nm, are synthesized and ligand-exchanged, to induce n-type conductive ink. Combination of photoemission, optical spectroscopy and transport measurements enable a full determination of the electronic structure in the vicinity of the Fermi level: where the Fermi level is quasi-degenerate with the conduction band and trap densities is limited. Guided by these electronic characteristics, we fabricate infrared sensitized focal plane arrays using a single-step deposition process. The resulting imager enables room-temperature, real-time video imaging at telecom wavelengths under ambient operation, demonstrating the potential of III-V nanocrystal films for scalable infrared imaging technologies.