Infrared detection and imaging have a wide range of applications in thermal imaging, optical communication, gas sensing, and night vision. Currently, detection in the short-wave infrared (SWIR, 1 – 3 um) predominantly utilizes semiconducting materials such as single-crystalline germanium (Ge) and III-V semiconductors such as indium gallium arsenide phosphide (InGaAsP). The epitaxial growth of these materials often entails sophisticated methods that require high process temperatures and careful lattice matching with the substrate, making device fabrication costly and often poorly scaled. Furthermore, the presence of toxic elements in semiconductor alloys used for infrared detectors – notably As, Pb, Cd, and Hg – has led to concerns on the sustainability of these devices and discouraged use in certain bioelectronic applications such as human skin detection
Recently, Tellurium (Te) has received considerable attention as a promising candidate for the next generation of SWIR photodetectors. Te’s band gap can be tuned from 0.31 eV in bulk form to 1.04 eV in monolayer form. The recent pioneering of deposition of a quasi-2D Te film via thermal evaporation has enabled the fabrication of fully scalable devices for transistor and optical sensing applications. However, the performance of uncooled Te photoconductors is limited by the high thermal noise-induced dark current due to the inherently small bandgap. In this project, our group will be exploring ways to fabricate highly scalable SWIR detectors based on large-area Tellurium film with creative approaches and device engineering that enable high performance at room temperature.
Project is currently funded by: Federal