Lead Chalcogenide Mid-Wave Infrared High Detectivity Detectors

The US Army is seeking medium wavelength infrared detectors (MWIR) that can use spectral signatures in 2.0-4.5 µm range to remotely detect and characterize chemical/biological agents and stimulants. Group III-V and II-VI semiconductor-based focal plane arrays (FPAs) have the desired properties for the MWIR for species detection. However they require cryogenic cooling to minimize dark current noise, which adds significantly to the size, weight, power and cost of the detector.Lead chalcogenide-based MWIR detectors can operate at temperatures exceeding 200 K. However, the performance of lead chalcogenide-based devices is significantly below theoretical limits. These also exhibit significant response non-linearity as a function of radiant power. The technology we propose has significant benefits as it leads to the fabrication of low-cost room-temperature MWIR detectors. These have a wide range of applications in industrial, environmental, and medical sectors. MWIR detectors are being used extensively in a broad range of industries including: The Internet of Things (IoT), Manufacturing Process Control, Automotive, Medical Applications, and Homeland Security. As for medical application, various medical tools such as blood vein monitor, brain trauma detection, diabetic neuropathy, thermography, and cancer cell detection are invented using IR technology due to the non-contact and non-destructive monitoring. As for automotive industry, uncooled IR detectors are the critical component of LiDARs. These will increase driving safety and will accelerate development of autonomous vehicles.