Development of high-performance detector technology for UV and IR applications

Abstract

Ultraviolet (UV) and infrared (IR) detector and array technologies have proven to be at the heart of many remote sensing instruments for various NASA missions. These exciting AlGaN ultraviolet avalanche photodiode (UV-APD) and HgCdTe-graphene photodetector and focal plane array (FPA) technologies are being developed for high performance UV and IR sensing to support and further advance a variety of NASA Earth Science applications. This paper will present our recent results on GaN/AlGaN UV-APDs grown by metal-organic chemical vapor deposition (MOCVD) on GaN substrates with avalanche gains greater than 5×106, and high responsivities. We are also developing room temperature operating graphene-enhanced HgCdTe mid-wave infrared (MWIR) detectors and focal plane arrays (FPAs). These compact and low-cost MWIR sensors can benefit various NASA remote sensing applications. For MWIR detection it is very desirable to develop IR detector technologies that operate at or near room temperature to minimize cooling requirements. The 2-5 μm MWIR spectral band is useful for measuring sea surface temperatures, cloud properties, volcanic activities, and forest fires, among other applications. Using low size, weight, power, and cost MWIR sensors on smaller platforms in low orbit can enable improved measurements of thermal dynamics with high spatial resolution. We will discuss modelling and experimental results for these devices.