This Small Business Innovation Research (SBIR) project seeks to develop avalanche photodiode (APD) and its array, for solar-blind detection in UV wavelengths ranging from 200 nm to 250 nm for space applications. The solar-blind UV APD is based on III-nitride (III-N) technology. The ultra-wide bandgap (UWB) of AlXGa1-XN material system enables to achieve highly efficient, radiation-hard detectors capable of operating at high temperatures in the solar-blind UV regime without the need for external filters. The proposed solar-blind UV-APD will be capable to have high gain and low dark current (few pico amperes) so that the array of which can be used for solar blind imaging. In Phase I, we will perform material growth and characterization to achieve high quality AlGaN material system, verifying the material quality and performance in the solar blind ranges by making device. Design-simulation of APD device follows to optimize the structural parameters. In Phase II, the proposed solar-blind UV APD devices will be further optimized, fabricated, packaged as arrays and evaluated for high multiplication gain and low noise performance. We anticipate achieving a sufficiently high yield on large area substrates for economic production of large format for space applications as well as defense, and commercial bio-chemical systems applications.
UV spectroscopy and imaging instruments require UV detection capabilities. UV emission lines and bands from H, C, O, N, S, OH and CO; UV absorption lines by CO2, H2O, NH3, N2; and UV surface reflectance spectra are essential for detection ice, iron oxides, organics, and other compounds on planetary bodies. Future NASA missions include: New Horizons (NH) mission to Pluto, and Lyman Alpha Mapping Project (LAMP) instrument on Lunar Reconnaissance Orbiter (LRO) mission. NASA mission of relevance is the Large UV Optical Infrared Surveyor (LUVOIR).
Commercial and defense applications includes detection of bio-chemical species and explosives in a form of detection system that is compact, portable identification systems for warfighters and first responders. Defense also includes early missile threat warning and free-space communications. Commercial applications include industrial, lab instrument, and consumer UV monitoring.