Realization, Calibrations and Spatialization of ß-(Al)Ga2O3 UVC Photodetectors of Extreme Solar Blindness for Space Observations
Résumé
There is a surge in interest for the ultra-wide bandgap (Eg ~ 4.9 eV) semiconductor gallium oxide (Ga2O3). A key driver for this boom is that single crystal wide area bulk β-Ga2O3 substrates have become commercially available and that a variety of methods have been shown to give high quality epitaxial growth. Amongst a whole range of potential applications (power/switching electronics, solar transparent electrodes, etc.) extreme solar blindness photodetectors in β-Ga2O3, the more stable monoclinic phase of Ga2O3, offer the most exciting perspectives for deep ultraviolet observations of the Herzberg continuum (200-242 nm) in Space. We present an overview of the complete realization process (epitaxy, photolithography, singulation and packaging), performances evaluation and spatialization of a series of β-(Al)Ga2O3 photodetectors developed (slight Al alloying to enhance ultraviolet response below 253 nm), space qualified and selected for flight on the INSPIRE-SAT 7 nanosatellite (launch planned in early 2023).