Dual band ultraviolet AlGaN photodetectors for space applications

Summary form only given. We report on the design, fabrication and testing of a back-illuminated, voltage bias selectable, dual band deep ultraviolet (UV) AlGaN photodetector for integration into space spectroscopic instrumentation. The photodetector can separate UV-A and UV-B band radiation by bias switching a two terminal n-p-n homojunction structure that is fabricated in the same pixel. When a forward bias is applied between the top and bottom electrodes, the detector can sense UV-A and reject UV-B band radiation. Alternatively, under reverse bias, the photodetector can sense UV-B and reject UV-A band radiation. The proof-of-concept design presented here shows that it is feasible to fabricate a dual-band deep UV photodetector based on the current state-of-art AlGaN material growth and fabrication technologies.