AlGaN photodetectors for applications in the extreme ultraviolet (EUV) wavelength range

We report on the fabrication of Schottky-diode-based Extreme UltraViolet (EUV) photodetectors. The devices were processed on Gallium Nitride (GaN) layers epitaxially grown on 4 inch Silicon (111) substrates by Metal-Organic Chemical Vapor Deposition (MOCVD). Cutoff wavelength was determined together with the spectral responsivity measurements in the Near UltraViolet (NUV) range (200nm to 400nm). Absolute spectral responsivity measurements were performed in the EUV range (5nm to 20nm) with the synchrotron radiation using the facilities of Physikalisch- Technische Bundesanstalt (PTB), located at Berliner Elektronenspeicherring-Gesellschaft fuer Synchrotronstrahlung (BESSY). The described work is done in the framework of the Blind to Optical Light Detectors (BOLD) project supported by the European Space Agency (ESA).