4H-SiC UV photo detectors with large area and very high specific detectivity

Pt/4H-SiC Schottky photodiodes have been fabricated with the device areas up to 1 cm². The I-V characteristics and photoresponse spectra have been measured and analyzed. For a 5 mm×5 mm area device leakage current lower than 10^-15 A at zero bias and 1.2×10^-14 A at -1 V have been established. The quantum efficiency is over 30% from 240 to 320 nm. The specific detectivity, D^*, has been calculated from the directly measured leakage current and quantum efficiency are shown to be higher than 10¹⁵ cmHz¹2//W from 210 to 350 nm with a peak D^* of 3.6×10¹⁵ cmHz¹2//W at 300 nm.