TUNABLE PHOTODETECTORS BASED ON AMORPHOUS SI/SIC HETEROSTRUCTURES

We describe a novel family of two-color photodetectors based on pinip heterostructures in hydrogenated amorphous Si/SiC. The devices operate as bias-controlled tight detectors with enhanced absorption in either the blue or the red regions. Compared to other two-color sensors based on amorphous Si/SiC nipin structures, they exhibit sharper wavelength selection and higher rejection ratios with excellent quantum efficiencies: full width at half maximum (FWHM) less than 130 nm, suppression up to 27 dB, and peak responsivity of about 150 mA/W are reported for both the blue and the red window. Simulation of the photoresponse of the device under steady-state and time-dependent voltage bias and under continuous illumination is also presented.