Graphene/4H-SiC Schottky photodetector operating in the visible spectrum range

¹ Mediterranea University of Reggio Calabria, DIIES Dept., 89124 Reggio Calabria, Italy
² National Research Council (CNR), ISASI Institute, 80131 Naples, Italy
³ University of Naples Federico II, DIETI Dept., 80125 Naples, Italy

^* Corresponding author: elisa.mallemace@unirc.it

Published online: 18 October 2023

Abstract

In this work, we present the first experimental results on a Schottky photodetector based on Silicon Carbide (SiC) and Graphene (Gr) designed to operate in the visible spectral range. While SiC has been extensively investigated for various applications in the ultraviolet domain, there are only a few works in the visible range, where SiC exhibits negligible optical absorption. To overcome such intrinsic limit of SiC, we exploit the properties of a single layer of Gr to enhance, significantly, the photodetection performance of the device operating, in our experiments, at the wavelength of λ=633 nm. From the current-voltage (I-V) characteristics, a series resistance of 3.7 kΩ, an ideality factor of 8.4, and the zero-bias Schottky barrier height of 0.755 eV have been calculated. Finally, the internal responsivity, as function of the reverse bias applied to the device, has been measured demonstrating a maximum value exceeding 1 mA/W at -5V.