Study on SiC UV/EUV Coaxial Photodetector

Abstract

In this paper, a novel 4H-SiC coaxial p-i-n ultraviolet photodetector with intense photon absorption and high quantum efficiency is studied. The spectral response and electric field distribution of the detector are calculated by TCAD software. The results showed that the innovative 4H-SiC ultraviolet coaxial p-i-n photodetector has a spectral response peak of 0.1998 A/W at 260 nm illumination wavelength and has more than twice response higher than the traditional 4H-SiC p-i-n photodetector, when the illumination wavelength is under 270 nm. The quantum efficiency of the coaxial photodetector reaches 95.3%. Moreover, in the wavelength range of EUV, the 4H-SiC ultraviolet coaxial photodetector shows a relatively high response, while the response is barely observed for the traditional 4H-SiC p-i-n photodetector. For the large area coaxial p-i-n photodetector, the problem of laterally undepleted i layer can be solved by multiple P+-type implanation. The new structure significantly enhances the rate of incident light absorption, prevents the light absorption of the conventional metal electrode and P+ layer, and provides an innovative approach for the construction of ultraviolet photodetectors in the future.