Simulation of near-infrared photodiode detectors based onβ-FeSi2/4H-SiC heterojunctions

摘要

In this paper,we propose a near-infrared p-type β-FeSi2-type 4H-SiC heterojunction photodetector with semiconducting silicide (β-FeSi2) as the active region for the first time.The optoelectronic characteristics of the photodetector are simulated using a commercial simulator at room temperature.The results show that the photodetector has a good rectifying character and a good response to near-infrared light.Interface states should be minimized to obtain a lower reverse leakage current.The response spectrum of the β-FeSi2/4H-SiC detector,which consists of a p-type/β-FeSi2 absorption layer with a doping concentration of 1 x 1015 cm-3 and a thickness of 2.5 μm,has a peak of 755 mA/W at 1.42 μm.The illumination of the SiC side obtains a higher responsivity than that of the β-FeSi2 side.The results illustrate that the/β-FeSi2/4H-SiC heterojunction can be used as a near-infrared photodetector compatible with near-infrared optically-activated SiC-based power switching devices.