Optoelectronic characteristics simulation and analysis of p-n Si/6H-SiC heterojunction

Applications of SiC in optoelectronics are restricted in the range from visible to near-infrared due to its wide bandgap. However, it may come true via Si/SiC heterojunction structure. In this paper, the effects of doping concentration, Si layer thickness, temperature and minority carrier lifetime on optoelectronic characteristics of the heterojunction are simulated. The results indicate that high doping concentration in SiC substrate and low doping concentration in Si layer can produce larger optoelectric response. But the doping concentration in Si layer can be increased appropriately so as to raise its operation temperature. When the minority carrier lifetime in Si layer is longer than 1ns, the optoelectric response is nearly not changed. It means that duration time of the optical pulse response of the heterojunction can be shortened via decreasing minority carrier lifetime in Si layer with constant optoelectric response.