SiCGe/SiC heterojunction and its MEDICI simulation of optoelectronic characteristics

Optoelectronic characteristics of the SiC_1-xGe_x /SiC heterojunction photodiode are simulated using MEDICI after the theoretical investigation of key properties for SiC_1-xGe_x. The calculations show that SiC_1-xGe_x /SiC with x=0.3 may have a small lattice mismatch with 3C-SiC and a good response to the visible light and near infrared light. The response spectrum of the SiC_1-xGe_x /SiC heterojunction photodiodes, which consists of a p-type SiC_1-xGe_x absorption layer with a doping concentration of 1\times10^15cm－3, a thickness of 1.6μm and x=0.3, has a peak value of 250mA/W at 0.52μm and the peak value can even reach 102 mA/W at 0.7μm.