Oxidation-Process Dependence of Single Photon Sources Embedded in 4H-SiC MOSFETs

Single photon sources (SPSs) in 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) were investigated using confocal microscope techniques. It was found that SPSs appeared only at 4H-SiC/SiO2 interface regions of wet-oxide C-face MOSFETs. The other regions of MOSFETs such as source, drain and well did not have SPSs. The luminescent intensity of the SPSs at room temperature was at least twice larger than that of nitrogen-vacancy center, in diamond. We examined four types of C-face and Si-face 4H-SiC MOSFETs with different oxidation processes, and as a result, it can be concluded that the formation of the SPSs strongly depended on the preparation conditions of SiC/SiO2 interfaces