▎ 摘 要
The temperature-dependent current-voltage (I-V) characteristics of graphene/n-type Si Schottky diodes with and without sulfide treatment were measured in the temperature range of 150-420 K. The temperature dependence of forward-bias I-V characteristics can be explained on the basis of the thermionic emission theory by assuming the presence of Gaussian distribution of the barrier heights. The graphene/n-type Si device with sulfide treatment exhibits a good rectifying behavior with the ideality factor of 1.8 and low leakage at 300 K. The enhanced device performance is considered to mainly come from the presence of Si-S bonds that serve to improve the Schottky barrier inhomogeneity. Compared to the fitting data for the temperature-dependent reverse-bias I-V characteristics of graphene/n-type Si devices without sulfide treatment, the fitting data for the temperature-dependent reverse-bias I-V characteristics of graphene/n-type Si devices with sulfide treatment show that a higher barrier height for hopping result in a lower leakage current. This is because of more homogenous barrier height for graphene/n-type Si devices with sulfide treatment.