Developing better contacts on Si is one of the main challenges for Si-based device technology. The present work reports the fabrication and detailed electrical properties of graphene/n-type Si Schottky diodes. The graphene/n-type Si Schottky diode without H2O2 treatment shows a poor rectifying behavior with an ideality factor (eta) of 3.5 and high leakage eta > 2 implies that the interfacial defects influence the electronic conduction through the device. However, the graphene/n-type Si Schottky diode with H2O2 treatment shows a good rectifying behavior with eta of 1.9 and low leakage. Such an improvement indicates that a good passivation is formed at the interface as a result of the reduction of the defect density. These experimental demonstrations suggest that it may be possible to minimize the adverse effects of the interface states to obtain functional devices using H2O2 treatment. (C) 2013 Elsevier B.V. All rights reserved.