Metal-Free Catalytic Preparation of Graphene Films on a Silicon Surface Using CO as a Carbon Source in Chemical Vapor Deposition

The metal-free synthesis of graphene films on Si substrates, the most common commercial semiconductors, is of paramount significance for graphene application on semiconductors and in the field of electronics. However, since current research mainly uses C-H gas as the carbon source in chemical vapor deposition (CVD), and Si does not have a catalytic effect on the decomposition and adsorption of C-H gas, it is challenging to prepare high-quality graphene on the Si surface directly. In this work, we report the growth of graphene directly on Si without metal catalysis by CVD using CO was selected as the carbon source. By controlling the growth temperature (1000–1150 °C), a process of 2–5 layers of graphene growth on silicon was developed. The electrical performance results showed that the graphene film had a sheet resistance of 79 Ω/sq, a resistivity of 7.06 × 10−7 Ω·m, and a carrier migration rate of up to 1473.1 cm2 V−1·S−1. This work would be a significant step toward the growth of graphene on silicon substrates with CO as the carbon source.