LAUSR

The direct growth of graphene affording wafer‐scale uniformity on insulators is paramount to electronic and optoelectronic applications; however, it remains a challenge to date, because it entails an entirely different growth mode than that over metals. Herein, the metal‐catalyst‐free growth of quasi‐suspended graphene on a Si wafer is demonstrated using an interface‐decoupling chemical vapor deposition strategy. The employment of lower‐than‐conventional H2 dosage and concurrent introduction of methanol during growth can effectively weaken the interaction between the synthesized graphene and the underlying substrate. The growth mode can be thus fine‐tuned, producing a predominantly monolayer graphene film with wafer‐level homogeneity. Graphene thus grown on a 4 inch Si wafer enables the transfer‐free fabrication of high‐performance graphene‐based field‐effect transistor arrays that exhibit almost no shift in the charge neutral point, indicating a quasi‐suspended feature of the graphene. Moreover, a carrier mobility up to 15 000 cm2 V‐1 s‐1 can be attained. This study is anticipated to offer meaningful insights into the synthesis of wafer‐scale high‐quality graphene on dielectrics for practical graphene devices.