Oxygen-Aided Synthesis of Polycrystalline Graphene on Silicon Dioxide Substrates

We report the metal-catalyst-free synthesis of high-quality polycrystalline graphene on dielectric substrates [silicon dioxide (SiO2) or quartz] using an oxygen-aided chemical vapor deposition (CVD) process. The growth was carried out using a CVD system at atmospheric. pressure. After high-temperature activation of the growth substrates in air, high quality polycrystalline graphene is subsequently grown on SiO2 by utilizing the oxygen-based nucleation sites. The growth mechanism is analogous to that of growth for single-walled carbon nanotubes. Graphene-modified SiO2 substrates can be directly used in transparent conducting films and field-effect devices. The carrier mobilities are about 531 cm(2) V-1 s(-1) in air and 472 cm(2) V-1 s(-1) in N-2, which are dose to that of metal-catalyzed polycrystalline graphene. The method avoids the need for either a metal catalyst or a complicated and skilled postgrowth transfer process and is compatible with current silicon processing techniques.