The enhancement of Hall mobility and conductivity of CVD graphene through radical doping and vacuum annealing

We report an innovative method for chlorine doping of graphene utilizing an inductively coupled plasma system. TEM analysis reveals that the pre-doping (doping before wet transfer) and normal-doping (doping after wet transfer) were generally formed and trapped well between graphene layers; moreover, by thermal stability testing, the chlorine-trapped layer-by-layer graphene showed a very high thermal stability in vacuum at 230 °C for 100 hours. We also obtained the sheet resistance and optical transmittance of the Cl-trapped tri-layer graphene at 72 Ω sq⁻¹ and 95.64% at 550 nm wavelength, respectively. In addition, the high hole mobilities for the chlorine-trapped bi- and tri-layer graphene were observed up to 3352 and 3970 cm² V⁻¹ s⁻¹, respectively.