Single-layer graphene layers have been synthesized by using chemical vapor deposition, subsequently transferred on 300 nm SiO₂/Si and quartz substrates, and doped with AuCl₃ by spin coating for various doping concentrations (nD) from 1 to 10 mM. Based on the nD-dependent variations of Raman frequencies/peak-intensity ratios, sheet resistance, work function, and Dirac point, measured by structural, optical, and electrical analysis techniques, the p-type nature of graphene is shown to be strengthened with increasing nD. Especially, as estimated from the drain current-gate voltage curves of graphene field effect transistors, the hole mobility is very little varied with increasing nD, in strong contrast with the nD-dependent large variation of electron mobility. These results suggest that AuCl₃ is one of the best p-type dopants for graphene and is promising for device applications of the doped graphene.

Keywords: 그래핀,AuCl₃,p형 도핑,도핑농도,디락점,이동도,면저항,일함수,투과도,Graphene,P doping,Doping concentration,Dirac point,Mobility,Sheet resistance,Work function,Transmittance