Abstract：The annealing was used to remove the adsorbed gases and impurities on graphene film, and the state of graphene surface was changed. The surface of graphene film before and after annealing was characterized in situ by atomic force microscope and Kelvin probe force microscope. The surface morphology and surface potential map of graphene film before and after annealing were obtained respectively. The work function was calculated according to the surface potential map, and the change mechanism of work function induced by annealing was analyzed. The results show that the annealing treatment causes the escape of water molecular between the graphene film and substrate, which reduces the gap between graphene film and SiO2 substrate and the P-type doping level of graphene film， resulting in the increasing of the Fermi level and the decreasing of work function.
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JIANG Yan, CHENG Zhenhua, SONG Juan. Effect of annealing on work function of CVD-grown graphene films[J]. Journal of Jiangsu University(Natural Science Eidtion)
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2024, Vol. 45 
