Variation of the resistivity and chemical composition of CVD graphene under annealing in a reductive atmosphere

18th Russian Youth Conference on Physics of Semiconductors and Nanostructures, Opto- and Nanoelectronics

Tolochko, O.V.^1 ; Larionova, T.V.^1 ; Koltsova, T.S.^1 ; Kozlova, M.V.^1 ; Bobrynina, E.V.^1 ; Martynova, O.A.^1 ; Gasumyants, V.E.^1

Peter the Great St. Petersburg Polytechnic University, 29 Polytechnicheskaya str., St. Petersburg

195251, Russia^1

关键词: Chemical compositions;    Comparative analysis;    Observations and measurements;    Reductive atmospheres;    Resistance measurement;    Resistance temperature;    Resistivity dependence;    Standard technology;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/816/1/012012/pdf
DOI  :  10.1088/1742-6596/816/1/012012

来源: IOP

【 摘 要 】

Graphene samples synthesized by chemical vapor deposition, transferred onto Si/SiO2substrates by the standard technology using PMMA, and then annealed in a reductive atmosphere have been characterized by XPS observations and measurements of the resistance temperature dependence. It was shown, that most of as-transferred samples exhibit a metallic-like resistivity dependence but some of them can demonstrate a non-metallic one. A comparative analysis of the results obtained by the XPS study and resistance measurements allowed us to conclude that the conduction process in CVD graphene is directly affected by functional groups adsorbed on the sample surface. Annealing in a mixture of H2and Ar at T = 250-750°C is shown to result in a cleaning of the graphene surface from adsorbed contaminations and in a modification of the resistance temperature dependence which demonstrates a higher slope in case of a metallic-like behavior for as-transferred samples and a suppression of the activation-type dependence in case of a non-metallic one.