▎ 摘　　要

Using the discharge current analysis method, the contribution of charge generation through an interfacial reaction at a graphene /substrate interface is assessed to be on the order of 10(14)/cm(2), which is similar to 20% of the total charging sites. The validity of this method, which separately extracts the density of the charging sites related to the initial defect density of the graphene from the contribution of interfacial reactions is examined by measuring the discharge current of graphene field-effect-transistors at different ambient and temperatures. This method will be crucially instrumental in finding an optimal substrate material for graphene devices. (C) 2014 AIP Publishing LLC.