▎ 摘　　要

Films of graphene/copper composite in copper matrix were deposited on copper foil using an aqueous electrolyte solution of 0.2 M CuSO4 containing graphene oxide suspension at a low current density of 1.75 mA cm(-2). Graphene oxide is reduced by further heating the samples in flowing hydrogen atmosphere maintained at 20 Torr and 400 degrees C for 3 h. The composite samples with different thickness, between 365 and 515 mu m, deposited on a Cu foil of thickness 135 mu m were characterized for graphene structure, morphology, and distribution. Electrical resistivity and temperature coefficient of electrical resistance of the samples at 300 K were measured using a four-probe method. The results were used to determine the electrical resistivity and temperature coefficient of resistance of the composite layers. The volume fraction and resistivity of graphene were evaluated using effective mean field analysis of the resistivity and temperature coefficient of resistance of the composite films. The results illustrate that the resistivity of graphene is much lower than that of copper and copper-graphene composite films are favorable for electrofriction applications. (C) 2012 American Vacuum Society. [http://dx.doi.org/10.1116/1.3701701]