▎ 摘　　要

Graphene platelets synthesized by chemical exfoliation were deposited to form a film on Cu substrate. Samples of the film of graphene platelets were subjected to laser irradiation with wavelength 266 nm, pulse duration 6 ns from Nd-YAG laser at repetition of 10Hz. Microwave hydrogen plasma treatment was also used for 300 s and 600 s to modify the film of graphene platelets on another set of samples. Raman spectroscopy on the film before and after these different treatments indicated that the crystallite size is reduced and defect density is increased. The samples coated with Au film and pressed with In film on the surface were used to determine the transient thermo reflectance from the surface upon incidence of Nd-YAG laser beam with wavelength 532 nm. Numerical analysis of the variation of thermo reflectance signal with time was used to evaluate the laser or plasma induced changes in the thermal conductivity of graphene film and the interface thermal conductance between Au and graphene. The results showed that the thermal conductivity of graphene platelet film is reduced although the interface thermal conductance is improved. The reduction in thermal conductivity of graphene platelets is explained by the decrease in the crystallite size and increase in defect density. The increase in the interface thermal conductance is also explained to arise from smoothening of the graphene platelet film surface and improvement in the contact between Au and graphene and graphene and Cu induced by laser or microwave plasma irradiation. (C) 2013 American Vacuum Society.