Ti:Sapphire laser irradiation of graphene oxide film in order to tune its structural, chemical and electrical properties: Patterning and characterizations

Abstract

Femtosecond laser processing was employed in order to tune various properties of graphene oxide (GO) films. Raman spectroscopy showed the effects of laser irradiation on decreasing the defects in the GO films. Structural and chemical properties of the irradiated GO films were investigated by XRD and XPS as a function of laser fluences. Conductive patterns were produced on insulating surfaces of GO films as a result of the removal of oxygen functional groups. Laser fluences dependent sheet resistances and current-voltage measurements were studied using four probe method. Investigation of the correlation between property changes in the GO films and the laser fluences used for irradiating the films can be useful for many applications, such as microelectronics, which requires control of various characteristics of the films. In addition to tuning various properties of the GO films, AFM and SEM studies were performed on different regions of the irradiated GO films, including films on silicon and gold electrodes, which showed regular ripples on gold electrodes. These investigations were also followed by optical contrast calculations of the films that can be used to recognize different regions of the films.