Improved inter-device variability in graphene liquid gate sensors by laser treatment

Abstract

We investigate the influence of a visible laser treatment on the electrical performance of CVD-grown graphene-based liquid gate sensors. This method allows to treat locally the graphene sheet, improving the electrical characteristic for biochemical sensing applications. Optimizing the laser exposure, the Dirac point (minimum conductivity voltage) was shifted around 300 mV to lower voltages, together with a decrease of the inter-device electrical variability. These results open the door to use the laser treatment to increase the sensibility and reproducibility of liquid gate graphene-based devices as sensors or biosensors.