Spray pyrolysis of graphene oxide for field-effect transistor biosensor application

Field effect transistor (FET) with graphene oxide deposited on the channel for biosensor application is fabricated using p-type silicon on insulator (SOI) wafer. The graphene oxide (GO) is deposited by using an effective and low cost technique called spray pyrolysis mechanism on the silicon dioxide layer (i.e. after the silicon with 70 nm is etched). The physical surface topology is characterized using atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results show that the GO flake exist on the deposited area with thickness ranging from 3 nm to 8 nm. For electrical characterization, the device uses a back-gate to modulate the channel. Results show that the GO show better conductivity, stable response and less noise proving that it is suitable for biosensing applications.