Graphene field-effect transistors (GFETs) were fabricated by aligning the dispersed graphene flakes precisely with the pre-defined Ti/Au electrodes on SiO2/Si substrate by using a non-uniform electric field, where a large density of the graphene flakes was prepared by sonicating three-dimensional (3-D) graphene foam. Effects of ultra-violet (UV) illuminations and vacuum annealing on the electrical characteristics of the processed GFETs were investigated.Aremarkable increase in conductivity and carrier mobilitywas observed after vacuum annealing at 100°C, which was more effective than UV illuminations to improve the electrical performance of our GFETs. Our method to obtain the dispersed graphene flakes from 3-D graphene foam and assemble them by a dielectrophoretic force allows a reliable, scalable, and controllable fabrication of GFETs.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering