Highly Stable Chemical N-doping of Graphene Nanomesh FET

N-type doping of graphene with long-term air stability represents a significant challenge for practical application of graphene electronics. This paper reports a reversible doping method that uses SU-8 photoresist as a doping and encapsulating material to enable highly air-stable n-type semiconducting properties of graphene. The SU-8 resist simultaneously serves as an effective electron dopant, a dielectric medium, and an excellent encapsulating layer. The air-stable n-type characteristics of the as-doped graphene were verified by Raman spectra and transport properties. The SU-8 doping has minimum damage to the hexagonal lattice of graphene and can be reversed by removing the uncrosslinked SU-8 resist.