Silicene transistors— A review

Free standing silicene is a two-dimensional silicon monolayer with a buckled honeycomb lattice and a Dirac band structure. Ever since its first successful synthesis in the laboratory, silicene has been considered as an option for post-silicon electronics, as an alternative to graphene and other two-dimensional materials. Despite its theoretical high carrier mobility, the zero band gap characteristic makes pure silicene impossible to use directly as a field effect transistor (FET) operating at room temperature. Here, we first review the theoretical approaches to open a band gap in silicene without diminishing its excellent electronic properties and the corresponding simulations of silicene transistors based on an opened band gap. An all-metallic silicene FET without an opened band gap is also introduced. The two chief obstacles for realization of a silicene transistor are silicene's strong interaction with a metal template and its instability in air. In the final part, we briefly describe a recent experimental advance in fabrication of a proof-of-concept silicene device with Dirac ambipolar charge transport resembling a graphene FET, fabricated via a growth-transfer technique. (topical review)