Reconfigurable Electric Double Layer Doping in an MoS₂ Nanoribbon Transistor

A back-gated multilayer nanoribbon molybdenum disulfide (MoS₂) transistor grown by chemical vapor transport and doped using polyethylene oxide cesium perchlorate is fabricated and characterized. Ions in the polymer dielectric are directed by side gates to the source and drain access regions where they form electric double layers (EDLs) that control the carrier densities. This allows the junctions of the same transistor channel to be reconfigured as an n-MOSFET, p-MOSFET, and as a tunnel field-effect transistors. The EDLs are formed at room temperature and then locked into place by cooling the polymer below the glass transition temperature (240 K). Transport measurements are presented and explained using simulated band diagrams. Both n and p-conduction in MoS₂ is demonstrated using solid polymer ion doping, enabling characterization of a semiconductor in which the doping of the same channel has been reconfigured to form three different transistor configurations.