Subthreshold Schottky-contacted carbon nanotube network film field-effect transistors for ultralow-power electronic applications

Abstract

Abstract Ultralow-power electronics is critical to wearable, portable, and implantable applications where the systems could only have access to very limited electrical power supply or even be self-powered. Here, we report on a type of Schottky barrier (SB) contacted single-walled carbon nanotube (SWCNT) network film field-effect-transistors (FETs) that are operated in the subthreshold region to achieve ultralow-power applications. The thin high-k gate dielectric and the overlap between the gate and the source electrodes offer highly efficient gate electrostatic control over the SWCNT channel and the SB at the source contact, resulting in steep subthreshold switching characteristics with a small subthreshold swing (∼67 mV dec−1), a large current on/off ratio (∼106), and a low off-state current (∼0.5 pA). A p-channel metal-oxide-semiconductor inverter built with the subthreshold SB-SWCNT-FETs exhibits a well-defined logic functionality and small-signal amplification capability under a low supply voltage (∼0.5 V) and an ultralow power (∼0.05 pW μm−1). The low-voltage and deep subthreshold operations reported here could lay an essential foundation for high-performance and ultralow-power SWCNTs-based electronics.