Modeling and Design of a New Piezoelectronic Transistor for Ultralow-Voltage High-Speed Integrated Circuits

A new piezoelectronic transistor (PET) is proposed for ultralow-voltage high-speed integrated circuits. The device is comprised of a cylindrical piezoresistive (PR) channel and a torus-shaped piezoelectric (PE) gate surrounding the channel for applying pressure from the PE gate to the PR channel without any support structure. The PR channel can largely change its resistivity owing to the metal-insulator transition that is induced by the pressure applied from the PE gate. The PET can achieve high current drivability even at ultralow voltages (e.g., 0.2 V) due to the metallic channel during its ON-state and exhibit low leakage current due to the insulating channel during its OFF-state. In this study, two design methodologies of the PET are proposed to achieve a desired ON-current at an ultralow voltage or a desired OFF-current in the shutoff state. Both the designs can maintain an ON-current density that satisfies a value requested for achieving reliability. Also, we develop an equivalent circuit for analyzing the performance and behavior of the PETs and circuits configured with them. An inverter configured with complementary PETs can exhibit high-speed performance [several gigahertz (GHz) operations] at ultralow voltages (~0.2 V).