Optimum Bandgap and Supply Voltage in Tunnel FETs

• Published in: IEEE transactions on electron devices Vol. 61; no. 8; pp. 2719 - 2724
• Main Authors: Qin Zhang, Yeqing Lu, Richter, Curt A., Jena, Debdeep, Seabaugh, Alan
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.08.2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Analytic model; Analytical models; Computer simulation; Effective mass; Electric potential; Field effect transistors; Gates; graphene nanoribbon (GNR); Logic gates; Mathematical analysis; Mathematical models; Nanostructure; nanowire (NW); Photonic band gap; Semiconductors; Transistors; tunnel field-effect transistor (TFET); Tunneling; tunnel field-effect transistor (TFET); Analytic model; graphene nanoribbon (GNR); nanowire (NW)
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2014.2330805

A physics-based analytic model of the ON- and OFF-currents in a homojunction tunnel field-effect transistor (TFET) is used to understand the relationship between bandgap, gate length, ON-current, OFF-current, ON/OFF current ratio, and supply voltage to meet minimum energy requirements. The model, which applies to direct-bandgap semiconductors, is validated against numerical simulations to show that it captures the trends of more comprehensive simulations. The analytic model is then used to compare alternative channel materials for TFETs. Gate-all-around InAs nanowire and graphene nanoribbon TFETs are used as design examples at gate lengths of 10 and 15 nm and for an ON/OFF current specification of 10 5 . The results suggest that TFETs based on 2-D materials can be more energy efficient than semiconductor nanowire TFETs and conventional metal-oxide-semiconductor field-effect transistors for low-power logic.