Contents I. Introduction
Per the International Technology Roadmap for Semiconductors (ITRS) [2], there continues to be a movement toward “energy efficient sensing and computing and real-time communications”, which will address the global need to “create computer chips that are 100 times faster yet consume less power” as we embark upon the Internet of Things (IoT) [1]–[2]. With the rapid growth of ultra-low power devices needed for biomedical, military, and space applications, the challenge for the semiconductor industry and researchers continues to be the identification of different designs and structures to overcome the limitations of conventional MOSFET technology. The usage of MOSFETs can be limited by the short channel effect, drift velocity, accumulation of minority carriers and exponential increase of leakage current [3]–[4]. These limitations are grand challenges for the semiconductor industry as technology features are being miniaturized to the nano scale, particularly for the bioelectronics arena. Carbon nanotubes (CNTs) have outstanding potential for a wide range of applications due to small size, high mobility, high thermal stability and high current carrying density. These attributes make the carbon nanotube field-effect transistor (CNTFET) a promising candidate to overcome certain limitations in MOSFETs used for ultra-low-power applications [5]–[7].
