Tunneling devices and applications in high functionality/speed digital circuits

Abstract

Tunneling phenomena can be used to realize devices with unique I-V characteristics (negative differential resistance) which can be employed to design various types of digital circuits with a significantly lower number of transistors, extremely fast switching speeds, very low power consumption and pipelining capability at the basic gate level (nanopipelining) which results in higher system throughput. In this article, we will present the basic properties of various types of devices which have been proposed for these applications including resonant tunneling diodes (RTDs), Esaki tunnel diodes (ETDs), and various types of transistors including resonant hot electron transistors (RHETs) and tunneling bipolar transistors (TBTs). We will also compare the anticipated performance of various types of logic gates and digital circuit implementations utilizing these devices with conventional CMOS circuits.