Tunneling field effect transistors for energy efficient digital, RF and power management circuit designs enabling IoT edge computing platforms

Abstract

In this chapter, we have studied the device structure and characteristics of TFETs for energy-efficient circuit design useful for IoT edge computing platforms. TFET shows better electrical characteristics in terms of SS, transconductance, current efficiency, and device FoM. Unlike MOSFETs, TFETs exhibit distinct electrical properties like ambipolar conduction and unidirectional current conduction. TFET-based digital logic gates and buffer circuits are analyzed and benchmarked with Si FinFET for energy efficiency. TFETs outperform FinFET designs and achieve better energy efficiency at low V DD . Due to the high ON-current of the devices, TFET RO reports a frequency of 21 GHz, whereas FinFET RO achieves 13 GHz under similar design conditions. It was shown that due to the enhanced Miller capacitance effect in TFETs, transient characteristics of TFET RO suffers from high overshoots and undershoots. We further looked into TFET-based VCRO design wherein TFET design achieves wide tuning range compared to FinFET designs. Finally, we demonstrate TFET-based DLDO achieving low quiescent current with high-energy efficiency. In summary, TFETs have some unique characteristics that make them an ideal candidate for low voltage IoT platforms with specific design challenges to circuit and system design community as discussed.