Device Circuit Interactions for Steep Switching Slope Devices

Open Access
Author:
Liu, Huichu
Graduate Program:
Electrical Engineering
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
November 19, 2014
Committee Members:
  • Vijaykrishnan Narayanan, Committee Chair
  • Suman Datta, Committee Chair
  • Jerzy Ruzyllo, Committee Member
  • Joshua Alexander Robinson, Committee Member
Keywords:
  • Tunneling-field-effect-transistor
  • device-circuit interaction
  • steep subthreshold slope
  • energy efficiency
  • soft error reliability
Abstract:
Energy efficiency limit has becomes the main obstacle for the power-constrained applications using the conventional silicon complementary metal-oxide-semiconductor (CMOS) technology. In particular, the supply voltage scaling has slowed down in the past few technology generations due to the 60 mV/decade fundamental limit for on-off switching, which prevents the reduction of the energy per operation in today’s circuits and systems. To mitigate this challenge, tunneling-field-effect-transistor (TFET), as a viable alternative, has been proposed to achieve steep on-off switching at low supply voltages. Driven by the on-going progress of TFET prototype device development and its device characteristics applicable for different applications, co-design of TFET device-to-circuit is not only critical to transform the technology advantages into various application domains, but also important to evaluate its potential challenges. This dissertation has been dedicated to developing the simulation frameworks to model the III-V semiconductor material based TFETs from devices to circuits and system architectures. Based on the layers of abstractions, the impact of the steep sub-threshold slope, the asymmetrical source/drain, the uni-directional conduction as well as the digital and analog/RF metrics are explored for III-V TFETs. These unique device characteristics of TFETs are essential to enable the circuit design innovations and expand energy efficient application landscapes such as ultra-low power energy scavenging systems and body sensor nodes. Moreover, due to their low-voltage operation and the difference in the material systems and device designs, the reliability issues such as radiation induced single-event upsets, process variations as well as the parasitic effects of TFETs need to be evaluated from practical application perspectives, which are also addressed in this work.