Hybrid phase-change — Tunnel FET (PC-TFET) switch with subthreshold swing < 10mV/decade and sub-0.1 body factor: Digital and analog benchmarking

Abstract

In this paper we report the first hybrid Phase-Change - Tunnel FET (PC-TFET) device configurations for achieving a deep sub-thermionic steep subthreshold swing at room temperature and subthreshold power savings. The proposed hybrid device feedbacks the steep transition of Metal-Insulator transition in a VO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> structure into Gate or Source configurations of strained silicon nanowire Tunnel FETs, to achieve a switching with lon/Ioff better that 5.5×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> and with a subthreshold swing of 4.0 mV/dec at 25 °C. We demonstrate that the principle of PC-TFET switching relates to an internal amplification resulting in a sub-unity body factor, m, which is reduced to values below 0.1 for a current range larger than 2-3 decades. We report a full experimental digital and analog benchmarking of the new device and compare it with Tunnel FETs and CMOS. Remarkably, the PC-TFET can achieve analog figures of merit like gm/Id breaking the 40 V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> limit of MOSFETs. We demonstrate and report the first buffered oscillator cell for neuromorphic computing exploiting the gate configuration of PC-TFET.