Design and Investigation of Charge-Plasma-Based Work Function Engineered Dual-Metal-Heterogeneous Gate Si-Si_0.55Ge_0.45 GAA-Cylindrical NWTFET for Ambipolar Analysis

Abstract

In this paper, we have proposed dopingless gate all around (GAA) nanowire tunnel field-effect transistor (NWTFET) made up of dual-material channel (DMaC). Charge-plasma (CP) technique is used to induce the doping concentration of charge carriers in the intrinsic semiconductor. GAA structure uses zirconium silicate (IV) (ZrSiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> )/silicon dioxide (SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) for heterogeneous gate (HG) structure metalized with two different gate metals. Auxiliary gate (GM1) and tunneling gate (GM2) have different work functions, i.e., φ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> and φ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> . The device physics is analyzed using electric field, charge carrier concentration, energy-band diagram, and tunneling rate across the structure. The effect of variation in φ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> and φ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> helps in the analysis of the ambipolar and analog behavior of the proposed device CP-dual metal-HG-DMaC-NWTFET. The reported ON-state current is 5.54 μA/μm, and the OFF-state current is approximately 0.1 aA/μm. The proposed device showed negligible ambipolar current (10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-19</sup> A/μm) as negative bias increases to V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GS</sub> = -0.8 V making the device compatible for low-voltage applications.