Atomistic Modeling of Suspended Carbon Nanotube Field Effect Transistors Under Proton Radiation

We present an atomistic model explaining spontaneous reductions of source-drain current in suspended carbon nanotube field effect transistors (CNT FETs) under proton irradiation. The non-equilibrium Green's function (NEGF) method is used to investigate the local density of states (LDOS) and transfer characteristics of the device. Our model suggests that ionized gas species within 20 nm of the CNT FET will act as an electrostatic gate, reducing current in the device for low back-gate voltages.

I. Introduction

Carbon nanotubes (CNTs) provide an exciting platform for studying quantum transport. They exhibit one-dimensional characteristics, carry high current density, and have large band-gaps that scale with tube diameter [1]. CNTs are of great interest to the semiconductor industry as a channel material for aggressively scaled field effect transistors (FETs) [2]–[10]. The interesting physics and potential application of CNT FETs warrant exhaustive study and thorough understanding.