Theoretical and Experimental Studies of Schottky Diodes That Use Aligned Arrays of Single Walled Carbon Nanotubes

TL;DR

This paper combines theoretical modeling and experimental validation to analyze Schottky diodes made from aligned single-walled carbon nanotubes, highlighting how device design influences rectification performance.

Contribution

It introduces a simple physical model for these diodes and demonstrates how eliminating metallic nanotube shunts improves rectification ratios.

Findings

Array diodes initially have low rectification due to metallic nanotube shunts.

Applying a voltage sweep can eliminate shunts, enhancing rectification.

Channel resistance limits device performance more than nanotube diode properties.

Abstract

We present theoretical and experimental studies of Schottky diodes that use aligned arrays of single walled carbon nanotubes. A simple physical model, taking into account the basic physics of current rectification, can adequately describe the single-tube and array devices. We show that for as grown array diodes, the rectification ratio, defined by the maximum-to-minimum-current-ratio, is low due to the presence of m-SWNT shunts. These tubes can be eliminated in a single voltage sweep resulting in a high rectification array device. Further analysis also shows that the channel resistance, and not the intrinsic nanotube diode properties, limits the rectification in devices with channel length up to ten micrometer.