Single-Walled Carbon Nanotubes as Shadow Masks for Nanogap Fabrication

TL;DR

This paper introduces a novel method using single-walled carbon nanotubes as shadow masks to create nanogaps in metal wires, enabling precise fabrication for molecular electronics with high tunneling characteristics.

Contribution

The study presents a new shadow mask technique employing carbon nanotubes for nanogap fabrication, achieving consistent sub-3 nm gaps suitable for molecular transport studies.

Findings

Over 80% of devices show tunneling behavior.

Gap widths range from 0.8 to 2.3 nm.

Method is effective for single-molecule transport applications.

Abstract

We describe a technique for fabricating nanometer-scale gaps in Pt wires on insulating substrates, using individual single-walled carbon nanotubes as shadow masks during metal deposition. More than 80% of the devices display current-voltage dependencies characteristic of direct electron tunneling. Fits to the current-voltage data yield gap widths in the 0.8-2.3 nm range for these devices, dimensions that are well suited for single-molecule transport measurements.