Lithography-free control of the position of single walled carbon nanotubes on a substrate by focused ion beam induced deposition of catalyst and chemical vapor deposition

TL;DR

This paper presents a lithography-free method using focused ion beam induced deposition to precisely position single-walled carbon nanotubes on a substrate, simplifying fabrication compared to traditional multistep lithography.

Contribution

It introduces a novel FIB-based catalyst deposition technique for direct, high-precision placement of SWCNTs during CVD growth, eliminating complex lithography steps.

Findings

Achieved high-resolution positioning of SWCNTs via in situ FIB deposition.

Demonstrated the method's advantages over traditional lithography-based techniques.

Enabled controlled placement of nanotubes at arbitrary substrate locations.

Abstract

We introduce a novel nanofabrication technique to directly deposit catalyst pads for the chemical vapor deposition synthesis of single-walled carbon nanotubes (SWCNTs) at any desired position on a substrate by Gallium focused ion beam (FIB) induced deposition of silicon oxide thin films from the metalorganic Tetraethyl orthosilicate (TEOS) precursor. A high resolution in the positioning of the SWCNTs is naturally achieved as the imaging and deposition by FIB are conducted concurrently in situ at the same selected point on the substrate. This technique has substantial advantages over the current state-of-the-art methods that are based on complex and multistep lithography processes.