Temperature Control of Electromigration to form Gold Nanogap Junctions

TL;DR

This paper investigates temperature-controlled electromigration of gold nanowires to reliably create nanogap junctions, highlighting the importance of feedback mechanisms and series resistance minimization for precise fabrication.

Contribution

It demonstrates a linear relationship between nanowire cross-sectional area and dissipated power, and shows how feedback controls temperature to prevent thermal runaway during electromigration.

Findings

Linear correlation between cross-sectional area and dissipated power

Feedback mechanism effectively controls junction temperature

Series resistance minimization enables controlled electromigration

Abstract

Controlled electromigration of gold nanowires of different cross-sectional areas to form nanogap junctions is studied using a feedback method. A linear correlation between the cross sectional area of the gold nanowires and the power dissipated in the junction during electromigration is observed, indicating that the feedback mechanism operates primarily by controlling the temperature of the junction during electromigration. We also show that the role of the external feedback circuit is to prevent thermal runaway; minimization of series resistance allows controlled electromigration to a significant range of junction resistances with a simple voltage ramp.