Our work on ‘Electromigrated Gold Nanogap Tunnel Junction Arrays: Fabrication and Electrical Behavior in Liquid and Gaseous Media‘ has been published in ACS Applied Materials & Interfaces. The associated work on the measurement setup has also been published in Review of Scientific Instruments, titled ‘High-bandwidth low-current measurement system for automated and scalable probing of tunnel junctions in liquids‘.
The first article introduces feedback-controlled electromigration to fabricate stable gold nanogap tunnel junctions for single-molecule sensors capable of operating robustly across various liquid and gaseous environments. We systematically examine both the electrical behaviour and the yield of junction formation across different media, with attention to how specific operating conditions influence stability and performance. The findings not only advance our understanding of tunnel junction scalability and production but also enhance the potential for integrating these sensors into practical, compact devices.
In the second article, we describe an innovative measurement setup that supports high-bandwidth (>10 kHz) and low-current (pA–nA) measurements, crucial for the effective probing of these tunnel junctions. By integrating a custom two-terminal probe with a 100 kHz bandwidth amplifier and automating the data acquisition within a noise-reducing Faraday cage, we have streamlined the scalability and improved the precision of these measurements.