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arXiv · 2102.06123

Microscopic metallic air-bridge arrays for connecting quantum devices

Y. Jin·M. Moreno·P. M. T. Vianez·W. K. Tan·J. P. Griffiths·I. Farrer·D. A. Ritchie·C. J. B. Ford
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Abstract

We present a single-exposure fabrication technique for a very large array of microscopic air-bridges using a tri-layer resist process with electron-beam lithography. The technique is capable of forming air-bridges with strong metal-metal or metal-substrate connections. This was demonstrated by its application in an electron tunnelling device consisting of 400 identical surface gates for defining quantum wires, where the air-bridges are used as suspended connections for the surface gates. This technique enables us to create a large array of uniform one-dimensional channels that are open at both ends. In this article, we outline the details of the fabrication process, together with a study and the solution of the challenges present in the development of the technique, which includes the use of water-IPA (isopropyl alcohol) developer, calibration of resist thickness and numerical simulation of the development.

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Y. Jin, M. Moreno, P. M. T. Vianez, W. K. Tan, J. P. Griffiths, I. Farrer, D. A. Ritchie, C. J. B. Ford. 2021-02-11. Microscopic metallic air-bridge arrays for connecting quantum devices. https://doi.org/10.1063/5.0045557

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