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arXiv · 2403.19614

Optimizing Josephson Junction Reproducibility in 30 kV E-beam Lithography: Analysis of Backscattered Electron Distribution

A. M. Rebello·L. M. Ruela·G. Moreto·N. Y. Klein·E. Martins·I. S. Oliveira·F. Rouxinol·J. P. Sinnecker
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Abstract

This paper explores methods to enhance the reproducibility of Josephson junctions, crucial elements in superconducting quantum technologies, when employing the Dolan technique in 30 kV e-beam processes. The study explores the influence of dose distribution along the bridge area on reproducibility, addressing challenges related to fabrication sensitivity. Experimental methods include E-beam lithography, with electron trajectory simulations shedding light on backscattered electron behavior. We demonstrate the fabrication of different junction geometries, revealing that some geometries significantly improve reproducibility by resulting in a more homogeneous dose distribution over the junction area.

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A. M. Rebello, L. M. Ruela, G. Moreto, N. Y. Klein, E. Martins, I. S. Oliveira, F. Rouxinol, J. P. Sinnecker. 2024-03-28. Optimizing Josephson Junction Reproducibility in 30 kV E-beam Lithography: Analysis of Backscattered Electron Distribution. https://arxiv.org/abs/2403.19614

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