Developments Toward a 250-nm, Fully Planarized Fabrication Process With Ten Superconducting Layers And Self-Shunted Josephson Junctions

Sergey K. Tolpygo; Vladimir Bolkhovsky; Ravi Rastogi; Scott Zarr; Alexandra L. Day; Terence J. Weir; Alex Wynn; Leonard M. Johnson

doi:10.1109/isec.2017.8314189

arXiv · 1704.07683

Developments Toward a 250-nm, Fully Planarized Fabrication Process With Ten Superconducting Layers And Self-Shunted Josephson Junctions

Sergey K. Tolpygo·Vladimir Bolkhovsky·Ravi Rastogi·Scott Zarr·Alexandra L. Day·Terence J. Weir·Alex Wynn·Leonard M. Johnson

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Abstract

We are developing a superconductor electronics fabrication process with up to nine planarized superconducting layers, stackable stud vias, self-shunted Nb/AlOx-Al/Nb Josephson junctions, and one layer of MoNx kinetic inductors. The minimum feature size of resistors and inductors in the process is 250 nm. We present data on the mutual inductance of Nb stripline and microstrip inductors with linewidth and spacing from 250 nm to 1 {\mu}m made on the same or adjacent Nb layers, as well as the data on the linewidth and resistance uniformity.

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Sergey K. Tolpygo, Vladimir Bolkhovsky, Ravi Rastogi, Scott Zarr, Alexandra L. Day, Terence J. Weir, Alex Wynn, Leonard M. Johnson. 2017-04-25. Developments Toward a 250-nm, Fully Planarized Fabrication Process With Ten Superconducting Layers And Self-Shunted Josephson Junctions. https://doi.org/10.1109/isec.2017.8314189

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