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arXiv · 2010.12090

Ultrahigh Vacuum Packaging and Surface Cleaning for Quantum Devices

M. Mergenthaler·S. Paredes·P. Müller·C. Müller·S. Filipp·M. Sandberg·J. Hertzberg·V. P. Adiga·M. Brink·A. Fuhrer
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Abstract

We describe design, implementation and performance of an ultra-high vacuum (UHV) package for superconducting qubit chips or other surface sensitive quantum devices. The UHV loading procedure allows for annealing, ultra-violet light irradiation, ion milling and surface passivation of quantum devices before sealing them into a measurement package. The package retains vacuum during the transfer to cryogenic temperatures by active pumping with a titanium getter layer. We characterize the treatment capabilities of the system and present measurements of flux tunable qubits with an average T$_1=84~\mu$s and T$^{echo}_2=134~\mu$s after vacuum-loading these samples into a bottom loading dilution refrigerator in the UHV-package.

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M. Mergenthaler, S. Paredes, P. Müller, C. Müller, S. Filipp, M. Sandberg, J. Hertzberg, V. P. Adiga, M. Brink, A. Fuhrer. 2020-10-22. Ultrahigh Vacuum Packaging and Surface Cleaning for Quantum Devices. https://doi.org/10.1063/5.0034574

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