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arXiv · 2306.09568

Epitaxial {\alpha}-Ta (110) film on a-plane sapphire substrate for superconducting qubits on wafer scale

Boyi Zhou·Lina Yang·Tao Wang·Yanfu Wu·Kanglin Xiong·Jiagui Feng
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Abstract

Realization of practical superconducting quantum computing requires many qubits of long coherence time. Compared to the commonly used Ta deposited on c-plane sapphire, which occasionally form {\alpha}-Ta (111) grains and \b{eta}-tantalum grains, high quality Ta (110) film can grow epitaxial on a-plane sapphire because of the atomic relationships at the interface. Well-ordered {\alpha}-Ta (110) film on wafer-scale a-plane sapphire has been prepared. The film exhibits high residual resistance ratio. Transmon qubits fabricated using these film shows relaxation times exceeding 150 {\mu}s. The results suggest Ta film on a-plane sapphire is a promising choice for long coherence time qubit on wafer scale.

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Boyi Zhou, Lina Yang, Tao Wang, Yanfu Wu, Kanglin Xiong, Jiagui Feng. 2023-06-16. Epitaxial {\alpha}-Ta (110) film on a-plane sapphire substrate for superconducting qubits on wafer scale. https://doi.org/10.35848/1347-4065%2Facfde6

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