High-quality superconducting α-Ta film sputtered on heated silicon substrate

Abstract

Intrigued by the discovery of the long lifetime in the α-Ta/Al2O3-based Transmon qubit, researchers recently found α-Ta film is a promising platform for fabricating multi-qubits with long coherence time. To meet the requirements for integrating superconducting quantum circuits, the ideal method is to grow α-Ta film on a silicon substrate compatible with industrial manufacturing. Here we report the α-Ta film sputter-grown on Si (100) with a low-loss superconducting TiNx buffer layer. The α-Ta film with a large growth temperature window has a good crystalline character. The superconducting critical transition temperature (Tc) and residual resistivity ratio (RRR) in the α-Ta film grown at 500 °C are higher than that in the α-Ta film grown at room temperature (RT). These results provide crucial experimental clues toward understanding the connection between the superconductivity and the materials' properties in the α-Ta film and open a new route for producing a high-quality α-Ta film on silicon substrate for future industrial superconducting quantum computers.

References in corpus (14)

• Observation of high coherence in Josephson junction qubits measured in a three-dimensional circuit QED architecture
• New material platform for superconducting transmon qubits with coherence times exceeding 0.3 milliseconds
• Planar Superconducting Resonators with Internal Quality Factors above One Million
• Transmon qubit with relaxation time exceeding 0.5 milliseconds
• Surface participation and dielectric loss in superconducting qubits
• Materials loss measurements using superconducting microwave resonators
• Low Loss Superconducting Titanium Nitride Coplanar Waveguide Resonators
• Variation of transition temperatures and residual resistivity ratio in vapor-grown FeSe
• Investigating surface loss effects in superconducting transmon qubits
• Enhanced coherence of all-nitride superconducting qubits epitaxially grown on silicon substrate
• Substrate surface engineering for high-quality silicon/aluminum superconducting resonators
• High quality superconducting niobium films produced by Ultra High Vacuum Cathodic Arc
• UCSB final report for the CSQ program: Review of decoherence and materials physics for superconducting qubits
• Fabrication of Deep-Sub-Micrometer NbN/AlN/NbN Epitaxial Junctions on a Si Substrate

Cited by in corpus (2)

• Revealing the Origin and Nature of the Buried Metal-Substrate Interface Layer in Ta/Sapphire Superconducting Films
• Stable and low loss oxide layer on α-Ta (110) film for superconducting qubits