Highly-Conformal Sputtered Through-Silicon Vias With Sharp Superconducting Transition

This paper describes the microfabrication and electrical characterization of aluminum-coated superconducting through-silicon vias (TSVs) with sharp transition above 1 K. The was achieved by means fully conformal void-free DC-sputtering TSVs Al, is here demonstrated in up to $500~\mu \text{m}$ -deep vias. Full conformality Al sputtering made possible shaping a tailored hourglass profile, which allowed metallic layer as thick 430 nm be deposited center Single-via electric resistance low 160 $\text{m}\Omega $ at room temperature superconductivity 1.27 K were measured three-dimensional (3D) cross-bridge Kelvin resistor structure. work establishes CMOS-compatible fabrication process suitable for arrays 3D integration silicon-based devices. [2020-0354]