Superconducting TiN through-silicon-vias for quantum technology

Abstract

Through-silicon vias (TSVs) can be used to route signals and to obtain effective grounding in microwave circuits. The coating of the TSVs with a superconducting material is a challenge because of the high aspect ratio of the structures. In this paper, we present successful fabrication of superconducting $60\ \mu \mathrm{m}$ diameter TSVs, coated by atomic layer deposition (ALD) of titanium nitride. The critical temperature Tc is approximately 1.6 K.