Materials Summary

Superconducting Materials

Quick comparison table for superconducting material selection.

Material

Type

Tc

Primary Use

Aluminum (Al)

Superconductor

1.2 K

Qubit body, JJ electrodes

Niobium (Nb)

Superconductor

9.3 K

Resonators, wiring layers

Silicon (Si)

Substrate

Qubit chip foundation

Sapphire (Al₂O₃)

Substrate

High-coherence substrate

Titanium Nitride (TiN)

Compound SC

4–5.6 K

High-kinetic-inductance elements

Niobium Nitride (NbN)

Compound SC

16 K

SNSPDs, resonators

NbTiN

Compound SC

15 K

High-Q resonators, SQUIDs

AlOx (tunnel barrier)

Dielectric

Josephson junction tunnel barrier

MoRe alloy

Superconductor

9–14 K

Hybrid / topological qubits

Indium (In)

Superconductor

3.4 K

3D flip-chip bump bonds