Universal quantum computers promise to solve computational problems that
are beyond the capabilities of known classical algorithms. To realize
such quantum hardware on a superconducting material platform, a vast
number of physical qubits has to be manufactured and integrated at high
quality and uniformity on a chip. Anticipating the benefits of
semiconductor industry processes in terms of process control, uniformity
and repeatability, we set out to manufacture superconducting quantum
circuits in a semiconductor fabrication facility. In order to set a
baseline for the process quality, we report on the fabrication of
coplanar waveguide resonators in a 200 mm production line, making use of
a two-layer superconducting circuit technology. We demonstrate high
material and process quality by cryogenic Q-factor measurements
exceeding

in the single-photon regime, for microwave resonators made of both
Niobium and Tantalum. In addition, we demonstrate the incorporation of
superconducting Niobium air bridges in our process, while maintaining
the high quality factor of Niobium resonators.
Link to the article is here.