Qualification of Microwave SQUID Multiplexer Chips for Simons Observatory

Dante Jones, Robinjeet Singh, Jason Austermann, J. A. Beall, David Daniel, Shannon M. Duff, Daniel Dutcher, John Groh, Johannes Hubmayr, Bradley R. Johnson, Richard Lew, Michael J. Link, Tammy J. Lucas, John A.B. Mates, Suzanne Staggs, Joel Ullom, Leila Vale, Jeffery Van Lanen, Michael Vissers, Yuhan Wang

Research output: Contribution to journalArticlepeer-review


The Simons Observatory is a cosmic microwave background experiment stationed atop Cerro Toco, at an elevation of 5200 ms in Chile’s Atacama Desert. The receivers of the Observatory will contain more than 60,000 transition edge sensor bolometers. In order to read out this large detector count in a scalable manner, we utilize a microwave superconducting quantum interference device (SQUID) multiplexing scheme where each detector is inductively coupled to an rf SQUID, which in turn is inductively coupled to a GHz resonator. More than 2000 SQUIDs and resonators are fabricated on a single 76.2-mm-diameter silicon wafer. To qualify wafers before integration, we cryogenically screen ∼ 10% of the devices on each wafer by use of a standard set of measurements. From these data, we report parameter value trends in 47 wafers that were fabricated in the past two years. We show good control in key parameters such as frequency placement, internal quality factor, and response to applied flux. We demonstrate a wafer acceptance yield of 86%.

Original languageEnglish (US)
JournalJournal of Low Temperature Physics
StateAccepted/In press - 2024

All Science Journal Classification (ASJC) codes

  • Atomic and Molecular Physics, and Optics
  • General Materials Science
  • Condensed Matter Physics


  • Bolometer
  • CMB
  • TES
  • μmux


Dive into the research topics of 'Qualification of Microwave SQUID Multiplexer Chips for Simons Observatory'. Together they form a unique fingerprint.

Cite this