Silicon-on-insulator membrane SIS mixers for Africa millimeter telescope Band 6+7 operation
National Radio Astronomy Observatory
Authors:
Jee-Ho Kim, Faouzi Boussaha, Christine Chaumont, Michele Piscitelli, Josiane Firminy, Etienne Eustache, Fabrice Stoppani, Andrey Baryshev, Boon Kok Tan
Abstract:
We present the design, simulation, fabrication, and initial characterization efforts toward a broadband superconductor-insulator-superconductor (SIS) mixer covering ALMA Bands 6 and 7 (211–373 GHz) on a single chip. The mixer employs a twin-junction SIS architecture integrated on a 10 µm-thick silicon-on-insulator (SOI) membrane substrate and is intended as a building block for future sideband-separating and dual-polarization receivers. To support the fabrication of these devices, front-side SIS circuit processing, SOI membrane release techniques, and gold beam-lead integration have been developed and refined. Initial device-release trials have successfully produced mixer chips with intact membranes and beam leads, while experimental setup for cryogenic mixer characterization has also been completed.
