Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization

Kevin L. Denis; Aamir Ali; John W. Appel; Charles L. Bennett; Meng-Ping Chang; David T. Chuss; Felipe Colazo; Nicholas Costen; Thomas Essinger-Hileman; Ron Hu; Tobias Marriage; Karwan Rostem; Kongpop U-Yen; Edward J. Wollack

doi:10.1007/s10909-015-1366-y

arXiv · 1511.05036

Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization

Kevin L. Denis·Aamir Ali·John W. Appel·Charles L. Bennett·Meng-Ping Chang·David T. Chuss·Felipe Colazo·Nicholas Costen·Thomas Essinger-Hileman·Ron Hu·Tobias Marriage·Karwan Rostem·Kongpop U-Yen·Edward J. Wollack

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Abstract

Characterization of the minute cosmic microwave background polarization signature requires multi-frequency, high-throughput precision instrument systems. We have previously described the detector fabrication of a 40 GHz focal plane and now describe the fabrication of detector modules for measurement of the CMB at 90 GHz. The 90 GHz detectors are a scaled version of the 40 GHz architecture where, due to smaller size detectors, we have implemented a modular (wafer level) rather than the chip-level architecture. The new fabrication process utilizes the same design rules with the added challenge of increased wiring density to the 74 TES's as well as a new wafer level hybridization procedure. The hexagonally shaped modules are tile-able, and as such, can be used to form the large focal planes required for a space-based CMB polarimeter. The detectors described here will be deployed in two focal planes with 7 modules each in the Johns Hopkins University led ground-based Cosmology Large Angular Scale Surveyor (CLASS) telescope.

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Kevin L. Denis, Aamir Ali, John W. Appel, Charles L. Bennett, Meng-Ping Chang, David T. Chuss, Felipe Colazo, Nicholas Costen, Thomas Essinger-Hileman, Ron Hu, Tobias Marriage, Karwan Rostem, Kongpop U-Yen, Edward J. Wollack. 2015-11-16. Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization. https://doi.org/10.1007/s10909-015-1366-y

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