CMB-S4 detector wafer fabrication sites continue to optimize prototype pixel layouts and critical sub-component fabrication methods. Our industrial partner, SEEQC, has successfully produced a full prototype wafer for the Small Aperture Telescope (SAT) mid-frequency range. L3 system manager, Aritoki Suzuki, can be seen in the below image reflected within the intricate detector pattern. A zoomed in photo of the pixel layout is shown in the second photo. As a next step, the circular wafer will be diced into a hexagonal shape and subsequently tested in a dilution refrigerator cryostat at LBNL. CMB-S4 aims to prototype wafer types in key frequency ranges before finalizing the experiment’s conceptual detector designs.
Originally posted in the CMB-S4 February 2023 Newsletter