Abstract
Detecting the primordial ’B-mode’ polarization of the cosmic microwave background is one of the major challenges of modern observational cosmology. Microwave telescopes need sensitive cryogenic bolometers with an overall equivalent noise temperature in the nK range. In this paper, we present the development status of large area (about 1 cm\(^{2})\) spider-web bolometer, which imply additional fabrication challenges. The spider-web is a suspended Si\(_{3}\)N\(_{4}\) 1 \(\upmu \)m-thick and 8-mm diameter with mesh size of 250 \(\upmu \)m. The thermal sensitive element is a superconducting transition edge sensor (TES) at the center of the bolometer. The first prototype is a Ti–Au TES with transition temperature tuned around 350 mK, new devices will be a Mo–Au bilayer tuned to have a transition temperature of 500 mK. We present the fabrication process with micro-machining techniques from silicon wafer covered with SiO\(_{2}\) - Si\(_{3}\)N\(_{4}\) CVD films, 0.3 and 1 \(\upmu \)m- thick, respectively, and preliminary tests.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
