Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Membrane-based HEB mixer for THz applications

Jean Baubert, Morvan C. Salez, Y. Delorme, P. Pons, Gregory N Gol'tsman, Harald Merkel, B. Leconte

Published Apr 25, 2003• 2 citations

Abstract

We report in this paper a new concept for 2.7 THz superconducting Niobium nitride (NbN) Hot-Electron Bolometer mixer (HEB). The membrane process was developped for space telecommnunication applications a few years ago and the HEB mixer concept is now considered as the best choice for low-noise submillimeter-wave frequency heterodyne receivers. The idea is then to join these two technologies. The novel fabrication scheme is to fabricate a NbN HEB mixer on a 1 μm thick stress-less Si3N4/SiO2 membrane. This seems to present numerous improvements concerning : use at higher RF frequencies, power coupling efficiency, HEB mixer sensitivity, noise temperature, and space applications. This work is to be continued within the framework of an ESA TRP project, a 2.7 THz heterodyne camera with numerous applications including a SOFIA airborne receiver. This paper presents the whole fabrication process, the validation tests and preliminary results. Membrane-based HEB mixer theory is currently being investigated and further tests such as heterodyne and Fourier transform spectrometry measurement are planed shortly.

DOI: 10.1117/12.499158

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