Characterization results of the TROPOMI Short Wave InfraRed detector

The TROPOMI Earth-observing instrument is the single payload on board ESA's Sentinel-5 Precursor mission. It is the successor of the Sciamachy instrument (ESA ENVISAT) and the OMI instrument (NASA EOS/Aura), and combines and improves the best of both instruments. TROPOMI copies the push broom observation geometry of OMI allowing for daily global coverage due to its instantaneous field of view of 108 degrees, or 2600 km swath on ground. From Sciamachy the 2305 - 2385 nm Short-Wave Infra-Red (SWIR) observational band is copied with which methane and carbon monoxide are observed. This paper reports on the development of the SWIR detector module and the detailed characterization of the 1000x256 SWIR Saturn detector array produced by Sofradir (F) as measured with the SRON-developed Front-End Electronics. The detailed characterization comprises not only the regular properties such as dark current, noise and photo-response, but also more complex characteristics including non-linearity and memory. Characterization of the detection module was performed for all operational parameters: detector temperature (135 - 145 K), bias voltage and integration time. Thanks to the detector-characterization program, the operational clocking of the detector could be optimized, resulting in significantly improved performance.