Sofradir SWIR hyperspectral detectors for space applications

The field of SWIR detectors for space applications is strongly growing those last years, mainly because of the increasing need for environmental missions in the SWIR detection range. For now more than 10 years, Sofradir is involved in that field, developing and improving its SWIR detectors technology, leading to a mature technology that enable to address most of missions needs in term of performances, but also with respect to hard environmental constraints. SWIR detection range at Sofradir has been qualified for space applications thanks to various programs already run (APEX or Bepi-Colombo programs) or currently running (Sentinel 2, PRISMA mission). For Sentinel 2, a 1280x3 with a 15μm pitch in the SWIR range (CTIA) has been developed and is currently being validated. 1000x256 or 500x256 arrays 30 μm pitch (called Saturn or Neptune detectors) have already been validated in terms of irradiation behavior, thermal cycling, and ageing. Specific package designs have been validated in terms of high levels of shocks and vibrations. In particular, for both Sentinel 2 and PRISMA programs, Sofradir has developed reliable packaging compatible with passive cooling. Recently, for PRISMA mission, Sofradir is extending its VISible to Short wave Infra-Red technology, called VISIR, to 1000x256 hyperspectral arrays. This technology has the huge advantage to enable detection in both visible and short wave detection range (0.4μm up to 2.5μm), thus limiting the number of needed channels for hyperspectral applications but also outshining the classical limitation of Silicon Visible detectors, for which the sensitivity is dramatically dropping above 0.9 μm. In this paper, we will focus on hyperspectral detectors available at Sofradir. Main general performances will be first described, with emphasize on the VISIR technology that has been recently developed and which enable to cover simultaneously the Visible and SWIR ranges [0.4-2.5μm] with a single detector. Then some complete configurations (Focal Plane Array integrated in a Detector Dewar) suitable for airborne or space applications will be presented. Finally, a brief overview of reliability and tolerance to radiations of those detectors will be given.