PROCEEDINGS ARTICLE | September 16, 2011
Proc. SPIE. 8155, Infrared Sensors, Devices, and Applications; and Single Photon Imaging II
KEYWORDS: Near infrared, Electronics, Sensors, Data acquisition, Space telescopes, Charge-coupled devices, Silicon carbide, CCD image sensors, Signal detection, Flexible circuits
Mission concepts for NASA's Wide Field Infrared Survey Telescope (WFIRST)1,2, ESA's Euclid3,4 mission, as well as
next-generation ground-based surveys require large mosaic focal planes sensitive in both visible and near infrared (NIR)
wavelengths. We have developed space-qualified detectors, readout electronics and focal plane design techniques that
can be used to intermingle CCDs and NIR detectors on a single, silicon carbide (SiC) cold plate. This enables optimized,
wideband observing strategies. The CCDs, developed at Lawrence Berkeley National Laboratory, are fully-depleted, pchannel
devices that are backside illuminated and capable of operating at temperatures down to 120K. The NIR
detectors are 1.7 μm and 2.0 μm wavelength cutoff H2RG® HgCdTe, manufactured by Teledyne Imaging Sensors under
contract to LBNL. Both the CCDs and NIR detectors are packaged on 4-side abuttable SiC pedestals with a common
mounting footprint supporting a 44 mm mosaic pitch. Both types of detectors have direct-attached readout electronics
that convert the detector signal directly to serial, digital data streams and allow a flexible, low cost data acquisition
strategy to enable large data rates. A mosaic of these detectors can be operated at a common temperature that achieves
the required dark current and read noise performance necessary for dark energy observations. We report here the
qualification testing and performance verification for a focal plane that accommodates a 4x8 array of CCDs and HgCdTe
detectors.
