VLIWR HgCdTe staring focal plane array development

Atmospheric remote-sensing have been one of the primary drivers toward longer wavelength infrared sensors beyond the 8 to 12 um atmospheric window typically used for terrestrial imaging systems. This paper presents the recent performance improvement attained with very long wavelength infrared (VLWIR) focal plane arrays, by the stringent control of the small bandgap HgCdTe material quality. Array operability is further enhanced by design using a 2:1 super-pixel detector format scheme with programmable bad element de-select and our new detector input offset optimization circuitry within each unit cell. Focal plane arrays with peak quantum efficiencies in excess of 80 percent, and cutoff wavelengths out to 15 μm have NEI operabilities around 95 percent for mid 1014 ph/s-cm2 fluxes operating near 50 K. Average NEI of 3.5 x 1010 ph/s-cm2 was demonstrated for a 14 μm cutoff wavelength focal plane array, consisting of over 55,000 elements, operating with an effective sample time of 87.5 ms.

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