Translator Disclaimer
26 June 1996 Focal plane performance for the AIRS instrument
Author Affiliations +
Higher resolution and wider IR spectral coverage is needed to improved infrared sounding instruments. The Atmospheric Infrared Sounder (AIRS), chosen by NASA to fly on the Earth Observing System, addresses these needs with advanced PV HgCdTe detector arrays designed to cover the spectral range from 3.7 micrometers to 13.6 micrometers with an average resolution of (lambda) /(Delta) (lambda) equals 1200. High performance detectors and advanced readout integrated circuit electronics make it possible to meet mission requirements. For convenience, the AIRS focal plane has been partitioned into four MWIR modules spanning the spectral range from 3.7 micrometers to 8.22 micrometers , and six LWIR modules for wavelengths above 8.8 micrometers . This paper focuses on the AIRS readout device and recent developments in p-on-n heterojunction detector technology at Loral. The detector arrays, operating at 60 K, readily satisfies the requirements of the AIRS instrument. Detector arrays with 4.7 micrometers cutoff wavelength at 60 K and 20 mV reverse bias have RdAs typically greater than 1010 (Omega) (DOT) cm2, with dark signals less than 0.6 fA and detector capacitances less than 0.6 pf for a 50 micrometers by 10 micrometers detector. AR coated MW arrays exhibit quantum efficiencies of greater than 80 percent. Reverse breakdowns are more than -150 mV. Module data for 15.1 micrometers detectors with anti-reflection coating exhibit quantum efficiencies greater than 70 percent and dark currents less than 8 nanoamps at 20 mV reverse bias. Also, excellent module linearity meeting the AIRS stringent requirements is achieved. Of course, measurements of MW detectors require extremely high gain transimpedance amplifiers. The AIRS MWIR readout structures prove to be exceptional in their ability to characterize these high impedance detectors. The charge sensitive input amplifiers on these readout devices utilize an equivalent input integration capacitor of less than 10 fFd to achieve ultrahigh transimpedance gain, and reset noise is suppressed with on focal plane correlated double sampling. LWIR readouts use ultralow noise buffered direct injection preamplifiers. The readouts have a robust architectures with differential input and outputs to minimize EMI and built in redundancy for survivability. Description of the readout device is presented, as well as linearity measurements of both the readout and complete modules.
© (1996) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
James A. Stobie, James D. Garnett, Eric E. Krueger, Andrew M. Siegel, and James H. Rutter Jr. "Focal plane performance for the AIRS instrument", Proc. SPIE 2745, Infrared Readout Electronics III, (26 June 1996);


Advanced MCT technologies in France
Proceedings of SPIE (May 14 2007)
SWIR to LWIR HgCdTe detectors and FPAs for remote sensing...
Proceedings of SPIE (October 21 2005)
Two-color HgCdTe infrared staring focal plane arrays
Proceedings of SPIE (December 08 2003)
State-of-the-art HgCdTe infrared devices
Proceedings of SPIE (April 13 2000)
Cross-track infrared sounder FPAA performance
Proceedings of SPIE (January 23 2003)

Back to Top