640 X 486 Long-Wavelength Two-Color GaAs/AlGaAs Quantum Well Infrared Photodetector (QWIP) Focal Plane Array Camera
Abstract
We have designed and fabricated an optimized long-wavelength/very-long-wavelength two-color quantum well infrared photodetector (QWIP) device structure. The device structure was grown on a 3-in semi- insulating GaAs substrate by molecular beam epitaxy (MBE) . The wafer was processed into several 640 x 486 format monolithically integrated 8-9 and 14-15 micrometers two-color (or dual wavelength) QWIP focal plane arrays (FPA's). These FPA's were then hybridized to 640 x 486 silicon CMOS readout multiplexers. A thinned (i.e., substrate removed) FPA hybrid was integrated into liquid helium cooled dewar for electrical and optical characterization and to demonstrate simultaneous two-color imagery. The 8-9 micrometers detectors in the FPA have shown background limited performance (BLIP) at 7O K operating temperature for 300 K background with f/2 cold stop. The 14-15 micrometers detectors of the SPA reach BLIP at 40 K operating temperature under the same background conditions. In this paper we discuss the performance of this long-wavelength dualband QWIP SPA in terms of quantum efficiency, detectivity, noise equivalent temperature difference (NE DELTA T), uniformity, and operability.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 13, 2000
- Accession Number
- ADA408670
Entities
People
- Anupama Singh
- J. K. Liu
- S. B. Rafol
- S. D. Gunapala
- S. V. Bandara
Organizations
- Air Force Research Laboratory