Title :
640×486 long-wavelength two-color GaAs/AlGaAs quantum well infrared photodetector (QWIP) focal plane array camera
Author :
Gunapala, Sarath D. ; Bandara, Sumith V. ; Singh, A. ; Liu, John K. ; Rafol, Sir B. ; Luong, E.M. ; Mumolo, Jason M. ; Tran, Nhan Q. ; Ting, David Z Y ; Vincent, J.D. ; Shott, Craig A. ; Long, J. ; LeVan, Paul D.
Author_Institution :
Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA
fDate :
5/1/2000 12:00:00 AM
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 640×486 format monolithically integrated 8-9 and 14-15 μm two-color (or dual wavelength) QWIP focal plane arrays (FPAs). These FPAs were then hybridized to 640×486 silicon CMOS readout multiplexers. A thinned (i.e., substrate removed) FPA hybrid was integrated into a liquid helium cooled dewar for electrical and optical characterization and to demonstrate simultaneous two-color imagery. The 8-9 μm detectors in the FPA have shown background limited performance (BLIP) at 70 K operating temperature for 300 K background with f/2 cold stop. The 14-15 μm detectors of the FPA reaches BLIP at 40 K operating temperature under the same background conditions. In this paper we discuss the performance of this long-wavelength dualband QWIP FPA in terms of quantum efficiency, detectivity, noise equivalent temperature difference (NEΔT), uniformity, and operability
Keywords :
III-V semiconductors; aluminium compounds; focal planes; gallium arsenide; hybrid integrated circuits; infrared detectors; molecular beam epitaxial growth; photodetectors; quantum well devices; semiconductor quantum wells; 14 to 15 micron; 3 in; 311040 pixel; 40 to 70 K; 486 pixel; 640 pixel; 8 to 9 micron; FPA hybrid; GaAs; GaAs-AlGaAs; GaAs/AlGaAs QW IR photodetector; MBE; QWIP focal plane array camera; Si; Si CMOS readout multiplexers; background limited performance; detectivity; dual wavelength FPAs; electrical characterization; liquid helium cooled dewar; long-wavelength IR photodetector; molecular beam epitaxy; noise equivalent temperature difference; operability; optical characterization; quantum efficiency; semi-insulating GaAs substrate; two-colour infrared photodetector; uniformity; Design optimization; Detectors; Gallium arsenide; Helium; Molecular beam epitaxial growth; Multiplexing; Photodetectors; Silicon; Substrates; Temperature;
Journal_Title :
Electron Devices, IEEE Transactions on
