nBn based infrared detectors using type-II InAs/(In,Ga)Sb superlattices

for 16.3 ms integration time. The peak responsivity and detectivity of FPA were estimated to be 1.6 A/W and 6.7 x 10 11
Jones, respectively, at 3.8 µm and 77K.
We then described our implementation of the nBn concept to design SL LWIR detectors. Within addition to the
expected long-wave cut off wavelength, the nBn LWIR detector structure demonstrated two color response (λ c1 ~ 3.5 µm
and λ c2 ~ 8.0 µm) under different polarity of applied bias.
Finally, a multispectral nBn detector structure has been presented. The dual band response (λ c1 ~ 4.5 µm and
λ c2 ~ 8 µm) was achieved by changing the polarity of applied bias. The spectral response shows a significant change in
the LWIR to MWIR ratio within a very small bias range (100 mV), making it compatible with commercially available
readout integrated circuits.
6. ACKNOWLEDGEMENT
Support from AFRL Grant FA9453-07-C-0171 and HOT MWIR program is acknowledged.
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