Abstract
Recently, large format and high quantum efficiency corrugated quantum well infrared photodetector (C-QWIP) FPAs
have been demonstrated. Since the detector light coupling scheme does not alter the intrinsic absorption spectrum of the
material, the QWIPs can now be designed with different bandwidths and lineshapes to suit various applications.
Meanwhile, the internal optical field distribution of the C-QWIPs is different from that of a grating coupled detector, the
material structure thus should be designed and optimized differently with respect to quantum efficiency, conversion
efficiency and operating temperature. In this paper, we will provide a framework for the material design. Specifically,
we will present a theoretical detector performance model and discuss two specific examples, namely with 9.2 and 10.2
μm cutoff wavelengths. We found that for both λc, the photocurrent to dark current ratio is maximized at an electron
doping density ND of 0.28 × 1018 cm-3. The dark current limited detectivity meanwhile reaches a maximum at a higher
ND of 0.45 × 1018 cm-3. But the lowest noise equivalent noise temperature difference is actually obtained at an even
higher ND of 1.0 × 1018 cm-3 due to the larger quantum efficiency, if there are no limitations on the readout charge
capacity. These predictions are compared with the data of a 1024 × 1024 C-QWIP FPA hybridized to a fan-out circuit,
and the results are consistent.
