In this chapter we consider the current state of the art for detectors and FPAs fabricated on III-V materials. Again, considerations will be limited to data available in the open literature. There are two meaningful choices of architecture for III-V FPAs, namely, the photodiode and the barrier layer photoconductor. The many variations on these two themes are all bound by the limitations imposed by the short S-R lifetimes currently associated with III-V materials. The photodiode architecture exhibits large depletion currents that significantly limit its ability to operate at elevated temperatures relative to HgCdTe. On the other hand, the barrier layer photoconductor offers the capability of flat-band absorber operation, thus, avoiding the depletion current issue; however, the effect of the short S-R lifetime is then reflected in the magnitude of its diffusion current. The merits and limitations of these two architectures will be discussed in this chapter.
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