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All of these requirements basically push HgCdTe into extreme modes of operation for currently available devices, in which all the warts of the material and processing are exposed. Dark currents must be reduced, dramatically in some cases, requiring a quantum jump in material performance, together with the introduction of innovative detector architectures. The discussion of the HOT detector requirements in Chapter 6 indicates the required path, namely a reduction in the defect and impurity concentrations in starting materials, together with lower extrinsic doping concentrations. This chapter expands the HOT detector discussion to address detector architectures that, if properly implemented, could meet all of the above IRFPA requirements. We will begin with a discussion of the dark current components on both sides of a standard HgCdTe homo-junction photodiode, with a view to optimizing the diode architecture for specific applications. Examples will be given of projected performance for the above applications utilizing HgCdTe. It will become apparent that one particular architecture, above all others, can meet all of the above IRFPA requirements.
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