The problem of quantum efficiency hysteresis (QEH) due to back-side charge accumulation has been reviewed in detail by Griffiths, et al. (1989), and Janesick and Elliot (1991). QEH is not present in the Loral CCDs, because they are front-side illuminated and incorporate MPP operation. This has been verified in component tests at JPL. The absence of QEH means that the devices do not need to be UV-flooded, and so decontamination procedures are planned without the constraint of maintaining the UV-flood.
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