Delta-doped CCDS, developed at JPL’s Microdcvices Laboratory, have achicvcd stable 100% internal quantum efficiency in the visible and near UV regions of the spectrum. In this approach, an cpitaxial silicon layer is grown on a fully-processed commercial CCD using molecular beam epitaxy. During the silicon growth on the CCD, 30% of a monolayer of boron atoms are deposited on the surface, followed by a 15 ~ silicon layer for surface passivation. The boron is nominally incorporated within a single atomic layer at the back surface of the device, resulting in the effective elimination of the backside potential well. The measured quantum efficiency is in good agrccmcnt with the theoretical limit imposed by reflection from the Si surfiace. Enhancement of the total quantum efficiency in the blue visible and near [JV has been demonstrated by depositing antircflcction coatings on the delta-doped CCD. Recent results on antircflcction coatings and quantum efficiency measurements are discussed.
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