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Open
Poly or Open Electrode CCD
The Open Poly or open-electrode CCD is a front illuminated
CCD with a modified electrode structure to enhance the
UV sensitivity. Some of the polysilicon gate structure,
which absorbs UV radiation is removed, leaving a large
part (40%) of the pixel area uncovered.
See
Figure 1.
To
control the surface potential in the open area, a shallow
p+ implant is located in the buried channel. This pins
the local surface potential to that of the substrate.
Thus the device operates in a similar manner to a conventional
front illuminated CCD at a 40% reduced full well capacity.
The QE of the device is increased through the spectral
range and is roughly a factor of 2 times better in the
UV vs. Lumogen coated devices, while exhibiting none
of the etaloning behavior of back illuminated CCD’s
beyond 800 nm. We offer the Spec-10 : 256E 1024 x 256
pixel spectroscopy CCD in open-electrode technologie
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 Figure
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