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We discussed (with Barry Burke) the range of detector designs that the MIT Lincoln Labs were producing. They appear to have a very advanced fabrication facility which allows them to produce devices which are cosmetically very good, are of low noise and back-thinned. Table 6 below summarises the characteristics of their current large format imagers.
They have made devices with pixels;
and
frame sizes both 3-edge buttable. The
read-out noise quoted for the CCID-10 device was
at a pixel rate of 1MHz.
The same performance is expected of the CCID-16. All devices are back-thinned;
they have also been improving the annealing process for optimum UV response.
Some response curves which we saw indicated that their surface treatment
may enable a QE of
to be achieved over the wavelength
range 2000-4000
.
Newest in the production phase is a pixel device (CCID-16)
with
pixels. These devices have tapered serial
registers to permit the minimum dead space when butting. The array comes
on a package with
photometers. The
anticipated frame-rate of this imager is
,
operating in frame transfer mode.
Further discussions took place with Robert Reich who demonstrated the
MIT/LL adaptive optics system. This currently uses a array which
can be read at 2000
and has a noise floor of
at
1MHz (
at 2.78MHz). The detector is run at
. The
devices are back-illuminated with a gain response of
.
The system is operated from a PC so that they can implement focusing
by storing 100,
frames in a frame buffer.
They have also developed a novel buried shutter which operates very
fast and allows the
charge collection area to be isolated whilst the CCD is being read-out.
This facility takes up some silicon and so the full-well is less than
that on standard devices; the shutter is also only effective at
.
They are also working on a system which will utilise pixel
devices for Fugate at the USAF.
As the Lincoln Lab. is federally funded, they appear to have difficulties selling devices commercially to anyone, particularly outside the USA. Various discussions have taken place since then and we are investigating possible routes to obtain such devices.