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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.