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In the 3-centre effort to produce large format thinned CCDs, Dick Bredthauer is the 3rd party we visited, John Geary (SAO) and Mike Lesser (Steward) being the other two. The Loral - Newport Beach operation currently produces (and larger) devices, marketed as a batch of 4-inch wafers. The wafer runs take approximately 3 months to complete and they were about to produce a demonstration device by the end-of-July. Bredthauer designs some devices as well as John Geary and others.
The Geary designs have been discussed already. Other recent (Loral) designs include a University of Hawaii device and an ESO , custom imager (ESO, Oct. '93).
The main problem we could see with the operation was that was no real way of knowing what the low-light level performance of the wafers was likely to be until after the devices had been thinned and packaged by Mike Lesser. This rather unacceptable situation may be changing now (Fri Sep 9 14:56:26 BST 1994 ) with the possibility that Mike Lesser will be able to wafer test the devices at cryogenic temperatures and under slow-scan, low-light level conditions in about 6 months.
Some batches have resulted in devices which suffer from low-level charge traps; this being attributable to poor quality silicon wafers. It is hoped that careful control will prevent future occurances - but foundry runs, by their very nature, come with no guarantees.