A large format backside illuminated CCD has been developed by THOMSON TCS. This thinned CCD is mainly dedicated to scientific imaging field where high sensitivity and low noise operation are required. This product was designed specifically for the Very Large Telescope optical instruments needs, and supported by ESO organization. The imaging area is a 2 k X 2 k 15 micrometers square pixel array, with 100% optical aperture, arranged in a full frame organization. Charge transfer operates in the four phase mode, and thus provide large handling capability in MPP mode. This device offers two low noise output ports that reach typically 4 e- rms noise in slow scan operation (at 50 kHz typical data rate) at -40 degree(s)C. Thanks to THOMSON 1.5 micrometers technology, and to its wafer thinning technology, this device features a very high quantum efficiency over a wide spectrum range (typically 80% peak quantum efficiency). Its specific thinning and assembly processes make it suitable for construction of 2 X N CCD mosaic (three sides are buttable), with less than 400 micrometers dead gap between sensitive areas and good flatness performance (typically 15 micrometers peak to peak is achieved). Electro-optical characterization results are described in this paper as well as the specific assembly process and butting technique.
"2k x 2k three side buttable thinned CCD", Proc. SPIE 2654, Solid State Sensor Arrays and CCD Cameras, (25 March 1996); doi: 10.1117/12.236087; https://doi.org/10.1117/12.236087