CCD Development Progress at Lawrence Berkeley National Laboratory

摘要

P - channel CCD imagers, 200 - 300 μm thick, fully depleted, and back-illuminated are being developed for scientific applications including ground - and space - based astronomy and x - ray detection. These thick devices have extended IR response, good Point-Spread Function (PSF) and excellent radiation tolerance. Initially, these CCDs were made in-house at LBNL using 100 mm diameter wafers. Fabrication on high-resistivity 150 mm wafers is now proceeding according to a model in which the wafers are first processed at DALSA Semiconductor up to the Al contact mask step. They are then thinned and the remaining processing is done in small batches at LBNL. Alternative approaches are also discussed. In addition we have implemented designs that permit high - voltage biasing to further improve the PSF. With these designs, operation of 200 μm thick CCDs at 100 V or more bias with excellent PSF is practical.