A new process for thinned, back-illuminated CCD imager devices

Abstract
A manufacturable process for converting a front-illuminated CCD imager to its back-illuminated counterpart is described. Low-light-level imaging is enhanced, especially in the blue and deep-ultraviolet region. Quantum efficiency is significantly improved by forming a shallow p/sup +/ accumulation layer on the back surface using a laser-induced activation of very-low-energy boron implantation. The fabrication process has been applied to 64-*128-, 420-*420-, and 420-*840-pixel imagers. An example of imaging obtained with the 420-*420-pixel imager is shown and discussed. Experimental results showing the enhanced response of the 64-*128-pixel imager are presented.