Backside illuminated CMOS image sensors optimized by modeling and simulation

摘要

Design and optimization of back-side illuminated (BSI) CMOS active pixel sensors (APS) using modeling and simulation are presented. To obtain an effective architecture, various device-physics models were developed and CAD simulation tools employed. Subsequently the imagers were successfully designed, fabricated and tested. The imagers exhibit excellent performance regarding many sensor parameters. Optimization exercises intended to further improve the performance matrix have also been deliberated in detail. Three critical aspects have been covered in the paper: the epitaxial layer; pixel isolating deep trenches; and isolation structures (LOCOS).