Integrated colour detectors in 0.18m CMOS technology

Demonstrated is a method for improving the spectral sensitivity of photodetectors using a commercial 0.18m silicon CMOS technology that combines buried double junction photodetectors and metallic grids above the detectors. Spectral sensitivity was measured using the ratio of the output photocurrent generated from different layers, and compared for detectors with and without metal gratings. Enhanced sensitivity was demonstrated by the combination of the buried double junction detectors and metallic grids, this being the first time this has been reported using only a commercial CMOS process.