WORKSHOP PAPER
Improved QE in CMOS image sensors with nano-black antireflection layer
Abstract
A novel anti-reflection process is demonstrated which improves the quantum efficiency (QE) of a CMOS image sensor, with particular benefits at the ultraviolet (UV) and near infrared (NIR) ends of the electromagnetic spectrum. Additionally, the dark current and photoresponse non-uniformity (PRNU) were reduced to about 33% and 55%, respectively, of the values for a conventional control sensor. The nano-black anti-reflection layer was made using a reactive-ion-etch technique to form nano-scale spikes at the surface which greatly reduce the reflectivity of the surface, which has a matt-black appearance.Keywords
image sensor, CMOS, quantum efficiency, antireflection coating,References
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