Silicon photodetectors integrated with vertical silicon nitride waveguides as image sensor pixels: Fabrication and characterization

Abstract

The current trend toward image sensors with ever-increasing pixel counts is prompting continual reductions in pixel area, leading to significant cross-talk and efficiency challenges. The realization of image sensor pixels containing waveguides presents a means for addressing these issues. The fabrication of such pixels is however not straightforward. Conventional waveguides employed in integrated optics are horizontal, but waveguides needed for the proposed sensor must be vertical and integrated with photodetectors. Here, the authors describe a fabrication process for vertical silicon nitride waveguides integrated with silicon photodetectors. The authors describe the etching, deposition, and..