Methods and system of enhanced near-infrared light absorption of imaging systems using metasurfaces and nanostructures

A pixel for an imaging sensor, comprising:

• a photodetector comprising a first surface, a first sidewall and a second sidewall, the first sidewall and the second sidewall extending into the photodetector in a first direction from the first surface on opposite sides of the photodetector;
• and
• a metasurface on the first surface, the metasurface comprising nanostructures that bend Near Infrared (NIR) radiation in a predetermined range of wavelengths at an angle of at least 70 degrees from a direction that is substantially perpendicular to the first surface toward the first sidewall and at least 70 degrees from the direction that is substantially perpendicular to the first surface toward the second sidewall,
• wherein the metasurface is within the first and second sidewalls and receives the NIR radiation through a microlens on the metasurface, and
• wherein the first and second sidewalls are reflecting to create spatially localized resonances of a target wavelength that lengthens a path of the NIR radiation.