Patent attributes
An image sensor includes a photodiode disposed in semiconductor material to accumulate image charge in response to light directed through a back side of the semiconductor material. A scattering structure is disposed proximate to the front side of the semiconductor material such that the light that is directed into the semiconductor material through the back side is scattered back through the photodiode. A deep trench isolation structure is disposed in the semiconductor material that isolates the photodiode and defines an optical path such that the light that is scattered back through the photodiode in the optical path is totally internally reflected by the DTI. An antireflective coating is disposed on the back side of the semiconductor material and totally internally reflects the light scattered by the scattering structure to confine the light to remain in the optical path until it is absorbed.