Image sensor and method of manufacturing the same

An image sensor, comprising:

• a semiconductor substrate comprising a first photodiode and a second photodiode;
• a pillar array layer disposed on the semiconductor substrate, the pillar array layer comprising a first pillar array disposed above the first photodiode and a second pillar array disposed above the second photodiode,
• wherein the first pillar array comprises a plurality of first pillar structures, the second pillar array comprises a plurality of second pillar structures, all the first pillar structures have a first height, all the second pillar structures have a second height, and the pillar array layer satisfies the following conditions:
• a shape of each of the first pillar structure is different from a shape of each of the second pillar structure, wherein the shape of a top planar surface of each of the first pillar structure is a rectangle, circle, square, or ellipse shape from a top view, and the shape of a top planar surface of each of the second pillar structure is a rectangle, circle, square, or ellipse shape from a top view;
• a planar layer disposed on the pillar array layer;
• and
• a microlens layer disposed on the planar layer, wherein a refractive index of the microlens layer is less than a refractive index of the planar layer, the refractive index of the planar layer is less than a refractive index of the pillar array layer, and the refractive index of the pillar array layer is less than a refractive index of the semiconductor substrate.