Formation of buried color filters in a back side illuminated image sensor with an ONO-like structure

摘要

A semiconductor image sensor includes a substrate having a first side and a second side that is opposite the first side. An interconnect structure is disposed over the first side of the substrate. A plurality of radiation-sensing regions is located in the substrate. The radiation-sensing regions are configured to sense radiation that enters the substrate from the second side. A plurality of light-blocking structures is disposed over the second side of the substrate. A passivation layer is coated on top surfaces and sidewalls of each of the light-blocking structures. A plurality of spacers is disposed on portions of the passivation layer coated on the sidewalls of the light-blocking structures.

主权项

1. A method of fabricating a semiconductor image sensor device, comprising:
bonding a first side of a device substrate to a carrier substrate, the device substrate including a pixel region and a bonding pad region, wherein the pixel region contains a plurality of light-sensing pixels configured to sense radiation that enters the device substrate from a second side opposite the first side; thinning the device substrate from the second side; forming a plurality of light-reflective structures over the second side of the device substrate after the thinning, the light-reflective structures partially defining a plurality of openings; forming a first layer over each of the light-reflective structures; forming a second layer over the first layer, the first layer and the second layer having different material compositions; and filling the openings with a third layer, the third layer and the second layer having different material compositions.