Advanced Color Filter Isolation Technology for Sub-Micron Pixel of CMOS Image Sensor

In this work, novel color filter isolation technology, which adopts air, the lowest refractive index material on the earth, as a major component of an optical grid structure for submicron pixels of a CMOS image sensor, is presented. Metal in a conventional metal grid structure, which has been widely used for mobile CMOS image sensors, was replaced by the air. The image quality improvement was verified through the enhanced optical performance of the air-grid-assisted pixels.