Apparatus and method for reducing optical cross-talk in image sensors

A method for making an image sensor device, comprising:

• providing a semiconductor substrate having a front surface and a back surface;
• forming a plurality of pixels on the front surface of the semiconductor substrate, each pixel being adapted for sensing light radiation;
• forming an array of color filters over the plurality of pixels, each color filter being adapted for allowing a wavelength of light radiation to reach at least one of the plurality of pixels;
• and
• forming a plurality of micro-lens over the array of color filters, each micro-lens being adapted for directing light radiation to at least one of the color filters in the array;
• wherein the forming the array of color filters further includes forming the array of color filters with a structure adapted for blocking light radiation traveling towards a region between adjacent micro-lens.

A semiconductor device, comprising:

• a substrate having a front surface and a back surface;
• a plurality of pixels formed on the front surface of the substrate, each pixel being adapted to sense light radiation directed towards the back surface of the substrate;
• an array of color filters formed over the back surface of the substrate, each color filter being aligned with one of the plurality of pixels for allowing a wavelength of light radiation to pass through to the one of the plurality of pixels;
• a plurality of micro-lens formed over the array of color filters, each micro-lens being adapted to direct light radiation to each color filter in the array;
• and
• a blocking structure disposed between the back surface of the substrate and the plurality of micro-lens, the blocking structure being adapted to block light radiation traveling towards a region between adjacent micro-lens from reaching the pixels.