Image sensor having micro-lenses with integrated color filter and method of making
An image sensor comprising a plurality of pixels formed in a semiconductor substrate, each pixel including a light sensitive element, and a color filter material formed over the light sensitive element, the color filter material formed in a micro-lens shape.
1. A method of forming a pixel of an image sensor comprising:
forming a light sensitive element in a semiconductor substrate;
forming a color filter material over said light sensitive element;
forming a spherical drop over said color filter material and over said light sensitive element, said spherical drop formed from a sacrificial material; and
etching said color filter material using said spherical drop as a mask, such that said color filter material mimics the shape of said spherical drop after etching and becomes a micro-lens shape.
2. The method of claim 1 wherein said color filter material is selected from the group of red color filter material, green color filter material, and blue color filter material.
3. The method of claim 1 further including a color filter material is selected from the group of cyan color filter material, yellow color filter material, and magenta color filter material.
4. The method of claim 1 wherein the color filter material is pigmented or dyed polymethylmethacrylate (PMMA) or polyglycidylmethacrylate (PGMA).
5. The method of claim 1 further including forming a passivation layer over said color filter material.
6. The method of claim 5 wherein said passivation layer has a molecular number of between 50,000 and 200,000.