Image sensor having micro-lens array separated with trench structures and method of making
An image sensor having micro-lenses is disclosed. The image sensor comprises a plurality of pixels formed in a semiconductor substrate, each pixel including a light sensitive element. A micro-lens is formed over each of the light sensitive elements. Finally, a trench structure surrounds each of the micro-lenses.
1. An image sensor comprising:
a plurality of pixels formed in a semiconductor substrate, each pixel including a light sensitive element;
a layer formed over said light sensitive elements;
a micro-lens over each of said light sensitive elements and directly atop said layer; and
a trench structure surrounding each of said micro-lens, said trench structure formed in the top of said layer and extending to the interface between said layer and said micro-lens, said trench structure separating said micro-lens from its adjacent micro-lenses, wherein said trench structure is circular.
2. The image sensor of claim 1 wherein the micro-lenss are formed from polymethylmethacrylate (PMMA) or polyglycidylmethacrylate (PGMA).
3. The image sensor of claim 1 wherein said trench structure is formed in a layer that underlies said micro-lenses.
4. The image sensor of claim 1 further including a color filter layer between said micro-lenss and said light sensitive elements.
5. A pixel of an image sensor comprising:
a light sensitive element formed in a semiconductor substrate;
a layer formed over said light sensitive element;
a micro-lens over said light sensitive element and directly atop said layer; and
a trench structure surrounding each of said micro-lens, said trench structure formed in the top of said layer and extending to the interface between said layer and said micro-lens, said trench structure separating said micro-lenses from its adjacent micro-lens, wherein said trench structure is circular.
6. The pixel of claim 5 wherein the micro-lens is formed from polymethylmethacrylate (PMMA) or polyglycidylmethacrylate (PGMA).
7. The pixel of claim 5 wherein said trench structure is formed in the material that underlies said micro-lenses.
8. The pixel of claim 5 further including a color filter layer between said micro-lenss and said light sensitive elements.