Color filter array, imagers and systems having same, and methods of fabrication and use thereof
View Patent ↗A pixel cell with a photosensitive region formed in association with a substrate, a color filter formed over the photosensitive region, the color filter comprising a first material layer and a second material layer formed in association with the first shaping material layer.
1. A method of manufacturing an imager, the method comprising:
providing a pixel cell array formed in a substrate, the pixel cell array having an array of at least first, second, and third photosensors; and
forming a color filter array over the pixel cell array based at least in part on:
patterning at least first, second, and third base materials respectively over the first, second, and third photosensors;
depositing a first conforming layer adjacent to the first base material and between the first base material and the second base material, or between the first base material and the third base material, or both;
depositing a second conforming layer adjacent to the second base material and between the second base material and the first base material or between the second base material and the third base material, or both;
depositing a third conforming layer adjacent to the third base material and between the third base material and the first base material or between the third base material and the second base material, or both; and
forming first, second, and third microlenses respectively over the first, second, and base materials.
2. The method of manufacturing of claim 1 , wherein depositing each of the first conforming layer, the second conforming layer, and the third conforming layer includes using corresponding one of the first, second, or third base materials as a barrier to contain conformal material of the first conforming layer, the second conforming layer, and the third conforming layer.
3. The method of manufacturing of claim 1 , wherein depositing each of the first conforming layer, the second conforming layer, and the third conforming layer includes depositing a conformal material having a refractive index that focuses incoming light of a targeted wavelength onto a focal plane of a corresponding one of the first, second and third photosensors.
4. The method of manufacturing of claim 1 , wherein each of the first conforming layer, the second conforming layer, the third conforming layer, or any combination thereof, has a shape defined at least partially by at least one of the first, second, or third base materials.
5. The method of manufacturing of claim 1 , wherein patterning at least the first, second, and third base materials over the first, second, and third photosensors comprises:
forming one or more base material precursors over the first, second, and third photosensors; and
exposing the one or more base material precursors to ultraviolet light, wherein patterning at least the first, second, and third base materials is based at least in part on exposing the one or more base material precursors to the ultraviolet light.
6. The method of manufacturing of claim 5 , further comprising:
masking the one or more base material precursors prior to exposing the one or more base material precursors to the ultraviolet light; and
removing one or more portions of the one or more base material precursors after exposing the one or more base material precursors to the ultraviolet light.
7. The method of manufacturing of claim 6 , wherein the one or more base material precursors comprise a negative photoresist material, and wherein the removed one or more portions comprise portions of the one or more base material precursors that are prevented from exposure to the ultraviolet light based at least in part on the masking.
8. The method of manufacturing of claim 6 , wherein the one or more base material precursors comprise a positive photoresist material, and wherein the removed one or more portions comprise portions of the one or more base material precursors that are exposed to the ultraviolet light based at least in part on the masking.
9. The method of manufacturing of claim 1 , further comprising:
depositing a passivation layer over the pixel cell array, wherein the first, second and third base materials and the first conformal layer, the second conformal layer, and the third conformal layer directly contact a top surface of the passivation layer.
10. The method of manufacturing of claim 1 , further comprising:
forming respective microlenses over each of the first, second, and third base materials.
11. The method of manufacturing of claim 1 , wherein the first, second and third base materials and the first conformal layer, the second conformal layer, and the third conformal layer form a substantially gapless and coextensive cover layer over the first, second and third photosensors.
12. The method of manufacturing of claim 1 , wherein the first conforming layer, the second conforming layer, and the third conforming layer comprises a same material as at least one of the first, second, or third base materials.
13. The method of manufacturing of claim 1 , wherein a height of the first conforming layer, the second conforming layer, the third conforming layer, or any combination thereof, is substantially the same as a height of one or more of the first, second, or third base materials.
14. The method of manufacturing of claim 1 , wherein the first, second, and third base materials comprise an optically transparent material.