Method, apparatus and system providing imaging device with color filter array
A method and apparatus that provide a color filter array for use in an imaging device and/or system. The color filter array contains a stopping layer located at least on selected color filters. The stopping layer allows a planarization process step, such as a chemical mechanical planarization process step, to be carried out during the formation of the color filter array. The color filter array so formed can have a planarized surface thereon so that microlenses and/or passivation and oxide layer(s) can be directly formed on such planarized surface of the color filter array.
1 . A color filter array comprising:
a plurality of color filters formed over an underlying structure; and
a stopping layer formed on at least one first color filter and extending to at least partially cover a side wall of the first color filter.
2 . The color filter array of claim 1 further comprising a planarized surface level with the stopping layer.
3 . The color filter array of claim 1 , wherein the stopping layer comprises:
a plurality of stopping sections formed on a plurality of first color filters; and
a plurality of transverse sections each extending transversely from one of the stopping sections, the transverse sections substantially covering side walls of the plurality of first color filters.
4 . The color filter array of claim 3 , wherein at least one of the transverse sections extends at least partially between the first color filter and its adjacent color filter.
5 . The color filter array of claim 3 , wherein the transverse sections entirely cover side walls of each of the first color filters.
6 . The color filter array of claim 3 , wherein the stopping layer further comprises a plurality of lower sections each extending from one of the transverse sections and located below a second color filter.
7 . The color filter array of claim 6 , wherein the stopping layer is continuous.
8 . The color filter array of claim 6 , wherein the stopping layer is an integral layer.
9 . The color filter array of claim 1 , wherein the stopping layer is formed to be more resistant to a chemical mechanical planarization process than other color filters.
10 . The color filter array of claim 1 , wherein the stopping layer comprises a material that is more resistant to a planarization process than a material used for second color filters.
11 . The color filter array of claim 1 , wherein the stopping layer is formed of a material selected from the group consisting of an oxide material, a silicon nitride material, and a mixture thereof.
12 . The color filter array of claim 11 , wherein the stopping layer is formed of an oxide material.
13 . The color filter array of claim 11 , wherein the stopping layer is formed of a silicon oxynitride material.
14 . The color filter array of claim 11 , wherein the stopping layer is a dielectric antireflective coating.
15 . The color filter array of claim 1 , wherein the stopping layer has a substantially uniform thickness throughout the color filter array.
16 . The color filter array of claim 1 , wherein the stopping layer has a thickness up to about 1000 Angstroms.
17 . The color filter array of claim 1 , wherein the stopping layer has a thickness up to about 300 Angstroms.
18 . The color filter array of claim 17 , wherein the stopping layer has a thickness of about 100 Angstroms or more.
19 . The color filter array of claim 17 , wherein the stopping layer has a thickness in the range from about 100 Angstroms to about 300 Angstroms.
20 . The color filter array of claim 3 , wherein the transverse sections have a lesser lateral thickness than the thickness of the stopping sections.
21 . An imaging device comprising:
a semiconductor structure; and
a color filter array formed over the semiconductor structure, the color filter array comprising at least one first color filter and a stopping layer formed on the first color filter;
wherein the color filter array comprises a planarized surface level with the stopping layer.
22 . The imaging device of claim 21 , wherein the stopping layer extends transversely to at least partially cover one or more side walls of the first color filter.
23 . The imaging device of claim 21 , wherein the stopping layer comprises:
a plurality of stopping sections formed on a plurality of first color filters; and
a plurality of transverse sections each extending transversely from one of the stopping sections, the transverse sections substantially covering side walls of the plurality of first color filters.
24 . The imaging device of claim 23 , wherein at least one of the transverse sections extends at least partially between the first color filter and its adjacent color filter.
25 . The imaging device of claim 23 , wherein the transverse sections entirely cover side walls of each of the first color filters.
26 . The imaging device of claim 23 , wherein the stopping layer further comprises a plurality of lower sections each extending from one of the transverse sections and located below a second color filter.
27 . The imaging device of claim 21 , wherein the stopping layer is formed to be more resistant to a chemical mechanical planarization process than second color filters.
28 . The imaging device of claim 21 , wherein the stopping layer is formed of a material selected from the group consisting of an oxide material, a silicon nitride material, and a mixture thereof.
29 . The imaging device of claim 21 , wherein the stopping layer has a substantially uniform thickness throughout the color filter array.
30 . The imaging device of claim 21 , wherein said imaging device is coupled to a processor of a processing system.
31 . An imaging device comprising:
a color filter array formed over a semiconductor structure and comprising red, green, and blue filters; and
a continuous stopping layer formed on the green color filters;
wherein the stopping layer continuously extends between each green color filter and its adjacent red and blue filters and below the red and blue filters.
32 . The imaging device of claim 31 , wherein the red and blue color filters collectively comprise a planarized surface level with the stopping layer.
33 . The imaging device of claim 31 , wherein the red, green, and blue filters are arranged according to a Bayer filter pattern.
34 . The imaging device of claim 31 , wherein the stopping layer has a substantially uniform thickness throughout the color filter array.
35 . The imaging device of claim 31 , wherein the stopping layer has a thickness of no less than 100 Angstroms.
36 . The imaging device of claim 35 , wherein the stopping layer has a thickness in the range from about 100 Angstroms to about 300 Angstroms.
37 . The imaging device of claim 31 , wherein the stopping layer is formed of a material that is more resistant to a chemical mechanical planarization process than a material used for the red and blue filters.
38 . The imaging device of claim 37 , wherein the stopping layer is formed of an oxide material.
39 . An imaging system comprising:
a pixel array;
a color filter array formed over the pixel array and including a plurality of color filters for different colors;
a stopping layer formed on at least one first color filter and extending to cover one or more side walls of the first color filter; and
a circuit coupled to the pixel array for using pixel signals from the pixel array and converting the pixel signals to image data.
40 . The imaging system of claim 39 , wherein the color filter array comprises a planarized surface level with the stopping layer.
41 . The imaging system of claim 39 , wherein the stopping layer comprises:
a plurality of stopping sections formed on a plurality of first color filters; and
a plurality of transverse sections each extending transversely from one of the stopping sections, the transverse sections substantially covering side walls of the plurality of first color filters.
42 . The imaging system of claim 41 , wherein the stopping layer further comprises a plurality of lower sections each extending from one of the transverse sections and located below a second color filter.
43 . The imaging system of claim 42 , wherein the stopping layer is continuous.
44 . An imaging system comprising:
a pixel array;
a color filter array formed over the pixel array and of a plurality of first and second color filters;
a stopping layer formed on the first color filters; and
a circuit coupled to the pixel array for using pixel signals from the pixel array and converting the pixel signals to image data;
wherein the color filter array comprises a planarized surface formed on the second color filters and level with the stopping layer.
45 . The imaging system of claim 44 , wherein the stopping layer extends to at least partially cover one or more side walls of the first color filters.
46 . The imaging system of claim 44 , wherein the stopping layer comprises:
a plurality of stopping sections formed on the first color filters; and
a plurality of transverse sections each extending transversely from the stopping sections and between a first color filter and an adjacent second color filter.
47 . The imaging system of claim 46 , wherein the stopping layer further comprises a plurality of lower sections extending from one of the transverse sections and located below a second color filter.
48 . The imaging system of claim 47 , wherein the stopping layer is continuous.
49 . A method of forming a color filter array, the method comprising:
forming a plurality of first color filters over an underlying structure;
forming a stopping layer over the first color filters; and
forming additional color filters in the color filter array in areas not occupied by the first color filters.
50 . The method of claim 49 further comprising forming a planarized surface on the color filter array, wherein the planarized surface is level with the stopping layer.
51 . The method of claim 49 , wherein the step of forming a stopping layer comprises forming a continuous layer substantially covering side walls of the first color filters.
52 . The method of claim 49 , wherein the stopping layer is formed to have a uniform thickness across the color filter array.
53 . The method of claim 49 , wherein the step of forming a stopping layer is carried out at a temperature of about 240° C. or less.
54 . The method of claim 49 , wherein the step of forming a stopping layer comprises:
forming a plurality of stopping sections on the first color filters; and
forming a plurality of transverse sections each extending transversely from one of the stopping sections and at least partially covering a side wall of one of the first color filters.
55 . The method of claim 54 , wherein the transverse sections have a lesser lateral thickness than the thickness of the stopping sections.
56 . The method of claim 54 , wherein the step of forming a stopping layer comprises forming a plurality of lower sections each continuously extending from one of the transverse sections and being located under an additional color filter.
57 . The method of claim 49 , wherein the step of forming the additional color filters comprises providing one or more additional filter material layers and planarizing the additional filter material layers by a planarization process.
58 . The method of claim 57 , wherein the stopping layer is used to stop the planarization process.
59 . The method of claim 57 , wherein the planarization process is a chemical mechanical planarization process.
60 . A method of forming an imaging device comprising a color filter array including red, green, and blue filters, the method comprising:
providing a semiconductor structure comprising a pixel array;
forming a plurality of green filters over the semiconductor structure;
forming a continuous stopping layer on the green filters; and
forming red and blue filters in the color filter array over the stopping layer.
61 . The method of claim 60 , wherein the step of forming red and blue filters comprises using a chemical mechanical planarization process.
62 . The method of claim 60 , wherein the step of forming red and blue filters comprises depositing a blue filter material layer over the stopping layer and planarizing the blue filter material layer to form blue filters.
63 . The method of claim 62 further comprising selectively etching the blue filter material layer to remove blue filter material occupying areas of the red filters.
64 . The method of claim 63 , wherein the step of forming red and blue filters further comprises depositing a red filter material layer over the stopping layer and planarizing the red filter material layer to form red filters.
65 . A method of forming an imaging device comprising a color filter array, the method comprising:
forming a pixel array;
forming a plurality of first color filters over the pixel array;
forming a stopping layer on the first color filters;
providing an additional color filter material layer between the first color filters; and
planarizing the additional color filter material layer to form additional color filters.
66 . The method of claim 65 , wherein the color filter array has a planarized surface level with the stopping layer.
67 . The method of claim 65 further comprising forming a microlens array directly on the planarized surface of the color filter array.
68 . The method of claim 65 , wherein the step of forming a stopping layer comprises forming a continuous layer across the color filter array.
69 . The method of claim 65 , wherein the step of planarizing the additional color filter material layer comprises using a chemical mechanical planarization process to bring the additional color filter material layer to be level with the stopping layer.
70 . The method of claim 69 , wherein the stopping layer is used to stop the chemical mechanical planarization process.