Nanowire structured color filter arrays and fabrication method of the same

1. A method of making a color filter array, the method comprising:

making nanowires, wherein each of the nanowires extend substantially perpendicularly from a substrate;

disposing a transparent polymer to substantially encapsulate the nanowires;

removing the nanowires from the substrate; providing a pixel array comprising a plurality of pixels, wherein a hard polymer substantially covers an image plane of the pixel array;

disposing the nanowires on the pixel array; and

removing the transparent polymer encapsulating the nanowires;

wherein making the nanowires comprises generating an array of dots in a resist layer on the substrate and forming the nanowires by etching the substrate, wherein shapes and sizes of the dots determine the cross-sectional shapes and sizes of the nanowires.

2. The method of claim 1 , wherein the pixel array comprises an image sensor including a charge-coupled device (CCD) array or a complementary metal-oxide-semiconductor (CMOS) sensor array.

3. The method of claim 1 , wherein the nanowires are arranged in an array having substantially a same shape and pitch as that of the pixel array.

4. The method of claim 1 , wherein generating the array of dots comprises using a lithography technique.

5. The method of claim 1 , wherein the etching is dry etching.

6. The method of claim 1 , wherein the transparent polymer comprises polydimethyl siloxane (PDMS), or polymethyl methacralate (PMMA).

7. The method of claim 1 , wherein disposing the transparent polymer comprises depositing the transparent polymer by spraying or pouring.

8. The method of claim 1 , wherein removing the nanowires from the substrate comprises wet etching the substrate, removing the substrate using chemical mechanical polishing or mechanically detaching the nanowire array from the substrate by scrapping or undercutting the nanowire array.

9. The method of claim 1 , wherein disposing the nanowires on the pixel array comprises:

removing at least a portion of the transparent polymer material such that at least a portion of the nanowires is not encapsulated;

disposing the hard polymer such that the hard polymer encapsulates at least a portion of nanowires not encapsulated by the transparent polymer;

aligning the nanowires on the pixel array such that the hard polymer encapsulating the nanowires is in contact with the hard polymer disposed on the pixel array, wherein each of the plurality of pixels is aligned with one or more nanowires; and

melting the hard polymer such that the nanowires fuses with the pixel array.

10. The method of claim 1 , further comprising disposing a material having a lower refractive index than a material of the nanowires such that the material having the lower refractive index than the material of the nanowires substantially fills a space between the nanowires.

11. The method of claim 10 , wherein the material having the lower refractive index than the material of the nanowires is disposed using chemical vapor deposition or atomic layer deposition.

12. The method of claim 10 , further comprising disposing a plurality of optical couplers such that each of the plurality of optical couplers is associated with at least one nanowire.

13. The method of claim 12 , wherein the plurality of optical couplers are configured to guide radiation into the nanowires.

14. The method of claim 1 , wherein the nanowires comprise one or more of silicon (Si), germanium (Ge), boron phosphide (BP), boron arsenide (BAs), aluminum phosphide (AlP), aluminum arsenide (AlAs), aluminum antimonide (AlSb), gallium nitride (GaN), gallium phosphide (GaP), gallium arsenide (GaAs), gallium antimonide (GaSb), indium nitride (InN), indium phosphide (InP), indium arsenide (InAs), zinc oxide (ZnO), zinc sulfide (ZnS), zinc selenide (ZnSe), zinc telluride (ZnTe), cadmium sulfide (CdS), cadmium selenide (CdSe), and cadmium telluride (CdTe).