Nanowire structured photodiode with a surrounding epitaxially grown P or N layer
View Patent ↗A first exemplary device has a substrate, a nanowire and a doped epitaxial layer surrounding the nanowire. The nanowire is configured to be both a channel to transmit wavelengths up to a selective wavelength. The first exemplary device may further have an active element to detect the wavelengths up to the selective wavelength transmitted through the nanowire. A second exemplary device has a substrate, a nanowire and one or more photogates surrounding the nanowire. The nanowire is configured to be both a channel to transmit wavelengths up to a selective wavelength. The second exemplary device may have an active element to detect the wavelengths up to the selective wavelength transmitted through the nanowire. The one or more photogates comprise an epitaxial layer.
1. A device comprising a substrate, a nanowire and a doped layer surrounding the nanowire, wherein the nanowire is configured to be both a channel to transmit light with wavelengths up to a selective wavelength and an active element to detect light with the wavelengths up to the selective wavelength transmitted through the nanowire; wherein the selective wavelength is an infrared wavelength.
2. The device of claim 1 , wherein the doped layer surrounds a part of or all of the nanowire.
3. The device of claim 1 , further comprising a metal-containing layer surrounding the doped layer.
4. The device of claim 3 , wherein the metal-containing layer is configured to confine light within the metal-containing layer and function as an electronic component.
5. The device of claim 3 , wherein the metal-containing layer is configured to confine light within the metal-containing layer and not function as an electronic component.
6. The device of claim 1 , further comprising a dielectric layer surrounding the doped layer.
7. The device of claim 1 , wherein the doped layer is an epitaxial layer on the nanowire.
8. The device of claim 1 , wherein the substrate has a front side and a back-side, the nanowire disposed on the back-side and an image sensing circuit disposed on the front side.
9. The device of claim 1 , wherein the substrate has a front side and a back-side, wherein both the nanowire and an image sensing circuit are disposed on the front side.
10. The device of claim 1 , wherein the nanowire is not transparent.
11. The device of claim 1 , wherein the device does not include a color or infra-red filter.
12. The device of claim 1 , wherein the nanowire comprises a semiconductor.
13. The device of claim 1 , further comprising a lens structure or an optical coupler over the nanowire, wherein the lens structure or the optical coupler is operably coupled to the nanowire.
14. The device of claim 1 , further comprising an anti-reflective layer disposed on the substrate.
15. The device of claim 1 , wherein the device is an image sensor.
16. The device of claim 1 , wherein the selective wavelength is a function of the diameter of the nanowire.
17. The device of claim 1 , wherein the nanowire comprises a PN or PIN junction.
18. The device of claim 1 , wherein the doped layer is p-doped.
19. The device of claim 1 , wherein the doped layer is n-doped.
20. The device of claim 1 , wherein the nanowire is doped or undoped.
21. The device of claim 1 , further comprising one or more photogates surrounding the nanowire.
22. The device of claim 21 , further comprising a dielectric layer between the nanowire and the one or more photogates.
23. The device of claim 21 , wherein the substrate has a front side and a back-side, the nanowire disposed on the back-side and an image sensing circuit disposed on the front side.
24. The device of claim 21 , wherein the substrate has a front side and a back-side, wherein both the nanowire and an image sensing circuit are disposed on the front side.
25. The device of claim 21 , wherein the device does not include a color or infra-red filter.
26. The device of claim 21 , further comprising an anti-reflective layer disposed on the substrate.
27. The device of claim 21 , wherein the device is an image sensor.
28. The device of claim 21 , wherein the selective wavelength is a function of the diameter of the nanowire.
29. The device of claim 21 , further comprising photodiode disposed in or on the substrate.
30. The device of claim 21 , the one more photogates comprises a first photogate configured to be a switch and a second photogate configured to control a potential in the nanowire.
31. The device of claim 21 , wherein the one or more photogates comprises an epitaxial metal or metal oxide layer.
32. The device of claim 1 , wherein the nanowire is an upstanding nanowire protruding from the substrate.
33. The device of claim 1 , further comprising a reflective layer disposed on the substrate.
34. The device of claim 33 , wherein the reflective layer is configured to reflect light transmitted by the nanowire.
35. The device of claim 33 , wherein the reflective layer comprises a multilayered structure comprising repeated layers of silicates.
36. The device of claim 33 , wherein the reflective layer comprises a metal film.
37. The device of claim 1 , wherein the nanowire has a diameter of 100 nm or more.
38. The device of claim 1 , wherein the nanowire comprises GaAs.
39. The device of claim 15 , wherein the image sensor is configured to detect infrared.
40. The device of claim 1 , further comprising a filter that essentially cuts off visible light and passes infrared light.