Nanowire sized opto-electronic structure and method for manufacturing the same
An opto-electric structure includes a plurality of nano elements arranged side by side on a support layer, where each nano element includes at least a first conductivity type semiconductor nano sized core, and where the core and a second conductivity type semiconductor form a pn or pin junction. A first electrode layer that extends over the plurality of nano elements and is in electrical contact with at least a portion of the second conductivity type semiconductor, and a mirror provided on a second conductivity type semiconductor side of the structure.
1. An opto-electric structure, comprising:
a plurality of nano elements arranged side by side on a support layer, wherein each nano element comprises at least a first conductivity type semiconductor nano sized core, wherein the core and a second conductivity type semiconductor form a pn or pin junction;
a first electrode layer that comprises a conductive material and extends over the plurality of nano elements and is in electrical contact with at least a portion of the second conductivity type semiconductor wherein the first electrode layer forms an air bridge such that an empty space is located between the support layer, adjacent nano elements and the first electrode layer; and
a material layer overlying the first electrode layer and contacting the first electrode layer.
2. The structure of claim 1 , further comprising a mirror provided on a second conductivity type semiconductor side of the structure.
3. The structure of claim 2 , wherein the mirror is provided as a reflective material layer on the first electrode layer.
4. The structure of claim 3 , further comprising a second electrode layer which electrically connects to the nano sized cores.
5. The structure of claim 4 , further comprising a diffusion barrier layer over the mirror.
6. The structure of claim 5 , further comprising a eutectic bonding layer over the diffusion barrier layer.
7. The structure of claim 6 , further comprising a transparent insulating layer over the first electrode, wherein the transparent insulating layer providing a planar surface for the mirror and the mirror electrically contacting the first electrode layer through an opening in the transparent insulating layer.
8. The structure of claim 7 , wherein the structure is flip-chip bonded onto contact electrodes on a carrier using the eutectic bonding layer, and wherein a first portion of the carrier is electrically connected to the first electrode layer by the eutectic bonding layer, the diffusion barrier layer and the mirror, and a second portion of the carrier is connected to the second electrode layer by a wire.
9. The structure of claim 3 , wherein the first electrode layer is transparent.
10. The structure of claim 3 , wherein the thickness of the first electrode layer is 150 nm-900 nm.
11. The structure of claim 3 , wherein the second conductivity type semiconductor comprises a semiconductor shell which is part of the nano element, and each nano element comprises a nanostructure containing the core, the shell and an active region between the core and the shell.
12. The structure of claim 3 , wherein: the second conductivity type semiconductor comprises a bulk semiconductor element that is not part of the nano element; the core comprises a semiconductor nanowire of the first conductivity type or the semiconductor nanowire of the first conductivity type and at least one semiconductor shell of the first conductivity type; and each nano element comprises a nanostructure containing the core, and an active region between the core and the bulk semiconductor element.
13. The structure of claim 2 , wherein the first electrode layer is reflective and comprises the mirror.
14. The structure of claim 1 , wherein the first electrode has a tapered decrease in thickness from each tip of the nano elements towards a respective base of the nano elements.
15. The structure of claim 1 , further comprising a second plurality of nano elements arranged side by side on the support layer and laterally spaced from the plurality of nano elements, wherein second plurality of nano elements is not covered by the first electrode layer or any other layer comprising a same material as the first electrode layer.
16. The structure of claim 1 , wherein the first electrode layer is reflective.
17. The structure of claim 1 , further comprising a second plurality of nano elements arranged side by side on the support layer and laterally spaced from the plurality of nano elements, wherein the material layer contacts surfaces of the second plurality of nano elements.
18. The structure of claim 17 , wherein second plurality of nano elements is not covered by the first electrode layer or any other layer comprising a same material as the first electrode layer.