3-D structure for increasing contact surface area for LEDs
Disclosed herein is an apparatus including a first three-dimensional (3-D) structure and a second 3-D structure. The first 3-D structure may include a first-type doped semiconductor material having semi-polar facets. The second 3-D structure may form a light-emitting diode (LED). The second 3-D structure may include a second-type doped semiconductor material, an active layer, and the first-type doped semiconductor material. The apparatus may also include a conductive layer which at least partially overlays and is in ohmic contact with the semi-polar facets of the first-type doped semiconductor material. The first-type doped semiconductor material of the first 3-D structure and the first-type doped semiconductor material of the second 3-D structure may be etched from a common first-type doped semiconductor epitaxial layer. In some embodiments, the first-type doped semiconductor material may include an N-type doped semiconductor material, and the second-type doped semiconductor material may include a P-type doped semiconductor material.
1. A method comprising:
obtaining a first three-dimensional (3-D) structure and a conductive layer,
wherein the first 3-D structure comprises an N-type doped semiconductor material and including a semi-polar facet of the N-type doped semiconductor material,
wherein the conductive layer at least partially overlays and is in ohmic contact with the semi-polar facet of the N-type doped semiconductor material, and
using the conductive layer as part of an N-type contact for a light-emitting diode (LED) formed as a second 3-D structure comprising a P-type doped semiconductor material, an active layer, and an N-type doped semiconductor material, and
wherein the N-type doped semiconductor material of the first 3-D structure and the N-type doped semiconductor material of the second 3-D structure are etched from a common N-type doped semiconductor epitaxial layer.
2. The method of claim 1 ,
wherein the first 3-D structure has a substantially similar height as the second 3-D structure.
3. The method of claim 2 , wherein the first 3-D structure has a substantially similar mesa shape as the second 3-D structure.
4. The method of claim 3 , wherein both the first 3-D structure and the second 3-D structure have a domed shape.
5. The method of claim 2 , wherein the first 3-D structure and the second 3 -D structure have different shapes.
6. The method of claim 5 , wherein the first 3-D structure has a rectangular plateau shape, and the second 3-D structure has a parabolic shape.
7. The method of claim 1 ,
wherein the conductive layer at least partially overlays the first 3-D structure and supports an N-contact bump bond for the LED,
wherein a second conductive layer at least partially overlays the second 3-D structure and supports a P-contact bump bond for the LED, and
wherein the N-contact bump bond and the P-contact bump bond have similar heights with respect to a substrate on which the first 3-D structure and the second 3-D structure are formed.
8. The method of claim 1 ,
wherein the first 3-D structure further comprises the P-type doped semiconductor material and an active layer,
wherein the P-type doped semiconductor material of the first 3-D structure and the P-type doped semiconductor material of the second 3-D structure are etched from a common P-type doped semiconductor epitaxial layer, and
wherein the active layer of the first 3-D structure and the active layer of the second 3-D structure are etched from a common epitaxial layer.
9. The method of claim 8 , wherein the conductive layer further overlays, at least partially, surfaces of the P-type doped semiconductor material and the active layer of the first 3-D structure.
10. The method of claim 1 ,
wherein the N-type doped semiconductor material of the first 3-D structure further includes a C-plane facet, and
wherein the conductive layer further overlays, at least partially, and is in ohmic contact with, the C-plane facet of the N-type doped semiconductor material.
11. The method of claim 1 , wherein the N-type doped semiconductor material comprises aluminum indium gallium phosphide (AlInGaP).
12. The method of claim 1 , wherein the N-type doped semiconductor material comprises a III-Nitride material.
13. The method of claim 1 , wherein the conductive layer comprises a metal.
14. The method of claim 1 , wherein the conductive layer comprises a transparent conducting oxide.