Vertical structure LEDs
A light-emitting device can include a conductive support structure comprising a metal; a GaN-based semiconductor structure disposed on the conductive support structure, the GaN-based semiconductor structure including a p-type GaN-based layer, a GaN-based active layer and an n-type GaN-based layer, in which the GaN-based semiconductor structure has a first surface, a side surface and a second surface, in which the first surface, relative to the second surface, is proximate to the conductive support structure, in which the second surface is opposite to the first surface, in which the conductive support structure is thicker than the p-type GaN-based semiconductor layer, and the conductive support structure is thicker than the n-type GaN-based semiconductor layer; a p-type electrode disposed on the conductive support structure; an n-type electrode disposed on the second surface of the GaN-based semiconductor structure; and a passivation layer disposed on the side surface and the second surface of the GaN-based semiconductor structure.
1. A light-emitting device, comprising:
a conductive support structure comprising a metal;
a GaN-based semiconductor structure disposed on the conductive support structure, the GaN-based semiconductor structure including a p-type GaN-based layer, a GaN-based active layer and an n-type GaN-based layer, wherein the GaN-based semiconductor structure has a first surface, a side surface and a second surface, wherein the first surface, relative to the second surface, is proximate to the conductive support structure, wherein the second surface is opposite to the first surface, wherein the conductive support structure is thicker than the p-type GaN-based semiconductor layer, and wherein the conductive support structure is thicker than the n-type GaN-based semiconductor layer;
a p-type electrode disposed on the conductive support structure;
an n-type electrode disposed on the second surface of the GaN-based semiconductor structure; and
a passivation layer disposed on the side surface and the second surface of the GaN-based semiconductor structure,
wherein the passivation layer comprises:
a first portion disposed on the second surface of the GaN-based semiconductor structure; and
a second portion disposed between the conductive support structure and the first surface of the GaN-based semiconductor structure,
wherein the first portion is overlapped with the second portion in a thickness direction of the GaN-based semiconductor structure, and
wherein the first portion has a width greater than a width of the second portion.
2. The light-emitting device according to claim 1 , wherein a thickness of the GaN-based semiconductor structure is 100 times or less than a thickness of the p-type GaN semiconductor layer.
3. The light-emitting device according to claim 1 , wherein a thickness of the GaN-based semiconductor structure is 5 times or less than a thickness of the n-type GaN semiconductor layer.
4. The light-emitting device according to claim 1 , wherein a thickness of the GaN-based semiconductor structure is 1.7 times or less than a thickness of the n-type GaN semiconductor layer.
5. The light-emitting device according to claim 1 , wherein the conductive support structure comprises Cu.
6. The light-emitting device according to claim 1 , wherein the GaN-based semiconductor structure is less than about 5 microns thick.
7. The light-emitting device according to claim 1 , wherein the passivation layer covers a side surface and an upper surface of the n-type electrode.
8. The light-emitting device according to claim 7 , wherein an area of the passivation layer covering the side surface of the n-type electrode is larger than an area of the passivation layer covering the upper surface of the n-type electrode.
9. The light-emitting device according to any one of claims 7 , further comprising a metal pad disposed on the passivation layer covering the upper surface of the n-type electrode.
10. The light-emitting device according to any one of claims 7 , wherein the passivation layer covering the upper surface of the n-type electrode is patterned to form an open space to expose the upper surface of the n-type electrode.
11. The light-emitting device according to claim 1 , wherein an area of the passivation layer covering the n-type GaN-based layer is larger than an area of the passivation layer covering the p-type GaN-based layer.
12. The light-emitting device according to claim 1 , wherein an area of the passivation layer covering the n-type GaN-based layer is larger than an area of the passivation layer covering the GaN-based active layer.
13. The light-emitting device according to claim 7 , wherein an area of the passivation layer covering the n-type GaN-based layer is larger than an area of the passivation layer covering the side surface of the n-type electrode.
14. The light-emitting device according to claim 7 , wherein an area of the passivation layer covering the n-type GaN-based layer is larger than an area of the passivation layer covering the upper surface of the n-type electrode.
15. A light-emitting device, comprising:
a conductive support structure comprising a metal;
a GaN-based semiconductor structure disposed on the conductive support structure, the GaN-based semiconductor structure including a p-type GaN-based layer, a GaN-based active layer, and an n-type GaN-based layer, wherein the GaN-based semiconductor structure has a first surface, a side surface and a second surface, wherein the first surface, relative to the second surface, is proximate to the conductive support structure, and wherein the second surface is opposite to the first surface;
a p-type electrode disposed on the conductive support structure;
an n-type electrode disposed on the second surface of the GaN-based semiconductor structure; and
a passivation layer extends from the side surface of the GaN-based semiconductor structure to cover the second surface of the GaN-based semiconductor structure and a side surface and an upper surface of the n-type electrode,
wherein the passivation layer comprises:
a first portion disposed on the second surface of the GaN-based semiconductor structure; and
a second portion disposed between the conductive support structure and the first surface of the GaN-based semiconductor structure,
wherein the first portion is overlapped with the second portion in a thickness direction of the GaN-based semiconductor structure, and
wherein the first portion has a width greater than a width of the second portion.
16. The light-emitting device according to claim 15 , wherein a thickness of the GaN-based semiconductor structure is 100 times or less than a thickness of the p-type GaN semiconductor layer.
17. The light-emitting device according to claim 15 , wherein a thickness of the GaN-based semiconductor structure is 5 times or less than a thickness of the n-type GaN semiconductor layer.
18. The light-emitting device according to claim 15 , wherein a thickness of the GaN-based semiconductor structure is 1.7 times or less than a thickness of the n-type GaN semiconductor layer.
19. The light-emitting device according to claim 15 , wherein the conductive support structure comprises Cu.
20. The light-emitting device according to claim 15 , wherein the GaN-based semiconductor structure is less than about 5 microns thick.