GaN based group III-V nitride semiconductor light-emitting diode and method for fabricating the same
A GaN based III-V nitride semiconductor light-emitting device and a method for fabricating the same are provided. In the GaN based III-V nitride semiconductor light-emitting device including first and second electrodes arranged facing opposite directions or the same direction with a high-resistant substrate therebetween and material layers for light emission or lasing, the second electrode directly contacts a region of the outmost material layer exposed through an etched region of the high-resistant substrate. A thermal conductive layer may be formed on the bottom of the high-resistant substrate to cover the exposed region of the outmost material layer.
1. A method for fabricating a light-emitting device, the method comprising:
(a) sequentially forming a first compound semiconductor layer, an active layer, and a second compound semiconductor layer, which are for inducing light emission, on a high-resistant substrate;
(b) forming a light-reflecting conductive layer on the second compound semiconductor layer;
(c) etching a region of the high-resistant substrate to expose the first compound semiconductor layer; and
(d) forming a light-transmitting conductive layer to cover the exposed region of the first compound semiconductor layer.
2. The method of claim 1 , wherein step (c) comprises:
polishing the bottom of the high-resistant substrate; and
exposing the bottom of the first compound semiconductor layer by etching the region of the high-resistant substrate.
3. The method of claim 2 , wherein the high-resistant substrate is a sapphire substrate.
4. The method of claim 2 , wherein the bottom of the high-resistant substrate is polished by grinding or lapping.
5. The method of claim 2 , wherein the high-resistant substrate is dry etched using a reaction gas comprising at least Cl 2 or BCl 3 .
6. The method of claim 5 , wherein the reactant gas further comprises Ar gas.
7. The method of claim 2 , wherein the high-resistant substrate is etched to form a via hole through which the bottom of the first compound semiconductor layer is exposed.
8. The method of claim 2 , wherein the high-resistant substrate is etched to expose a portion of the bottom of the first compound semiconductor layer that is larger than a portion of the first compound semiconductor layer that remains in contact with the high-resistant substrate after etching.
9. The method of claim 1 , further comprising forming a pad layer on the light-transmitting conductive layer.
10. A method for fabricating a light-emitting device, the method comprising:
(a) sequentially forming a first compound semiconductor layer, an active layer, and a second compound semiconductor layer, which are for inducing light emission, on a high-resistant substrate;
(b) forming a light-reflecting conductive layer on the second compound semiconductor layer;
(c) etching a region of the high-resistant substrate to expose the first compound semiconductor layer; and
(d) forming a light-transmitting conductive layer to cover the exposed region of the first compound semiconductor layer,
wherein the high-resistant substrate is dry etched using a reaction gas comprising at least Cl 2 or BCl 3 .
11. The method of claim 10 , wherein the reactant gas further comprises Ar gas.