GaN compound semiconductor light emitting element and method of manufacturing the same
View Patent ↗The present invention relates to a gallium nitride (GaN) compound semiconductor light emitting element (LED) and a method of manufacturing the same. The present invention provides a vertical GaN LED capable of improving the characteristics of a horizontal LED by means of a metallic protective film layer and a metallic support layer. According to the present invention, a thick metallic protective film layer with a thickness of at least 10 microns is formed on the lateral and/or bottom sides of the vertical GaN LED to protect the element against external impact and to easily separate the chip. Further, a metallic substrate is used instead of a sapphire substrate to efficiently release the generated heat to the outside when the element is operated, so that the LED can be suitable for a high-power application and an element having improved optical output characteristics can also be manufactured. A metallic support layer is formed to protect the element from being distorted or damaged due to impact. Furthermore, a P-type electrode is partially formed on a P-GaN layer in a mesh form to thereby maximize the emission of photons generated in the active layer toward the N-GaN layer.
1. A light emitting element, comprising:
a metallic support layer;
a reflective film electrode arranged on the metallic support layer;
a nitride semiconductor structure arranged on the reflective film electrode, the nitride semiconductor structure comprising a first-type nitride semiconductor layer, an active layer, and a second-type nitride semiconductor layer;
an anti-reflective layer arranged on the nitride semiconductor structure;
an insulation layer, the nitride semiconductor structure being arranged on the insulation layer, and the insulation layer extending beyond an edge of the nitride semiconductor structure; and
a metallic protective film layer, the reflective film electrode and the insulation layer being arranged on the metallic protective film layer.
2. The light emitting element of claim 1 , wherein a portion of the insulation layer is disposed directly between the reflective film electrode and the nitride semiconductor structure.
3. The light emitting element of claim 1 , wherein the reflective film electrode comprises a contact metallic layer comprising Ni, Pt, Ru, Ir, Rh, Ta, Ti, W, Pd, V, Co, Au, Re or any combination thereof, and a reflective metallic layer comprising Ag, Al, or a combination thereof.
4. The light emitting element of claim 3 , wherein the thickness of the contact metallic layer is 5 Å to 500 Å.
5. The light emitting element of claim 3 , wherein the thickness of reflective metallic layer is 100 Å to 9000 Å.
6. The light emitting element of claim 3 , wherein the thickness of the reflective metallic layer is 1000 Å to 2000 Å.
7. The light emitting element of claim 3 , wherein the reflective film electrode further comprises a diffusion barrier layer.
8. The light emitting element of claim 7 , wherein the diffusion barrier layer comprises Ru, Ir, Re, Rh, Os, V, Ta, W, Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), RuO 2 , VO 2 , MgO, IrO 2 , ReO 2 , RhO 2 , OsO 2 , Ta 2 O 3 , WO 2 , or any combination thereof.
9. The light emitting element of claim 7 , wherein the thickness of the diffusion barrier layer is 50 Å to 1000 Å.
10. The light emitting element of claim 7 , wherein the reflective film electrode further comprises a bonding layer.
11. The light emitting element of claim 10 , wherein the bonding layer comprises a first bonding layer and a second bonding layer.
12. The light emitting element of claim 10 , wherein the bonding layer comprises Ni, Cr, Ti, Pd, Ru, Ir, Rh, Re, Os, V, Ta, Au, Pd, Pt, or any combination thereof.
13. The light emitting element of claim 1 , wherein the anti-reflective layer comprises ITO, SiO 2 , Si 3 N 4 , or IZO.
14. The light emitting element of claim 1 , wherein the insulation layer is arranged on a side surface of the active layer.
15. The light emitting element of claim 1 , wherein the anti-reflection layer extends beyond an edge of the nitride semiconductor structure.
16. The light emitting element of claim 1 , wherein the metallic support layer comprises a multi-layered structure,
wherein the multi-layered structure comprises a first layer comprising Au, Ni, W, Mo, Cu, Al, Ta, Ag, Pt, Cr, or any combination thereof, and a second layer comprising Au, Ni, W, Mo, Cu, Al, Ta, Ag, Pt, Cr, and any combination thereof.
17. The light emitting element of claim 1 , wherein the metallic support layer comprises a conductive ceramic film or a semiconductor doped with impurities.
18. The light emitting element of claim 17 , wherein the metallic support layer comprises SrTiO 3 doped with Nb, ZnO doped with Al, ITO, IZO, Si doped with B, Si doped with As, or diamond doped with impurities.
19. The light emitting element of claim 1 , wherein the insulation layer covers a side surface of the second-type semiconductor layer.
20. The light emitting element of claim 19 , wherein the metallic protective film layer covers a portion of the insulation layer that covers the side surface of the second-type semiconductor layer.