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 P-type reflective film electrode on the metallic support layer;
a P-type semiconductor layer, an active layer and an N-type semiconductor layer sequentially formed on the P-type reflective film electrode;
an N-type electrode formed on the N-type semiconductor layer; and
a protective layer interposed directly between the P-type reflective film electrode and the P-type semiconductor layer.
2. A light emitting element, comprising:
a metallic support layer;
a reflective layer formed on the metallic support layer;
a P-type reflective film electrode formed in the form of a mesh on the reflective layer;
a P-type semiconductor layer, an active layer and an N-type semiconductor layer sequentially formed on the top of the reflective layer including the P-type reflective film electrode; and
an N-type electrode formed at a desired region on the N-type semiconductor layer,
wherein the reflective layer surrounds the P-type reflective film electrode by contacting the bottom and sides of the P-type reflective film electrode.
3. The light emitting element as claimed in claim 1 , further comprising an insulation film formed at least on a lateral side of the N-type semiconductor layer, and a metallic protective layer for protecting the P-type and N-type semiconductor layers.
4. The light emitting element as claimed in claim 1 , wherein the metallic support layer has a multi-layered support structure.
5. The light emitting element as claimed in claim 1 , wherein the protective layer is formed on a part of lateral and/or bottom sides of the N-type semiconductor layer, active layer and P-type semiconductor layer.
6. The light emitting element as claimed in claim 1 , further comprising an anti-reflective layer wrapping around the P-type semiconductor layer, active layer and N-type semiconductor layer.
7. The light emitting element as claimed in claim 1 , wherein the P-type reflective film electrode comprises a contact metallic layer, a reflective metallic layer, a diffusion barrier layer and a bonding metallic layer.
8. The light emitting element as claimed in claim 1 , wherein the protective layer is formed on part of the P-type reflective film electrode and part of the P-type semiconductor layer.
9. The light emitting element as claimed in claim 1 , wherein the metallic support layer is not wider than the P-type semiconductor layer, the active layer and the N-type semiconductor layer.
10. The light emitting device as claimed in claim 1 , wherein the N-type electrode comprises a single electrode arranged substantially on a central portion of the N-type semiconductor layer.
11. A light emitting element, comprising:
a metallic support layer;
a reflective layer formed on the metallic support layer;
a P-type reflective film electrode formed in the form of a mesh on the reflective layer;
a P-type semiconductor layer, an active layer and an N-type semiconductor layer sequentially formed on the top of the reflective layer including the P-type reflective film electrode;
an N-type electrode formed at a desired region on the N-type semiconductor layer; and
a protective layer interposed between the P-type reflective film electrode and the P-type semiconductor layer.
12. The light emitting device as claimed in claim 11 , wherein the protective layer and a side of the reflective layer form a substantially planar surface.
13. The light emitting device as claimed in claim 11 , wherein portions of the reflective layer contact the protective layer.
14. A light emitting element, comprising:
a metallic support layer;
a reflective layer formed on the metallic support layer;
a P-type reflective film electrode formed in the form of a mesh on the reflective layer;
a P-type semiconductor layer, an active layer and an N-type semiconductor layer sequentially formed on the top of the reflective layer including the P-type reflective film electrode; and
an N-type electrode formed at a desired region on the N-type semiconductor layer,
wherein the P-type reflective film electrode is directly on the reflective layer.
15. The light emitting device as claimed in claim 2 , further comprising a second metallic support layer interposed directly between the metallic support layer and the reflective layer.