Vertical GaN-based LED and method of manufacturing the same

1. A method of manufacturing a vertical GaN-based LED, the method comprising:

forming a GaN-based buffer layer on a sapphire substrate;

forming an undoped GaN layer on the GaN-based buffer layer to obtain crystallinity;

forming an AlGaN layer on the undoped GaN layer;

forming an undoped GaN layer on the AlGaN layer so as to form a 2DEG layer at a junction interface of the AlGaN layer;

sequentially forming an n-type GaN layer, an active layer, and a p-type GaN layer on the undoped GaN layer to form a GaN-based LED structure;

forming a p-electrode on the GaN-based LED structure;

attaching a conductive substrate onto the p-electrode;

removing the sapphire substrate and the GaN-based buffer layer through a laser lift-off (LLO) process, and removing the undoped GaN layer from the AlGaN layer through a chemical mechanical polishing (CMP) process; and

forming an n-electrode on the AlGaN layer from which the undoped GaN layer has been removed.

2. The method according to claim 1 further comprising,

before the forming of the GaN-based buffer layer on the sapphire layer, performing a pre-treatment process on the sapphire substrate such that the surface of the GaN-based buffer layer's surface contacting a top surface of the sapphire substrate has a Ga-face structure in which nitrogen (N) elements are disposed on a vertical uppermost layer of gallium elements.

3. The method according to claim 2 ,

wherein the pre-treatment process is performed using Trimethylgallium (TMGa).

4. The method according to claim 3 ,

wherein the pre-treatment process is performed for 30 seconds through 120 seconds.

5. The method according to claim 1 further comprising

annealing the AlGaN layer in an oxygen atmosphere after the forming of the AlGaN layer.

6. The method according to claim 1 further comprising

forming a reflective layer on the p-electrode before the attaching of the conductive substrate onto the p-electrode.