In this paper, we investigate sputtered physical vapor deposition (PVD) AlN nucleation layer effects on crystal quality and efficiency of GaN-based light-emitting diodes (LEDs) prepared on high-aspect ratio patterned sapphire substrate (HARPSS). The crystal quality of the GaN epitaxial layer prepared on HARPSS with a PVD AlN nucleation layer was significantly better than that with a conventional metal organic chemical vapor deposition (MOCVD)-grown AlN nucleation layer. In addition, the pure wurzite structure GaN prepared on HARPSS could be obtained using PVD AlN nucleation layer. With the PVD AlN nucleation layer, the 20-mA LED light output power of the LEDs can be enhanced by 47.7% compared with the LEDs with the conventional MOCVD-grown AlN nucleation layer.
- light-emitting diodes (LEDs)
- patterned sapphire substrate (PSS)
- physical vapor deposition (PVD).