High-efficiency GaN-based vertical light-emitting diodes with periodic beveled rod-shaped structures

Area of Science:

• Materials Science and Engineering
• Optoelectronics
• Semiconductor Physics

Background:

• Gallium Nitride (GaN)-based vertical light-emitting diodes (VLEDs) are crucial optoelectronic devices.
• Improving light-extraction efficiency is a key challenge for VLED performance.
• Surface texturing is a common strategy to enhance light extraction.

Purpose of the Study:

• To investigate the effect of periodic beveled micro-rods (BMRs) on the emission surface of GaN-based VLEDs.
• To enhance the light-extraction efficiency and light output power of VLEDs.

Main Methods:

• Fabrication of GaN-based VLEDs with periodic beveled micro-rods (BMRs) on the emission surface.
• Comparison of BMR-VLEDs with VLEDs featuring a randomly textured surface (RT-VLED).
• Experimental measurement of light output power at a specific injection current (350 mA).

Main Results:

• The light output power of BMR-VLEDs was enhanced by approximately 15.6% compared to RT-VLEDs.
• The periodic BMR structure facilitated efficient out-coupling of photons from the active layer.
• Increased photon escape probability was observed due to the BMR surface modification.

Conclusions:

• Periodic beveled micro-rods are an effective surface structure for enhancing light extraction in GaN-based VLEDs.
• The BMR structure significantly improves the light output power of VLEDs.
• This approach offers a viable method for optimizing VLED performance.