InGaN quantum well with gradually varying indium content for high-efficiency GaN-based green light-emitting diodes

Area of Science:

• Solid State Physics
• Optoelectronics
• Materials Science

Background:

• Gallium nitride (GaN)-based green light-emitting diodes (LEDs) are crucial for advanced display technologies.
• Improving efficiency and mitigating efficiency droop in green LEDs remains a significant challenge.

Purpose of the Study:

• To enhance the performance of GaN-based green LEDs by introducing InGaN quantum wells with gradually varying indium (In) content.
• To investigate the impact of gradual In content on quantum-confined Stark effect (QCSE) and Auger recombination.

Main Methods:

• Fabrication and characterization of GaN-based green LEDs utilizing InGaN quantum wells with gradually varying In composition.
• Comparison of device performance (light output power and efficiency droop) against LEDs with constant In content quantum wells.

Main Results:

• Gradual In content InGaN quantum wells effectively alleviate the quantum-confined Stark effect (QCSE).
• Devices exhibited a lower Auger recombination rate compared to constant In content LEDs.
• At 60 A/cm², light output power increased from 33.9 mW (constant In) to 55.2 mW (gradual In).
• At 150 A/cm², efficiency droop decreased from 61% (constant In) to 37.6% (gradual In).

Conclusions:

• The proposed gradual In content InGaN quantum well structure offers a viable method for enhancing green LED performance.
• This approach demonstrates significant potential for technological and commercial effectiveness in replacing constant In content quantum wells.