Enhancement of Light Power for Blue InGaN LEDs by Using Low-Indium-Content InGaN Barriers

The optical properties of blue InGaN LEDs that emit in a spectral range from 410 to 445 nm are theoretically investigated by using the APSYS simulation program. It is found that the light performance can be enhanced effectively when the conventional GaN barrier layers are replaced by In_0.02Ga_0.98N and In_0.05Ga_0.95N barrier layers. The numerical results indicate that the output power of LEDs with In_0.02Ga_0.98 N barrier layers is improved gradually above the emission wavelength of 410 nm. However, when the In_0.05Ga_0.95N barrier layers are used, the emitting power of LEDs varies significantly when the emission wavelength changes. When the emission wavelength is 410 nm, the use of GaN and In_0.02Ga_0.98N barrier layers can lead to higher output power. However, if the emission wavelength is 445 nm, the use of In_0.05Ga_0.95N barrier layers is beneficial for maintaining high output power.