Optical and electrical improvements of semipolar (1 1 −2 2) GaN-based light emitting diodes by Si doping of n-GaN template

• In semipolar GaN, Si-doping is effective to reduce out-of plane PSFs toward [1−100].
• Interfacial quality of semipolar QWs was improved by increasing SiH4 flow of n-GaN.
• Electrical properties of semipolar GaN were improved by increasing Si doping.
• Light output power of semipolar LEDs were increased with SiH4 flow rate of n-type GaN.

We report that the performance of semipolar (1 1 −2 2) GaN-based light-emitting diodes (LEDs) was improved by increasing the Si-doping concentration of n-type GaN templates. In-plane and out-of plane high-resolution X-ray diffraction demonstrated that crystal defects such as threading dislocation, partial stacking faults and basal stacking faults, were significantly decreased by increasing the Si-doping concentration. This resulted in the increase of carrier mobility due to reduction of the defect-scattering effect. Furthermore, the quality of InGaN/GaN quantum-well interfaces was improved by increasing the Si-doping concentration of the n-type GaN template. Based on these results, we suggest that the light-output power and operation voltage of semipolar (1 1 −2 2) GaN-based LEDs would be improved by increasing Si doping concentration of n-type GaN templates.