Effect of different EBL structures on deep violet InGaN laser diodes performance

Some specific designs on band structure near the active region, including the modifications of the material and thickness of the electron blocking layer (EBL), in the deep violet InGaN laser diodes (LDs) are investigated numerically with the ISE TCAD software. The analyses focus on electron and hole carrier injection efficiency, carrier distributions, electron leakage, and radiative recombination, subsequently, optical material gain, and optical intensity. The results indicate that for the ternary AlGaN EBL, the lowest threshold current and the highest output power, slope efficiency, and DQE have been obtained for the 15 nm EBL thickness with 0.22 Al mole fraction. In addition, a comparative study has been conducted on the performance characteristics of the LD structures with a ternary AlGaN EBL and a quaternary AlInGaN EBL with an output emission wavelength at 390 nm. The simulation results showed that the using quaternary AlInGaN EBL effectively improves the LD performance characteristics. (C) 2015 Elsevier Ltd. All rights reserved.