COMPARATIVE STUDY OF THE PERFORMANCE CHARACTERISTICS OF GREEN InGaN SQW LASER DIODES WITH TERNARY AlGaN AND QUATERNARY AlInGaN ELECTRON BLOCKING LAYER

The effect of built-in polarization on the performance characteristics of green InGaN single quantum well (SQW) laser diode (LD) structures with ternary AlGaN or quaternary AlInGaN electron blocking layer (EBL) having the same bandgap energy, was investigated numerically. Simulation results indicated that using quaternary AlInGaN EBL effectively improves the performance characteristics of green InGaN SQW LDs. Using AlInGaN EBL significantly reduces the built-in polarization and fixed polarization charge densities at the EBL and the last InGaN barrier interface. Furthermore, using quaternary AlInGaN EBL increases the radiative recombination and decreases the non-radiative recombination in the well. The laser structure with AlInGaN EBL has lower threshold current, and higher output power, differential quantum efficiency (DQE) and slope efficiency compared with the laser structure with conventional AlGaN EBL.