InGaN Based C-Plane Blue Laser Diodes on Strain Relaxed Template with Reduced Absorption Loss

InGaN based c-plane blue LDs on strain relaxed template (SRT) with a reduced absorption loss was demonstrated. The loss is reduced from 27 cm−1 to 20 cm−1. Due to the lower loss, threshold current density is improved from 51.1 kA/cm2 to 43.7 kA/cm2, and slope efficiency is also increased by a factor of 1.22. The absorption loss from decomposition layer (DL) in SRT is confirmed to be a major extra loss source by both experimental and simulation results. With a higher indium content in buffer and waveguide layers, optical leakage into DL can be suppressed.