Characterization and reliability of GaN Laser Diodes emitting in the blue, skyblue and violet visible regions

The aim of this thesis is to study the characterization and reliability of InGaN/GaN Blue, Skyblue and Violet Laser Diodes provided by Nichia Corporation. The analysis is conducted with electrical, capacitive, optical and thermal measurements. The reliability tests have been carried out with different stress currents at 70°C, in order to obtain a 60mW and 90mW optical output power, and finally with fixed currents at 200mA. All results reveal an increase of threshold current and a slightly change in slope efficiency. On I-V measurements some devices present a great degradation on reverse polarization. Then, internal quantum efficiency due to radiative and non-radiative recombination has been calculated, and also the variation in recombination time respectively. Finally spectrometry measurements have been carried out, analyzing spectrum depending on temperature and injected current