Principal scheme of the setup used for the PL degradation experiments under high power laser excitation.
Sample structure with corresponding schematic sketch of the band gap energy and photon energy of the exciting laser used for the PL experiments.
Degradation behavior of short wavelength LED structures under electrical overstress and optical laser induced photoluminescence degradation experiments. The EL and PL intensities are normalized with the initial ones and , respectively, measured at the beginning of the particular degradation experiment.
Photoluminescence degradation behavior for different stress laser power densities under intense laser excitation (symbols) and corresponding fit curves after the model of Lam et al.(solid lines).
Dependence of the defect evolution rate describing the negative PL degradation component on stress laser power density (symbol) with corresponding parabolic fit (solid line).
Dependence of the weighting parameters Ki and of the initial number of defects of type 2 on the stress laser power.
PL degradation behavior for different measurement laser power densities stressed with the same laser power density (symbols) and corresponding fit curves after the model of Lam (solid lines).
Dependence of the weighting parameters Ki and of the three PL degradation mechanisms on the measurement laser power densities (symbols). The dashed lines are guides for the eyes.
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