Aging Mechanisms of Broad Area ∼800 nm Laser Diodes

This work presents a comprehensive study of early aging behavior (<500>15 cm ⁻³ showed significantly longer delay before the onset of aging (incubation time) than devices with less than 1 × 10 ¹⁵ cm ⁻³ oxygen. Generation-Recombination current and Laser Beam Induced Current measurements indicate that defect densities and aggregation are suppressed at the facets by oxygen, which can explain longer incubation times. Diagnostic data and parametric fits to diode simulation models show that increased cavity optical loss and defect density are primarily responsible for gradual power degradation during aging, rather than changes in nonradiative recombination. Mechanisms are proposed that explain this behavior, based on density functional theory (DFT) simulations and known recombination-enhanced defect generation phenomena.