Popis: |
The reliability of novel, electrically pumped, vertical cavity 980-nm InGaAs lasers is demonstrated through accelerated life testing (ALT). The ALT methodology is used to detect failure modes as well as to obtain failure statistics. The time-to-failure (TTF) distribution and acceleration model are determined from over 200 devices tested from multiple wafers and assembly lots to account for process variation. The failure mode observed was gradual power degradation, while all other laser diode characteristics, e.g., threshold current, operating current and wavelength, remained stable. Laser output power degraded linearly in t1/2, where t is the stress time. The acceleration model best fitting the data is Black's equation with thermal activation energy of 0.89 eV and current density coefficient of 2.9. Verification of the acceleration model was confirmed through life testing over 500 devices at field operating conditions. The high level of reliability demonstrated meets strict telecommunications requirements. |