Comprehensive reliability study of high-speed 850nm VCSELs for optical links in AI and data center

850 nm vertical-cavity surface-emitting lasers (VCSELs) are widely deployed in high-speed optical interconnects within AI clusters and data centers, where long-term reliability is critical. This work presents a comprehensive reliability evaluation of oxide-confined 850 nm VCSELs supporting 53 Gbps and 106 Gbps PAM4 modulation. Accelerated wearout tests were conducted under elevated current and temperature conditions, up to 11 mA and 140 °C, to investigate longterm degradation behavior. Using an Arrhenius-based lifetime model, the extrapolated time to 1% failure (TT1%F) under nominal operating conditions exceeds 3,000 years. High-speed performance of lasers failed with power drop below 20% mark after accelerated wear-out tests were subsequently measured. Interestingly, their TDECQ and BER values are well below the IEEE 802.3 limits,