Appendix E: Reliability and Product Qualification

The development of reliability models and the resulting lifetime predictions across a wide variety of operating conditions was critical to the adoption of vertical‐cavity surface‐emitting lasers (VCSELs) in data communications systems. This appendix presents an approach to reliability modeling, and provides the qualification requirements in several application segments. The purpose of reliability model development is to determine how the operating characteristics of VCSELs will change over device lifetime and different environmental conditions. Like all semiconductor devices, VCSELs are susceptible to damage form electrostatic discharge events. The many diverse application areas and desire for low‐cost packaging options have resulted in VCSELs being operated in non‐hermetic packages and other uncontrolled environments. One unique application requirement for VCSEL reliability has been the use in high‐radiation environments including inside CERN's Large Hadron Collider, space exploration, and even in some aircraft.