Reliability assessment of 1.55-μm vertical cavity surface emitting lasers with tunnel junction using high-temperature aging tests

In this paper, the long-term reliability of all monolithic 1.55-μm etched-mesa vertical cavity surface emitting lasers (VCSELs) with tunnel junction is investigated via high-temperature storage tests and accelerated life tests. Characteristic variations depend on the operating conditions are examined via the threshold current, the optical output power, and the dark current. The median device lifetime is extrapolated and the activation energy of the VCSELs is calculated based on the reliability testing results. In addition, the degradation mechanism of the tested VCSELs is analyzed using the correlation between the current–voltage characteristics (I–V) and the device lifetime. From these results, the long-term reliability of the VCSEL test structures for high-speed optical communication systems can be determined and the device parameters, such as dark current, can be used as a monitoring factor for estimating reliability of the VCSELs.