Power dissipation in oxide-confined 980-nm vertical-cavity surface-emitting lasers

We presented 980-nm oxide-confined vertical-cavity surface-emitting lasers (VCSELs) with 16-μm oxide aperture. Optical power, voltage, and emission wavelength are measured in an ambient temperature range of 5 ℃-80 ℃. Measurements combined with an empirical model are used to analyse the power dissipation in device and the physical mechanism contributing to the thermal rollover phenomenon in VCSEL. It is found that the carrier leakage induced self-heating in active region and the Joule heating caused by the series resistance are the main sources of the power dissipation. In addition, carrier leakage induced self-heating increases as injection current increases, resulting in a rapid decrease of the internal quantum efficiency, which is a dominant contribution to the thermal rollover of the VCSEL at larger current. Our study provides useful guideline to design 980-nm oxide-confined VCSEL for thermal performance enhancement.