Thermal management of VCSEL-based optoelectronic modules

The development of reliable optoelectronic modules based on vertical-cavity surface-emitting lasers (VCSELs) will depend strongly on proper thermal management. One of the module's critical thermal paths is from a VCSEL to a heat sink, which is affected by packaging technologies and materials. The measured VCSEL-to-case resistance of a laser with 8-/spl mu/m aperture was 1650/spl deg/C/Watt, and that of a 20-/spl mu/m device was 1070/spl deg/C/Watt. To study the packaging effects, a 3-D numerical model has been developed and calibrated by the measured data. The calibrated model was used to understand the difference in thermal behavior (1) between a wire-bonded and a flip-chip VCSEL module, (2) between a single-VCSEL and an 8/spl times/8-VCSEL module, and (3) between a bottom-cooled and an top-cooled module.