Record-Low Thermal Resistance, 12.5 Gbit/s Capable Flip-Chip Bonded 850 nm Wavelength 2-D VCSEL Arrays

This paper presents a novel fabrication scheme for mesa-isolated monolithic vertical-cavity surface-emitting lasers (VCSELs) based on fully self-aligning processes. In the new design, heat extraction from the devices' active regions is strongly enhanced, resulting in record-low thermal resistances. The improved heat sinking does not introduce parasitics that would interfere with the dynamic properties of these high-speed sources, and they can hence take full advantage of high-current operation at lower internal temperatures, which generally also increases device lifetime. High operating currents are needed for VCSELs to achieve high bandwidths and flat transfer functions.