Fabrication-Efficient Flip-Chip-Bondable 850-nm VCSELs With an X-Shaped Vertical Cavity

We present a novel approach to flip-chip-bondable vertical-cavity surface-emitting lasers and 2-D arrays emitting at 850 nm, the standard for multimode fiber optical interconnects. A unique sequence of wet-etching steps renders laser fabrication particularly efficient and allows the incorporation of near-cavity heat spreaders. Record-low thermal resistances of substrate-removed devices are achieved without compromising the dynamic properties.