Distributed feedback surface-emitting laser with air/semiconductor gratings embedded by mass-transport assisted wafer fusion technique

We report on a distributed feedback InGaAsP MQW laser with air/semiconductor gratings embedded by wafer-fusion technique with the assistance of mass-transport phenomenon for the first time. The air/semiconductor gratings with 0.4-μm period and 0.2-μm depth are successfully fabricated inside the device, and a single longitudinal mode oscillation at about 1.28 μm is demonstrated under pulsed condition at room temperature. The threshold current density is estimated to be about 1.4 kA/cm2. It is also shown that the device has a surface-emitting function since it has a low loss multiquantum-well waveguide with grating output coupler.