AlGaAs/GaAs melt-etched inner stripe laser diode with self-aligned structure

A novel liquid phase epitaxy (LPE) used to fabricate a channeled stripe AlGaAs/GaAs laser diode emitting at 780 nm with a self-aligned structure is reported. In the present method, only two-step LPE and a conventional wet chemical etching are required. The inner stripe, 4 μm wide, is grooved by a newly developed preferential melt-etching technique during crystal growth without exposure of the wafer to air. A maximum cw power output of 28 mW per facet without facet coatings and a threshold current of 50 mA are accomplished. Fundamental transverse mode operation up to 10 mW and single longitudinal mode above 2.5 mW are demonstrated.