Three Channels Buried Crescent InGaAsP Laser with 1.51 μm Wavelength on Semi-insulating InP

Laser diodes operating at the 1.5 μm wavelength region can find important applications for long distance optical fiber communication systems. In this letter we report a recently developed three channels buried crescent (TCBC) laser structure operating at 1.51 μm wavelength. This laser structure is similar to structures reported earlier1,2 for 1.2-1.3 μm wavelength operation, but with some modifications necessary to achieve good performance at 1.51 μm wavelength. In the present structure two additional channels are etched on both sides of the laser waveguide channel before the Liquid Phase Epitaxy (LPE) growth process. Because of rapid LPE growth at the edges of these channels, the growth rate is reduced at the central laser waveguide channel. This is important for achieving better control over the thickness of the 1.51 μm InGaAsP active region which has higher growth rates than the 1.3 μm InGaAsP layers.3