Fabrication of high power 1.5 µm wavelength InGaAsP/InP BH lasers having dilute waveguide structure

1.5 µm wavelength high power buried heterojunction (BH) semiconductor lasers having dilute waveguide structure have been fabricated. The optical field is dragged down toward the n side of the device by the dilute waveguide layer, lowering the optical confinement factor of the p doped material and active material, which helps to enlarge the laser output light power. Compared with thick InGaAsP cladding layer, the dilute waveguide material is easy to be grown and has higher thermal conductivity. The slope efficiency of the obtained dilute waveguide BH lasers is notably higher than that of the BH lasers having no dilute waveguide. Our studies show that the dilute waveguide structure is promising for the fabrication of high power BH lasers.