Simulation of a ridge-type semiconductor laser for separate confinement of horizontal transverse modes and carriers

In this paper, a ridge-type semiconductor laser with selectively proton-implanted cladding layers is proposed to make the fabrication process more simple, increase kink level, and decrease threshold current. In this semiconductor laser, horizontal transverse modes are confined by the distribution of the effective refractive index; carrier distributions are controlled by selectively proton-implanted cladding layers. The proton-implanted cladding layers have higher refractive index than p-/n-cladding layers by appropriate annealing, because concentrations of the free carriers in the proton-implanted regions are low.