Analysis of current spreading in long-wavelength, vertical-cavity, surface-emitting lasers

Summary form only given. Current spreading is a major concern for wafer-bonded 1.3-/spl mu/m and 1.55-/spl mu/m vertical-cavity, surface-emitting lasers (VCSELs) because the distance between the active layer and the aperture for wafer-bonded VCSELs is significantly greater than that for shorter wavelength VCSELs. The current spreading problem becomes even more severe for VCSELs with dielectric top mirrors due to carrier injection from the peripheral region of the aperture, as opposed to direct carrier injection to the aperture through the semiconductor Bragg mirror. We have numerically analyzed the current spreading problem for four popular 1.3-/spl mu/m and 1.55-/spl mu/m VCSEL structures. Two structures have n-GaAs/AlGaAs Bragg mirrors, with oxygen implantation and selective AlGaAs oxidation for current confinement, respectively. The other two structures have p-GaAs/AlGaAs Bragg mirrors, with similar current confinement structures. Common to all four devices are their wafer-bonded GaAs/AlGaAs mirrors and top dielectric mirrors.