Efficient continuous wave operation of vertical-cavity semiconductor lasers using buried-compensation layers to optimize current flow

The lateral definition of vertical-cavity surface-emitting lasers (VCSELs) using buried ion implantation and the optimization of this process are described. A VCSEL structure was grown, and lasers were laterally defined using deep proton implantation process. The buried implantation process created a funnel shape current path into the laser active region. By optimizing this process, a serial resistance of 50 Ω, 2.1 mW continuous wave output power and a 1 V lower ‘‘turn on’’ voltage were achieved for an optimum dose of 1×1013 ions/cm2 for 10×10 μm2 lasers. These improvements were achieved, while retaining the same low threshold current level of fully confined VCSELs.