Low-threshold lasers fabricated by alignment-free impurity induceddisordering

An Si/SiN_x/Si trilayer diffusion source and mask is described and applied to an alignment-free process for fabricating lasers by impurity-induced disordering (IID). Edge-emitting lasers with continuous wave threshold currents of 4.8 mA were achieved, and folded-cavity surface-emitting lasers with Si disordered waveguides were demonstrated for the first time with a threshold of 11 mA. The process that makes possible self-aligned-metallization on a diffusion defined stripe will be useful in fabricating narrow stripe IID lasers and simplify processing for integration of IID waveguide devices