SELF-ALIGNED HIGH-QUALITY TOTAL INTERNAL-REFLECTION MIRRORS

High-quality total internal reflection (TIR) mirrors are fabricated by a new self-aligned etch process,using SiCl, reactive ion etching (RIE), The self-aligned etch process requires only a single SiO2 mask layer without additional dielectric depositions and lift-off steps. The reflectivity of the TIR mirrors are measured by characterizing InGaAs-GaAs-AlGaAs strained-layer quantum-well heterostructure crank lasers that consist of crank-shaped ridge waveguides with two TIR mirrors and two cleaved facets, It is found that the self-aligned TIR mirrors have a very high reflectivity of 0.90 (0.46 dB/90 degrees loss).