Abstract

Monolithic integration of passive waveguides with double heterostructure (DH) lasers has the potential for a number of interesting device applications, including lasers with distributed Bragg reflectors or integrated external cavities, intensity or frequency modulators, and mode-locked DH lasers. Previous attempts to achieve this structure with GaAs/GaAlAs or GaInAsP/InP systems resulted in relatively high threshold current densities.^(1-6) We have developed in this work a liquid-phase epitaxial (LPE) technique to grow ${\text{Ga}}_{{\text{x}}_2}{\text{In}}_{1-{\text{x}}_2}{\text{As}}_{{\text{y}}_2}{\text{P}}_{1-{\text{y}}_2}/\text{InP}$ DH Passive waveguides integrated with and precisely aligned to previously grown ${\text{Ga}}_{{\text{x}}_1}{\text{ In }}_{1-{\text{x}}_1}{\text{As}}_{{\text{y}}_1}{\text{P}}_{1-{\text{y}}_1}/\text{InP}$ DH laser structures. Uniform waveguide layers and good surface morphology have been achieved in the LPE regrowth. Relatively low threshold current densities (2.4 - 3.1 kA/cm²) were obtained for broad area lasers with one integrated passive waveguide section.

© 1982 Optical Society of America