Practical integration method of active devices on SOI photonic integrated circuits

We propose a method of mounting LD chips on SOI substrate and discuss about the optical coupling loss between LDs and Si photonic-wire waveguides. In our scheme, light output from an LD is coupled to the optical waveguides through spot-size-converters (SSC). The simulations show that a minimum optical coupling loss of 1.6 dB and an offset tolerance of ±0.7 μm for the LD chip positioning can be achieved. We measured the optical coupling loss, confirming the validity of the simulations.