Integration of a thin film III–V edge emitting laser and a polymer microring resonator on an SiO₂/Si substrate

The planar integration of on-chip laser sources with optical sensing elements, waveguide optical interconnect, and detectors enables the implementation of portable, efficient chip-scale systems, with applications in areas that include medical, environmental, biological, and chemical sensing systems. In this paper, the planar integration of a thin film strain compensated In_0.2Ga_0.8As/GaAs single quantum well laser with a tapered polymer (SU-8-2002) waveguide and overlap coupled SU-8-2002 microring resonator is achieved on an SiO₂/Si platform. Two laser/waveguide configurations, one with the tapered waveguide separated from the laser front facet and the other with the waveguide overlapping the front facet, were demonstrated, and this laser/waveguide structure was then integrated with a polymer microring resonator on SiO₂/Si. Lasing operation for the integrated system was verified through power-current characteristics and spectra at the through and drop ports of the microring resonator. This integrated system forms an essential component toward realizing planar chip-scale optical sensing systems.