GaAs Templates Selectively Grown on Silicon-on-Insulator for Lasers in Silicon Photonics

Realizing efficient on-chip light sources on Si is a crux for Si-based photonic integrated circuits (PICs). Lateral aspect ratio trapping (LART) by MOCVD for selective epitaxy of III-V materials on (001) silicon-on-insulator (SOI) is a promising technique for monolithic integration of light sources on silicon and deployment of Si-based PICs. In this report, a monolithic microscaled GaAs/Si platform is obtained through the selective growth of GaAs membranes on industry-standard (001)-oriented SOI wafers by the LART technique. The GaAs membranes are laterally grown from {111}-oriented Si surfaces inside patterned oxide trenches, with dimensions defined by lithography. GaAs microdisk lasers (MDLs) fabricated on the GaAs membranes laterally grown on (001) SOI lase at room temperature (RT) by optical pumping. RT-pulsed lasing was achieved with a threshold of 880 μJ/cm². This work provides a crucial step toward fully integrated Si photonics.