Reliable InAs quantum dot lasers grown on patterned Si (001) substrate with embedded hollow structures assisted thermal stress relaxation

Direct epitaxial growth of III-V quantum dot (QD) lasers on Si (001) substrates is recognized as a promising and low-cost method for realizing high-performance on-chip light sources in silicon photonic integrated circuits (PICs). Recently, the CMOS-compatible patterned Si (001) substrates with sawtooth structures have been widely implemented to suppress the lattice mismatch induced defects and antiphase boundaries for heteroepitaxial growth of high-quality III-V materials on Si. Considerable progresses have been made on high-performance 1300 nm InAs/GaAs QD lasers on Si (001). Here, we report a thermal stress-relaxed (111)-faceted silicon hollow structures by homoepitaxial method for reliable InAs/GaAs QD lasers growing on Si (001) substrates. Both simulation analysis and experimental results indicate that the voids buried below the sawtooth structures can release about 9% of the accumulative thermal stress of the III-V/Si system during the cooling process. Furthermore, electrically pumped InAs/GaAs QD narrow ridge lasers are grown and fabricated on the specially designed Si (001) platforms with a maximum operation temperature up to 90 degrees C under continuous-wave operation mode. Additionally, an extrapolated lifetime of over 5300 h is calculated from the reliability test at 65 degrees C. These results lead toward high-yield, scalable, and reliable III-V lasers on Si (001) substrates for PICs.