Focused ion-beam implantation induced thermal quantum-wellintermixing for monolithic optoelectronic device integration

摘要

By focused ion beam implantation induced thermal intermixing thenbandgap of quantum-well layer structures can be selectively changed.nThis allows lateral bandgap engineering and gives a new degree ofnfreedom for lateral structuring. The principle technological aspectsnlike the dependence of the bandgap shift on implantation parameters andnthe spatial resolution are investigated and applied to the fabricationnof photonic and optoelectronic devices. Lateral waveguiding in InP-basednmaterials, the possibility of monolithic integration of bandgap shiftednwaveguide areas into active devices and the improvement of the lateralncarrier confinement in ridge waveguide lasers are demonstrated. Due tonthe high spatial resolution, modulated bandgap gratings could benrealized with periods down to 90 mn. These bandgap gratings were used toncreate gain-coupled distributed-feedback lasers in different materialnsystems with well controlled single-mode emission