Focused ion beam technology: A new approach for the fabrication of optoelectronic devices

High resolution focused ion beam implantation was used for the definition of key elements for the monolithic integration of optoelectronic devices like waveguide sections and distributed feedback gratings. By implantation induced thermal intermixing the band gap in semiconductor heterostructures can be shifted with high spatial resolution. In InP-based material, e.g., a maximum band gap shift of 65 meV was achieved, which can be controlled by the implantation dose. Due to the small beam diameter first order gain coupled gratings were realized in InP, GaAs and ZnSe based material systems, which allows single mode laser operation from the long wavelength (1.5 μm) down to the blue emitting regime (