Low Energy Ion Implantation Induced Intermixing in Photonic Devices: Defect Profiling and Evolution

Low energy ion implantation of InP heterostructures has proved to be an efficient way to induce controlled quantum well intermixing. A significant blue‐shift, dependent on local ion dose, appears after a 600°C anneal, which is not observed in the unimplanted regions. Thus, this technique makes possible the fabrication of integrated photonic devices working at several wavelengths. However, it has been observed that the shift is also influenced by the implantation temperature: 200°C implants induce much more intermixing than room temperature implants. In this paper, we will establish a relation between the implant temperature, the induced blue‐shift and the amount of defects in the implanted region, as measured by channeling‐RBS. A much lower defect concentration is observed for higher temperature implants, which implies that a significant number of defects diffuse in‐depth during the implantation in order to provide efficient intermixing.