Lawretta Ononye

Microstructure of Ion Implanted Sapphire: the Effect of Implantation Temperature and Ionizing Radiation on the Microstructure of Ion Implanted Sapphire Lawretta Ononye

The science of ion implantation technology is concerned with the modification of the near surface properties of a wide range of materials. The technique provides excellent control of implantation parameters such as dose range, energy of ion species and implantation temperature. Alpha-Al2O3 (sapphire) specimens were irradiated at room temperature (RT) and 1000 degree C to fluences of 1x10^17 B+/cm^2, 3x10^16 N+/cm^2 and 1x10^17 Fe+/cm^2 with 150 keV of energy. Following irradiation, the structures were examined using the transmission electron microscopy (TEM), Rutherford backscattering - ion channeling (RBS-C)spectroscopy, optical absorption measurements, x-ray diffraction (XRD) technique, and x-ray photoelectron spectroscopy (XPS). The depth- dependent microstructures of the irradiated specimens, the energy deposited (elastic and inelastic) as a function of depth from the surface, the range of implanted species, and the defect production were modeled using the transport and range of ions in materials (TRIM) program.