Abstract
The purpose of this study is to experimentally and theoretically investigate the effects of the implant depth profiles on the high temperature ion implantation. In our theoretical modeling, the implanted ions can interact with implantation-production point defects and with extended sinks such as target surface and dislocations. The synthetic effects of radiation enhanced diffusion, radiation induced segregation, and spatially non-uniform point defect production rate were taken into account and cast into a set of coupled partial-differential equations. The effects of preferential sputtering and lattice dilation were also incorporated into the model through an appropriate coordinate transformation. In the experiment, a tandem accelerator was used for implanting 72 keV Cu-1 ions (5□1015 and 1□1017 Cu-1 ions/cm2) into pure nickel target and implanting 72 keV Ni ions (5□1015 Ni-1 ions/cm2) into pure copper target at elevated temperatures (200.400 and 500 □C). The depth profiles of the implanted ions were measured by secondary ion mass spectrometer. The results demonstrated that the theoretical predictions are in good agreement qualitatively with measured ones, and a set of the best-fit parameters for the theoretical model of Cu-Ni implantation system is obtained. In the 72 keV Cu-1 ions implanted into pure nickel materials, the copper depth profiles are broadened with the increase of the implanted fluence and target temperature. In the 72 keV Ni-1 ions implanted into pure copper materials, the nickel depth profiles tend to broaden and surface concentration increase with temperatures. These effects are mainly due to radiation enhanced diffusion and radiation induced solute segregation to the free surface, which are attributed to the point defects generated during ion implantation at elevated temperatures.