Affiliation: | aResearch Group for Irradiation Field Materials, Japan Atomic Energy Agency (JAEA), Tokai-mura, Ibaraki 319-1195, Japan bResearch Group for Inorganic Functional Materials, Japan Atomic Energy Agency (JAEA), Takasaki-shi, Gunma 370-1292, Japan cResearch Group for Irradiation Field Materials, Japan Atomic Energy Agency (JAEA), Tokai-mura, Ibaraki 319-1195, Japan |
Abstract: | In order to investigate possible structural changes due to high-density electronic excitation, anatase TiO2 thin film specimens were irradiated with 230 MeV 136Xe15+ ions and 200 MeV 197Au13+ ions. X-ray diffraction (XRD) patterns were measured before and after irradiation. The intensity of the XRD peak assigned to the (0 0 4) planes of anatase TiO2 decreases in an exponential manner as a function of ion-fluence. This result can be explained by the formation of the cylindrical damaged regions (i.e. ion tracks) with diameters of 9.6 and 16.3 nm for 230 MeV Xe and for 200 MeV Au ion irradiations, respectively. The difference in the track diameter between Xe ion irradiation and Au ion irradiation can be attributed to the difference in the electronic stopping power (and to the ion-velocity effect, if any). For 200 MeV Au ion irradiation, splitting of the (0 0 4) peak is observed. The original (0 0 4) TiO2 peak remains in the same position, but the new peak shifts to higher angles as fluence increases. |