Implantation of Ni thin films and single crystals with Ag ions

40–130 keV Ag + ions have been implanted at 46 K and 300 K into Ni films (25–38 nm thick) deposited on NaCl and Ni single crystals (100) and (110) in the dose range 10 11 to 4 × 10 16 cm −2. In-situ backscattering measurements and channeling (in the single crystals) have been carried out. The thin films were also analysed using TEM, STEM and EDS. For the single crystal samples it is found that 80% of the Ag is substitutional at the Ag saturation concentration (7–8 at.% max. concentration). Annealing at 623 K. for 1 h, decreases the substitutional fraction to 60%. Bombardment of the thin films at both 46 K and 300 K results in significant recrystallization and grain growth when the ion dose ≳ 10 15cm −2. It is found that D¯∞ϕ and ΔD¯/Δϕ increases with E·ν(E), where D¯ is the average grain diameter, φ is the total ion dose and E·ν(E) is the ion energy deposited in elastic collisions. When the average Ag concentration is ≲ 4 at.%, the Ag atoms are in solution in the Ni matrix; at higher concentrations Ag precipitates (∼ 10nm diameter) are formed. Also, for the high dose implants, the Ni film exhibits a preferred orientation with a 〈110〉 fibre texture. The high density of defects and high strain energy produced by the Ag ion bombardment along with the tendency to reduce the surface energy are considered to cause recrystalization and grain growth of the Ni, and segregation of Ag in the thin film samples.