Investigation of irradiated and annealed high-temperature superconducting films with the Umka nanotechnological complex

Superconducting YBa2Cu3O7 − x films were fabricated by dc magnetron sputtering. They were irradiated with 1.2-MeV He+ ions to doses of 4 × 1015, 8 × 1015, 16 × 1015, and 32 × 1015 cm−2. The irradiated films were subjected to stepwise (30 min per step) vacuum annealing at 500, 600, 700, 800, and 900°C. After vacuum annealing, the samples irradiated to doses of 4 × 1015, 8 × 1015, and 16 × 1015 cm−2 exhibited partial recovery of their critical temperature, whereas the sample with a dose of 32 × 1015 cm−2 exhibited no signs of partial recovery of TC. Investigation of the irradiated annealed samples with the Umka nanotechnological complex has revealed damaged surface regions extended to a relatively large (several tenths of a micrometer) depth.