Effect of annealing temperature and rate of sputtering on the magnetic properties and microstructure of the polycrystalline nickel films with (200) texture

The dependences of the magnetic properties and morphology of polycrystalline nickel (Ni) films with the (200) texture that are fabricated using the dc magnetron sputtering on the SiO 2 /Si(100) substrates on sputtering rate annealing temperature T , and film thickness d are analyzed. It is demonstrated that an increase in the sputtering rate from 17 to 35 nm/min does not affect the saturation magnetization 4π M and ferromagnetic resonance line width Δ H but leads to a significant increase in the coercivity H c for the films whose thickness d is greater than critical thickness d cr ( d > d cr ). It is also demonstrated that d cr depends on both sputtering rate and annealing temperature. The films with the thickness d > d cr exhibit the stripe domain structure whose period increases with increasing d and rate v. The annealing of the films with d ≥ 40 nm at T ≈ 200–400°C results in an increase in Δ H and H c by a factor of 2–4, an increase in 4π M by 25%, an increase in grain size ξ by a factor of 20–30, and the formation of the stripe domain structure in the films that do not exhibit such structure prior to annealing and substantial strengthening of the (200) texture.