Abstract: Ni₈₀Fe₂₀ films with thickness about 54nm were deposited on K9 glass and thermally oxidized silicon substrates at ambient temperature by electron beam evaporation with deposition rate about 1.8nm/min. The as-deposited films were annealed at 350, 450 and 570℃ respectively for 1h. After annealing at 570℃, the anisotropic magnetoresistance  ratio(R_AM) of the films is greatly improved. It increases to 3%-3.5% nearly about three times of that of the as-deposited films. The grain size increases with the annealing temperature and the ［111］ crystal orientation is obviously enhanced after annealing at temperature above 450℃. The internal stress  in the films deposited on K9 glass is compressive and the resistance measurement shows that R_M∥ is larger than R_M⊥ in these films. However, in the films deposited at the same conditions but on oxidized silicon substrates, the internal stress is tensile and R_M⊥ is larger than R_M∥. The differences of R_M∥ and R_M⊥ in two series of specimens are discussed.

Key words: Ni₈₀Fe₂₀ film; annealing; internal stress; anisotropic magnetoresistance