.cocrpt / Ag Thin-film Magnetic Properties And Microstructure Study

Four series of CoCrPt /Ag films have been prepared by magnetron sputtering onto glass substrates at room temperature. The microstructure and magnetic properties of CoCrPt /Ag nanocomposite films were investigated as functions of the thickness of Ag underlayer and annealing temperature. The properties of [CoCrPt(2.5 nm)/Ag(f nm)]₁₀/Ag(20 nm)were investigated as functions of the thickness of Ag insert-layer and annealing temperature.The microstructure and magnetic properties were measured by X-ray diffraction (XRD), scanning probe microscope (SPM) and vibrating sample magnetometer (VSM). The thickness of Ag underlayer has great effect on the microstructure and magnetic properties of CoCrPt /Ag films. With increasing the thickness of Ag underlayer the coercivity first increases then decreases. When the thickness of Ag underlayer is 20 nm the coercivity reaches the maximum 1.75 × 10⁵ A/m. Its structure is hcp structure lying on the plane. The Ag underlayer makes grains and magnetic domains small and uniform.The as-deposited film is amorphous. The structure of the film annealed at 350℃ is hep structure with Co(10.0) and Co(10.1) lying on the plane. The coercivity increases with increasing of the annealing temperature. Post annealing may diffuse Ag to the magnetic grain boundaries to segregate the grains. The size of the grains first decreases then increases.The thickness of Ag insert-layer has effect on the grain orientation and magnetic properties of [CoCrPt(2.5 nm)/Ag(t nm)]₁₀/Ag(20 nm) multilayers. With increasing the thickness of Ag insert-layer the coercivity first increases then decreases. The coercivity reaches maximum about 2.13 × 10⁵A/m. Well-isolated domains were found in the multilayers.Post annealing leads to increasing the coercivity of [CoCrPt(2.5 nm)/Ag(0.3 nm)]₁₀/ Ag(20 nm). With increasing annealing temperature the coercivity increases and the surface is smoother.