UNIAXIAL MAGNETIC FEC THIN-FILMS SPUTTERED ONTO POLYMER SUBSTRATES

Thin films of FeC were deposited onto a polymer substrate by reactive DC magnetron sputtering, using an argon and hydrocarbon gas mixture. T he polymer web is wound by a roll coater, and an individual thin film with a constant thickness is piled up by increasing a number of passes up to a desired thickness. Uniaxial films with Hk= 4000 A/m and low d ispersion were obtained. The coercive force was a function of thicknes s; it was Hc = 8A/m for films 0.8 mu m thick. The easy axis of the uni axial anisotropy was along the direction transverse to the rolling dir ection of the polymer web. The origin of the uniaxial anisotropy is th e anisotropic thermal shrinkage of the polymer web is discussed by a m odel.