Cu (ti) / Cocrpt / Cu (ti) Preparation Of The Nanoparticle Film, The Micro-structure And Magnetic Properties,

The research of magnetic granular films is the focus in magnetism field. The achievement was not only applied to the fields of magnetic recording and sensors etc, but also perfected the theory of micromagnetism. Five series granular films were prepared by rf and dc magnetron sputtering onto glass substrates at room temperature. The microstructures of films were examined by X-ray diffraction (XRD). The morphologies and domain structures were observed by scanning probe microscope (SPM). And magnetic properties were measured by vibrating sample magnetometer (VSM).X-ray diffraction profiles show that the CoCrPt magnetic layers are formed as the hexagonal-close-packed (HCP) structure. All samples show a strong perpendicular anisotropy.It has been found that the microstructure and magnetic properties of Cu/CoCrPt/Cu films depend strongly on the Cu overlayer thickness and the magnetic layer thickness. VSM measurements indicate that the out-of-plane coercivity reaches the maximum 1775 Oe and AFM images show the minimum average grain size = 7.8 nm just at 11 nm Cu overlayer thickness. And the out-of-plane coercivity reaches the maximum 1842 Oe, the minimum average grain size = 6.9 nm just when the thickness of magnetic layer is 35 nm.For series of Ti (x = 0, 5, 10, 15, 20, 30 nm) /CoCrPt (30 nm) /Ti (30 nm) films, VSM measurements indicate that the out-of-plane coercivity reaches the maximum 1675.5 Oe, AFM images show the minimum average grain size = 7.2 nm and MFM images show that the minimum average magnetic cluster size is estimated to be about 6.4 nm just at x = 5 nm.It has been found that the microstructure and magnetic properties of C/CoCrPt/Ti films depend strongly on the postannealing temperature and C overlayer thickness. VSM measurements indicate that the out-of-plane coercivity reaches the maximum 1648 Oe, AFM images show the minimum average grain size = 9.6 nm just postannealed at T_a = 300 ℃. From switching field distribution (SFD) measurements, we conclude that more C atoms are segregated into the grain boundaries and thus decrease the intergrain interaction so as to improve the properties of the magnetic films.