Fabrication and Magnetic Properties of the B-Doped FePt Based Nano-composite Films

A series of B-doped FePt based nano-composite films were fabricated and the thickness of B layer was controlled after Fe/Pt ratio determined.First of all,interlayer method and underlayer method and their different combination method to were used fabricate the B-doped samples and effects of B-doping and annalling temperature on the magnetic properties of FePt multilayer samples were researched.Secondly,a series of B-doped FePt based nano-composite films with different B layer thickness were prepared using the interlayer doping method.The samples were measured to study the effect of different B-Doping concentration on the internal phase and annealing temperature of the FePt multilayer samples by X-ray diffraction(XRD),vibrating sample magnetometer,etc.Experiment results shows that after the doping of the B-layer,the coercivity of the FePt multilayer samples was appearently improved,and became perpendicular orientation.Along with thickness increases of the doped layer,FePtB multilayer sample ordering phase transitions became more fully and the FePt grain size of the sample have also been effectively controlled.When the B-layer was 14nm,FePtB multilayer samples had good characteristics of the perpendicular orientation.In addition,B-layer doped to the FePt multilayer films could reduce the annealing temperature.