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The FePt particles synthesized by polyoi process using tetraethylene glycol (TEG) as reducing agent at reaction temperatures 200 [degrees]C and 300 [degrees]C are superparamagnetic and ferromagnetic, respectively. The crystal structure of these particles is analyzed using XRD, XAS, and ASAXS to understand the formation of these particles at different heating temperatures. The results suggest that at 200 [degrees]C particles with Pt rich FePt core and amorphous shell rich in Fe are formed. However, when the reaction solution is annealed at 300 [degrees]C, sintering of several small particles occur. On the other hand, when hexachloroplatinum as nucleation control agent and a carboxylic acid as complex agent was added into the reaction solution, homogeneous alloy FePt particles with relatively large grain size of about 8 nm were obtained. In the process of forming the alloy nanoparticles, precipitated small particles were sintered at the amorphous interface and crystallization progresses along with ordering resulting in the formation of partially ordered ferromagnetic FePt. Index Terms--ASAXS, fcc-FePt, fct-FePt, polyol process, XAFS.

Perpendicular Co-Cr media were deposited on polyimide substrates by sputtering using an electron-cyclotron-resonance microwave plasma in an Ar sputtering gas pressure ranging from 3x[10.sup.-2] to 8x[10.sup.-2] Pa at a target to substrate distance from 170 to 230 mm. The accelerating voltage of the ions which bombard the media surface during deposition drastically affects the crystallographic and magnetic properties of Co-Cr films. Co-Cr media (50 nm in thickness) with good preferred crystal orientation ([Delta][[Theta].sub.50] less than 5 degrees), high perpendicular magnetic anisotropy ([H.sub.k] higher than 4 kOe), high perpendicular coercivity ([H.sub.c[perpendicular]] over 1400 Oe) and no initial layer were successfully deposited when the ion accelerating voltage was reduced less than about 20 V.