EFFECT OF SPUTTERING PRESSURE OF PD UNDERLAYER ON THE PERPENDICULAR MAGNETIC-ANISOTROPY IN CO PD MULTILAYERED THIN-FILMS/

The magnetic properties of Co/Pd multilayers, in particular the perpen dicular magnetic anisotropy, have been analyzed as a function of the s puttering pressure of Pd underlayer, With an increase of sputtering pr essure of the underlayer from 6 mTorr to 25 mTorr, perpendicular coerc ivity of the multilayers increased with a slight decrease of saturatio n magnetization, and the increment of the coercivity was larger for th e films with thinner cobalt layers, From the anisotropy analysis, it w as found that the interface anisotropy energy decreased from 0.390 erg /cm(2) to 0.255 erg/cm(2) because of the interface roughening of the m ultilayers, which was mainly responsible for the decrease of perpendic ular anisotropy, while the volume anisotropy energy increased from -11 .37x10(6) erg/cm(3) to -7.90x10(6) erg/cm(3). The abnormally large int rinsic volume anisotropy energies of the multilayers with thin cobalt layers(<7 Angstrom) appears to suggest the noticeable contribution of magnetoelastic effect to the perpendicular anisotropy of the films.