| The rapld development of our informational society urgently requires theappearance of new matenals for high-density recording Although Co(1-x)Ptx Alloy filmshas caused much attention of material and physics scientists for their chemicalstability ease for fabrication, higher perpendicular magnetic anisotropy (PMA,0 4～2MJ/m3) and larger Kerr rotation angle at short wavelength, their relative higherCurie temperature (Tc) seriously affected the application In order to find a kind ofmaterial with lower Tc, good magnetic and magneto-optical properties, we fabricatedPtCoNi alloy films by DC sputtering method There are two methods for adding Ni toPt3CoOne way is to paste the small Ni chips on Pt3Co target Results show that lowerTc (=242℃), higher PMA(Ku～0 5MJ/m3, Hc～280KA/m, squreness～1) and higherKerr rotation angle(0 48°)can be obtained in (Pt3Co)1-xNix alloy films by sultable Ni(x=0 43) additionThe other way is to paste small Ni and Co chips on the pure Pt target Resultsshow that although Ni addition greatly reduces TC of Pt3(Co1-xNix) alloy films, itaffects the PMA and higher Kerr rotation angle The sultable Ni content is 0 4, thecorresponding value of Tc is 200℃, which is much lower than that of Pt3Co alloy film(272℃)Due to the lower and more adjustable Tc, we select Pt3(Co1-xNix (x=0 4) alloyfilms for investigating the effects of Ar pressure, film thickness and substratetemperature upon the smicfure, magnetic and magneto-optical properties The resultsshow that 1), higher Ar pressure will benefit the formation of higher PMA and largemagneto-optical properties The best Ar pressure range is(15～20Pa, 2), the best filmthickness ls 60nm, 3), the best substrate temperatUre range IS 240280oC forobtalmng good PMA and magneto-optlcaI propertlesThe best magnet1c and magneto-optlcal propertIes of Pt,(Co,-xNlJ(x=0 4) alloyfilms are coerclvIty Hc305KA/m, PMA Ku0 4MJ/m', remanencel, Tc200'C,Kerr rotat1on angle at short wavelength 0 45' These results lndlcate that Pt,(Co,-xNl.)(x==0 4) alloy film may be the replacement of TbFeCo film wh1ch ls now ln useThe ongln of PMA of magnetlc films 1s also one of the heat polnt dlscussed bysclentlst Here, based on the PtCoNl alloy films, we wlll dlscuss 1tX-ray dlmactlon and the magnetlc measurement results show that, with thelncrease of AI pressure, texttire of Pt3(Co,-xNl.)(x=0 4) alloy film decreases,while PMA lncreases Therefore lt ls concluded that textufC ls not the malnreason for PMAAccordlng to the theory of anlsotropy 1nduced by stress, the PMA ls proportlonalto the dlfference betWCen substrae and amblent temperature, but our exper1mentalresults show that the largest PMA only aPpears at certaln substrate temPeateTherefore, the PMA of the Pt,(Co,-xNlJ(x=0 4) alloy film was not lnduced by stressBased on our expenmental data and by comparing the dlfferent explanatlon ofPMA of Pt,Co, PtCo and PtCo, alloy films, we assume that the ongln may becorrelated to the locally ordered phase ln the d1sordered PtCoNl alloy films, thls lQndof order IS charactenzed by nch N1, nch Co or nch CoNl buned ln PtCoNl alloyfilmsFlnally, we provlded a new method for magneto-optlcal muItllayer deslgn Newmethod take lnto consIderat1on not only thermal and optlcal reqluements, but also theneed of servo (reflectlvlty of 2030%) The results show that new method ls morereasonable and slmple ln calculatlon...
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