Magnetic anisotropy of L11-type (Co1-XMX)50Pt50 (M:Ni, Fe, Cr, Mn) and Co50(Pt1-XPdX)50 ordered alloy perpendicular films

We substituted 3d transition elements M (M=Ni, Fe, Cr, and Mn) for some of the Co, or Pd for some of the Pt, in L1(1)-type Co50Pt50 ordered alloy perpendicular films, and studied magnetic and structural properties. Films were fabricated at a substrate temperature of 360 degrees C using ultra-high vacuum (UHV) sputter film deposition. The order parameter S was almost a constant of about 0.5 when Ni was substituted for some of the Co. The uniaxial magnetic anisotropy K-u and the saturation magnetization, M-s, decreased as the Ni content increased, however, K-u maintained a relatively large value of 1.8x10(7) erg/cm(3) (M-s=570 emu/cm(3)) even for a Co20Ni30Pt50 composition. In the substitutions of Fe for some of the Co, or Pd for some of the Pt, no significant variation in M-s was observed, however, the rate of decrease of K-u on increasing the Fe or Pd content was larger than when Ni was substituted. The substitution of Cr or Mn for some Co resulted in significant reductions in S, M-s and K-u. Experimental results showed the potential of Co-Ni-Pt ordered films for use in data storage applications, due to their very high K-u potential, relatively low M-s, the relatively low fabrication temperature, and good controllability of the grain orientation.