MAGNETIC-PROPERTIES AND STRUCTURES OF COCRTA FILMS FOR WIDE-RANGE OF CR VARIATION

We studied the effects of Ta addition on magnetic properties of CoCr films for a wider range of 13 - 21 at.%Cr and tried to elucidate how Ta addition increases the coercivity. Ta addition is effective in increasing perpendicular coercivity in the films with Cr content lower than 17 at%Cr region and is not effective in those with higher than 19 at.%Cr region. The higher coercivity of the CoCrTa films is interpreted as the enhanced Cr segregation behavior due to the difference of chemical affinity among the atoms. However, the lower coercivity of the films with large amount of Ta is attributed to the formation of the amorphous-like structure.