Inverse effect of magnetostriction in yoke type MR heads

The authors investigated stress induced magnetic anisotropy in yoke type MR heads (YMRH). The distributions of the easy axis in YMRH were calculated from the result of a threo dimonsional stress analysis. When a sputtered NiFe film is used as the upper yoke, if the magnetostriction λs in the MR element is positive and the λs in the upper yoke is negative, the easy axis distribution is such that a stable MR response, can be obtained. We could explain the variations of MR responses as a function of the external stress with our result.