MAGNETORESISTIVE SENSOR WTIH A SOFT ADJACENT LAYER HAVING HIGH MAGNETIZATION, HIGH RESISTIVITY, LOW INTRINSIC ANISOTROPY AND NEAR ZERO MAGNETOSTRICTION

摘要

A soft adjacent layer with high magnetization, high resistivity, low corrosion and near zero magnetic strain is provided for the magnetoresistive sensor of the read head. The magnetoresistive sensor may be either an anisotropic magnetoresistive sensor or a spin valve sensor. In both sensors, the soft adjacent layer is CoHfNb or CoHfNbFe. Hf is added to reduce corrosion, and Hf and Nb are balanced to provide near zero magnetization. The addition of Fe can increase the reduction of negative magnetostriction without weakening the magnetization of the alloy. Since CoHfNb has much higher magnetization than NiFeCr, soft adjacent layers made of CoHfNb can be made thinner than soft adjacent layers made of NiFeCr, resulting in higher resistance of the soft adjacent layers. The higher the resistance of the soft adjacent layer, the smaller the shunting of the sense current through the soft adjacent layer, and the better the signal performance of the magnetoresistive readhead.