摘要 |
In a MR head of the non-shunt bias type, one or more extremely thin coatings of a sacrificial conductive material are applied on the magnetoresistive strip, each such coating being so thin that it has extremely high sheet resistance in comparison to the sheet resistance of the MR strip. Because the sacrificial coating(s) is (are) in direct contact with the MR strip, the requirement for electrical conductivity between the coating(s) and the MR strip is (are) met; and because the sacrificial coating(s) is (are) of high resistivity, very little sense current is sapped away from the MR strip by the sacrificial coating(s), with attendantly very little decrease in the sensitivity of the head. By sandwiching the MR strip between equi-thick sacrificial coatings, whatever leakage currents flow through the high resistivity sacrificial coatings are productive of equal and opposite biasing effects vis-a-vis the MR strip, i.e. the sacrificial coatings produce no net bias field and are magnetically transparent to the MR strip.
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