COMPARATIVE EXPERIMENTAL-STUDY OF EXCHANGE BIASED SYMMETRICAL AND ANTISYMMETRIC DUAL MAGNETORESISTIVE READ ELEMENTS

In this work, the advantage of the antisymmetric dual magnetoresistive head (A-DMR) in comparison to the symmetric design (S-DMR), in terms of common mode longitudinal field rejection is demonstrated experiment ally. The experiments were conducted at the wafer level. Magnetoresist ive hysteresis loops of heads with the top permalloy longitudinally bi ased by TbCo exchange tabs, defined either by an ion-milling process o r by lift-off are presented. Initialization methods to have the symmet ric or the antisymmetric state at low longitudinal applied magnetic fi elds are described.