Effects of unbalanced ionizers on magnetoresistive recording heads

The purpose of this work is to study the effects of handling magnetoresistive (MR) recording heads near an unbalanced DC ionizer. A methodology for studying and measuring the charging and current transient behavior of an MR head as a function of ionizer imbalance is presented. SEM photographs of MR heads handled near an unbalanced ionizer show severe ESD damage of the MR sensor. A useful result is the measurement of the peak ESD current as a function of ionizer imbalance. It is concluded that DC ionizers must be properly maintained and carefully balanced in order to avoid harmful ESD currents in MR heads.