Baseline popping of spin-valve recording heads induced by ESD

We report a novel mechanism of baseline popping (BLP) of spin-valve (SV) magnetic recording heads induced by machine model (MM) ESD, which is characterized by short transient time (10-20 ns) and high peak current (25-35 mA). Energy required for the phenomenon is just 0.2-0.3 nJ which is significantly less than that required for pinned layer reversal induced by human body model (HBM) ESD (Takahashi et al., 1998). Our data shows that this magnetic instability is caused by a change in the magnetization state of the permanent magnetic layer near track edges and can be eliminated by magnetic field re-initialization.