Modeling of Temperature Rise in Giant Magnetoresistive (GMR) Sensor During an Electrostatic Discharge (ESD) Event

With the further miniaturization of the GMR heads, the electrostatic discharge (ESD) failure has become the primary reliability issue in manufacturing of these sensors. The Joule heating effect during the ESD events result in both thermal and magnetic damages in GMR heads. In this paper, the thermal response of the GMR read head to the excessive current/voltage during an ESD event is investigated numerically using a 3-D finite element analysis. Unlike the previous studies, the thermal properties of the GMR and Al₂O₃ gap layers used in the simulation are the experimentally measured values. The temperature-rise in GMR heads under human-body-model (HBM) source current is obtained for a range of GMR dimensions and thermal properties of its constituent materials. The simulation results show that temperature in the GMR element sharply increases as the GMR dimensions are reduced, indicating the future GMR heads are more susceptible to the ESD damages. In addition, thermal properties of the GMR and gap materials play key roles in accurate prediction of the temperature field in GMR head during ESD events.