Electrostatic discharge sensitivity of giant magnetoresistive recording heads

In this article electrostatic discharge (ESD) damage to giant magnetoresistive (GMR) recording heads is studied for the first time. The ESD failure threshold was measured using an extremely short duration (1 ns) metal contact ESD transient. The failure energy required to melt the GMR recording head was 2.3 nJ, about half of the 5 nJ of energy needed to melt a conventional anisotropic magnetoresistive (AMR) head design. Scanning electron microscope scans of ESD damaged AMR and GMR heads show localized melting of the sensors. It is concluded that recording heads with GMR sensors, planned for use in the near future, will have significantly lower ESD failure thresholds than AMR recording heads in use today. Finally, scaling arguments show that an AMR head design with the same reduced cross-sectional area of the GMR head has a comparable ESD failure threshold.