Limitations of the adiabatic model for ESD failure in GMR structures

Patterned giant magnetoresistance (GMR) films resembling shield-less sensors with varying sizes have been subjected to simulated ESD. As sensor width decreases, the failure voltage for a modified human body model (150 /spl Omega/, 150 pF) passes through a minimum before sharply increasing for narrowest devices. In contrast to adiabatic predictions, smaller width devices (<0.75 /spl mu/m) become more robust to ESD due to the thermal conductance of the sensor contacts. These results should extend to GMR heads, and suggest that for longer ESD events, changes in sensor width for higher areal density recording may partially mitigate the trend towards greater ESD sensitivity.