Dissipative Gap Material in Tape Heads

A giant magnetoresistive (GMR) head in tape-recording systems is affected by the electrostatic discharge (ESD) between the sensor and magnetic shields. Hence, Pt-doped Al
₂
O
₃
was developed as a dissipative gap material to reduce the ESD current. Pt chips were sputtered on an alumina target to vary the film resistance. The decay time of a charged plate on Pt-doped Al
₂
O
₃
was measured for various film thicknesses. The I-V characteristics indicated that, as the applied voltage increased, the Pt-doped Al
₂
O
₃
film increased the current gradually, whereas the Al
₂
O
₃
film increased the current rapidly over the breakdown voltage.