Process complexity of magnetoresistive sensors: a review

Magnetoresistive (MR) thin film sensors are presently used in a variety of hard disk and tape storage devices. Review papers have detailed the various methods and configurations required to linearize and stabilize the output signal characteristics of the MR thin film transducer. However, little emphasis has been placed on describing the complexity of such configurations with respect to materials and fabrication requirements. Specifically this review will examine MR sensor configurations from the perspective of the thin film processing technology required to implement the sensor design into a thin film head environment. The general trend is that the process complexity for MR sensors has increased in the areas of magnetic materials and patterning as the areal density performance of the sensor has improved.