Franciscus Antonius Pronk

A Novel Concept in Thin Film Magnetic Heads: The Sensor Last Design

Almost all commercially available magnetic heads are constructed according the “sensor first design”. In this design at first the MR read-out sensor, based on a highly sensitive and thin permalloy layer, is processed. On top of the sensor the other parts of the head are processed. However, this concept has various drawbacks for the next generation of dataheads. The development of planarization in wafer processing technology opened the way to the sensor-last design. The solutions for these (and other) problem has resulted in a robust production process. The total oxide thickness was decreased from 40 μm down to 17 μm. The sensor last design is now successfully introduced in the manufacturing of the DIGAMAX™ system.