Patent attributes
A giant magnetoresistive (GMR) head is formed to include a recess in an overcoat layer that reduces stress on the poles. The process includes depositing a seed layer over the overcoat layer prior to plating a metal mask layer with an opening where the recess is to be formed, wet chemical etching the seed layer through the opening in the mask layer and performing an ion milling process to remove any remaining traces of the seed layer. With the seed layer completely removed, a trench having smooth sidewalls and bottom is etched in the overcast layer by a reactive ion etch (RIE) process. The saw that is used to separate the head elements in the wafer can be passed through the clean trench without contacting the overcoat layer, thereby avoiding the chipping and cracking that might otherwise result from the use of a silicon dioxide or silicon nitride overcoat layer.
