Abstract: A method for trimming a pole used in a read-write head comprises the step of depositing a metallic layer on a layer of pole material, patterning the metallic layer so that it can serve as a mask, and ion beam etching the pole material with nitrogen ions. Of importance, a thin nitride layer forms on the metallic layer so that the etch rate of the metallic layer during ion beam etching is slowed. Alternatively, in lieu of the metallic layer, a nitride layer can be used.

Abstract: A low fringe-field and narrow write-track magnetic read-write head. The low fringe-field and narrow write-track magnetic read-write head includes a first pole layer formed adjoining an insulator layer over a substrate. The first pole layer has a first air bearing surface which has a first edge adjoining and parallel with a first surface of the insulator layer. The low fringe-field and narrow write-track magnetic read-write head also includes a second pole layer separated from the first pole layer by the insulator layer. The second pole layer has a width no greater than about 20 microns and a width no greater than about 100 percent of the width of the first pole layer where the width of the second pole layer is contained within the width of the first pole layer. The second pole layer also has a second air bearing surface coplanar with the first air bearing surface.