Scanning magneto-resistance microscopy with FIB trimmed yoke-type magneto-resistive tape heads

Scanning magneto-resistance microscopy has been performed with thin film yo ke-type magneto-resistive tape heads possessing eight channels. The read fl ux guides of these channels have been trimmed down from 24 mum to widths va rying between 5.5 mum and 148 nm by focused ion beam milling with Ga+ ions. Tracks written on ME tape with an untrimmed write channel have been succes sfully imaged with all the trimmed channels. A significant attenuation (>5% ) of read-back voltage across the MR sensor is only observed for channels p ossessing flux guides trimmed by 77% to 5.5 mum. A 52% (similar to6 dB) dro p in read-back voltage is observed for a channel possessing a flux guide tr immed by 99.4% to 148 nm. (C) 2001 Elsevier Science B.V. All rights reserve d.