AN ADVANCED MAGNETO-RESISTIVE HEAD WITH A NEWLY DEVELOPED ELECTROPLATED HIGH-B-S WRITE POLE

A Magneto-Resistive (MR) head with a newly developed electroplated hig h-B-s CoNiFe write pole has been developed for use in Hard Disk Drives (HDDs). The electroplated film has the leading high saturation magnet ization (B-s) of 2.1 T to provide a soft magnetic film suitable for th e write element in MR heads. Introducing high-B-s films for the write- pole improves overwrite performance in 2,950 Oe high-H-c media by 17.7 dB. For the read element, a large exchange coupling NiMn film has bee n developed. This film provides an excellent biasing scheme for fabric ating abutted junction structure and the overlay structure. Signal sta bility evaluated by maximum asymmetry change during repeated read/writ e operations is improved by optimizing the write-core design and the m agnetostriction of the magnetic layers as well as by optimizing the bi asing scheme. Altitude sensitivity, which is defined as the change in flying height when atmospheric pressure is reduced from 1.0 to 0.7 atm , is suppressed from 11 to 5 nm by modifying the ABS (Air-Bearing Surf ace) design to increase the negative pressure induced. Typical read/wr ite characteristics of MR heads with high-B-s write-pole designed for 2.6 Gb/in(2) areal-density recording are described. An output-signal v oltage of 400 mu V/mu m with excellent signal stability has been obtai ned.