Magnetic write head having a stair notched, steep shouldered pole and a write gap bump

Abstract

A magnetic write head structure that maximizes write field strength while minimizing stray fields. The write pole structure maximizes write field strength by minimizing saturation of the magnetic pole tips, and minimizes stray field writing by preventing magnetic fields from extending laterally from the sides of the magnetic pole. The write head structure includes a write pole having a pole tip configured with a stair notched shape and a steep shouldered base beneath the stair notched portion. This configuration maximizes the amount of flux that can be delivered to the pole tip while also avoiding stray fields. The magnetic pole can also be configured with wing shaped extensions that extend laterally from the pole tip region but which are recessed from the ABS by a desired amount. The magnetic write head structure can be manufactured by forming a magnetic pole with a raised portion, depositing a write gap material over the magnetic pole and then forming a magnetic pedestal over the magnetic pole and write gap, the pedestal having a width significantly smaller than the width of the raised portion of the magnetic pole, a first ion mill can then be performed to notch and trim the magnetic pole. Then a non-magnetic layer such as alumina can be deposited and a second ion mill performed to form a stair notched configuration. An alumina bump can be formed prior to ion milling to provide a mask for forming the laterally extending, recessed wings in the pole tip of the magnetic pole.