Method of forming a pole tip region in a main pole layer of a perpendicular magnetic recording (PMR) write head

摘要

A main pole layer is deposited within an opening in a patterned photoresist layer on a substrate. The photoresist is thinned to expose an upper portion of a pole tip region that is then trimmed to a rectangular shape while a lower portion retains an inverted trapezoidal shape. Thereafter, a second trimming process forms a pole tip with a first width in the upper rectangular portion and a second thickness and second width which is less than the first width in the lower portion. A CMP step subsequently thins the upper portion to a first thickness of 0.04 to 0.08 microns while the second thickness remains at 0.16 to 0.32 microns. The bottom surface of the lower portion along the ABS becomes the trailing edge in a recording operation. The pole tip has a consistent first width (track width) that is not influenced by CMP process variations.