Stepped main pole for perpendicular write heads in hard disk drives and method of making same

Abstract

A stepped main pole for a perpendicular write head and methods of making the stepped main pole. The stepped main pole has a main pole tip and a base portion. The main pole tip has a surface that forms part of the ABS and a first thickness. The base portion extends from the main pole tip and has a thickness that varies from the first thickness to a second thickness to form a slanted surface with an apex angle adjacent the main pole tip. By placing the base portion away from the ABS and providing a thickness that increases in a direction away from the ABS, the stepped pole can provide the necessary magnetic flux for writing, while avoiding undesired leakage and fringing. To form embodiments of the stepped main pole of the invention, a fluorine-based reactive ion etch (RIE) may be used. By using an RIE to define the stepped main pole, the apex angle can be better controlled and tight edge control can be achieved.