Perpendicular magnetic recording head and method for production thereof
AssigneeHitachi Global Storage Technologies
InventorsTomohiro Okada, Masafumi Mochizuki, Hisashi Kimura, Wataru Kimura
Life of this patent
Estimating the term…
Abstract
Embodiments of the invention provide a perpendicular magnetic recording head that causes the difference between a physical track width and an effective track width to be small. Sides of a main pole are made concave with the concave vertex on each side located close to a trailing edge of the main pole.
Claims22
A perpendicular magnetic recording head comprising a read head which has a magneto-resistive sensor and a write head which has a main pole and a return pole,
- wherein each side in a cross track direction of the main pole is inwardly concave, and
- wherein an inequality of the form a <h/3, where “a” is a distance between a trailing edge and a concave vertex of the each side and h is a distance between the trailing edge and a leading edge, is satisfied.
A hard disk drive comprising a magnetic medium, a motor to rotatingly drive the magnetic medium, a magnetic head to write and read information on and from the magnetic medium, and a head driving section to drive the magnetic head in the radial direction of the magnetic medium,
- wherein the magnetic head comprises a read head which has a magneto-resistive sensor and a write head which has a main pole and a return pole, each side in a cross track direction of the main pole being inwardly concave and an inequality of the form a <h/3, where “a” is a distance between a trailing edge and a concave vertex of the each side of the main pole and h is a distance between the trailing edge and a leading edge of the main pole, being satisfied.
A method for production of a perpendicular magnetic recording head, the perpendicular magnetic recording head comprising a read head which has a magneto-resistive sensor and a write head which has a main pole and a return pole, each side in a cross track direction of the main pole being inwardly concave and an inequality of the form a <h/3, where “a” is a distance between a trailing edge and a concave vertex of the each side of the main pole and h is a distance between the trailing edge and a leading edge of the main pole, being satisfied, wherein the method comprises:
- forming a magnetic film to be the main pole;
- forming a mask pattern on the magnetic film;
- first milling in which a portion to be the main pole of the magnetic film is processed by ion milling with an ion incident angle with respect to a circumferential direction limited so that the portion has a rectangular sectional shape;
- second milling in which the portion to be the main pole of the magnetic film is processed by ion milling with the ion incident angle with respect to the circumferential direction limited and an ion incident angle with respect to a normal to the magnetic film being larger than in the first milling so that the portion has an inverted trapezoidal section;
- and
- third milling in which a side wall of the inverted trapezoidal is concaved by ion milling without the ion incident angle with respect to the circumferential direction limited.
A perpendicular magnetic recording head with a main pole tip having a cross section at an air bearing surface comprising:
- a substantially rectangular lower portion adjacent at a leading edge;
- a substantially trapezoidal upper portion having a leading and trailing parallel sides, wherein the trailing side is wider than the leading side, and wherein the leading side is substantially coincident with a trailing side of the rectangular lower portion.
Dependencies are inferred from the claim text.