Magnetic head for hard disk drive having varied composition nickel-iron alloy magnetic poles
AssigneeInternational Business Machines Corporation
InventorsThomas Edward Dinan, Neil Leslie Robertson, Alan Jun-Yuan Tam
Life of this patent
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Abstract
A magnetic head for a hard disk drive. The magnetic poles of the head are formed with a NiFe alloy having a graduated composition in which a higher Fe concentration is fabricated proximate the write gap layer between the magnetic poles. Each magnetic pole is fabricated in a single electroplating step in which the duty cycle of the electroplating current is altered during the electroplating operation. Where the duty cycle is greatest the Fe ion concentration is likewise greatest.
Claims14
A magnetic head including a write head, comprising:
- a first (P1) magnetic pole;
- a second (P2) magnetic pole;
- a write gap layer being disposed between said P1 magnetic pole and said P2 magnetic pole;
- at least one of said P1 magnetic pole and said P2 magnetic pole being composed of a NiFe ion composition, and wherein the ratio of Ni to Fe is graduated throughout portions of either of said P1 magnetic pole and said P2 magnetic pole;
- and
- wherein said P1 magnetic pole is formed with a first portion wherein the relative concentration of Ni and Fe is approximately constant and a second portion wherein the relative concentration of Ni and Fe ions is graduated.
A magnetic head including a write head, comprising:
- a first (P1) magnetic pole;
- a second (P2) magnetic pole;
- a write gap layer being disposed between said P1 magnetic pole and said P2 magnetic pole;
- at least one of said P1 magnetic pole and said P2 magnetic pole being composed of a NiFe ion composition, and wherein the ratio of Ni to Fe is graduated throughout portions of either of said P1 magnetic pole and said P2 magnetic pole;
- and
- wherein said P2 magnetic pole is formed with a first portion wherein the relative concentration of Ni and Fe is graduated, and a second portion wherein the relative concentration of Ni and Fe is approximately constant.
A magnetic head including a write head, comprising:
- a first (P1) magnetic pole being composed of a NiFe composition, wherein a portion of said P1 magnetic pole is formed with the relative concentration of Ni and Fe being approximately constant, and the ratio of Ni to Fe is graduated throughout other portions of said P1 magnetic pole;
- a second (P2) magnetic pole being composed of a NiFe composition, and wherein a portion of said P2 magnetic pole is formed with the relative concentration of Ni and Fe being approximately constant, and the ratio of Ni to Fe is graduated throughout other portions of said P2 magnetic pole;
- a write gap layer being disposed between said P1 magnetic pole and said P2 magnetic pole.
A hard disk drive including a magnetic head that includes a write head, comprising:
- a first (P1) magnetic pole being composed of a NiFe composition, wherein a portion of said P1 magnetic pole is formed with the relative concentration of Ni and Fe being approximately constant, and the ratio of Ni to Fe is graduated throughout other portions of said P1 magnetic pole;
- a second (P2) magnetic pole being composed of a NiFe composition, and wherein a portion of said P2 magnetic pole is formed with the relative concentration of Ni and Fe being approximately constant, and the ratio of Ni to Fe is graduated throughout other portions of said P2 magnetic pole;
- a write gap layer being disposed between said P1 magnetic pole and said P2 magnetic pole.
Dependencies are inferred from the claim text.