Thin film magnetic head
A thin film magnetic head includes a three-step configuration including deep and shallow groove surfaces, a super shallow groove surface, and an air bearing surface, and also, island-shaped center rail is provided in the center of the air outflow end of the disk-facing air bearing surface having a boundary on the surface of base alumina between a head element portion and a substrate, without including the surface of the substrate. Further, by providing in the surface of the substrate the super shallow groove surface shallower than a shallow groove surface, an alumina recession between the surface of the substrate and the head element portion, produced in a shallow dual step sub ambient slider, can be eliminated. Magnetic spacing between the head of the head element portion and the magnetic layer of the disk can be thereby reduced.
1. A thin film magnetic head comprising head element portion, an island-like center rail and an air inflow end rail, the head element portion including a write head element and a read head element provided over a substrate through a base alumina, a disk-facing surface side including surfaces of the substrate and the head element portion, the island-like center rail protruding from a deep groove surface arranged at a center of an air outflow end, the air inflow end rail protruding from the deep groove surface arranged at an air inflow end, the island-like center rail including a shallow groove surface protruding with a predetermined recession from the deep groove surface, and an air bearing surface protruding with a predetermined recession from the shallow groove surface,
wherein the air bearing surface of the island-like center rail is formed within a surface including the head element portion except for the substrate, and
wherein at least one super shallow groove surface is provided between the air bearing surface and the shallow groove surface, the super shallow groove surface having a recession from the air bearing surface smaller than a recession to the shallow groove surface.
2. The thin film magnetic head according to claim 1 , wherein a boundary between the air bearing surface and the super shallow groove surface is arranged on a region of the base alumina.
3. The thin film magnetic head according to claim 1 , wherein an air bearing surface overcoat is provided over the air bearing surface of the island-like center rail.
4. A thin film magnetic head comprising a head element portion, a center rail, and an air inflow end rail, the head element portion comprising a write head element and a read head element provided over a substrate through base alumina, the center rail protruding from a deep groove surface in a form of an island and being provided in a center of an air outflow end of a disk-facing surface including a surface of the substrate and a surface of the head element portion, the air inflow end rail protruding from the deep groove surface in the form of an island and being provided at an air inflow end of the disk-facing surface, the center rail and the air inflow rail each including a shallow groove surface protruding from the deep groove surface by a predetermined height and an air bearing surface protruding from the shallow groove surface by a predetermined height, the surface of the head element portion being included in the air bearing surface of the center rail,
wherein an air bearing surface overcoat is provided over a region of the air bearing surface of the center rail, the region including the surface of the head element portion, and a boundary of the air bearing surface overcoat is positioned on the base alumina between the head element portion and the substrate.
5. The thin film magnetic head according to claim 4 , wherein a surface of the air bearing surface overcoat at least formed on the base alumina protrudes from the surface of the substrate.
6. The thin film magnetic head according to claim 1 , wherein the write head element is an inductive magnetic head and the read head element is a magneto-resistance effect type head.
7. The thin film magnetic head according to claim 4 , wherein the write head element is an inductive magnetic head and the read head element is a magneto-resistance effect type head.
8. A thin film magnetic head comprising:
a substrate;
a head element portion including a write head element and a read head element, provided over the substrate through a base alumina;
a disk-facing surface including a surface of the substrate and a surface of the head element portion;
a center rail protruding from a deep groove surface, in a form of an island, and being provided at a center of an air outflow end of the disk-facing surface;
an air inflow end rail protruding from the deep groove surface, in the form of an island, and being provided at an air inflow end of the disk-facing surface,
wherein the center rail and the air inflow rail each includes a shallow groove surface protruding from the deep groove surface by a predetermined height and an air bearing surface protruding from the shallow groove surface by a predetermined height, the surface of the head element portion being included in the air bearing surface of the center rail,
wherein an air bearing surface overcoat is provided over a region of the air bearing surface of the center rail, and a region including the surface of the head element portion, and
wherein a boundary of the air bearing surface overcoat is positioned on the base alumina between the head element portion and the substrate.
9. The thin film magnetic head according to claim 8 , wherein a surface of the air bearing surface overcoat at least formed on the base alumina protrudes from the surface of the substrate.
10. The thin film magnetic head according to claim 8 , wherein the write head element is an inductive magnetic head and the read head element is a magneto-resistance effect type head.