Method of manufacturing a magnetic head
View Patent ↗A magnetic head suitable for high-density recording is provided at a high yield by a method that suppresses a reduction in reproducing output signal due to ion-beam irradiation. After an air-bearing surface of a read element, a magnetic-head element, or a row bar is mechanically polished, the air-bearing surface is irradiated with an ion beam, such that an orthographic projection of an ion-beam incidence direction onto the air-bearing surface forms an in-plane incidence angle of 30 degrees to 150 degrees or of 210 degrees to 330 degrees with respect to a track-width direction. Thereby, the formation of a short circuit due to ion-beam irradiation may be hindered.
1. A method of manufacturing a magnetic head comprising a read element including a magnetoresistive film, said method comprising:
a) mechanically polishing an air-bearing surface of the read element; and
b) irradiating the mechanically polished air-bearing surface of the read element with an ion beam, such that an in-plane incidence angle, formed by an orthographic projection of an ion-beam incidence direction onto the air-bearing surface of the read element and by a track-width direction of the magnetic head, is only of 30 degrees to 150 degrees or of 210 degrees to 330 degrees.
2. The method of claim 1 , wherein the magnetic head is rotated about a normal to a surface of the magnetic head, such that the in-plane incidence angle oscillates only between 30 degrees and 150 degrees or between 210 degrees and 330 degrees, while the air-bearing surface of the read element is irradiated with the ion beam.
3. The method of claim 1 , wherein the magnetic head is rotated about a normal to a surface of the magnetic head, and the air-bearing surface of the read element is irradiated with the ion beam only when the in-plane incidence angle is of 30 degrees to 150 degrees or of 210 degrees to 330 degrees.
4. The method of claim 1 , further comprising, prior to b), irradiating the air-bearing surface of the read element with the ion beam, while the magnetic head is rotated about a normal to a surface of the magnetic head.
5. The method of claim 1 , wherein an out-of-plane incidence angle, formed by the ion-beam incidence direction and by a normal to a surface of the magnetic head, is of 40 degrees to 88 degrees.
6. A method of manufacturing a plurality of magnetic heads, comprising:
a) forming a plurality of magnetic-head elements on a wafer, each magnetic-head element comprising a read element including a magnetoresistive film;
b) cutting the wafer into row bars, each row bar comprising a respective plurality of magnetic-head elements in a row;
c) mechanically polishing an air-bearing surface of each row bar;
d) cleaning the mechanically polished air-bearing surface of each row bar by using a directional ion beam, including:
i) setting the row bars on a pallet, such that the magnetic-head elements are parallel or antiparallel to one another in a track-width direction of the magnetic-head elements, and
ii) irradiating the air-bearing surface of each row bar with the ion beam, such that an in-plane incidence angle, formed by an orthographic projection of an ion-beam incidence direction onto the air-bearing surface of each row bar and by the track-width direction, is only of 30 degrees to 150 degrees or of 210 degrees to 330 degrees;
e) forming an air-bearing-surface protective film on the cleaned air-bearing surface of each row bar;
f) forming a rail, pads, and a deep groove on the air-bearing surface bearing the air-bearing-surface protective film of each row bar; and
g) cutting each row bar into the respective plurality of magnetic-head elements.
7. The method of claim 6 , wherein, in ii), the pallet is rotated about a normal to a surface of the pallet, such that the in-plane incidence angle oscillates only between 30 degrees and 150 degrees or between 210 degrees and 330 degrees, while the air-bearing surface of each row bar is irradiated with the ion beam.
8. The method of claim 6 , wherein, in ii), the pallet is rotated about a normal to a surface of the pallet, and the air-bearing surface of each row bar is irradiated with the ion beam only when the in-plane incidence angle is of 30 degrees to 150 degrees or of 210 degrees to 330 degrees.
9. The method of claim 6 , wherein d) further includes, prior to ii), irradiating the air-bearing surface of each row bar with the ion beam, while the pallet is rotated about a normal to a surface of the pallet.
10. The method of claim 6 , wherein an out-of-plane incidence angle, formed by the ion-beam incidence direction and by a normal to a surface of the pallet, is of 40 degrees to 88 degrees.
11. The method of claim 6 , wherein the magnetoresistive film comprises a tunnel barrier layer between a pinned ferromagnetic layer and a free ferromagnetic layer.
12. A method of manufacturing a plurality of magnetic heads, comprising:
a) forming a plurality of magnetic-head elements on a wafer, each magnetic-head element comprising a read element including a magnetoresistive film;
b) cutting the wafer into row bars, each row bar including a respective plurality of magnetic-head elements in a row;
c) mechanically polishing an air-bearing surface of each row bar;
d) cutting each row bar into the respective plurality of magnetic-head elements;
e) cleaning a mechanically polished air-bearing surface of each magnetic-head element by using a directional ion beam, including:
i) setting the magnetic-head elements on a pallet, such that the magnetic-head elements are parallel or antiparallel to one another in a track-width direction of the magnetic-head elements, and
ii) irradiating the air-bearing surface of each magnetic-head element with the ion beam, such that an in-plane incidence angle, formed by an orthographic projection of an ion-beam incidence direction onto the air-bearing surface of each magnetic-head element and by the track-width direction, is only of 30 degrees to 150 degrees or of 210 degrees to 330 degrees;
f) forming an air-bearing-surface protective film on the cleaned air-bearing surface of each magnetic-head element; and
g) forming a rail, pads, and a deep groove on the air-bearing surface bearing the air-bearing-surface protective film of each magnetic-head element.
13. The method of claim 12 , wherein, in ii), the pallet is rotated about a normal to a surface of the pallet, such that the in-plane incidence angle oscillates only between 30 degrees and 150 degrees or between 210 degrees and 330 degrees, while the air-bearing surface of each row bar is irradiated with the ion beam.
14. The method of claim 12 , wherein, in ii), the pallet is rotated about a normal to a surface of the pallet, and the air-bearing surface of each magnetic-head element is irradiated with the ion beam only when the in-plane incidence angle is of 30 degrees to 150 degrees or of 210 degrees to 330 degrees.
15. The method of claim 12 , wherein e) further includes, prior to ii), irradiating the air-bearing surface of each magnetic-head element with the ion beam, while the pallet is rotated about a normal to a surface of the pallet.
16. The method of claim 12 , wherein an out-of-plane incidence angle, formed by the ion-beam incidence direction and by a normal to a surface of the pallet, is of 40 degrees to 88 degrees.