Magnetic head manufacturing method forming sensor side wall film by over-etching magnetic shield
According to one embodiment, a magnetic head includes a reproducing unit to detect a medium magnetic field recorded in a magnetic recording medium. The reproducing unit includes first and second magnetic shields, a stacked body, and a side wall film. The stacked body is provided between the first and second magnetic shields and includes first and second magnetic layer and an intermediate layer provided between them. The stacked body has a side wall. The side wall intersects a plane perpendicular to a stacking direction from the first magnetic shield toward the second magnetic shield. The side wall film covers at least a part of the side wall of the stacked body. The side wall film includes at least one of Fe and Co, and has a composition different from a composition of the first magnetic layer and different from a composition of the second magnetic layer.
1. A method for manufacturing a magnetic head, the method comprising:
forming a stacked film on a first magnetic shield including at least one of Fe and Co, the stacked film being configured to form a stacked body, the stacked body including a first magnetic layer, a second magnetic layer, and an intermediate layer provided between the first magnetic layer and the second magnetic layer;
forming the stacked body by removing a part of the stacked film by etching;
forming a side wall film by over-etching the first magnetic shield to cause a material included in the first magnetic shield to adhere to a side wall of the stacked body, the side wall film including at least one of Fe and Co and having a composition different from a composition of the first magnetic layer and different from a composition of the second magnetic layer; and
forming a second magnetic shield on the stacked body to form a reproducing unit.
2. The method according to claim 1 , wherein the side wall film includes at least one of oxygen, nitrogen, and carbon.
3. The method according to claim 1 , wherein the side wall film includes a compound including at least one of oxygen, nitrogen, and carbon.
4. The method according to claim 1 , wherein the side wall film includes an oxide including at least one of oxygen, nitrogen, and carbon.
5. The method according to claim 1 , wherein the side wall film is electrically non-conductive.
6. The method according to claim 1 , wherein a thickness of the side wall film is not less than a thickness of a one-atom layer and not more than 5 nm.
7. The method according to claim 1 , wherein at least one of the first magnetic shield and the second magnetic shield includes at least one of CoFeAlSi, CoFeMnGe, FeCoGe, FeCoGa, FeCoSi, and FeCoAl.
8. The method according to claim 1 , wherein
the first magnetic layer is disposed between the first magnetic shield and the intermediate layer.
9. The method according to claim 1 , wherein
the side wall film includes at least one element selected from oxygen, nitrogen, and carbon, and
the element is introduced from a resist material used as a mask used in one of the etching and over-etching.
10. The method according to claim 1 , wherein one of the etching and over-etching is performed by using a gas including nitrogen gas.
11. The method according to claim 1 , wherein
the stacked body has an air bearing surface and an opposite surface opposite to the air bearing surface,
the forming the side wall film includes forming a back-side side wall film on the opposite surface by the over-etching the first magnetic shield, and
the back-side side wall film includes the at least one of Fe and Co and has a composition different from the composition of the first magnetic layer and different from the composition of the second magnetic layer.
12. The method according to claim 11 , wherein the back-side side wall film includes at least one of oxygen, nitrogen, and carbon.
13. The method according to claim 11 , wherein the back-side side wall film includes a compound including at least one of oxygen, nitrogen, and carbon.
14. The method according to claim 11 , wherein the back-side side wall film includes an oxide including at least one of oxygen, nitrogen, and carbon.
15. The method according to claim 11 , wherein the back-side side wall film is electrically non-conductive.
16. The method according to claim 11 , wherein a thickness of the back-side side wall film is not less than a thickness of a one-atom layer and not more than 5 nm.