Magnetic structure including two ferromagnetically coupled magnetic layers and method of manufacturing same

1. A magnetic structure comprising:

a first magnetic layer having a top surface;

a nonmagnetic insulating layer having a top surface, the nonmagnetic insulating layer being adjacent to the first magnetic layer without overlapping the top surface of the first magnetic layer;

a nonmagnetic adhesion layer disposed on the top surfaces of the first magnetic layer and the nonmagnetic insulating layer; and

a second magnetic layer disposed on the nonmagnetic adhesion layer, the second magnetic layer being in direct contact with the nonmagnetic adhesion layer, wherein:

the nonmagnetic insulating layer contains an oxygen atom;

the nonmagnetic adhesion layer is composed of one element or a plurality of elements selected from the group consisting of Al, Si and nonmagnetic transition metal elements except Ru, and a bond enthalpy of a diatomic molecule composed of an atom of the one element or each of the plurality of elements and an oxygen atom is 400 kJ/mol or higher;

the nonmagnetic adhesion layer has a thickness within a range of 0.3 to 0.8 nm; and

the first magnetic layer and the second magnetic layer are ferromagnetically coupled to each other.

2. The magnetic structure according to claim 1 , further comprising a third magnetic layer disposed on the second magnetic layer.

3. The magnetic structure according to claim 1 , being for use in a magnetic head.

4. A magnetic structure comprising:

a first magnetic layer having a top surface;

a nonmagnetic insulating layer having a top surface, the nonmagnetic insulating layer being disposed to cover a portion of the top surface of the first magnetic layer;

a nonmagnetic adhesion layer disposed on the top surfaces of the first magnetic layer and the nonmagnetic insulating layer; and

a second magnetic layer disposed on the nonmagnetic adhesion layer, the second magnetic layer being in direct contact with the nonmagnetic adhesion layer, wherein:

the nonmagnetic insulating layer contains an oxygen atom;

the nonmagnetic adhesion layer is composed of one element or a plurality of elements selected from the group consisting of Al, Si and nonmagnetic transition metal elements except Ru, and a bond enthalpy of a diatomic molecule composed of an atom of the one element or each of the plurality of elements and an oxygen atom is 400 kJ/mol or higher;

the nonmagnetic adhesion layer has a thickness within a range of 0.3 to 0.8 nm; and

the first magnetic layer and the second magnetic layer are ferromagnetically coupled to each other.

5. The magnetic structure according to claim 4 , further comprising a third magnetic layer disposed on the second magnetic layer.

6. The magnetic structure according to claim 4 , being for use in a magnetic head.

7. A method of manufacturing a magnetic structure, the magnetic structure comprising: a first magnetic layer having a top surface; a nonmagnetic insulating layer having a top surface, the nonmagnetic insulating layer being adjacent to the first magnetic layer without overlapping the top surface of the first magnetic layer; a nonmagnetic adhesion layer disposed on the top surfaces of the first magnetic layer and the nonmagnetic insulating layer; and a second magnetic layer disposed on the nonmagnetic adhesion layer,

the method comprising the steps of:

forming the first magnetic layer and the nonmagnetic insulating layer;

forming the nonmagnetic adhesion layer on the top surfaces of the first magnetic layer and the nonmagnetic insulating layer; and

forming the second magnetic layer on the nonmagnetic adhesion layer, the second magnetic layer being in direct contact with the nonmagnetic adhesion layer, wherein:

the nonmagnetic insulating layer contains an oxygen atom;

the nonmagnetic adhesion layer is composed of one element or a plurality of elements selected from the group consisting of Al, Si and nonmagnetic transition metal elements except Ru, and a bond enthalpy of a diatomic molecule composed of an atom of the one element or each of the plurality of elements and an oxygen atom is 400 kJ/mol or higher;

the nonmagnetic adhesion layer has a thickness within a range of 0.3 to 0.8 nm; and

the first magnetic layer and the second magnetic layer are ferromagnetically coupled to each other.

8. The method of manufacturing the magnetic structure according to claim 7 , wherein the nonmagnetic adhesion layer and the second magnetic layer are formed successively in a vacuum.

9. The method of manufacturing the magnetic structure according to claim 7 , further comprising the step of forming a third magnetic layer on the second magnetic layer.

10. The method of manufacturing the magnetic structure according to claim 9 , wherein the third magnetic layer is formed by plating.

11. A method of manufacturing a magnetic structure, the magnetic structure comprising: a first magnetic layer having a top surface; a nonmagnetic insulating layer having a top surface, the nonmagnetic insulating layer being disposed to cover a portion of the top surface of the first magnetic layer; a nonmagnetic adhesion layer disposed on the top surfaces of the first magnetic layer and the nonmagnetic insulating layer; and a second magnetic layer disposed on the nonmagnetic adhesion layer,

the method comprising the steps of:

forming the first magnetic layer;

forming the nonmagnetic insulating layer;

forming the nonmagnetic adhesion layer on the top surfaces of the first magnetic layer and the nonmagnetic insulating layer; and

forming the second magnetic layer on the nonmagnetic adhesion layer, the second magnetic layer being in direct contact with the nonmagnetic adhesion layer, wherein:

the nonmagnetic insulating layer contains an oxygen atom;

the nonmagnetic adhesion layer is composed of one element or a plurality of elements selected from the group consisting of Al, Si and nonmagnetic transition metal elements except Ru, and a bond enthalpy of a diatomic molecule composed of an atom of the one element or each of the plurality of elements and an oxygen atom is 400 kJ/mol or higher;

the nonmagnetic adhesion layer has a thickness within a range of 0.3 to 0.8 nm; and

the first magnetic layer and the second magnetic layer are ferromagnetically coupled to each other.

12. The method of manufacturing the magnetic structure according to claim 11 , wherein the nonmagnetic adhesion layer and the second magnetic layer are formed successively in a vacuum.

13. The method of manufacturing the magnetic structure according to claim 11 , further comprising the step of forming a third magnetic layer on the second magnetic layer.

14. The method of manufacturing the magnetic structure according to claim 13 , wherein the third magnetic layer is formed by plating.