High frequency magnetic field assisted magnetic recording head, and method of manufacturing same
Provided are a structure of a high frequency magnetic field assisted magnetic recording head in which the positional relationship of a main magnetic pole and a spin torque oscillator in a cross-track direction is accurately determined, and in which variations are not caused in high frequency magnetic field assist characteristics, and a method of manufacturing the structure. The high frequency magnetic field assisted magnetic recording head includes a main magnetic pole, a spin torque oscillator disposed on the main magnetic pole, and an insulating side gap covering a side surface of the main magnetic pole and a side surface of the spin torque oscillator. The main magnetic pole and the spin torque oscillator are formed between both side surfaces of the side gap. Thus, a self-alignment structure of the high frequency magnetic field assisted magnetic recording head is obtained.
1. A high frequency magnetic field assisted magnetic recording head comprising:
a main magnetic pole that generates a recording field;
a spin torque oscillator disposed on a trailing side of the main magnetic pole;
a trailing shield disposed on a surface of the spin torque oscillator on a side opposite to a surface on a main magnetic pole side;
a non-magnetic and electrically insulating side gap covering a side surface of the main magnetic pole and a surface of the spin torque oscillator; and
a side shield disposed laterally of the main magnetic pole across the side gap,
wherein A>B, where A is an angle formed by the side surface of the spin torque oscillator, and B is an angle formed by the side surface of the main magnetic pole, with respect to a plane perpendicular to a film stacked direction.
2. The high frequency magnetic field assisted magnetic recording head according to claim 1 , comprising a non-magnetic conducting layer between the side gap and the main magnetic pole.
3. The high frequency magnetic field assisted magnetic recording head according to claim 1 , wherein the trailing shield and the side shield are in contact with each other.
4. The high frequency magnetic field assisted magnetic recording head according to claim 1 , comprising a non-magnetic insulating film disposed laterally of the spin torque oscillator and between the trailing shield and the side shield for controlling the angle A.
5. A method of manufacturing a high frequency magnetic field assisted magnetic recording head, the method comprising the steps of:
forming a trench portion in a stacked film including a side shield magnetic film and an spin torque oscillator (STO) inclination control layer formed on the side shield magnetic film;
covering the trench portion with a side gap material;
filling the trench portion of the side gap material with a main magnetic pole material;
forming a side gap and a main magnetic pole by polishing until the STO inclination control layer is exposed;
forming a step recessed with respect to the side gap by etching the main magnetic pole exposed by the polishing;
forming a stacked film for a spin torque oscillator so as to cover the step;
removing the stacked film for the spin torque oscillator other than a portion of the stacked film embedded in the step; and
forming a magnetic film for a trailing shield.
6. The method of manufacturing a high frequency magnetic field assisted magnetic recording head according to claim 5 , wherein the step of forming the trench portion includes varying an etching condition during the step such that α>β, where α is an angle formed by an end surface of the STO inclination control layer that constitutes a side surface of the trench portion, and β is an angle formed by an end surface of the side shield magnetic film, with respect to a plane perpendicular to a film stacked direction.
7. The method of manufacturing a high frequency magnetic field assisted magnetic recording head according to claim 5 , further comprising:
after a side gap material layer covering the trench portion is formed, forming a non-magnetic conducting layer in a trench portion of the side gap material layer; and
filling the trench portion of the side gap material layer covered with the non-magnetic conducting layer with the main magnetic pole material.
8. The method of manufacturing a high frequency magnetic field assisted magnetic recording head according to claim 5 , further comprising removing the STO inclination control layer prior to the step of forming the magnetic film for the trailing shield.