Magnetic head, magnetic head assembly, magnetic recording and reproducing apparatus, and method for manufacturing magnetic head

Abstract

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.

What is claimed is: 
     
         1 . A magnetic head comprising a reproducing unit configured to detect a medium magnetic field recorded in a magnetic recording medium,
 the reproducing unit including:
 a first magnetic shield; 
 a second magnetic shield; 
 a stacked body provided between the first magnetic shield and the second magnetic shield, 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, the stacked body having a side wall, the side wall intersecting a plane perpendicular to a stacking direction from the first magnetic shield toward the second magnetic shield; and 
 a side wall film covering at least a part of the 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. 
   
     
     
         2 . The head according to  claim 1 , wherein the side wall film includes at least one of oxygen, nitrogen, and carbon. 
     
     
         3 . The head according to  claim 1 , wherein the side wall film includes a compound including at least one of oxygen, nitrogen, and carbon. 
     
     
         4 . The head according to  claim 1 , wherein the side wall film includes an oxide including at least one of oxygen, nitrogen, and carbon. 
     
     
         5 . The head according to  claim 1 , wherein the side wall film is electrically non-conductive. 
     
     
         6 . The head 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 head 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 head according to  claim 1 , wherein
 the first magnetic layer is disposed between the first magnetic shield and the intermediate layer.   
     
     
         9 . The head according to  claim 1 , wherein
 the intermediate layer is nonmagnetic.   
     
     
         10 . The head according to  claim 1 , wherein a direction of a magnetization of the first magnetic layer and a direction of a magnetization of the second magnetic layer change in accordance with the medium magnetic field. 
     
     
         11 . The head according to  claim 1 , wherein
 the first magnetic layer has a first magnetization, the first magnetization has a first component in a track width direction of the magnetic recording medium,   the second magnetic layer has a second magnetization, the second magnetization has a second component in the track width direction of the magnetic recording medium, and   a direction of the first component is opposite to a direction of the second component.   
     
     
         12 . The head according to  claim 1 , wherein
 a current is passed in the stacked body through the first magnetic shield and the second magnetic shield.   
     
     
         13 . The head according to  claim 1 , wherein
 the second magnetic shield includes
 an upper portion covering the stacked body. 
 an opposed portion opposed to the side wall of the stacked body via the side wall film. 
   
     
     
         14 . The head according to  claim 13 , wherein
 the second magnetic shield further includes a Ru film provided between the upper portion and the opposed portion.   
     
     
         15 . The head according to  claim 14 , wherein
 the Ru film overlays the intermediate layer when projected onto a plane parallel to a direction from the first magnetic shield toward the second magnetic shield.   
     
     
         16 . The head according to  claim 1 , wherein
 the first magnetic shield has a protrusion provided in a portion opposed to the stacked body.   
     
     
         17 . A magnetic head assembly comprising:
 a magnetic head including a reproducing unit configured to detect a medium magnetic field recorded in a magnetic recording medium, the reproducing unit including:
 a first magnetic shield; 
 a second magnetic shield; 
 a stacked body provided between the first magnetic shield and the second magnetic shield, 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, the stacked body having a side wall, the side wall intersecting a plane perpendicular to a stacking direction from the first magnetic shield toward second magnetic shield; and 
 a side wall film covering at least a part of the 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; 
   a suspension, the magnetic head being mounted at one end of the suspension; and   an actuator arm connected to another end of the suspension.   
     
     
         18 . A magnetic recording and reproducing apparatus comprising:
 a magnetic head assembly; and   a magnetic recording medium,   the magnetic head assembly including:
 a magnetic head including a reproducing unit configured to detect a medium magnetic field recorded in the magnetic recording medium, the reproducing unit including:
 a first magnetic shield; 
 a second magnetic shield; 
 a stacked body provided between the first magnetic shield and the second magnetic shield, 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, the stacked body having a side wall, the side wall intersecting a plane perpendicular to a stacking direction from the first magnetic shield toward second magnetic shield; and 
 a side wall film covering at least a part of the 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; 
 
 a suspension, the magnetic head being mounted at one end of the suspension; and 
 an actuator arm connected to another end of the suspension; and 
   the magnetic recording medium from which information is reproduced using the magnetic head mounted on the magnetic head assembly.   
     
     
         19 . 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 configured to detect a medium magnetic field recorded in a magnetic recording medium.   
     
     
         20 . A method for manufacturing a magnetic head, the method comprising:
 forming a stacked film on a first magnetic shield, 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, while forming a 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 by causing a material included in the stacked film to adhere to a side wall of the stacked body; and   forming a second magnetic shield on the stacked body to form a reproducing unit configured to detect a medium magnetic field recorded in a magnetic recording medium.