Magnetic head, manufacturing method thereof, head gimbal assembly using the magnetic head, and hard disk device using the magnetic head

Abstract

The present invention aims to provide a magnetic head having an air bearing surface (ABS) composed of a worked surface being flat and smooth and having a reduced step produced between a rail portion on the ABS and an element portion. For achieving the object, the present invention makes a first predetermined depth deeper than a second predetermined depth in a manufacturing method of a magnetic head, which method executes the following steps. In the method, an electromagnetic transducing element is formed on a board, and then only the specific plane, which is opposed to a magnetic recording medium, of the board is removed up to a first predetermined depth. An insulating film, which is composed of the same material as that of an insulating layer used at the time of the formation of the element, is formed on the surface of the board after the removal and the surface of the element portion, and then the insulating film is polished by a chemical mechanical polishing method till the element is exposed. After that, a recessed portion having a second predetermined depth is formed on the insulating film.

What is claimed is:  
     
         1 . A magnetic head including at least either of a recording element and a reproducing element, each being formed by lamination of a plurality of insulating layers, a conductive layer and a magnetic layer on an end face of a substrate and by work of each of the layers to a predetermined shape, said magnetic head comprising: 
 a recessed portion on a specific plane opposed to a magnetic recording medium to be an object which said elements record information on or reproduce information from,    wherein a part of said specific plane except at least the conductive layer and the magnetic layer in the portion of said elements, a bottom face of said recessed portion and a side wall portion of said recessed portion are made from a same material.    
     
     
         2 . A magnetic head according to  claim 1 , wherein the same material is alumina.  
     
     
         3 . A magnetic head according to  claim 1 , wherein the material of the bottom face and the side wall of said recessed portion differs from a material of said substrate.  
     
     
         4 . A head gimbal assembly using a magnetic head including at least either of a recording element and a reproducing element, each being formed by lamination of a plurality of insulating layers, a conductive layer and a magnetic layer on an end face of a substrate and by work of each of the layers to a predetermined shape, said magnetic head comprising: 
 a recessed portion on a specific plane opposed to a magnetic recording medium to be an object which said elements record information on or reproduce information from,    wherein a part of said specific plane except at least the conductive layer and the magnetic layer in the portion of said elements, a bottom face of said recessed portion and a side wall portion of said recessed portion are made from a same material.    
     
     
         5 . A hard disk device using a magnetic head including at least either of a recording element and a reproducing element, each being formed by lamination of a plurality of insulating layers, a conductive layer and a magnetic layer on an end face of a substrate and by work of each of the layers to a predetermined shape, said magnetic head comprising: 
 a recessed portion on a specific plane opposed to a magnetic recording medium to be an object which said elements record information on or reproduce information from,    wherein a part of said specific plane except at least the conductive layer and the magnetic layer in the portion of said elements, a bottom face of said recessed portion and a side wall portion of said recessed portion are made from a same material.    
     
     
         6 . A manufacturing method of a magnetic head comprising: 
 a step of forming an element portion including at least either of a recording element and a reproducing element by laminating a plurality of insulating layers, a conductive layer and a magnetic layer on an end face of a substrate and by working each of the layers to a predetermined shape;    a first polishing step of polishing a specific plane of said substrate, said specific plane being opposed to a magnetic recording medium, which said elements record information on or reproduce information from, and a specific plane of said element portion, said specific plane being opposed to said magnetic recording medium in said element portion;    a removal step of removing only said specific plane of said substrate up to a first predetermined depth;    a film forming step of forming an insulating film on a surface of said specific plane of said substrate after removing said specific plane to the predetermined depth of said substrate and on a surface of said specific plane of said element portion;    a second polishing step of polishing said insulating film till at least either of the conductive layer and the magnetic layer in said element portion is exposed; and    a recessed portion forming step of forming a recessed portion having a predetermined shape and a second predetermined depth on said insulating film after said second polishing step;    wherein said first predetermined depth is deeper than said second predetermined depth.    
     
     
         7 . A manufacturing method of a magnetic head according to  claim 6 , wherein said insulating film formed on the surface of said specific plane of said substrate and the surface of said specific plane of said element portion is made from a same material as that of any one of the plurality of insulating layers forming said element portion.  
     
     
         8 . A manufacturing method of a magnetic head according to  claim 6 , wherein said second polishing step includes a chemical mechanical polishing method using an abrasive liquid adjusted to be pH 5-7.  
     
     
         9 . A manufacturing method of a magnetic head comprising: 
 a step of forming an element portion including at least either of a recording element and a reproducing element by laminating a plurality of insulating layers, a conductive layer and a magnetic layer on an end face of a substrate and by working each of the layers to a predetermined shape;    a first polishing step of polishing a specific plane of said substrate, said specific plane being opposed to a magnetic recording medium, which said elements record information on or reproduce information from, and a specific plane of said element portion, said specific plane being opposed to said magnetic recording medium in said element portion;    a removal step of removing only said specific plane of said substrate up to a predetermined depth;    a film forming step of forming an insulating film on a surface of said specific plane of said substrate after removing said specific plane to the predetermined depth of said substrate and a surface of said specific plane of said element portion; and    a second polishing step including a chemical mechanical polishing method for polishing said insulating film till at least either of the conductive layer and the magnetic layer in said element portion is exposed.    
     
     
         10 . A manufacturing method of a magnetic head according to  claim 9 , wherein said insulating film to be formed on the surface of said specific plane of said substrate and the surface of said specific plane of said element portion is made from a same material as that of any one of the plurality of insulating layers forming said element portion.  
     
     
         11 . A manufacturing method of a magnetic head according to  claim 9 , wherein said second polishing step further includes a preliminary polishing step using a polishing plate composed of an abrasive paste and a soft metal and said preliminary polishing step is performed at a pre-step of said chemical mechanical polishing method.  
     
     
         12 . A manufacturing method of a magnetic head according to any one of  claims 9  to  11 , wherein said chemical mechanical polishing method uses an abrasive liquid adjusted to be pH 5-7 and a chelating reagent as an additive.