JP3914327B2 - Thin film magnetic head and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic head used in a magnetic recording apparatus, and more particularly to a thin film magnetic head, MR head, etc. mounted on an HDD.
[0002]
[Prior art]
A thin film magnetic head used in an HDD (Hard Disk Device) is a magnetic head including an MR element that detects a magnetic field generated from a signal recorded on a medium, a magnetic pole that records a signal on the medium, and a coil. The structure of this thin film magnetic head is formed by laminating a plurality of thin films. These thin films are produced by using a film forming process by sputtering or vapor deposition, a mask process by photolithography, an etching process for removing the thin film, or the like.
[0003]
As the recording density of HDDs has increased, it has become necessary to reduce the track width of the magnetic poles of thin film magnetic heads. Here, the magnetic pole means a structure having an upper yoke and a lower yoke facing each other with a recording gap layer interposed therebetween. The track width represents the narrower one of the widths of the tip portions of either the upper yoke or the lower yoke. In order to narrow the track, a method is used in which the width of the tip of the lower magnetic pole facing the recording gap film is made narrow.
[0004]
[Problems to be solved by the invention]
In this case, a recording gap layer and an upper magnetic pole are sequentially formed on the tip. However, since the step is caused by the convex shape of the lower magnetic pole, the shape of the upper magnetic pole is distorted. Since the magnetic poles are not arranged in parallel in the track width region, the bits recorded on the medium are also distorted, which hinders improvement in recording density.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to provide a thin film magnetic head in which a surface facing a recording gap of a lower magnetic pole is flattened and an upper magnetic pole is laminated, and a method of manufacturing the same.
[0006]
[Means for Solving the Problems]
The thin film magnetic head of the present invention is a thin film magnetic head in which a recording gap film is provided between a lower magnetic pole and an upper magnetic pole, and a coil is provided around the lower magnetic pole and the upper magnetic pole. has the yoke tip has a recording gap film between the upper magnetic pole, the yoke tip is formed of NiFe layer, on both sides of the yoke tip is either Cr, Ta, and W Kano planarization film formed of a metal film of non-magnetic is formed, the planarization layer and the yoke tip is characterized by having a common plane. By using the above material, when the planarizing film and the yoke tip are simultaneously etched, variation in etching rate can be reduced, and a uniform flat surface or a common plane can be obtained.
[0009]
In the thin film magnetic head of the present invention, the lower yoke and the yoke tip are integrally formed. In the thin film magnetic head of the present invention, a reproducing head having an MR element is provided.
[0010]
Method of manufacturing a thin film magnetic head of the present invention, a recording gap layer between the lower magnetic pole and the upper magnetic pole provided with a coil around the upper pole and the lower magnetic pole, the lower magnetic pole is the lower yoke and the yoke tip a, the yoke tip has a recording gap film between the upper magnetic pole is provided with a flattening film on both sides of the yoke tip, the planarization layer and the yoke tip has a common plane In the method of manufacturing a thin film magnetic head,
The yoke tip is formed of a NiFe film, and the planarization film is formed of a non-magnetic metal film of Cr, Ta, or W,
Start the etching of both after providing the planarizing film and the yoke tip, the planarization film and the yoke tip stop etching when obtaining the plane parallel to the track width direction, of the plane A recording gap and an upper magnetic pole are formed thereon.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The thin film magnetic head of the present invention and its manufacturing process will be described below with reference to the drawings. FIG. 1 shows a method for manufacturing a thin film magnetic head of the present invention. The cross-sectional view in FIG. 1 shows each step of the manufacturing process. First, a yoke tip 2a is provided on the lower yoke 1 to form a lower magnetic pole. Further, a planarizing film 4 and a resist film 5a were sequentially laminated on the lower yoke and the yoke tip (step 1). Here, the composition of each film will be described. The lower yoke 1 is a CoTaZr film formed by sputtering. The yoke tip 2a is a NiFe film formed by plating. The planarizing film 4 is a Cr film formed by sputtering. It is desirable to use a nonmagnetic metal film for the planarizing film. Specifically, materials such as Cr, Ta, and W can be used.
[0012]
Further, (step 2) the planarizing film and the resist film laminated on the tip of the yoke are etched by ion milling, and the planarizing film remaining on both sides of the tip of the yoke is planarized by stopping the ion milling halfway. Used as the member 4a, the flattening member has a plane 4c common to the tip of the yoke. Here, ion milling is an etching method in which an inert gas or plasma gas that has been excited and ionized is accelerated and vibrated by a high-frequency electromagnetic field, and the object is scraped by colliding it.
[0013]
Subsequently, (step 3) a recording gap film 6 was formed on the common plane, and an upper magnetic pole 7 was formed on the recording gap so as to face the tip of the yoke. By forming the thin film magnetic head through the above steps, the recording gap film becomes flat at the tips of the upper magnetic pole and the lower magnetic pole. Further, by flattening the recording gap film, the side of the upper magnetic pole provided thereon facing the recording gap film can also be made flat. Therefore, even when the yoke tip is provided on the lower magnetic pole, bit distortion when writing to the recording medium using a thin film magnetic head is prevented, and the recording density can be increased.
[0014]
Next, an example of another embodiment of the present invention will be described. FIG. 2 shows a method of manufacturing the thin film magnetic head of the present invention. First (step 1), a plating film 2 is uniformly formed on the lower yoke 1, and an overhang resist 3 is formed on the plating film 2. The overhang resist refers to a resist film having a shape having a gap at both ends on the side to be bonded to the plating film.
[0015]
Further, (step 2) the overhang resist 3 and the plating film 2 are etched by ion milling to remove the plating film in the region not covered with the overhang resist, and the remaining plating film is used as the yoke tip 2a. . Subsequently, (step 3) a planarizing film 4 is formed on the overhang resist 3, the yoke tip 2a, and the lower yoke 1 by sputtering.
[0016]
Further, (step 4) the overhang resist is completely removed by etching by exposing it to a solution, and a second flattening is performed on the flattening film running on the yoke tip and both ends of the yoke tip. A film 5 is formed. Subsequently, (step 5) while etching the second flattening film by ion milling, etching is performed until the end of the flattening film riding on the tip of the yoke is also removed. As a result, the flattening film is processed into the flattening member 4a, and a plane 4c common to the yoke tip and the flattening member is obtained. Further, a recording gap film 6 and an upper magnetic pole 7 were formed on the common plane to obtain a thin film magnetic head.
[0017]
Next, an example of another embodiment of the present invention will be described. FIG. 3 shows a method of manufacturing the thin film magnetic head of the present invention. First, (step 1) a frame resist 2c was formed on the lower yoke 1 of CoTaZr, and a NiFe yoke tip 2a was formed in the resist frame by a plating method. (Step 2) After removing the frame resist by etching, an overhang resist 3 was formed on the yoke tip 2a. Next, (step 3) a flattening film 4 of Cr was formed on the overhang resist 3, the lower yoke 1, and the yoke tip 2a by sputtering. Subsequently, (Steps 4 and 5), the overhang resist 3 is removed by wet etching, and the second flattening film 5 is formed on the flattening film on the yoke tip 2a and both ends of the yoke tip. Alumina was formed. Subsequently, the second flattening film is shaved by etching by ion milling, the end of the flattening film 4 riding on the yoke tip 2a is removed, and the common plane of the yoke tip 2a and the flattening member 4a is removed. 4c was obtained. (Step 6) An alumina recording gap film 6 and a NiFe upper magnetic pole 7 were formed on the plane to obtain a thin film magnetic head.
[0018]
FIG. 4 is a cross-sectional view of the thin film magnetic head of the present invention.
The reproducing head 12 in FIG. 4 has a structure in which an MR element 8 and an electrode film 9 are provided between the lower shield 11 and the lower magnetic pole 1 via a reproducing gap film 10. Two electrode films 9 are bonded to both ends of the MR element, and supply current to the MR element. The structure of the thin film magnetic head described with reference to FIGS. 1, 2, and 3 was used for the recording head above the lower yoke. Although not shown in the figure, the electrode film 9 is a two-layer film of electrode film / permanent magnet film, and a current and a bias magnetic field are applied to the MR element.
[0019]
【The invention's effect】
According to the present invention, the recording density of the recording medium can be improved by flatly forming the side of the upper magnetic pole facing the recording gap film.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a method for manufacturing a thin film magnetic head of the present invention.
FIG. 2 is a cross-sectional view illustrating a method for manufacturing a thin film magnetic head of the present invention.
FIG. 3 is a cross-sectional view illustrating a method for manufacturing a thin film magnetic head of the present invention.
FIG. 4 is a cross-sectional view of a thin film magnetic head of the present invention.
[Explanation of symbols]
1 Lower yoke, 2 plating film, 2a yoke tip, 2c frame resist, 3 overhang resist, 4 planarizing film, 4a planarizing member, 4c common plane, 5 second planarizing film, 5a resist film, 6 Recording gap film, 7 Upper magnetic pole, 8 MR element, 9 Electrode film, 10 Reproduction gap film, 11 Lower shield, 12 Reproduction head

Claims (4)

The recording gap layer between the lower magnetic pole and the upper magnetic pole provided, a thin-film magnetic head having a coil around the lower magnetic pole and the upper pole, lower pole has a lower yoke and the yoke tip, the yoke tip has a recording gap film between the upper magnetic pole, the yoke tip is formed of NiFe layer, on both sides of the yoke tip, Cr, Ta, either in the non-magnetic metal film W formed a planarization film is formed, the planarization layer and the yoke tip thin film magnetic head and having a common plane. The thin-film magnetic head according to claim 1, wherein the yoke tip and the lower yoke, characterized in that it is formed integrally. 3. A thin film magnetic head comprising a reproducing head having an MR element in the thin film magnetic head according to claim 1. The recording gap layer between the lower magnetic pole and the upper magnetic pole provided with a coil around the upper pole and the lower magnetic pole, the lower magnetic pole has a lower yoke and the yoke tip, the yoke tip the upper magnetic the recording has a gap film, the yoke tip both sides provided with a flattening film, before Symbol method of manufacturing a thin film magnetic head wherein the planarization layer and the yoke tip having a common plane between,
The yoke tip is formed of a NiFe film, and the planarization film is formed of a non-magnetic metal film of Cr, Ta, or W,
Wherein the yoke tip to start etching both after providing a planarizing film, after the planarizing film and the yoke tip has stopped etching when obtaining the plane parallel to the track width direction, wherein A method of manufacturing a thin film magnetic head, wherein a recording gap and an upper magnetic pole are formed on a plane.

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