JP3164050B2 - Manufacturing method of magnetoresistive composite head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a magneto-resistive composite head including a reproducing head utilizing a magneto-resistive effect and an inductive recording head.

[0002]

2. Description of the Related Art A magnetoresistive head (hereinafter referred to as a composite head) includes a magnetoresistive head and an inductive head (inductive head;
ID head). In a practical composite head, the MR head is used as a read head, and has two opposing magnetic shield films S1 and S2, and S1 and S2.
And a magnetoresistive effect element interposed therebetween and separated by a magnetic separation layer forming an insulator therefrom. Also, I
The D head is used as a recording head, and one of the two magnetic shield films S1 and S2 of the MR head is used as one magnetic pole film P1.
Has a coil sandwiched between insulators and another magnetic pole P2 on the surface opposite to the MR effect element. P1 and P2 are stacked in parallel with each other, and perform recording by a magnetic field generated in a magnetic gap 15 provided between P1 and P2.

As the recording density increases, the track width W at the end of the upper magnetic pole P2 defining the recording track width on the surface (air floating surface, hereinafter referred to as ABS surface) facing the recording magnetic medium must be narrower. Is required. However, in the process of forming the upper magnetic pole P2 after forming the lower magnetic pole P1 and then forming the coil covered with the insulating layer,
A photoresist frame (hereinafter referred to as a resist frame) for determining the outer shape of the upper magnetic pole P2 must be formed on a coil covered with an insulating layer whose center portion is thicker and thinner toward its ends, Further, since the end of the upper magnetic pole P2 that defines the recording track width W is located near the end of the coil insulating layer, it is difficult to narrow the end of the upper magnetic pole P2, and its limit is about 2 μm. there were.

In the manufacturing method described in JP-A-7-225917, the upper magnetic pole P2
Is formed before the formation of the coil covered with the insulating layer, and thereafter, the coil portion and other upper magnetic pole portions are formed. Thus, the upper magnetic pole P2
1 μm by forming the tip of
An upper magnetic pole P2 having a narrow end is formed.

[0005]

The present inventor actually manufactured an ID head by the method described in the above publication. However, the described method is not only complicated in steps but also involves the following problems.

First, when forming the leading end of the upper magnetic pole P2 to be formed in advance by using a frame plating method in consideration of the manufacturing cost, the leading end of the upper magnetic pole P2 becomes a throat height (the end of the insulating layer of the coil). Length from the surface to the ABS)
Is defined at the zero position, the shape of the resist frame is a U-shaped blind alley.

Therefore, when the magnetic pole is formed by ordinary paddle plating, it is difficult for the plating solution to sufficiently flow in this dead end, and as a result, the composition of the formed plating film changes,
The magnetic properties at the tip of the upper magnetic pole P2, which requires the best magnetic properties, are degraded or varied, and the manufacturing yield is reduced.

Further, in the upper magnetic pole P2, the variation in the throat height becomes large. The throat height is I
Strict control is necessary because it greatly affects the recording performance such as the overwrite characteristics of the D head. However, in the present head, since it is difficult to control the length, the production yield further decreases.

An object of the present invention is to eliminate the necessity of separately forming only the tip of the upper magnetic pole P2 of the ID head as a pre-process before forming the coil. It is an object of the present invention to provide a method for manufacturing a magnetoresistive composite head which is high in performance and can realize a narrow track width.

[0010]

In order to achieve the above object, a method of manufacturing a magnetoresistive head according to the present invention comprises:
A pair of magnetic shield films sequentially laminated on the slider,
A read head having a magnetoresistive (hereinafter referred to as MR) effect element disposed between the pair of magnetic shield films; and the first magnetic shield as a first write magnetic pole. A method of manufacturing a magnetoresistive composite head, comprising: a recording head having a second recording magnetic pole opposed to a recording magnetic gap, wherein a step of forming a resist frame; The method further includes a step of forming a recording magnetic pole by a plating method and a step of trimming the second recording magnetic pole so that a leading end width thereof becomes a desired width before removing the resist frame. According to the present invention, the portion under the resist frame can be protected by performing the trimming while leaving the resist frame. Here, it is preferable that the trimming process uses a focus ion beam (FIB) method. In this case, high dimensional accuracy is obtained. Further, in the trimming step, it is preferable that a part of the resist frame is removed but not divided. In this case, it is possible to prevent the magnetic pole from being eroded by the etchant in a subsequent step. It is preferable that an alignment mark for a trimming process is formed on the resist frame. In this case, positioning in the trimming step is facilitated.

[0011]

The present invention will be described in more detail with reference to the drawings. FIG. 1 is a cross-sectional view of a composite head manufactured by a manufacturing method according to an embodiment of the present invention as viewed from the ABS. A lower shield 11 is formed on a wafer 21, on which an MR element 12 having a central region 12A and an end region 12B is arranged.
Third, the upper magnetic pole 14 is formed. Upper shield 1
3 is provided with a convex portion 16, and a gap layer 15 made of an alumina layer is provided between the convex portion 16 and the upper magnetic pole 14.
Is arranged.

FIG. 2 shows an Al ₂ O ₃ -T constituting a slider.
1 shows a state in which the elements shown in FIG. 1 are formed on a wafer 21 made of an iO composite ceramic so as to be aligned vertically and horizontally. After each element is cut out from this state, the ABS surface is polished.

FIGS. 3 (a) to 3 (d) are plan views of the respective manufacturing steps of the respective elements shown in FIG. 2 and sequentially show the main manufacturing steps in the method of manufacturing the magnetoresistive composite head. Is shown.

First, a 1 μm-thick Co—Ta—Zr film is formed on the wafer by sputtering, and the lower shield S 1
Patterned as (11). After that, an alumina film having a thickness of 80 nm is formed by sputtering as an insulating film to be one of the reproducing magnetic gaps. Then, the MR film is used as the central region 12A (FIG. 1), and a laminated film including the electrode film and the magnetic bias film is formed. The MR element 12 having the end region 12B is formed. The laminated film constituting the central region of the MR element is made of Ni having a thickness of 30 nm.
-Mn film, 3 nm thick Co-Fe film, 2.5 nm thick
And a spin valve film made of a 6-nm-thick Ni—Fe film. The magnetic bias film is also formed of a laminated film, and has a 10 nm-thick Cr underlayer, a thickness of 4 mm.
0 nm Co-Cr-Pt permanent magnet film, 5 nm thick T
a Adhesion film, composed of an Au film having a thickness of 100 nm.

Next, after a 60 nm-thick alumina film serving as the other reproducing magnetic gap is formed by sputtering, a 2 μm-thick Ni—Fe film pattern constituting the upper shield / electrode 13 is formed by frame plating. Form. next,
A 0.25 μm-thick alumina film 15 serving as a recording magnetic gap is formed by sputtering, and a magnetic field generating coil 25 of a recording head covered with an insulating resist is formed thereon.
As a result, the structure shown in FIG.

Further, a resist frame 26 for patterning the upper magnetic pole P2 (14) of the recording head is formed by pattern transfer using a mask, and a Ni-Fe film as the upper magnetic pole 14 is formed inside the resist frame 26. Is formed by plating. Thus, the structure shown in FIG. 3B is obtained.

Next, a trimming process 28 is performed using the FIB method while the resist frame 26 is left. The track width W at the tip of the upper magnetic pole P2 is determined by this trimming. As a result, the structure shown in FIG. 3C is obtained. By leaving the resist frame 26, a portion under the resist frame that does not need to be cut by the FIB can be protected. The layers to be cut off during the trimming are the upper magnetic pole 14, the resist frame 26, the alumina film 15 as a gap layer, and the projections of the upper shield 13 from the upper layer.

Next, in order to finally leave the magnetic pole pattern in the frame, the resist frame is covered with a resist cover, and an unnecessary portion of the plated Ni-Fe film 29 other than the magnetic pole on the outer peripheral portion of the resist frame 26 is subjected to chemical etching. Remove. Thus, the structure shown in FIG. 3D is obtained. At this time, the resist frame 26 is partially cut by the FIB method as shown in FIG. 3C, but the resist frame is not divided. This can prevent the etching solution from eroding the upper magnetic pole P2 in the resist frame. Next, the resist frame 26 is removed, the device is covered with a 30 μm-thick alumina film, and an electrode pad is formed to complete the device on the wafer. 3 (d) shows the polished surface of the ABS surface described in FIG.

FIG. 4 shows an example of a resist frame used in the above manufacturing method. After the resist frame 26 is formed by pattern transfer using a mask, the upper magnetic pole P2 is formed by plating. Then, FIB
The process of trimming the tip width of the upper magnetic pole P2 for determining the track width W is performed with the resist frame left. This is by leaving the resist frame
This is to protect the lower part of the frame that does not require trimming by the FIB method. The resist frame is partially removed by the FIB process 28 as shown in FIG. In this case, as described above, the resist frame is not cut. This removes unnecessary plating film 29 on the periphery of the resist frame by chemical etching,
This is to prevent the etchant from eroding the magnetic poles in the resist frame in the step of finally leaving the pattern of the upper magnetic pole P2 in the resist frame. An alignment mark 32 shown in FIG. 4 is provided on the resist frame to facilitate the positioning image processing in the trimming step by the FIB.

According to the manufacturing method of the present invention, the width W of the upper magnetic pole 14, which determines the track width of the recording head, is suitable for high-density recording of 2 μm or less. Further, by adjusting the FIB process, it is possible to form the convex portion 16 corresponding to the upper magnetic pole 14 on the upper shield 13, thereby realizing the recording in which the recording bleeding in the lateral direction of the track width is suppressed.

By adjusting the FIB process, it is possible to form a structure having no projection 16 on the upper shield. Also,
As the lower shield material 11, besides the Co-Ta-Zr film, a film generally called a soft magnetic film, that is, Ni-Fe
Similar results can be obtained with a film, a Co-based amorphous film, an Fe-based or Co-based microcrystalline film, or a sendust film.

The same result can be obtained if the MR film 12 is a film generally called a spin valve in addition to the above-mentioned spin valve film. Also, Ni-Fe
Similar results are obtained when a general MR film using an anisotropic magnetoresistance effect such as a film is used, and when a MR film using a ferromagnetic tunnel junction type MR effect is used.

Similar results can be obtained by using a Co-based amorphous film or the like as the upper shield film 13 in addition to the Ni-Fe film. Further, as the upper magnetic pole film, in addition to the Ni—Fe film, a plating film generally called a soft magnetic film, ie, Ni
A similar result can be obtained with an Fe—Co film or the like.

Although the present invention has been described based on the preferred embodiment, the method of manufacturing the magnetic effect type composite head of the present invention is not limited to the configuration of the above-described embodiment, but is limited to the above embodiment. A method of manufacturing a magnetic effect type composite head in which various modifications and changes are made from the configuration of the embodiment is also included in the scope of the present invention.

[0025]

According to the manufacturing method of the present invention, the width of the upper magnetic pole for determining the recording track width can be accurately set to 2 μm or less, and a composite head suitable for high-density recording can be manufactured with high yield.

[Brief description of the drawings]

FIG. 1 is an end view of a magnetoresistive composite head manufactured according to the present invention as viewed from a surface facing a magnetic medium.

FIG. 2 is a plan view showing one stage of the manufacturing process of the present invention.

3A and 3B are diagrams showing a manufacturing process of the present invention, in which FIG. 3A shows up to a coil laminating process, FIG. 3B shows a resist frame transferring process and a Ni—Fe film plating process, and FIG.
(D) shows a trimming process step and a step after the step of removing the plating film of the Ni—Fe film and the step of removing the resist frame.

FIG. 4 is a diagram showing an example of a resist frame used in the manufacturing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Lower shield 12 MR element 13 Upper shield 14 Upper magnetic pole 15 Gap layer 16 Upper shield convex part 21 Wafer 25 Recording head coil / insulator formation 26 Upper magnetic pole patterning photoresist frame formation 28 FIB processing hole 29 Unnecessary partial plating film 31 Resist Frame 32 Notch of resist frame H Throat height W Track width

Claims (4)

(57) [Claims] A reproducing head having a pair of magnetic shield films sequentially stacked on a slider, and a magnetoresistive (hereinafter referred to as MR) effect element disposed between the pair of magnetic shield films; A method of manufacturing a magneto-resistive composite head comprising: a first magnetic shield as a first recording magnetic pole; and a recording head having a second recording magnetic pole opposed to the first recording magnetic pole across a recording magnetic gap. Forming a resist frame, forming a second recording magnetic pole inside the resist frame by plating, and removing the resist frame before removing the resist frame.
Trimming so that the leading end width of the recording magnetic pole becomes a desired width. 2. The method according to claim 1, wherein the trimming step uses a focus ion beam (FIB) method. 3. The method according to claim 1, wherein in the trimming step, a part of the resist frame is removed but not divided. 4. The method according to claim 1, wherein an alignment mark for a trimming step is formed on the resist frame.