JPH09231524A - Method for manufacturing MR head for hard disk drive - Google Patents

Abstract

(57) Abstract: The direction of an applied magnetic field to a head element is 180 without changing the direction of an applied magnetic field in a manufacturing facility or the mounting direction of a ceramic substrate to the manufacturing facility.
° Different head elements for A side and B side can be easily manufactured without confusion, and the direction of the applied magnetic field can be easily determined at any time during the wafer process. A method of manufacturing an MR head for a hard disk device, in which a magnetic field is applied during formation of an MR film and heat treatment in a wafer process. The direction of the applied magnetic field in the wafer process and the orientation of the ceramic substrate relative to it are kept constant, and the orientation of the pattern of the head element portion arranged on the ceramic substrate is 1 for A side and B side of the magnetic recording medium.
They are formed differently by 80 °. In that case, the direction of the pattern of the head element portion is 180 on one ceramic substrate.
° Forming area 60a for A side and forming area 6 for B side are different
It is also possible to mix 0b.

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 an MR type thin film magnetic head used in a hard disk device. More specifically, the present invention, in a wafer process in which a large number of head element portions are regularly arranged and formed on a ceramic substrate, the direction of the applied magnetic field and the orientation of the ceramic substrate relative thereto are kept constant for all the ceramic substrates, The present invention relates to a method of manufacturing an MR head in which patterns of head element portions arranged on a ceramic substrate are formed by differentiating 180 ° C. between the A side and the B side.

[0002]

2. Description of the Related Art An MR head is one type of thin film magnetic head for a hard disk drive. This utilizes the MR effect (magnetoresistive effect) in which the electric resistance changes due to a magnetic field or magnetization, for reading (reproducing) information, and a read unit having an MR film on a ceramic substrate and a magnetic field generating unit. The writing unit having the coil is laminated in that order. The read section is M between the lower shield and the upper shield.
The R film is located, and the writing part is configured to sandwich the gap film between the lower magnetic pole and the upper magnetic pole, and generate a magnetic field for writing by energizing the coil. The MR head is classified into a separate type in which an upper shield of the read section and a lower magnetic pole of the write section are separately provided via a separation layer, and a shared type in which the upper shield of the read section and the lower magnetic pole of the write section are used together. is there. Since the shared type has a small number of layers to be formed and the process is simplified accordingly, it is currently the mainstream of MR heads.

An example of the shared MR head is shown in FIG.
(A) is a perspective view which shows the principal part typically, (b) is the figure seen from the air bearing surface, (c) has shown the vertical cross section perpendicular to it. As described above, the reading section 12 is provided on the ceramic substrate 10 and the writing section 14 is provided thereon. The reading section 12 has an MR film 16, and lead wires 18 made of an antiferromagnetic exchange coupling film are provided on the upper surfaces of both ends of the MR film 16, and these lead wires serve as a lower shield 20 and an upper shield / lower magnetic pole 22. It has a structure in which the gap layer 24 is interposed therebetween. There is also a hard bias type in which lead lines made of a film of a ferromagnetic material (magnet) are provided at both ends of the MR film 16, which is currently the mainstream type. The write unit 14 has the upper shield / lower magnetic pole 22, the write gap layer 26, and the upper magnetic pole 28, and insulates between the upper shield / lower magnetic pole 22 and the upper magnetic pole 28 at a position recessed from the air bearing surface. This is a configuration in which a single layer or a plurality of layers of magnetic field generating coils 32 sandwiched between layers are arranged.

As shown in FIG. 2, in one wafer 40, there is a rule of about 200 to 300 processing blocks 44 in which ten to several tens of such head element portions 42 are arranged in a horizontal row. Formed. Then, after the wafer process is finished, it is cut into each processing block, subjected to the gap depth processing, respectively, and then cut and separated into each head element portion to manufacture. The ceramic substrate used here is typically in the shape of a disk, and has a shape in which a part thereof is linearly cut to determine its direction. In the conventional technique, all the manufactured wafers are formed so that the head element portions are oriented in the same direction with respect to the ceramic substrate.

By the way, in the manufacturing process of such an MR head, magnetic anisotropy is imparted when the MR film is formed,
Further, in order not to lose the magnetic anisotropy during the heat treatment, it is necessary to perform the film formation and the heat treatment while applying a magnetic field in a fixed direction. In reality, for example, a magnetic field in a constant direction is always applied in the film forming process of the read section, the film forming process of the shield and the magnetic pole, and the heat treatment process thereof. Specifically, not only the MR film but also the S
In the case of AL bias type, antiferromagnetic exchange coupling film,
In the case of the hard bias type, a magnetic field is applied in a fixed direction even in the step of forming a hard film that creates a bias magnetic field, so that the bias magnetic field is applied to the MR film in a fixed direction. Further, not only in the reading section but also in the step of forming the shield and the magnetic pole, a magnetic field in a fixed direction is applied in order to give them magnetic anisotropy. Furthermore, although heat treatment is performed on these magnetic films after film formation, generally, when heat treatment is performed, the magnetic anisotropy decreases and becomes isotropic. Therefore, heat treatment is performed in a magnetic field so that the magnetic anisotropy does not decrease as much as possible. To do. The direction of the magnetic field applied in these steps is either the longitudinal direction of the MR film, that is, the direction indicated by the arrow Ha in FIG. 1A or the direction indicated by the opposite arrow Hb.

[0006]

As shown in FIG. 3A, in a hard disk device, a disk-shaped magnetic recording medium 48 is attached to a spindle 46 that rotates at a high speed by a motor (not shown) or the like. In many cases, the MR heads 50 are arranged so as to face both sides of the magnetic recording medium 48. In that case, one is referred to as the A side and the other is referred to as the B side to distinguish them (sometimes referred to as up and the other as down). In this type of hard disk device, as shown in FIG. 3B, the magnetization direction (represented by an arrow M) of the read section 12 of the MR head with respect to the magnetic recording medium 48 is the same for the A side and the B side. It is empirically known that the characteristics do not improve unless it is set. In order to set the MR head on the A side and the MR head on the B side in the same direction with respect to the rotation direction of the magnetic recording medium, the magnetization directions of the read section 12 of the MR head are set for the A side and the B side. It is necessary to reverse with and.

For that purpose, the direction of the magnetic field applied in the manufacturing equipment in the wafer process may be changed between for the A surface and for the B surface, but generally it is not easy to reverse the magnetic field direction of the equipment in the manufacturing line. Absent. Therefore, in the conventional technology, the mounting direction of the ceramic substrate with respect to the manufacturing equipment is changed by 180 °. However, in this method, it is necessary to change the jig and the mounting direction of the ceramic substrate according to the A side and the B side, and it is necessary to check the pattern arrangement of the head element portion on the ceramic substrate. Since the magnetization direction cannot be determined simply by doing so, it leads to confusion at the manufacturing site and complication of work.

The object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to apply the magnetic field applied to the head element section without changing the direction of the applied magnetic field in the manufacturing equipment or the mounting direction of the ceramic substrate to the manufacturing equipment. Provided is a method of manufacturing an MR head which can easily manufacture two types of head element parts for A surface and B surface having different directions of 180 ° without confusion and can easily determine the direction of an applied magnetic field at any time during a wafer process. It is to be.

[0009]

According to the present invention, a gap film is sandwiched between a lower magnetic pole and an upper magnetic pole, and a magnetic field is internally generated on a read portion having an MR film located between a lower shield and an upper shield. In a wafer process of an MR head in which a large number of head element parts having a structure in which writing parts having a coil for use for magnetic recording are laminated are regularly formed on a ceramic substrate, when a magnetic field is applied during the formation of the MR film and the heat treatment. , The direction of the applied magnetic field and the orientation of the ceramic substrate with respect to the direction of the applied magnetic field are kept constant for all the ceramic substrates, and the orientation of the pattern of the head element portion arranged on the ceramic substrate is for the A side of the magnetic recording medium and for the B direction.
This is a method of forming 180 ° different for the surface.

In this case, on one ceramic substrate,
It is preferable that the A-side forming region and the B-side forming region in which the pattern orientation of the head element portion differs by 180 ° are mixed and manufactured. As another method, a head element part for the A side is formed on one ceramic substrate and a head element part for the B side, which is different from the head element by 180 °, is formed on the one ceramic substrate. There is also a method of flowing the formed material to the production line at an appropriate ratio.

In the wafer process, when a magnetic field is applied not only in the MR film but also in forming all other magnetic films (shields and magnetic poles) and heat treatment, the direction of the applied magnetic field and The orientation of the ceramic substrate with respect to the direction of the applied magnetic field is kept constant for all ceramic substrates. The method of the present invention is a separation type M
It can be applied to both the R head and the shared MR head.

[0012]

The basic steps of manufacturing an MR head may be similar to the prior art. Set the orientation of the pattern of the head element part arranged on the ceramic substrate to A
If the surface and B surfaces are formed differently by 180 °, the direction of the applied magnetic field in the wafer process and the orientation of the ceramics substrate with respect to the direction of the applied magnetic field are set to be the same for all the ceramics substrates. It is possible to obtain two types of MR heads in which the magnetization direction of the read section differs by 180 °. Since the difference in the magnetization direction appears as the orientation of the pattern of the head element portion on the ceramic substrate, it can be easily visually determined at any time during the wafer process or even after all the wafer processes are completed.

[0013]

EXAMPLE An MR head manufactured by the method of the present invention may be a shared type or a separated type. Further, the method of the present invention can be applied to a SAL bias type using an antiferromagnetic exchange coupling film and a hard bias type using a hard film for generating a bias magnetic field as a type for applying a bias magnetic field in a fixed direction to the MR film. . The basic configuration of the head element portion and the manufacturing process, particularly the wafer process, may be the same as those in the above-described conventional technique, and detailed description thereof is omitted because it is redundant.

The head element portion is manufactured by sequentially forming a film having a predetermined shape and a predetermined thickness on a ceramic substrate using a photolithography technique. Taking the configuration of the head element portion of FIG. 1 as an example, for example, M
The R film is a NiFe film, the lead line made of an antiferromagnetic exchange coupling film is a FeMn film, the hard bias type lead line is CoCrPt, CoPt, or the like, and the shield or magnetic pole is a NiFe film. To form each of these films into a predetermined shape, an exposure mask having a required shape is used. Therefore,
The exposure mask determines the orientation of each head element portion to be formed.

In the present invention, at least when the MR film is formed,
And, when it is subjected to heat treatment, a magnetic field having a constant direction is always applied to impart magnetic anisotropy, and the magnetic anisotropy is not lost. Actually, the magnetic field is applied in all of the film forming process of the read-out portion (MR film, exchange coupling film or hard film for creating a bias magnetic field), shield and magnetic pole film forming process, and their heat treatment processes. These are for imparting magnetic anisotropy to each magnetic film and for preventing the magnetic anisotropy from decreasing. The magnetic fields are all applied in the same direction by the magnetic field generators incorporated in the manufacturing line.

FIGS. 4A to 4C show an example of a wafer according to the method of the present invention. In these examples, the orientation of the pattern of the head element portion is 180 in one wafer 40.
° Forming area 60a for A side and forming area 6 for B side are different
This is the case where 0b is mixed. That is, in the wafer process, the direction of the applied magnetic field and the orientation of the ceramics substrate with respect to the direction of the applied magnetic field are kept constant for all the ceramics substrates, and a wafer having a head element portion arrangement as shown in FIG. (A) is a ceramic substrate divided into upper and lower parts, one of which is a forming area 60a for the A surface, the other is a head element portion 42a for the A surface, and the other is a forming area 60b for the B surface, which is a head element for the B surface. The portions 62b are formed in an array. Further, as shown in (b), a left and right division method may be used, or as shown in (c), any other division method may be used. In any case, one side is used as the formation area 60a for the A side, and the head element portion 42a for the A side is used, and the other side is used as the B side.
The head element portion 62 for the B side as the formation region 60b for the side
b are arrayed.

In this way, a magnetic field in a fixed direction is generated in the manufacturing line and the magnetic field in the same direction is applied to each wafer. However, in one wafer, the head element portions 42a and 42B for the A surface are formed. The surface head element portion 42b is formed, and the directions of the magnetic fields applied to the magnetic films of the head element portions can be different by 180 °. Therefore, by incorporating them so as to face one surface of the magnetic recording medium and the surface opposite thereto, a hard disk device having excellent characteristics can be obtained.

As another method, as shown in FIG.
Wafer 40a for A side forming only head element section 42a for A side, and wafer 40b for B side forming only head element section 42b for B side different from that by 180 °
Alternatively, one or several sheets may be alternately supplied to each production line, or each lot may be supplied to the production line. Even in this case, the head element portion 42a for the A surface in which the direction of the magnetic field applied to the magnetic film differs by 180 ° according to exactly the same working method and working procedure.
And the head element portion 42b for the B side can be manufactured.

[0019]

According to the present invention, the direction of the applied magnetic field and the orientation of the ceramic substrate with respect to the direction of the applied magnetic field can be kept constant in the wafer process, and therefore, without changing the device, the jig, or the working method. Even if manufactured
When a magnetic film is formed on the head element portion and heat-treated, it is possible to apply magnetic fields in the respective necessary directions for the A side and the B side. Further, since the magnetization direction of the reading section reflects the orientation of the head element section, it is possible to immediately determine whether the head element section is for the A surface or the B surface when the wafer is viewed. As a result, there is no confusion at the manufacturing site, the work is not complicated, and the MR heads for the A side and the B side can be efficiently manufactured. As a result, the read unit can be incorporated so as to act in the same direction as the magnetization direction of the magnetic recording medium at any time, so that the characteristics of the hard disk device are not deteriorated.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of an example of an MR head.

FIG. 2 is an explanatory diagram showing an arrangement state of head element units in a wafer according to a conventional technique.

FIG. 3 is an explanatory diagram showing a positional relationship between a magnetic recording medium and an MR head, and a magnetization direction of a read section.

FIG. 4 is an explanatory diagram showing an example of an arrangement state of head element portions in a wafer according to the present invention.

FIG. 5 is an explanatory view showing another example of an arrangement state of head element parts in a wafer according to the present invention.

[Explanation of symbols]

 10 Ceramics Substrate 12 Reading Section 14 Writing Section 16 MR Film 20 Lower Shield 22 Upper Shield and Lower Magnetic Pole 28 Upper Magnetic Pole 32 Coil 40 Wafer 42 Head Element Section 42a Head Element Section for A Side 42b Head Element Section for Face B 60a A Forming area for surface 60b Forming area for surface B

Claims (4)

[Claims] 1. A write section having a MR film located between a lower shield and an upper shield and a gap film sandwiched between the lower magnetic pole and the upper magnetic pole and having a coil for generating a magnetic field therein. The head element part of the laminated structure,
In a wafer process of an MR head in which a large number of regularly arrayed elements are formed on a ceramic substrate, the direction of the applied magnetic field and the orientation of the ceramic substrate with respect to the direction of the applied magnetic field are applied when a magnetic field is applied during the MR film formation and the heat treatment. A hard disk characterized in that the orientations of the patterns of the head element portions arranged on the ceramic substrates are kept constant for all the ceramic substrates and are different by 180 ° between the A side and the B side of the magnetic recording medium. Method for manufacturing MR head for device. 2. The MR head for a hard disk drive according to claim 1, wherein a formation area for the A surface and a formation area for the B surface are mixed on one ceramic substrate in which the directions of the patterns of the head element parts are different by 180 °. Manufacturing method. 3. A method for applying a magnetic field not only when forming an MR film but also when forming all magnetic films and at the time of heat treatment.
The MR for a hard disk drive according to claim 1 or 2, wherein the direction of the applied magnetic field and the orientation of the ceramic substrate with respect to the direction of the applied magnetic field are kept constant for all the ceramic substrates.
Head manufacturing method. 4. The method for manufacturing an MR head for a hard disk drive according to claim 1, wherein the head element portion is a shared MR head that also serves as an upper shield of the reading portion and a lower magnetic pole of the writing portion.