JP2001110007A - Magnetic head and magnetic disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head which can increase a magnetic field that is generated at the tip of a write head by improving the efficiency of a magnetic circuit and decreasing the leaked magnetic flux. SOLUTION: The upper magnetic core of a magnetic head includes an upper magnetic core tip part 104 which is opposite to the surface of a recording medium and an upper magnetic core rear part 110 which is connected to the part 104. The rear end face of the part 104 is connected to the front end face of the part 110 to form a connection surface 114 on the extended surface of an insulating layer 103 that is prepared under a coil 107 or on a contact hole that is prepared at the back of the part 104 set on the extended surface of the layer 103. The surface 114 is formed substantially vertical to the surface of a substrate or at an angle of <=15 degrees to a surface that is parallel to the sliding surface of the magnetic head.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk device, and more particularly to a magnetic disk suitable for use as an external storage device of a computer, a method of manufacturing the same, and a magnetic disk device.

[0002]

2. Description of the Related Art With the advance of computer processing capability, it has become increasingly necessary to increase the storage capacity of magnetic disk devices. Along with this, the read head uses a magnetoresistive head or a giant magnetoresistive head to support high recording density and high speed processing. On the other hand, as the recording density increases, the coercive force of the recording medium also increases.
Supporting high recording density is an important issue.

For this reason, the track width and the distance between the gaps of the magnetic core of the magnetic head mounted on the magnetic disk device are becoming smaller, and the structure is also required to have higher precision.

In a magnetic head, the recording density is mainly determined by the shape of the tip of the magnetic core. In particular, the width of the upper magnetic core magnetic film that determines the track width, the overwrite, and the pole length that determines the resolution must be formed with high precision. Must.

[0005] Of these, in order to form the width d of the upper magnetic film with high precision, it is necessary to form the pattern of the upper magnetic film with high precision below the step of the insulating film. But,
If a photosensitive resin is applied to such a high stepped portion and formed, the thickness of the photosensitive resin at the lower part of the step becomes about 10 μm or more, so that there is a problem that a pattern cannot be formed with high precision. As a solution to this, a so-called upper magnetic core separation structure in which the upper magnetic core is manufactured by separating the upper magnetic core into a front end portion and an upper magnetic core rear portion is adopted.

[0006] With respect to the above forming method, see
10410, JP-A-2-247809, JP-A5-
182592, JP-A-6-76237, JP-A-6-76237
28626 and US-005285340
A etc. have been proposed.

[0007] These are characterized by a structure in which the rear portion of the upper magnetic core rides on the tip of the upper magnetic core.
Further, a magnetic film is formed in advance on the gap side of the top end of the upper magnetic pole (this is referred to as a notch structure), and the magnetic pole is mounted on the upper surface (Japanese Patent Laid-Open No. 7-296328).

In addition, as disclosed in Japanese Patent Application Laid-Open No. Hei 6-20227, there is a structure in which the rear surface of the upper magnetic core rides on the cut surface of the tip of the upper magnetic core. The structure is such that the coil layer and the insulating film layer are not distinguished.

[0009]

As the recording density increases, the coercive force of the recording medium increases. For this reason, the tip generated magnetic field required for the write head needs to have a higher value than before. For this purpose, it is conceivable to simply magnetize the material constituting the magnetic core to a high saturation magnetization.

However, if the efficiency of the magnetic circuit is low, the effect of using the high saturation magnetization material is expected to be small. The structure at the present time is basically optimized for low-density recording, and there is a possibility that a new structure corresponding to high recording density and high-speed processing may exist. However, basically, constructing a more efficient magnetic circuit is an important problem.

At the present time, the influence of the eddy current due to the high-frequency signal has already become larger than in the past, and it is necessary to consider means for reducing this.

In order to solve the above problem, there is a means for changing the material or structure of a magnetic circuit for performing recording (writing) of a magnetic head of a magnetic recording apparatus.

In order to enhance the magnetic field generated from the tip of the magnetic core (magnetic pole), it is conceivable to use a soft magnetic material having a high saturation magnetic flux density (Bs) for the magnetic material constituting the circuit.

The saturation magnetic flux density means the maximum amount of magnetic flux that can be occupied in a unit volume.
When this value is reached, a phenomenon occurs in which the magnetic flux stops flowing. The soft magnetic property means that the magnetization generated in the magnetic material changes linearly with respect to an external magnetic field and shows good reversibility. In particular, the use of a soft magnetic material having a high magnetic permeability with Bs for the magnetic core is effective in generating a strong magnetic field in the gap of the magnetic pole because a high magnetic flux density is generated in the magnetic pole with respect to the magnetic field generated in the coil. is there.

Further, since the recording signal changes the magnetization at a high frequency, an eddy current is generated in the magnetic pole. When this occurs, noise is generated in the signal, and an error may occur, the output may be reduced, or the high frequency characteristics may be adversely affected. In order to attenuate this, it is necessary that the material constituting the magnetic pole has a relatively high electric resistance or has a multilayer structure, and that the eddy current is attenuated.

As described above, from the viewpoint of a material that solves the required problem, a part or all of the magnetic core is made of a high Bs material, or a part or all of the magnetic core is made of a multilayer film. There is a means to make it.

On the other hand, when considering the strength of the magnetic field generated from the magnetic core, the more important condition is the structure of the magnetic circuit. In the first place, a write head is basically a state in which a magnetic field is applied or generated to a part of a magnetic body having a continuous structure, and a magnetic flux is induced in the magnetic body.
If a discontinuous gap is provided in a part of the structure, the permeability of the air occupying this gap is lower than that of a magnetic material. Is applied to perform writing.

The properties of the magnetic flux flowing in the magnetic circuit include:
There is a point that saturation is likely to occur where the cross-sectional area or material changes, and a point that magnetic flux is transmitted perpendicular to the boundary surface.

Here, considering the structure of the conventional upper magnetic core separated type write head, the upper magnetic core is separated into a top end of the upper magnetic core and a rear portion of the upper magnetic core. In this structure, the height of the part other than the magnetic core is very high,
The angle between the upper magnetic core tip and the horizontal plane was too steep. For this reason, the precision tends to vary in the manufacturing process, and it is difficult to solve the problem.

In view of the above, it is an object of the present invention to provide a magnetic head in which a write head has a larger magnetic field generated at the tip of a magnetic core than a conventional one, and a magnetic disk device using the same.

[0021]

In the above, the flat portion connecting the front end of the upper magnetic core and the rear portion of the upper magnetic core has a constant length, and the total thickness of this portion is large. As a result, magnetic flux leaks from the portion other than the tip to the lower magnetic core, and the efficiency of the magnetic circuit deteriorates. Also, since magnetic flux flows obliquely into the horizontally connected parts,
It is expected that the magnetic flux loss will be large at the interface. Therefore, it is considered that the magnetic field generated at the tip of the upper magnetic core has a certain limit.

In order to enhance the magnetic field generated at the tip of the magnetic core of the upper magnetic core separation structure, it is considered effective to minimize the loss at the connection portion. For this purpose, ideally, it should be good that the tip of the separated upper magnetic core and the rear of the upper magnetic core are magnetically continuous. Actually, the top end of the top magnetic core has a shape that connects to the back end of the top magnetic core, and the boundary between them has a shape that is orthogonal to the direction of magnetic flux flow. Is valid.

In the conventional type in which the connection portion is in the direction of the film surface, the length of the portion where the front end of the upper magnetic core and the rear portion of the upper magnetic core are in contact needs to have a certain length. That is, the length of the contacting portion cannot be changed.
For this reason, a magnetic field loss due to leakage of the magnetic field to the surroundings at the contact portion is considered. On the other hand, if the contact surface is taken in the direction perpendicular to the film surface, the length of the overlapped portion is reduced to the extent of the throw due to the difference in film thickness between the two. Thereby, the magnetic flux reaches the tip portion more effectively.

With respect to this structure, the magnetic field can be more effectively enhanced by using a high Bs material for the upper magnetic core and the lower magnetic core. In particular, in order to concentrate the magnetic flux in the gap portion of the magnetic core, the structure using a material having a high Bs in the portion in contact with the gap, or the processing (trimming) of the lower magnetic core in the manufacturing process is performed by the magnetic field of the upper magnetic core. It has become clear from the study of the present inventors that it is important to adjust the magnetic pole width so that is concentrated.

The gist of the present invention to achieve the above object is as follows.

[1] A lower magnetic core formed on a base, an upper magnetic core formed on the lower magnetic core and opposed to one end of the lower magnetic core via a magnetic gap, and a magnetic field between the two magnetic cores. In a magnetic head having a coil intersecting with a circuit, an upper magnetic core of the magnetic head has a tip of an upper magnetic core facing a recording medium surface, and a rear of an upper magnetic core connected to the tip of the upper magnetic core. Having a connection surface formed by connecting a rear end surface of the upper magnetic core front end portion and a front end surface of the upper magnetic core rear portion, on an insulating layer provided below the coil, and First
It is formed at the same height as the step, and the connection surface is
A magnetic head formed substantially perpendicular to a substrate surface or at an angle of 15 degrees or less with respect to a plane parallel to a sliding surface of the head.

[2] A lower magnetic core formed on the base, an upper magnetic core formed on the lower magnetic core and facing one end of the lower magnetic core via a magnetic gap, and a magnetic field between the two magnetic cores. In a magnetic head having a coil that intersects a circuit, an upper magnetic core of the magnetic head has a tip of an upper magnetic core facing a recording medium surface, and a rear of an upper magnetic core connected to the tip of the upper magnetic core. And a connection surface formed by connecting a rear end surface of the upper magnetic core front end portion and a front end surface of the upper magnetic core rear portion is on an extension surface of an insulating layer provided below the coil, or The connection surface is formed on a contact hole at the rear of the top end of the upper magnetic core on the extension surface, and the connection surface is substantially perpendicular to the substrate surface or 15 degrees with respect to a surface parallel to the sliding surface of the head. Formed at the following angles A magnetic head comprising:

[3] The magnetic head as described above, wherein the thickness of the connection surface is about の of the total thickness of the upper magnetic core tip and the upper magnetic core rear.

[4] The shape of the connection surface is such that the top end of the upper magnetic core is in contact with the insulating layer formed below the coil,
The above magnetic head, wherein the rear side of the upper magnetic core is formed so as not to contact.

[5] The magnetic head described above, wherein a side cross-sectional shape of the connection surface is L-shaped.

[6] The magnetic head as described above, wherein a connection surface between a rear end of the front end of the upper magnetic core and a front end of the rear of the upper magnetic core is on an insulating film provided on the lower magnetic core.

[7] The magnetic head as described above, wherein a part of the rear part of the upper magnetic core has a portion overlapping the upper surface of the tip of the upper magnetic pole.

[8] The rear end face of the top end of the upper magnetic core and the front end face of the rear part of the upper magnetic core are connected on a flat portion of the insulating film on the lower magnetic core, and the upper magnetic core on the flat portion is connected. The above magnetic head, wherein the sum of the lengths of the rear portion of the front end portion and the front end portion of the rear portion of the upper magnetic core is 5 μm or less.

[0034]

[9] The magnetic head, wherein a film thickness at a connection surface at a rear portion of the upper magnetic core is equal to or larger than a film thickness at a tip portion of the upper magnetic core.

[10] The rear portion of the upper magnetic core is a multilayer film, which is made of an electrically conductive material, Al ₂ O ₃ , Si
O ₂ , TiO ₂ , W ₂ O ₅ or a mixture thereof, or
The above magnetic head in which these nitrides are laminated.

[11] The magnetic head described above, which is made of a ferromagnetic material having an electrical resistivity at the rear of the upper magnetic core of 40 μΩcm or more at room temperature.

[12] The above magnetic head, wherein the tip of the upper magnetic core is made of a ferromagnetic material having an average saturation magnetic flux density of 0.8 Tesla or more at room temperature.

[13] The magnetic head, wherein the tip of the upper magnetic core is formed of a ferromagnetic multilayer film of two or more layers, and at least one of the layers has a saturation magnetic flux density of 1.3 to 2.3 Tesla at room temperature. .

[14] The ferromagnetic film contains nickel and iron as main components, and contains chromium, molybdenum, tungsten,
The above magnetic head containing 1 to 5 atomic% of at least one of vanadium, niobium, tantalum, titanium, zirconium and hafnium.

[15] At least one magnetic recording medium for recording information, a magnetic head for writing and reading information to and from the magnetic recording medium, a rotating means for the magnetic disk, and a positioning means for the magnetic head. A magnetic disk device provided with at least one head disk assembly having at least one magnetic head according to any one of the above [1] to [14].

[0041]

Embodiments of the present invention will be described below.

FIGS. 1 to 6 are schematic sectional views showing the structures of six representative examples of the upper magnetic core separated type head of the present invention. FIG. 7 is a schematic sectional view showing the structure of a conventional upper magnetic core separated type head.

First, the structure of the conventional upper magnetic core separated type head shown in FIG. 7 will be described. The top end portion 104 of the upper magnetic core and the coil portions 107 and 108 are laminated on the lower magnetic core 101, the gap film 102, and the insulating film 103 in this order from the substrate side (not shown). The core rear part 110 is laminated. A protective film 106 is provided on the top end portion 104 of the upper magnetic core.
The opening 109 provided in the upper magnetic core rear portion 110
Are superposed and magnetically connected. The material and size of each part will be described later.

On the other hand, the magnetic head of this embodiment is
The shape of the contact portion between the rear end of the upper magnetic core tip 104 and the upper magnetic core rear 110 is different.

In FIG. 1, a space is provided between the rear end 111 of the top end portion 104 of the upper magnetic core and the end portion 112 of each of the coil portions 107 and 108, and the rear portion 110 of the upper magnetic core fills this gap to form the rear portion of the upper magnetic core. The front end of 110 (surface 111)
It is connected to the rear end 111 of the top end portion 104 of the upper magnetic core by a surface (111 surface) having a cross section perpendicular to the film surface.

The structure of FIG. 2 is a structure in which the length of the flat portion (the distance between 111 and 112) near the rear end 111 of the top end portion 104 of the upper magnetic core is further reduced from the structure of FIG.

FIG. 3 shows a portion of the flat portion including the rear end 111 of the top end portion 104 of the upper magnetic core which is dug in to form a hole-shaped contact hole (between 111 and 112). This is a structure in which a part of the rear end 111 of the front end portion has penetrated into the insulating film.

FIG. 4 shows a structure in which the protective film 106 is not formed. Upper magnetic core rear 110 and lower magnetic core 1
The connection method with 01 may have different structures depending on the difference in the manufacturing method. Specifically, as shown in FIG. 4, the upper magnetic core rear part 110 and the lower magnetic core 101 are directly connected at the connection part 114, and as shown in FIGS. And the lower magnetic core 101 are connected to each other via a magnetic film formed at the connection portion 114. These production methods will be described later. In addition,
Other structures in FIG. 4 are the same as those in FIG.

FIG. 5 shows a coil unit 10 for generating a magnetic field.
7 and 108 show different structures. As described above, the number of steps differs only in the number of coil steps, whether it is one (FIG. 5) or two or more (FIG. 6). As the number of stages increases, the heights of the coil portions 107 and 108 increase accordingly, so that the efficiency of the magnetic circuit of the upper magnetic core rear portion 110 in the upper layer and the accuracy of the manufacturing process decrease. Usually, 2
Three stages are used.

FIG. 6 shows a case where the film thickness is the same at the joint (surface 111) between the top end portion 104 of the upper magnetic core and the rear portion 110 of the upper magnetic core and there is no step.

In other cases, the film thickness of the upper magnetic core rear portion 111 is larger than the film thickness of the upper magnetic core tip portion 104. For example, as shown in FIG. Have a structure that is superimposed (mounted) on the film surface of the top end portion 104 of the upper magnetic core.

In order to manufacture FIGS. 1 and 2, a manufacturing process of the upper magnetic pole separated type recording head shown in FIG. 8 can be mentioned.

After forming the lower magnetic core film 101 on the substrate 100, an insulating film 103 is formed, and a gap film 102 is formed. The order of forming the insulating film 103 and the gap film 102 may be reversed. This case is shown in FIG.

A pattern is formed on the gap film 102 using a photoresist to form the top end 104 of the upper magnetic core. After removing the pattern, the coil 10
7, 108 are formed. When the coil 107 is formed, a step of forming an insulating film as the protective film 106 on the top end portion 104 of the upper magnetic core may be included.

A pattern is formed on the rear end 111 of the top end portion 104 of the upper magnetic core, and the coils 107 and 108 are manufactured.
After the pattern is removed, a pattern is formed so that the upper magnetic core rear portion 110 can be formed.
0 is produced.

As another manufacturing method, a gap film 10 is formed on the lower magnetic core 101 as shown in FIG.
2, forming an insulating film 103, and forming a top end portion 104 of an upper magnetic core;
Is formed at the rear of the upper magnetic core rear part 110 at the same time as the connection part (114) with the lower magnetic core.

The upper magnetic core tip 104 is subjected to a process called trimming, a pattern is formed with a resist, and a protective film 106 is laminated. In this state, a flat portion is formed by chemical polishing.

The above chemical polishing treatment is performed in both cases where the protective film 106 remains on the flat portion at the rear of the top portion 104 of the upper magnetic core and when the flat portion at the back of the top portion 104 of the upper magnetic core is cut. Good. After the coils 107 and 108 are formed on the flat surface thus formed, the upper magnetic core rear portion 11 is formed.
0 is formed.

The manufacturing method of the magnetic head having the structure shown in FIGS. 3 to 6 is to form a protective film 106 on the top end portion 104 of the upper magnetic core, as shown in FIG. (FIB), a contact hole is formed by electron beam or pulsed electron beam irradiation. When the protective film 106 is present, the step of chemical polishing, which is a process for eliminating a step, may be performed before or after this.

When the upper magnetic core tip 104 and the other material are made of the same material, the magnetic field (maximum value of the in-plane component) generated at the tip of these magnetic heads is reduced by the dimension shown in FIG. The result obtained by the magnetic field calculation for the above-mentioned is a value as shown in the table of FIG. In this calculation, as shown in the parameter diagram of the calculation shown in FIG. 12, the upper magnetic core tip pole length 701 is 1 mm, the upper magnetic core tip rising angle 709 is 33 degrees, and the length of the rear flat part of the upper magnetic core tip is 33 degrees. 703 or 711 and 71
2, the total length was 5.5 μm (in the table, only the structure of FIG. 2 was 2 μm).
m), the rising angle 710 at the rear of the upper magnetic core is 45
5 (33 degrees in FIG. 5 for the structure in the table), the thickness of the tip portion 706 is 3 μm, the thickness of the lower magnetic core 704 is 3 μm, and the gap length 705 is 0.2 μm.

FIG. 13 shows the calculation results for the structures shown in FIGS. In addition, A to D indicate that when A is a magnetic material having Bs of 1T (tesla) as a material forming all the magnetic cores, B is Bs of which the tip of the upper magnetic core has a lower thickness of 1 μm by 1 μm. In the case of a multilayer film containing a 0.6T material, in addition to the case where C is B, Bs is 1.5 μm thick and 0.5 μm thick at the top of the lower magnetic core.
This is the case where there is a portion having a portion of 6T, and where D is a material having 1.6T Bs at the rear of the upper magnetic core.

As a result of a calculation using a computer, under the condition A, as can be seen from the table shown in FIG. 13, the structure of FIG.
The magnetic field generated at the distal end is slightly increased, and the magnetic field generated at the distal end is increased in the structure of FIG. It can also be seen that the generated magnetic fields of substantially the same magnitude are obtained for other structures.

However, with the recent high-density recording, it is desirable that the tip generated magnetic field be 6000 Oe (Oe) or more. Therefore, in order to obtain a higher generated magnetic field, a material having a high Bs is partially or entirely used. It is effective to use.

For example, under the condition B, a 1.6 T material is partially used for the tip of the upper magnetic core. In this case, the structures according to the present invention all obtain a magnetic field of 5000 Oe or more, and the And the same magnetic field is obtained. Each of the structures shown in FIGS. 1 to 6 exceeds the conventional type, and in particular, in the case of the structure shown in FIG. 2, the generated magnetic field is large, about 5250 Oe.

From the above, it can be seen that it is structurally effective to reduce the length of the upper flat portion. Also, in the case of the structure of FIG. 5, since the coil has one stage, the rising angle of the rear portion of the upper magnetic core is low, which indicates that it is effective.
Also, it is effective to use a material having a high Bs for the tip of the upper magnetic core as compared with the case of A.

Under the condition C, the lower magnetic core is partially increased in Bs in addition to the condition B. Thus, a structure in which the magnetic field is concentrated on the gap is expected. From the results, it is possible to generate a magnetic field of 6000 Oe or more in any of the structures. Although it is 6300 Oe in the conventional type, it is almost the same in the structure of FIG. 1 and 6500 Oe in the structure of FIG.
High magnetic field.

Further, Bs at the rear of the upper magnetic core is set to 1.6T.
, The results were almost the same as in the case of C. This is considered that the structures of the top end of the upper magnetic core and the lower magnetic core are not optimized. By optimizing these, a higher magnetic field can be generated. Further, in this case, in the conventional type, a leakage portion of the magnetic field may be generated on the way due to the length of the joining portion, and the efficiency may be reduced.

On the other hand, it has been found that the latter has a structure in which the magnetic field at the front end is slightly reduced and the loss of the magnetic field is small even if the rear portion is made of a high Bs material. Further, by using a material having a high resistance in this portion, it is possible to reduce the loss of the magnetic field output due to the eddy current.

In the conventional type, the tip of the upper magnetic core and the rear of the upper magnetic core are connected in the plane of the flat portion, and reducing the length of this portion is necessary to cause magnetic saturation at the connection. Impossible.

The fact that the length of the flat portion is long is as follows.
Since the portion where the upper magnetic core and the lower magnetic core are close to each other is long, the magnetic field leaks between the two poles, and the magnetic field generated from the tip of the magnetic core decreases.

On the other hand, in the present structure, as shown in the structure of FIG. 2, the length of the rear flat portion of the tip of the upper magnetic core can be reduced. The magnetic field generated when the calculated flat portion length changes changes as the flat portion becomes shorter, as shown in the graph of FIG.

The length of the portion where Bs is partially high in the lower magnetic core has an appropriate length depending on the structure as shown in the graph of FIG. 15, but in the case of the structure of FIG. It is understood that it takes. The structure shown in FIG. 3 corresponds to a case where the manufacturing method is changed, and can take the same value when the flat portion lengths are equal.

Further, it has been found that when the film thickness at the rear of the upper magnetic core is thicker than the tip of the upper magnetic core, it is effective to prevent the magnetic field saturation at the rear of the upper magnetic core.

The above results are calculated values.
When the magnetic head having the structure shown in FIG. 2 and the structure shown in FIG. 2 are manufactured and overwritten on the recording medium at two frequencies of f and 2f, the residual signal intensity of the structure of FIG. 1 is higher than that of the structure of FIG. It is low (about -40 dB), and an effective magnetic field is generated effectively. Good results have been obtained with other structures as well.

In order to cope with the current high recording density, this residual signal intensity ratio needs to be -30 dB or less, and as in the case of the calculated value, this structure is used as an effective magnetic field. It can be seen that this is an effective means for increasing the magnetic field of the part.

The above-mentioned effects are obtained because the flow of the magnetic flux in the upper magnetic core of the present structure has a constant direction and a smaller loss as compared with the case where the magnetic flux flows in contact with the rear horizontal plane at the tip of the upper magnetic core. This is because, by making contact in a plane perpendicular to the direction in which the magnetic flux flows, it is possible to prevent leakage of the magnetic field and maximize the transmission efficiency.

In the conventional type, with respect to the contact surface between the upper magnetic core tip and the upper magnetic core rear, the rear of the upper magnetic core tip may be located behind the contact surface, whereby the magnetic flux is partially generated. It is possible that the direction is reversed.
This reduces the magnetic flux reaching the magnetic core tip.
According to the structure of the present invention, since such a structure cannot be taken, the magnetic flux corresponding to this loss can be effectively used.

Further, in the conventional type, the tip of the upper magnetic core and the rear of the upper magnetic core overlap at the contact portion at the rear of the tip of the upper magnetic core. For this reason, the film thickness is partially increased, and the magnetic flux leaks outside due to the bent magnetic pole shape and the change in the film thickness. When the magnetic flux is saturated in the middle of the magnetic circuit structure, the transmission of the magnetic flux is not performed.

Therefore, it is important for the structure to minimize the change in film thickness and optimize the change in curvature. In the structure according to the present invention, the length of the flat portion can be reduced, so that the magnetic flux can be transmitted more effectively.

Further, in the structure of FIG. 2, the length of the flat portion surface at the rear of the tip of the upper magnetic core is shortened.
In the conventional type, the magnetic flux partially conducts between the upper magnetic core and the lower magnetic core in the flat portion, and the amount of magnetic flux reaching the tip of the magnetic core is low. By eliminating the flat portion, the magnetic flux effectively reaches the tip of the magnetic core.

In these structures, the structure of the tip of the upper magnetic core includes a structure in which a protective film is laminated and a structure without the protective film. This was selected depending on the manufacturing method and the properties of the materials used.

The tip of the upper magnetic core has at least two tips.
It has a structure in which more than one layer of magnetic material is stacked, and a part of the layer uses a material having a higher saturation magnetic flux density than other layers. The magnetic core is mainly made of a NiFe-based soft magnetic material, but the portion having a high saturation magnetization is, for example, Ni _x Fe _100-x (x = 40 to 6).
0) or a third element (Cr, Mo, Nb,
Ta, Ti, Zr, Hf) or CoNiF
e, etc., and Bs is 0.8 to 2.3T. For forming these, a plating method or a sputtering method was used.

As a material having a high resistivity, for example, Ni
_X Fe _100-X (x = 40-60) or the third
Using a compound of elements (Cr, Mo, Nb, Ta, Ti, Zr, Hf) or the like, it has been confirmed that the ratio of the third element has a value of 40 μΩcm or more in the range of 1 to 5 at%. .

For the protective film and the insulating film, a non-magnetic material having high insulating properties was mainly used. As an example, Al ₂ O ₃ or SiO
₂ , TiO ₂ , SiC or their nitrides, or
It is a film having a multilayer structure including these.

The material of the gap film is a film having non-magnetic insulating properties similar to those of the above-mentioned protective film and insulating film, or a non-magnetic metal film (Ta, Cr), and the above-mentioned non-magnetic material. It is a film having a laminated structure.

The write head in the above embodiment is
A magnetic head can be formed by combining it with a spin valve sensor, an MR head using the so-called anisotropic magnetoresistance effect, or a tunnel type GMR sensor as a read head, and can be applied for writing.

FIG. 16 is a configuration diagram showing an example of a magnetic disk device using the write head of the present invention. The write head according to the present invention is applied to a magnetic disk device as a magnetic recording device. However, the write head of the present invention can be applied to a magnetic recording device such as a magnetic tape device.

The illustrated magnetic disk device comprises a magnetic disk 1110, which is a magnetic recording medium, for recording data in a recording area called a concentric track, and a magnetic transducer, and reads and writes the data. A magnetic head 1118 to be implemented, actuator means for supporting the magnetic head and moving it to a predetermined position on the magnetic disk 1110, and control means for controlling transmission / reception of data read and written by the magnetic head 1118 and movement of the actuator means. Have.

At least one rotatable magnetic disk 1110 is supported by a rotating shaft 1112 and rotated by a driving motor 1114.

At least one slider 1116 has
The slider 11 is set on a magnetic disk 1110 and
16 is a magnetic head 11 for reading and writing
18 is supported.

At the same time as the magnetic disk 1110 rotates, the slider 1116 moves on the disk surface to access a predetermined position where the target data is recorded.

The slider 1116 is attached to the arm 1122 by a gimbal 1120.
0 is slightly elastic and makes the slider 1116 adhere to the magnetic disk 1110. The arm 1122 is attached to the actuator 1124.

As the actuator 1124, there is a voice coil motor (hereinafter, referred to as VCM). VCM
Is composed of a movable coil placed in a fixed magnetic field, and a moving direction and a moving speed of the coil are controlled by control means 1126.
And is controlled by an electrical signal provided via line 1130 from Therefore, the actuator means according to the present embodiment includes, for example, the slider 1116 and the gimbal 112.
0, an arm 1122, an actuator 1124, and a line 1130.

During the operation of the magnetic disk, the magnetic disk 11
The rotation of 10 creates an air bearing by airflow between slider 1116 and the disk surface, which causes slider 1116 to float above the surface of magnetic disk 1110. Therefore, during operation of the magnetic disk device, the air bearing balances the slight elastic force of the gimbal 1120 so that the slider 1116 floats without touching the surface of the magnetic disk and keeping a constant distance from the magnetic disk 1110. Is maintained.

Normally, the control means 1126 comprises a logic circuit, a memory, a microprocessor and the like, transmits and receives control signals via each line, and controls various constituent means of the magnetic disk device. For example, motor 1114 is controlled by a motor drive signal transmitted via line 1128. Actuator 1124 may control its associated magnetic disk 1110 via a line 1130, such as a head position control signal and a seek control signal.
The selected slider 1116 is controlled to move and position to the above target data track.

Then, the control means 1126 receives via the line 1132 and decodes the electric signal obtained by reading and converting the data of the magnetic disk 1110 by the magnetic head 1118. Further, an electric signal for writing as data on the magnetic disk 1110 is transmitted to the magnetic head 1118 via the line 1132. That is, the control means 1126
Controls transmission and reception of information read or written by the magnetic head 1118.

The above read or write signal can be transmitted directly from the magnetic head 1118. The control signals include, for example, an access control signal and a clock signal. Further, the magnetic disk device may include a plurality of magnetic disks and actuators, and the actuator may include a plurality of magnetic heads. By providing multiple functions in this way,
A disk array device can be formed.

[0098]

According to the present invention, it is possible to increase the magnetic field generated at the tip of the write head by improving the efficiency of the magnetic circuit and reducing the magnetic flux leakage. In addition, it is easy to introduce means for preventing the generation of eddy current, and a highly accurate head can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a recording head of the upper magnetic pole separation type according to the present invention.

FIG. 2 is a schematic cross-sectional view showing another example of the upper magnetic pole separated type recording head of the present invention.

FIG. 3 is a schematic cross-sectional view showing another example of the upper magnetic pole separated type recording head of the present invention.

FIG. 4 is a schematic cross-sectional view showing another example of the upper magnetic pole separated type recording head of the present invention.

FIG. 5 is a schematic cross-sectional view showing another example of the upper magnetic pole separated type recording head of the present invention.

FIG. 6 is a schematic cross-sectional view showing another example of the upper magnetic pole separated type recording head of the present invention.

FIG. 7 is a structural view of a conventional upper magnetic pole separation type recording head.

FIG. 8 is a schematic cross-sectional view showing an example of the manufacturing process of the upper magnetic pole separated type recording head of the present invention.

FIG. 9 is a schematic cross-sectional view showing an example of the manufacturing process of the upper magnetic pole separated type recording head of the present invention.

FIG. 10 is a schematic cross-sectional view showing an example of a manufacturing process of a recording head of an upper magnetic pole separation type.

FIG. 11 is a schematic cross-sectional view illustrating an example of a manufacturing process of an upper-pole-separated recording head.

FIG. 12 is a parameter diagram of calculation used in the embodiment.

FIG. 13 is a table showing a relationship between a magnetic field generated at the tip and various head structures.

FIG. 14 is a diagram showing the relationship between the magnetic field generated at the tip and the length of the flat portion.

FIG. 15 is a diagram illustrating a relationship between a magnetic field generated at a tip portion and a lower magnetic pole height Bs portion length.

FIG. 16 is a configuration diagram of a magnetic disk device of the present invention.

[Explanation of symbols]

100: substrate, 101: lower magnetic core, 102: gap film, 103: insulating film, 104: tip of upper magnetic core,
105: protective film, 106: protective film, 107: coil, 1
08: insulating film, 109: opening, 110: rear part of upper magnetic core, 111: rear part of upper magnetic core, 112: front end of coil part, 113: tip of a riding portion at the rear of the upper magnetic core, 114: connection part (top magnetic part) Rear of core rear), 70
1 ... Pole length at the top of the upper magnetic core, 702 ... Length of the rising portion of the top of the upper magnetic core, 703 ... Length of the rear flat portion at the top of the upper magnetic core (conventional type), 704 ... Film thickness of the lower magnetic core, 705 ... Gap length 706: Upper magnetic core tip thickness, 707: Upper magnetic core rear thickness, 708: Upper magnetic core tip rear thickness, 709: Upper magnetic core tip rising angle, 710: Upper magnetic core rear rising angle, 711, 712: length of the rear flat portion of the top end of the upper magnetic core, 1110: magnetic disk, 1112: rotating shaft,
1114 ... motor, 1116 ... slider, 1118 ...
Magnetic head, 1120 ... gimbal, 1122 ... arm,
1124 ... actuator, 1126 ... control means, 11
28, 1130 ... line.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kazue Kudo 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. Inside the Central Research Laboratory of the Works (72) Inventor Moriaki Fuyama 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo F-term in the Central Research Laboratory of Hitachi, Ltd. 5D033 BA07 CA02 DA02 DA31

Claims (15)

[Claims] A magnetic circuit is provided between a lower magnetic core formed on a base, an upper magnetic core formed on the lower magnetic core and facing one end of the lower magnetic core via a magnetic gap. A magnetic head having a coil that intersects with the magnetic head, wherein the upper magnetic core of the magnetic head includes a top end of the top magnetic core facing the recording medium surface, and a back end of the top magnetic core connected to the top end of the top magnetic core. A connection surface formed by connecting a front end surface of a rear end portion of the upper magnetic core with a rear end surface of the front end portion of the upper magnetic core,
The connection surface is formed on the insulating layer provided below the coil and at the same height as the first stage of the coil, and the connection surface is substantially perpendicular to the substrate surface or the head slides. A magnetic head formed at an angle of 15 degrees or less with respect to a plane parallel to the moving plane. 2. A lower magnetic core formed on a base, an upper magnetic core formed on the lower magnetic core, facing one end of the lower magnetic core via a magnetic gap, and a magnetic circuit between the two magnetic cores. A magnetic head having a coil that intersects with the magnetic head, wherein the upper magnetic core of the magnetic head includes a top end of the top magnetic core facing the recording medium surface, and a back end of the top magnetic core connected to the top end of the top magnetic core. A connection surface formed by connecting a front end surface of a rear end portion of the upper magnetic core with a rear end surface of the front end portion of the upper magnetic core,
The contact surface is formed on an extension surface of an insulating layer provided below the coil or on a contact hole at a rear portion of a tip of an upper magnetic core on the extension surface, wherein the connection surface is substantially perpendicular to a substrate surface. Or a magnetic head formed at an angle of 15 degrees or less with respect to a plane parallel to a sliding surface of the head. 3. The thickness of the connection surface is about の of the total thickness of the upper magnetic core tip and the upper magnetic core rear.
The magnetic head according to claim 1, wherein 4. The shape of the connection surface is such that the top side of the upper magnetic core is in contact with the insulating layer formed below the coil, and the rear side of the upper magnetic core is not in contact with the insulating layer.
Or the magnetic head according to 2. 5. The magnetic head according to claim 1, wherein a side cross-sectional shape of the connection surface is L-shaped. 6. The magnetic device according to claim 1, wherein a connection surface between a rear end of the front end portion of the upper magnetic core and a front end of the rear portion of the upper magnetic core is on an insulating film provided on the lower magnetic core. head. 7. A part of a rear portion of the upper magnetic core has a portion overlapping a top surface of a tip of an upper magnetic pole.
3. The magnetic head according to claim 1. 8. A top end of the upper magnetic core is connected to a front end surface of a rear portion of the upper magnetic core on a flat portion of the insulating film on the lower magnetic core, and a front end of the upper magnetic core on the flat portion is connected. The sum of the length of the front end of the rear of the part and the rear of the upper magnetic core is
3. The magnetic head according to claim 1, wherein the thickness is 5 μm or less. 9. The magnetic head according to claim 1, wherein a film thickness at a connection surface at a rear portion of the upper magnetic core is equal to or larger than a film thickness at a tip portion of the upper magnetic core. 10. The rear portion of the upper magnetic core is a multilayer film, which is made of an electrically conductive material, Al ₂ O ₃ , SiO ₂ , T
_3. The magnetic head according to claim 1, wherein iO ₂ , W ₂ O _5, a mixture thereof, or a nitride thereof is laminated. 11. The magnetic head according to claim 1, wherein an electrical resistivity of a rear portion of the upper magnetic core is made of a ferromagnetic material having a resistivity of 40 μΩcm or more at room temperature. 12. The magnetic head according to claim 1, wherein the tip of the upper magnetic core is made of a ferromagnetic material having an average saturation magnetic flux density of 0.8 Tesla or more at room temperature. 13. The magnetic head according to claim 1, wherein the tip of the upper magnetic core is formed of a ferromagnetic multilayer film having two or more layers, and at least one layer has a saturation magnetic flux density of 1.3 to 2.3 Tesla at room temperature. 3. The magnetic head according to claim 1. 14. The ferromagnetic film according to claim 1, wherein said ferromagnetic film contains nickel and iron as main components and at least one of chromium, molybdenum, tungsten, vanadium, niobium, tantalum, titanium, zirconium and hafnium in an amount of 1 to 5 atomic%. Item 14. The magnetic head according to item 12 or 13. 15. At least one magnetic recording medium for recording information, a magnetic head for writing and reading information on and from the magnetic recording medium, a rotating means for the magnetic disk, and a positioning means for the magnetic head. 15. A magnetic disk device provided with at least one head disk assembly, wherein at least one magnetic head according to claim 1 is mounted.