JPH06103533A - Thin-film magnetic head and its production - Google Patents

Abstract

PURPOSE:To decrease the noise to be generated and to prevent the shorting between electrode conductor layers by lowering the resistance of the electrode conductor layers for passing current to the magneto-resistance effect layer of the thin-film magnetic head. CONSTITUTION:The electrode conductor layers 2 are formed with at least >=3 layers of films and the specific resistance of the second layer electrode conductor layer 22 is set at <=5muOMEGA.cm. The first layer electrode conductor layer 21 is constituted as the layer in tight contact with the magneto-resistance effect layer 1 and the third layer electrode conductor layer 23 is formed as the layer in tight contact with the film thereon. The electrode conductor layers 2 are otherwise constituted of 4 layers of the films. The film of the uppermost layer is etched with a mask material, such as photoresist pattern, as a mask and the films of the lower layers are successively etched using this etched film as a mask material, thereby the generation of the projections of the resticking layer at the end of the electrode conductor layers is prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head used in a magnetic disk device and a manufacturing method thereof, and more particularly to a magnetoresistive thin film magnetic head and a manufacturing method thereof.

[0002]

2. Description of the Related Art A conventional magnetoresistive thin film magnetic head is a reproducing head which utilizes a phenomenon in which the electric resistance of a magnetoresistive film changes depending on the direction of magnetization. This magnetoresistive thin-film magnetic head is composed of a magnetoresistive element sandwiched between a lower magnetic shield made of a magnetic material and an upper magnetic shield. The magnetoresistive element is a magnetoresistive film and its magnetoresistive effect. By a bias film for applying a bias to the film, a magnetic domain control film for controlling the magnetic domains of the magnetoresistive film, and a film such as an electrode conductor film for supplying a current so that the magnetoresistive film acts as a sensor. Composed.

Conventionally, various electrode structures have been proposed for the electrode conductor film of the magnetoresistive thin film magnetic head. For example, Japanese Patent Publication No. 1-57511 discloses a thin-film magnetic head having an electrode conductor film composed of two layers. The first layer of this electrode conductor film structure is chromium, molybdenum, titanium, and the second layer. Has been shown to be composed of aluminum, gold, platinum, palladium, but details of its method of manufacture are not disclosed. Further, Japanese Patent Laid-Open No. 2-68706 discloses an electrode conductor film structure having two or three layers, in which an upper layer or an upper layer and a lower layer of a tungsten film are titanium, chromium, tantalum, zirconium,
A magnetoresistive thin-film magnetic head formed of a material selected from the group consisting of hafnium and titanium-tungsten alloy is disclosed, but a method of depositing an electrode conductor film is disclosed regarding its manufacturing method. However, it does not disclose a pattern forming method.
Further, JP-A-4-3306 discloses a magnetoresistive thin-film magnetic head using niobium, titanium, tantalum, gold, platinum, chromium, and alloy films thereof as an electrode conductor film. It is disclosed that a reactive dry etching method is applied as a method of etching the film of the above, but the resistance of the electrode conductor film is reduced and other films of the constituent film as the structural material of the electrode conductor film and the thin film magnetic head are No consideration is given to the adhesion strength of the.

[0004]

Although various electrode structures have been proposed for the electrode conductor film of the magnetoresistive thin film magnetic head in the above-mentioned prior art, it is necessary to reduce the resistance of the electrode conductor film and Margins for actual mass production are not sufficient, considering problems such as damage to other films during etching to form patterns and adhesion with other films when creating magnetoresistive elements. However, there was a problem that it was small and stable production was not possible.

The object of the present invention is to reduce the resistance of the electrode conductor film for passing a current through the magnetoresistive film to reduce the noise generated, and to perform the track width machining with high accuracy, which is effective for the electrode conductor film. It is an object of the present invention to provide a magnetoresistive thin film magnetic head having an electrode structure capable of preventing a short circuit between them and a manufacturing method thereof.

[0006]

In order to achieve the above object, a magnetoresistive thin-film magnetic head and a method of manufacturing the same according to the present invention include a magnetoresistive layer element portion including a magnetoresistive film, and at least 2. And a plurality of electrode conductor layers, each electrode conductor layer being in contact with the thin film of the magnetoresistive effect layer element portion at a position spaced apart from each other to be electrically connected. The layer is composed of at least three layers, and at least one of them has a specific resistance of 5 or less.
By using a film having a resistance of μΩ · cm or less, the film has low resistance and sufficient adhesion to form a magnetoresistive thin-film magnetic head, and an electrode that requires an accurate pattern. Regarding the spacing between the conductor layers, the first layer of the electrode conductor layer is composed of a film of niobium, tantalum, titanium, molybdenum, chromium, or an alloy of these metals, and the second layer of the electrode conductor layer is gold, silver, or It is composed of a film of copper, aluminum or an alloy of these metals, and the third layer of the electrode conductor layer is composed of a film of niobium, tantalum, titanium, molybdenum, chromium, nickel, iron, cobalt or an alloy of these metals. At the same time, a film composed of niobium, tantalum, titanium, molybdenum, chromium, or an alloy of these metals is formed as a fourth layer on these constituent films. By sequentially etching these films, a thin film magnetic head having an electrode conductor layer formed with high precision can be obtained.

[0007]

In the magnetoresistive thin-film magnetic head and the method for manufacturing the same, the electrode conductor layer for passing a current through the magnetoresistive layer is composed of at least three layers, one of which is
By setting the specific resistance of the layer to 5 μΩ · cm or less, a low resistance electrode conductor layer can be formed, and the low resistance is 5 μΩ · cm.
By forming the following metal film from gold, silver, copper, aluminum, or an alloy of these metals, a low-resistance electrode conductor layer is formed. In addition, the electrode conductor layer is composed of at least three or more layers to secure the adhesion and conductivity between the electrode conductor layer and the magnetoresistive effect layer, and the electrode conductor layer and the thin film magnetic head formed on the electrode conductor layer. Niobium, tantalum, titanium, molybdenum, chromium, or a metal of these can be used as a film that can secure the adhesiveness with the constituent materials and secure the adhesiveness and conductivity between the electrode conductor layer and the magnetoresistive effect layer. It is possible to secure the adhesion and conductivity with the magnetoresistive layer by using the alloy film of, and also the adhesion between this electrode conductor layer and the material that composes the thin film magnetic head formed on it. By forming a film of niobium, tantalum, titanium, molybdenum, chromium, nickel, iron, cobalt, or an alloy of these metals as a film to be formed on the electrode conductor layer. Adhesion to the material to be made can be secured. In addition, the electrode conductor layer is formed of a film having a four-layer structure, the uppermost film is etched using a mask material such as a photolithic pattern as a mask, and the lower film is sequentially etched using this film as a mask material. Thus, it is possible to prevent the protrusion of the reattachment layer from being generated at the end of the electrode conductor layer. Further, when the electrode conductor layer is composed of a film having a four-layer structure, by using a film in which the uppermost film and the lowermost film can be simultaneously etched, at least the electrode conductor layer at the contact portion with the magnetoresistive effect layer is used. Can have a three-phase structure.

[0008]

Embodiments of the present invention will be described below with reference to FIGS. 1A and 1B are a perspective view and a sectional view of a magnetoresistive effect layer element portion and an electrode conductor layer showing a first embodiment of a magnetoresistive effect thin film magnetic head according to the present invention. 1A and 1B, an outline of the configuration of the magnetoresistive thin-film magnetic head is shown in FIG. 1A, in which an insulating film such as alumina is formed on a ceramic substrate, which is not shown in the drawing, and a nickel film is formed on the insulating film. A lower shield film formed of a magnetic film such as iron and an alloy film is formed, and an insulating film such as alumina is further formed on the lower shield film, and then the magnetoresistive effect layer element portion 1 shown in the figure is formed. Has been done. The magnetoresistive effect layer element portion 1 is, of course, formed with a magnetoresistive effect film acting as a sensor, but biases of various known means which can constitute means for applying an appropriate bias to the magnetoresistive effect film. The fact that the films are simultaneously formed and that the magnetic domain control layer for controlling the magnetic domains of the magnetoresistive film is also simultaneously formed do not limit the present invention. On the magnetoresistive layer element portion 1 thus formed, the electrode conductor layer 2 which plays a role of supplying a current for acting as a sensor is formed, and an alumina conductor (not shown) is formed thereon. And the like, a shield film on the top formed of a magnetic film such as an alloy film of nickel and iron is formed thereon, and an insulation film such as alumina as a protective film is further formed thereon. There is.

As shown here, the electrode conductor layer 2 according to the present invention includes a first layer electrode conductor layer 21 and a second layer electrode conductor layer 2.
2 and a third-layer electrode conductor layer 23, at least three layers of which are included. The first-layer electrode conductor layer 21 is a film constituting the magnetoresistive effect layer of the magnetoresistive effect layer element part 1; Adhesiveness with the second layer electrode conductor layer 22 and the second layer electrode conductor layer 2
2 is a film having a specific resistance of 5 μΩ · cm or less, and the third-layer electrode conductor layer 23 is an adhesion layer between the second-layer electrode conductor layer 22 and the film forming the thin-film magnetic head formed on the electrode conductor layer 2. is there. As a film forming these electrode conductor layers 2, for example, a niobium film is used as the first layer electrode conductor layer 21, a gold film is used as the second layer electrode conductor layer 22, and a chromium film is used as the third layer electrode conductor layer 23. be able to. Here, the niobium film of the first-layer electrode conductor layer 21 plays a role of bringing the electrode conductor layer 2 into close contact with the magnetoresistive effect film element portion 1 to supply a current directly to the magnetoresistive effect film element portion 1. The gold film of the two-layer electrode conductor layer 22 has a low specific resistance of gold and is preferably 5 μΩ · c.
Since it is less than or equal to m, it is used to lower the overall electric resistance of the electrode conductor layer 2 and thus serves to provide the electrode conductor layer 2 with low resistance. However, the gold film of the second electrode conductor layer 22 has poor adhesion to the insulating film such as alumina formed on the electrode conductor layer 2, and therefore the second electrode conductor layer 22 is formed there.
A chromium film as the third electrode conductor layer 23 is formed on the gold film to improve the adhesion between the electrode conductor layer 2 and an insulating film such as alumina formed thereon. Here, the chromium film is used as the third-layer electrode conductor layer 23 because it is a metal film that not only secures conductivity but also has high adhesion.

FIGS. 2A to 2F are sectional views showing the steps of forming an electrode conductor layer showing the first embodiment of the method of manufacturing a magnetoresistive thin film magnetic head according to the present invention. Figure 2 (a)
Processes for forming the electrode conductor layer with a four-layer structure in the method of manufacturing the magnetoresistive thin film magnetic head will be described with reference to (f). First, after the magnetoresistive effect layer element portion 1 is formed as shown in FIG. 2A, a niobium film of the first-layer electrode conductor layer 21, a gold film of the second-layer electrode conductor layer 22, and a third film A chromium film of the layer electrode conductor layer 23 is sequentially formed, and, for example, a niobium film is formed as the fourth layer electrode conductor layer 24 on the chromium film.
The layer electrode conductor layer 24 is not shown in the configuration diagram of the magnetoresistive effect layer element portion and the electrode conductor layer of FIGS. 1A and 1B, and is etched in the step of forming the electrode conductor layer 2 as described later. It is also used as a mask material when forming a pattern by the method. Next, as shown in FIG. 2B, a photoresist pattern 3 used as a mask material for forming the pattern of the electrode conductor layer 2 is formed on the fourth-layer electrode conductor layer 24. Then, as shown in FIG. 2C, the niobium film of the fourth-layer electrode conductor layer 24 is etched using the photoresist pattern 3 as a mask. The etching method at this time may be a wet etching method, but since the distance between the two electrode conductor layers 2 defines the distance through which the current of the magnetoresistive effect layer element portion 1 flows, that is, the distance acting as a sensor, strict accuracy is required. It is necessary to create a pattern with, and the wet etching method is not sufficient to secure the accuracy, and the dry etching method is suitable. CF here
Regarding the fact that it is possible to selectively etch a niobium film by a parallel plate type plasma etching method using a gas in which ₄ and oxygen are mixed, the above-mentioned JP-A-4-33.
No. 06 publication, this method is applied to
The niobium film of the layer electrode conductor layer 24 is etched as intended, and the selection ratio of the lower third layer electrode conductor layer 23 to the chromium film is 5 or more, so that the lower layer chromium film is hardly damaged. It turned out that etching is possible.

Subsequently, as shown in FIG. 2D, the photoresist pattern 3 is removed, whereby the third-layer electrode conductor layer 2 is removed.
The pattern of the niobium film of the fourth electrode conductor layer 24 is formed on the chromium film 3 of No. 3, and this pattern of the niobium film serves as a mask material in the next etching step. As a method for etching the gold film of the second electrode conductor layer 22, a dry etching method by a physical method such as an ion beam etching method or a sputter etching method is adopted. Then, as shown in FIG. 2C, the fourth electrode conductor layer 24 is formed by, for example, an ion beam etching method using argon gas.
The chrome film of the third-layer electrode conductor layer 23 and the gold film of the second-layer electrode conductor layer 22 are continuously etched using the pattern of the niobium film as a mask. At this time, the two layers are continuously etched. For example, only the chromium film of the third electrode conductor layer 23 may be previously etched by the parallel plate type plasma etching method using a chlorine-based gas, which is not an essential condition. Now, when the ion beam etching method is used, when etching the gold film of the second electrode conductor layer 22, it is necessary to add overetching at a constant rate in order to eliminate etching residue in addition to a predetermined time. However, if this over-etching becomes excessive, the niobium film of the lower first electrode conductor layer 21 may be removed by etching, and the lower magnetoresistive effect layer element part 1 may be damaged. Therefore, the amount and time of the over-etching are optimized and the first-layer electrode conductor layer 21 is
By optimizing the thickness of the niobium film, the gold film of the second-layer electrode conductor layer 22 is of course completely removed at the time of this ion beam etching, but the niobium film of the first-layer electrode conductor layer 21 is over-etched. It is necessary to ensure that even if it is slightly etched, it remains on the lower magnetoresistive layer element portion 1 as shown in the figure.
Next, as shown in FIG. 2F, the niobium film of the first-layer electrode conductor layer 21 is removed. This is performed by the parallel plate type plasma etching method using the gas in which CF ₄ and oxygen are mixed as described above. According to this, it is possible to selectively etch the niobium film, and this method may be adopted. At this time, over-etching for removing the niobium film of the first-layer electrode conductor layer 21 is applied to the upper surface of the lower magnetoresistive effect layer element portion 1, but the surface uses a gas in which CF ₄ and oxygen are mixed. There is no problem if it is a material that can be etched by the parallel plate type plasma etching method, but in the case of a material that is etched, a film of a material that is difficult to be etched, such as chromium, nickel, or an alloy containing these, is formed on the surface. It is necessary to form it. At the same time as this etching, the niobium film of the fourth-layer electrode conductor layer 24 is also removed by etching during this etching. Through the above steps, the electrode conductor layer 2 of the magnetoresistive thin-film magnetic head shown in FIGS. 1A and 1B is formed.

FIG. 3 is a perspective view showing the structure of a magnetoresistive effect layer element portion and an electrode conductor layer showing another embodiment of the magnetoresistive effect type thin film magnetic head according to the present invention. FIG. 3 shows an example in which the niobium film of the fourth-layer electrode conductor layer 24 is completely removed by etching in the process of forming the electrode conductor layer 2 in the above-described embodiment, so that the electrode conductor layer 2 has a three-layer structure. However, in this embodiment, a part of the niobium film of the fourth-layer electrode conductor layer 24 is removed by etching, and a part of the electrode conductor layer 2 has a three-layer structure, while the other part is a third-layer electrode conductor. It is possible to leave it on the layer 23, and as shown in the figure, the magnetoresistive layer element part 1
An example is shown in which the niobium film of the fourth-layer electrode conductor layer 24 is left on the wiring leading portion behind the connection portion of the electrode conductor layer 2 and the electrode conductor layer 2.

4 (a), (b) and (c) are cross-sectional views of a process for forming a wiring lead portion of an electrode conductor layer showing another embodiment of the method of manufacturing a magnetoresistive thin film magnetic head according to the present invention. It is a figure. 4A, 4B, and 4C, a process of forming a wiring lead portion of the electrode conductor layer in the method of manufacturing the magnetoresistive thin film magnetic head will be described. This step can be carried out only by adding a step of forming a photoresist pattern to the steps shown in FIGS. 2A to 2F. First, in FIG. 4A, in the step of FIG. The cross section of the wiring lead-out portion of the electrode conductor layer is shown, and in this figure, the wiring lead-out portion of the electrode conductor layer 2 is formed on the substrate 10. Here, as shown in FIG. 4B, the photoresist pattern 4 is formed only on the wiring leading portion of the electrode conductor layer 2. Then, as shown in FIG. 4C, the niobium film of the first-layer electrode conductor layer 21 is removed in the step of FIG. 2F, and the photoresist pattern is formed on the wiring leading portion of the electrode conductor layer 2. 4 is formed, the niobium film of the fourth electrode conductor layer 24 thereunder remains at the same time without being removed. Then, if the photoresist pattern 4 is removed, FIG.
The structure of the electrode conductor layer 2 as shown in FIG. In this embodiment, the photoresist pattern 4 is formed only on the wiring lead-out portion of the electrode conductor layer 2 already formed, but the electrode conductor layer already formed within a range in which the two electrode conductor layers 2 are not short-circuited with each other. It is also possible to form it wider than the second wiring lead portion.

FIG. 5 is a perspective view showing the structure of a magnetoresistive effect layer element portion and an electrode conductor layer showing still another embodiment of the magnetoresistive effect type thin film magnetic head according to the present invention. In FIG. 5, in the above-described embodiment, the fourth layer electrode conductor layer 2 of the electrode conductor layer 2 is formed on the magnetoresistive effect layer element portion 1 of the thin film magnetic head.
However, in the present embodiment, the entire electrode conductor layer 2 has a four-layer structure, except for the fourth layer electrode conductor layer 24 of the electrode conductor layer 2 which is also left above the magnetoresistive effect layer element portion 1. In this example, the magnetoresistive effect is obtained by forming the electrode conductor layer 2 of this embodiment on the entire electrode conductor layer 2 by changing the shape of the photoresist pattern 4 in the step shown in FIG. 4B. It is possible to leave the fourth-layer electrode conductor layer 24 of the electrode conductor layer 2 on the layer element portion 1 as well.

FIG. 6 is a structural cross-sectional view of a current supply portion of a wiring lead-out portion of an electrode conductor layer showing still another embodiment of the magnetoresistive thin film magnetic head according to the present invention. In FIG. 6, in order to supply a current to the electrode conductor layer 2 described above, it is necessary to form a current supply part in a part of the wire routing part, and this current supply part is formed on a part of the wire routing part. Since it is created by stacking another conductive film on
Therefore, the third layer electrode conductor layer 23 of the electrode conductor layer 2 or the third layer
This means that the layer electrode conductor layer 23 and the fourth layer electrode conductor layer 24 are wired in series in the film thickness direction, where the third layer electrode conductor layer 23 or the third layer electrode conductor layer 2 in the current supply portion is located.
It is effective to make the third and fourth layer electrode conductor layers 24 thin, and for that reason, the third layer electrode conductor layer 2 in the portion of the current supply portion is used.
3 or third layer electrode conductor layer 23 and fourth layer electrode conductor layer 24
It is appropriate to have a structure in which a part or all of the above is laminated and then another conductive film is laminated. Therefore, as an example at this time, after the third layer electrode conductor layer 23 is removed by etching, another conductive film is formed. FIG. 6 shows an example of the case where the current supply portion 7 on the electrode conductor layer 2 is formed by stacking 6 layers. As described above, after forming the electrode conductor layer 2, the insulating film 5 made of alumina or the like is formed, and thereafter the upper shield film is laminated. Therefore, removing the third-layer electrode conductor layer 23 by etching does not require any additional step, but by adding appropriate over-etching in the step of forming a through hole in the insulating film 5 made of alumina or the like, the third portion of the third layer is simultaneously removed. The layer electrode conductor layer 23 can be removed by etching, whereby the wiring resistance of the wiring leading portion of the electrode conductor layer 2 can be reduced as much as possible.

In the above embodiment, one kind of material is used for each of the first-layer electrode conductor layer 21 to the fourth-layer electrode conductor layer 24 constituting the electrode conductor layer 2 of the magnetoresistive thin-film magnetic head. However, other materials can be used as shown below. That is, although the first-layer electrode conductor layer 21 has been described as a niobium film, other than this, a film of tantalum, titanium, molybdenum, chromium, or an alloy of these metals can be used, and the etching is performed with good adhesion and selectivity. It is possible to The second-layer electrode conductor layer 22 has a low resistance in order to reduce the resistance of the wiring lead-out portion of the electrode conductor layer 2 and to reduce the unevenness caused by the electrode conductor layer 2 on the magnetoresistive effect layer element portion 1. It is necessary and the material has a specific resistance of 5 μΩ · c.
It is preferably m or less, and can be composed of silver, copper, aluminum, or an alloy of these metal films in addition to gold described in the above embodiment. The third-layer electrode conductor layer 23 has been described as a chromium film, but a film of a material that can ensure the adhesiveness with the second-layer electrode conductor layer 22 and the adhesiveness with the film formed on the electrode conductor layer 2. However, the first electrode conductor layer 21 may be made of tantalum, titanium, molybdenum, niobium, nickel, iron, cobalt, or an alloy of these metal films or an oxide film. It is desirable that the first-layer electrode conductor layer 21 and the third-layer electrode conductor layer 23 are not films of the same material so that these films are not etched when etching is performed. Although the fourth electrode conductor layer 24 has been described as a niobium film, a film of tantalum, titanium, molybdenum, chromium, or an alloy of these metals is used in addition to this, and is configured to be etched with good adhesion and selectivity. It is desirable that the first layer electrode conductor layer 21 and the first layer electrode conductor layer 21 are simultaneously etched when the first layer electrode conductor layer 21 is etched. Therefore, the same material as the first layer electrode conductor layer 21 or a material that is simultaneously etched by the same etching method is used. Is desirable. With respect to the etching of the first-layer electrode conductor layer 21 and the fourth-layer electrode conductor layer 24, the application of the parallel plate type plasma etching method using a gas in which CF ₄ and oxygen are mixed is described in the above embodiment. , Eg CHF
It is needless to say that the gas can be used if the films of the first-layer electrode conductor layer 21 and the fourth-layer electrode conductor layer 24 can be etched even if another gas containing fluorine such as ₃ is used. Is.

7 (a) to 7 (e) are cross-sectional views of a process of forming an electrode conductor layer showing a second embodiment of the method of manufacturing a magnetoresistive thin film magnetic head according to the present invention. Figure 7 (a)
The steps of forming the electrode conductor layer with a three-layer structure in the method of manufacturing the magnetoresistive thin film magnetic head will be described with reference to (e). First, as shown in FIG. 7A, the magnetoresistive effect layer element 1
After the formation, the niobium film of the first-layer electrode conductor layer 21, the gold film of the second-layer electrode conductor layer 22, and the chromium layer of the third-layer electrode conductor layer 23 are sequentially formed thereon. Next, as shown in FIG. 7B, a photoresist pattern 3 used as a mask material for forming the pattern of the electrode conductor layer 2 is formed on the third-layer electrode conductor layer 23. Then, as shown in FIG. 7C, the chromium film of the third-layer electrode conductor layer 23 and the gold film of the second-layer electrode conductor layer 22 are subjected to an ion beam etching method using, for example, argon gas by using the photoresist pattern 3 as a mask. Etch continuously. At this time, it is not essential to continuously etch the chromium film of the third-layer electrode conductor layer 23 and the gold film of the second-layer electrode conductor layer 22, and for example, only the chromium film of the third-layer electrode conductor layer 23 is etched. It is also possible to perform etching by a parallel plate type plasma etching method using a chlorine-based gas. The first underlayer film at this time
The overetching of the layer electrode conductor layer 21 is the same as the step shown in the first embodiment, but at this time, the important point is that a redeposition layer adheres to the side wall of the photoresist film of the photoresist pattern 3 during etching. Is how to prevent this. The redeposited layer is, for example, a gold film of the second electrode conductor layer 22 in this embodiment, a material that is etched during ion beam etching is sputtered during etching, and the material is a photoresist pattern 3 that is a mask material. It adheres to the side wall of the photoresist film of and grows into protrusions like corners in the sectional structure. When such a re-adhesion layer is generated at the end portion of the electrode conductor layer 2, the thickness of the insulating film formed on the electrode conductor layer 2 is locally thinned and sufficient insulation cannot be ensured, and the redeposition layer is formed thereon. Since the problem that the electrode conductor layer 2 is short-circuited through the upper shield film occurs, it is important to optimize the film thickness and cross-sectional shape of the resist pattern 3 in order to prevent this. On the other hand, when the fourth-layer electrode conductor layer 24 is used as the ion milling mask material as shown in the first embodiment, there is almost no problem with respect to the occurrence of the redeposited layer. Next, FIG. 7 (d)
As shown in FIG. 7, the first-layer electrode conductor layer 21 is etched, and then the photoresist pattern 3 is removed as shown in FIG. 7E, whereby the electrode conductor layer 2 as shown in the drawing is formed.
According to the present embodiment, since the film for forming the electrode conductor layer 2 may be three layers, there is an advantage that the film structure is simplified, and the first layer electrode conductor layer and the third layer electrode conductor layer are formed. Since films of the same material can be used, in this case, there is also an advantage that the film constituent material can be simplified.

In the above-mentioned embodiments, the structure of the electrode conductor layer and the manufacturing process thereof have been described for the magnetoresistive thin film magnetic head, but it goes without saying that the head is composed of only the magnetoresistive thin film magnetic head. But,
It goes without saying that the present invention can also be applied to a recording / reproducing separated composite head in which a read-only magnetoresistive head and a write magnetic induction head, for example, are combined.

[0019]

As described in detail above, according to the present invention, the electrode conductor layer of the magnetoresistive thin-film magnetic head is composed of at least three layers, and at least one of them has a specific resistance. By setting the resistance to 5 μΩ · cm or less, a low resistance electrode conductor layer can be formed, and thus a low noise magnetoresistive thin film magnetic head with less noise generated from the electrode conductor layer can be provided. In addition, the electrode conductor layer is formed of a film having a four-layer structure, the uppermost film is etched by using a mask material such as a photoresist pattern as a mask, and the lower film is sequentially etched by using this film as a mask material. , It is possible to prevent the occurrence of protrusions of the reattachment layer at the end portion of the electrode conductor layer, and thus to prevent the short circuit between the electrode conductor layers due to the occurrence of this reattachment layer. is there.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electrode conductor layer according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a process of forming an electrode conductor layer.

FIG. 3 is a diagram showing a configuration of an electrode conductor layer according to another embodiment of the present invention.

FIG. 4 is a diagram showing a process of forming a current routing portion of an electrode conductor layer.

FIG. 5 is a configuration diagram of an electrode conductor layer according to still another embodiment of the present invention.

FIG. 6 is a diagram showing a current supply portion of an electrode conductor layer according to still another embodiment of the present invention.

FIG. 7 is a diagram showing a process of forming an electrode conductor layer according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetoresistive layer element part, 2 ... Electrode conductor layer, 3 ... Photoresist pattern, 4 ... Photoresist pattern, 5 ... Insulating film, 6 ... Conductive film, 7 ... Current supply part, 10 ... Substrate,
21 ... 1st layer electrode conductor layer, 22 ... 2nd layer electrode conductor layer, 2
3 ... 3rd layer electrode conductor layer, 24 ... 4th layer electrode conductor layer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsunori Owada 2880 Kokuzu, Odawara, Kanagawa Stock company Hitachi Ltd. Odawara factory (72) Inventor Tetsuo Kobayashi 2880, Kokuzu, Odawara, Kanagawa Hitachi Odawara factory (72) Inventor Shinji Shigeshi 2880 Kozu, Odawara-shi, Kanagawa Stock company Hitachi Ltd. Odawara factory (72) Inventor Shigeru Tadokoro 4026 Kujicho, Hitachi City, Ibaraki Hitachi Research Laboratory, Hitachi Ltd.

Claims (4)

[Claims] 1. A magnetoresistive effect thin film magnetic head having at least a magnetoresistive effect layer and an electrode conductor layer for passing a current through the magnetoresistive effect layer, wherein the electrode conductor layer is composed of three layers or four layers. The first layer of the layers is an adhesion layer between the film forming the magnetoresistive effect layer and the second layer of the electrode conductor layer, and the second layer of the electrode conductor layer is a film having a specific resistance of 5 μΩ · cm or less, When the conductor layer is composed of three layers, the third layer of the electrode conductor layer is an adhesion layer between the second layer of the electrode conductor layer and the film forming the thin film magnetic head formed on the electrode conductor layer, and When the electrode conductor layer is composed of four layers, the third layer of the electrode conductor layer is an adhesion layer between the second layer of the electrode conductor layer and the fourth layer of the electrode conductor layer, and the fourth layer of the electrode conductor layer is It is an adhesion layer between the third layer of the electrode conductor layer and the film forming the thin film magnetic head formed on the electrode conductor layer. Thin-film magnetic head according to. 2. A first layer of the electrode conductor layer is composed of a film of niobium, tantalum, titanium, molybdenum, chromium or an alloy of these metals, and a second layer of the electrode conductor layer is gold, silver,
It is composed of a film of copper, aluminum or an alloy of these metals, and the third layer of the electrode conductor layer is composed of a film of niobium, tantalum, titanium, molybdenum, chromium, nickel, iron, cobalt or an alloy of these metals. The thin film magnetic head according to claim 1, wherein the fourth layer of the electrode conductor layer is formed of a film of niobium, tantalum, titanium, molybdenum, chromium, or an alloy of these metals. 3. The method of manufacturing a thin film magnetic head according to claim 2, wherein when the electrode conductor layer is composed of three layers, a mask material such as a photoresist pattern is provided on the third layer of the electrode conductor layer. Is used as a mask to etch the third layer of the electrode conductor layer, and this is used as a mask to etch the second layer of the electrode conductor layer. Then, the first layer of the lowermost electrode conductor layer is etched by the reactive dry etching method. When the electrode conductor layer is composed of four layers, a mask material such as a photoresist pattern is provided on the fourth layer of the electrode conductor layer, and the fourth layer of the electrode conductor layer is etched by using this as a mask. Using this as a mask, the third layer of the electrode conductor layer is etched, then the second layer of the electrode conductor layer is etched, and then the first layer of the lowermost electrode conductor layer is etched by the reactive dry etching method. hand The electrode conductor layer has a four-layer structure, or the fourth layer of the electrode conductor layer is partially or entirely etched and removed simultaneously with or after the first layer of the lowermost electrode conductor layer is etched. By doing so, a part or all of the electrode conductor layer has a three-layer structure, and a method of manufacturing a thin-film magnetic head. 4. When the electrode conductor layer is composed of three layers, a reactive dry etching method or an ion beam etching method is used for etching the third layer of the electrode conductor layer, and the second layer of the electrode conductor layer is etched. The ion beam etching method is used for etching, the reactive dry etching method is used for etching the first layer of the electrode conductor layer, and the fourth layer of the electrode conductor layer is used when the electrode structure is composed of four layers. The reactive dry etching method is used for etching, the ion beam etching method is used for etching the third layer of the electrode conductor layer and the second layer of the electrode conductor layer, and the first layer of the electrode conductor layer is etched for etching. 4. The method for manufacturing a thin film magnetic head according to claim 3, wherein the reactive dry etching method is used.