JP2004335095A - Thin film magnetic head and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a magnetic pole part of an induction electromagnetic conversion element with high accuracy and to prevent the data from being written in an area other than the area to record. <P>SOLUTION: A recording head has a lower magnetic pole layer 10, a thin film coil 13, a recording gap layer 17 and an upper magnetic pole layer 18. The lower magnetic pole layer 10 has a magnetic pole partial layer 10a and a yoke partial layer 10b. The magnetic pole partial layer 10a includes a first part 10a<SB>1</SB>and a second part 10a<SB>2</SB>with a width larger than that of the first part 10a<SB>1</SB>. The width of a portion of the recording gap layer 17 side in the first part 10a<SB>1</SB>is smaller than the width of the other parts of the first part 10a<SB>1</SB>and is equal to that of a recording track. An insulation layer is arranged at both sides in the track width direction of the first part 10a<SB>1</SB>, and a surface of the other parts on the recording gap layer 17 side in the first part 10a<SB>1</SB>and a surface of the insulation layer on the recording gap layer 17 side are formed flat. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thin-film magnetic head having at least an inductive electromagnetic transducer and a method for manufacturing the same.

  In recent years, as the areal recording density of a hard disk device has been improved, the performance of a thin-film magnetic head has been required to be improved. As the thin-film magnetic head, a composite type having a structure in which a recording head having an inductive electromagnetic transducer for writing and a reproducing head having a magnetoresistive (hereinafter also referred to as MR (Magneto-resistive)) element for reading are stacked. Thin film magnetic heads are widely used.

  Incidentally, in order to increase the recording density of the performance of the recording head, it is necessary to increase the track density in the magnetic recording medium. For this purpose, it is necessary to realize a recording head having a narrow track structure in which the width of the lower magnetic pole and the upper magnetic pole formed above and below the recording gap layer on the air bearing surface is reduced from several microns to submicron dimensions. Yes, semiconductor processing technology is used to achieve this.

  Here, an example of a method of manufacturing a composite thin-film magnetic head will be described as an example of a conventional method of manufacturing a thin-film magnetic head with reference to FIGS. In FIGS. 9 to 12, (a) shows a cross section perpendicular to the air bearing surface, and (b) shows a cross section of the magnetic pole portion parallel to the air bearing surface.

In this manufacturing method, first, as shown in FIG. 9, an insulating layer 102 made of, for example, alumina (Al ₂ O ₃ ) is formed on a substrate 101 made of, for example, Altic (Al ₂ O ₃ .TiC). It is deposited with a thickness of about 5 to 10 μm. Next, a lower shield layer 103 for a read head made of a magnetic material is formed on the insulating layer 102.

  Next, on the lower shield layer 103, for example, alumina is sputter deposited to a thickness of 100 to 200 nm to form a lower shield gap film 104 as an insulating layer. Next, on the lower shield gap film 104, a reproducing MR element 105 is formed with a thickness of several tens nm. Next, a pair of electrode layers 106 that are electrically connected to the MR element 105 are formed on the lower shield gap film 104.

  Next, an upper shield gap film 107 as an insulating layer is formed on the lower shield gap film 104 and the MR element 105, and the MR element 105 is embedded in the shield gap films 104 and 107.

  Next, on the upper shield gap film 107, an upper shield layer and a lower magnetic pole layer (hereinafter, referred to as a lower magnetic pole layer) 108 made of a magnetic material and used for both the read head and the write head is about 3 μm. It is formed to a thickness.

  Next, as shown in FIG. 10, a recording gap layer 109 made of an insulating film, for example, an alumina film is formed on the lower magnetic pole layer 108 to a thickness of 0.2 μm. Next, in order to form a magnetic path, the recording gap layer 109 is partially etched to form a contact hole 109a. Next, an upper pole tip 110 made of a magnetic material for a recording head is formed to a thickness of 0.5 to 1.0 μm on the recording gap layer 109 at the pole portion. At the same time, a magnetic layer 119 made of a magnetic material for forming a magnetic path is formed on the contact hole 109a for forming a magnetic path.

  Next, as shown in FIG. 11, using the upper pole tip 110 as a mask, the recording gap layer 109 and the lower pole layer 108 are etched by ion milling. As shown in FIG. 11B, the structure in which the side walls of the upper magnetic pole portion (upper magnetic pole tip 110), the write gap layer 109, and a part of the lower magnetic pole layer 108 are formed in a self-aligned vertical manner is trimmed. (Trim) structure.

  Next, an insulating layer 111 made of, for example, an alumina film is formed on the entire surface to a thickness of about 3 μm. Next, the insulating layer 111 is polished and flattened to the surface of the upper magnetic pole tip 110 and the magnetic layer 119.

  Next, on the planarized insulating layer 111, a first-layer thin-film coil 112 made of, for example, copper (Cu) for an inductive recording head is formed. Next, a photoresist layer 113 is formed on the insulating layer 111 and the coil 112 in a predetermined pattern. Next, heat treatment is performed at a predetermined temperature to planarize the surface of the photoresist layer 113. Next, a second-layer thin-film coil 114 is formed on the photoresist layer 113. Next, a photoresist layer 115 is formed in a predetermined pattern on the photoresist layer 113 and the coil 114. Next, heat treatment is performed at a predetermined temperature to planarize the surface of the photoresist layer 115.

  Next, as shown in FIG. 12, an upper magnetic pole layer 116 made of a magnetic material for a recording head, for example, permalloy is formed on the upper magnetic pole tip 110, the photoresist layers 113 and 115, and the magnetic layer 119. Next, an overcoat layer 117 made of, for example, alumina is formed on the upper magnetic pole layer 116. Finally, the slider including the above layers is machined to form the air bearing surface 118 of the thin film magnetic head including the recording head and the reproducing head, thereby completing the thin film magnetic head.

  FIG. 13 is a plan view of the thin-film magnetic head shown in FIG. Note that, in this drawing, the overcoat layer 117, other insulating layers and insulating films are omitted.

  In FIG. 12A, TH indicates the throat height, and MR-H indicates the MR height. The throat height refers to the length (height) from the end on the air bearing surface side to the end on the opposite side of the portion where the two magnetic pole layers face each other via the recording gap layer. The MR height refers to the length (height) from the end on the air bearing surface side of the MR element to the end on the opposite side. In FIG. 12B, P2W represents the magnetic pole width, that is, the recording track width. As a factor that determines the performance of the thin-film magnetic head, there is an Apex Angle as indicated by θ in FIG. 12A, in addition to the throat height and the MR height. The apex angle is a top surface of the insulating layer 111 and a straight line connecting a corner of a side surface on a magnetic pole side in a coil portion (hereinafter, referred to as an apex portion) which is covered with the photoresist layers 113 and 115 and is raised in a mountain shape. With the angle.

  In order to improve the performance of the thin-film magnetic head, it is important to accurately form the throat height TH, MR height MR-H, apex angle θ, and recording track width P2W as shown in FIG.

  In particular, in recent years, in order to enable high areal density recording, that is, to form a recording head having a narrow track structure, a submicron dimension of 1.0 μm or less is required for the track width P2W. For this purpose, a technique for processing the upper magnetic pole into a submicron size using a semiconductor processing technique is required.

  Here, the problem is that it is difficult to finely form the upper magnetic pole layer formed on the apex portion.

  By the way, as a method for forming the upper magnetic pole layer, for example, a frame plating method is used as shown in Patent Document 1. When the upper magnetic pole layer is formed by using the frame plating method, first, a thin electrode film made of, for example, permalloy is entirely formed on the apex portion by, for example, sputtering. Next, a photoresist is applied thereon and patterned by a photolithography process to form a frame (outer frame) for plating. Then, the upper magnetic pole layer is formed by plating using the previously formed electrode film as a seed layer.

  However, there is a height difference of, for example, 7 to 10 μm or more between the apex portion and other portions. On this apex portion, a photoresist is applied in a thickness of 3 to 4 μm. If the thickness of the photoresist on the apex portion is required to be at least 3 μm or more, the photoresist having fluidity is gathered on the lower side, so that the photoresist having a thickness of, for example, 8 to 10 μm or more is provided below the apex portion. A resist film is formed.

  To realize a recording track width of a submicron size as described above, it is necessary to form a frame pattern having a submicron width by a photoresist film. Therefore, a submicron-sized fine pattern must be formed on the apex portion by a photoresist film having a thickness of 8 to 10 μm or more. However, it is extremely difficult in the manufacturing process to form such a thick photoresist pattern with a narrow pattern width.

  In addition, at the time of photolithographic exposure, light for exposure is reflected by the base electrode film as a seed layer, and the photoresist is also exposed to the reflected light, causing the photoresist pattern to be distorted and the like to be sharp and accurate. A photoresist pattern cannot be obtained.

  As described above, conventionally, when the magnetic pole width has a submicron size, there has been a problem that it is difficult to form the upper magnetic layer with high accuracy.

  For this reason, the track width of 1.0 μm or less was formed by the upper magnetic pole chip 110 effective for forming the narrow track of the recording head as shown in the steps of FIGS. Thereafter, a method of forming an upper magnetic pole layer 116 serving as a yoke portion connected to the upper magnetic pole chip 110 is also adopted (see Patent Documents 2 and 3). As described above, by dividing the normal upper magnetic pole layer into the upper magnetic pole chip 110 and the upper magnetic pole layer 116 serving as a yoke portion, the upper magnetic pole chip 110 for determining the recording track width can be formed on the recording gap layer 109. On a flat surface, it can be formed to some extent fine.

  Patent Document 4 discloses a thin-film magnetic head in which both an upper magnetic pole layer and a lower magnetic pole layer are composed of two layers, a layer including a magnetic pole portion and a layer serving as a yoke portion.

JP-A-7-262519 JP-A-62-245509 JP-A-60-10409 JP-A-6-314413

  However, in both the thin-film magnetic head shown in FIG. 12 and the thin-film magnetic head disclosed in Patent Document 4, the end surface of the layer serving as the yoke portion is exposed to the air bearing surface. Therefore, in such a thin-film magnetic head, writing is performed not only on the layer including the magnetic pole portion but also on the layer side serving as the yoke portion, and the data is written to the recording medium in an area other than the area to be originally recorded. There is a problem that writing, so-called side light, occurs.

  Further, in the thin-film magnetic head disclosed in Patent Document 4, in the magnetic pole portion, a total of four layers, that is, two upper magnetic pole layers and two lower magnetic pole layers, are formed to have the same width. As a method of forming the four layers so that the widths of the magnetic pole portions are equal, a method of forming each layer so that the shape of the magnetic pole portion of each layer is determined at the time of forming each layer, or a method of forming four layers Later, a method is considered in which the four layers are collectively etched so that the widths of the four layers in the magnetic pole portion become equal.

  However, in the method of forming each layer so that the shape of the magnetic pole portion of each layer is determined at the time of forming each layer, particularly when the recording track width is reduced, the shape of the magnetic pole portion of each layer is accurately determined, In addition, there is a problem that it is difficult to accurately position the magnetic pole portions of each layer.

  In addition, the method of simultaneously etching the four layers has a problem that it takes a lot of time for the etching and it is difficult to accurately determine the shape of the magnetic pole portion of the four layers.

  Further, the conventional thin-film magnetic head has a problem that it is difficult to shorten the magnetic path length (Yoke Length). That is, as the coil pitch becomes smaller, a head having a shorter magnetic path length can be realized. In particular, a recording head having excellent high-frequency characteristics can be formed. The distance from the zero height position (the position of the end of the insulating layer on the air bearing surface side that determines the throat height) to the outer peripheral end of the coil has been a major factor that prevents shortening the magnetic path length. Since the magnetic path length of a two-layer coil can be shorter than that of a single-layer coil, many high-frequency recording heads employ a two-layer coil. However, in a conventional magnetic head, a photoresist film is formed to a thickness of about 2 μm in order to form an insulating film between the coils after the first-layer coil is formed. Therefore, a small rounded apex portion is formed at the outer peripheral end of the coil of the first layer. Next, a second-layer coil is formed thereon. At this time, since the seed layer of the coil cannot be etched at the inclined portion of the apex portion and the coil is short-circuited, the second-layer coil is formed. It must be formed on a flat part.

  Therefore, for example, when the thickness of the coil is 2 to 3 μm, the thickness of the inter-coil insulating film is 2 μm, and the apex angle is 45 ° to 55 °, the magnetic path length is the length of the portion corresponding to the coil. In addition, the distance from the outer peripheral end of the coil to the vicinity of the throat height zero position is twice the distance of 3 to 4 μm (the distance from the contact portion between the upper magnetic pole layer and the lower magnetic pole layer to the inner peripheral end of the coil is also 3 to 4 μm). Required) of 6 to 8 μm. The length other than the portion corresponding to the coil has been a factor that hinders the reduction of the magnetic path length.

Here, for example, consider a case where an eleven-turn coil having a coil line width of 1.2 μm and a space of 0.8 μm is formed in two layers. In this case, as shown in FIG. 12, when the first layer has six windings and the second layer has five windings, the length corresponding to the coil 112 of the first layer in the magnetic path length is 11.2 μm. It is. In addition to the magnetic path length, the distance from the outer peripheral end and the inner peripheral end of the first-layer coil 112 to the end of the photoresist layer 113 for insulating the first-layer coil 112 is 6 in total. A length of ８8 μm is required. Therefore, the magnetic path length is 17.2-19.2 μm. If the 11-turn coil is formed by one layer, the magnetic path length is 27.2 to 29.2 μm. In the present application, the magnetic path length is represented by the length of the magnetic pole layer excluding the magnetic pole portion and the contact portion, as indicated by reference numeral L ₀ in FIG. As described above, conventionally, it has been difficult to reduce the magnetic path length, which has hindered the improvement of high frequency characteristics.

  The present invention has been made in view of such a problem, and a first object of the present invention is to form a magnetic pole portion of an inductive electromagnetic transducer with high accuracy and to transfer data to an area other than an area to be recorded. An object of the present invention is to provide a thin-film magnetic head capable of preventing writing and a method of manufacturing the same.

  A second object of the present invention is to provide a thin-film magnetic head capable of reducing a magnetic path length and a method of manufacturing the same in addition to the first object.

The thin-film magnetic head of the present invention
A first and a second magnetic layer magnetically coupled to each other, the first and second magnetic layers each including at least one layer, the first and second magnetic layers including magnetic pole portions magnetically coupled to each other and facing each other on the medium facing surface side; A gap layer provided between the magnetic pole portion of the magnetic layer and the magnetic pole portion of the second magnetic layer, at least a portion between the first and second magnetic layers, and a gap layer between the first and second magnetic layers; A thin-film magnetic head comprising a thin-film coil provided in a state insulated from the thin-film coil,
The first magnetic layer has a first portion having one end located on the medium facing surface, and a first portion located on the side opposite to the medium facing surface with respect to the first portion, and having a width larger than the width of the first portion. And a second part having
The second magnetic layer has a portion having one end disposed on the medium facing surface and having a width equal to the track width;
The thin-film magnetic head further includes an insulating layer disposed on both sides of the first portion in the track width direction,
The width of a part of the first part on the gap layer side is smaller than the width of the other part of the first part and equal to the track width;
The surface of the other portion of the first portion on the gap layer side and the surface of the insulating layer on the gap layer side form a flat surface.

The method for manufacturing a thin-film magnetic head of the present invention comprises:
Forming a first magnetic layer;
Forming a gap layer on the first magnetic layer;
Forming a second magnetic layer on the gap layer;
Forming a thin-film coil between at least a part of the first and second magnetic layers so as to be disposed insulated from the first and second magnetic layers;
The first magnetic layer has a first portion having one end located on the medium facing surface, and a first portion located on the side opposite to the medium facing surface with respect to the first portion, and having a width larger than the width of the first portion. And a second part having
The second magnetic layer has a portion having one end disposed on the medium facing surface and having a width equal to the track width.

The method for manufacturing a thin-film magnetic head of the present invention further comprises:
Forming an insulating layer disposed on both sides of the first portion in the track width direction;
After the formation of the second magnetic layer, the width of a part of the first part on the gap layer side is smaller than the width of the other part of the first part and equal to the track width, and Etching a part of the first part and a part of the insulating layer such that a surface of the other part on the gap layer side and a surface of the insulating layer on the gap layer side form a flat surface. .

  In the thin film magnetic head or the method of manufacturing the same according to the present invention, the first magnetic layer has a first surface adjacent to the gap layer, the first magnetic layer includes a first portion and a second portion, and the first magnetic layer includes a first portion and a second portion. And a yoke portion layer connected to the other surface and serving as a yoke portion in the first magnetic layer. In this case, at least a part of the thin-film coil may be arranged on the side of the pole part layer. Further, the end of the yoke partial layer on the medium facing surface side may be arranged at a position away from the medium facing surface.

  In the thin-film magnetic head or the method of manufacturing the same according to the present invention, the first magnetic layer has a first portion having one end disposed on the medium facing surface and a first portion disposed on a side opposite to the medium facing surface with respect to the first portion. , A second portion having a width greater than the width of the first portion, and the second magnetic layer has a portion having one end disposed on the medium facing surface and having a width equal to the track width. . Insulating layers are disposed on both sides of the first portion in the track width direction, and the width of a portion of the first portion on the gap layer side is smaller than the width of the other portion of the first portion and the width of the track is smaller. The width is equal to the width, and the surface of the other portion of the first portion on the gap layer side and the surface of the insulating layer on the gap layer side form a flat surface. Thus, according to the present invention, the width of a portion of the second magnetic layer having a width equal to the track width and the width of a portion of the first portion of the first magnetic layer on the gap layer side are changed. Equalization to the width can be easily and accurately performed. Therefore, according to the present invention, it is possible to form the magnetic pole portion of the inductive electromagnetic transducer with high accuracy. Further, according to the present invention, it is possible to prevent the spread of the magnetic flux on the medium facing surface, and as a result, it is possible to prevent the writing of data to an area other than the area to be recorded.

  Further, in the thin film magnetic head or the method of manufacturing the same according to the present invention, the first magnetic layer has a pole portion layer and a yoke portion layer, and at least a part of the thin film coil is arranged on a side of the pole portion layer. In this case, there is an effect that the magnetic path length can be reduced.

  In the thin-film magnetic head or the method of manufacturing the same according to the present invention, the first magnetic layer has a pole portion layer and a yoke portion layer, and the end of the yoke portion layer on the medium facing surface side is separated from the medium facing surface. When they are arranged at positions, it is possible to prevent data from being written into an area other than the area to be recorded.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
First, a thin-film magnetic head and a method of manufacturing the same according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 6, (a) shows a cross section perpendicular to the air bearing surface, and (b) shows a cross section of a magnetic pole portion parallel to the air bearing surface.

In the method of manufacturing a thin film magnetic head of the embodiment, first, as shown in FIG. 1, for example on the AlTiC (Al ₂ O ₃ · TiC) than consisting substrate 1, alumina (Al ₂ O ₃ ) Is deposited to a thickness of about 5 μm. Next, a lower shield layer 3 for a reproducing head made of a magnetic material, for example, permalloy is formed on the insulating layer 2 to a thickness of about 3 μm. The lower shield layer 3 is selectively formed on the insulating layer 2 by, for example, plating using a photoresist film as a mask. Next, an insulating layer 31 made of, for example, alumina is formed on the whole to a thickness of, for example, 4 to 5 μm, and polished by, for example, chemical mechanical polishing (hereinafter, referred to as CMP) until the lower shield layer 3 is exposed. Then, the surface is flattened.

Next, a lower shield gap film 4 as an insulating film is formed on the lower shield layer 3 to a thickness of, for example, about 20 to 40 nm. Next, an MR element 5 for reproduction is formed on the lower shield gap film 4 to a thickness of several tens nm. The MR element 5 is formed, for example, by selectively etching an MR film formed by sputtering. Note that, as the MR element 5, an element using a magneto-sensitive film exhibiting a magnetoresistance effect, such as an AMR element, a GMR element, or a TMR (tunnel magnetoresistance effect) element can be used. Next, a pair of electrode layers 6 electrically connected to the MR element 5 is formed on the lower shield gap film 4 to a thickness of several tens nm. Next, an upper shield gap film 7 as an insulating film is formed on the lower shield gap film 4 and the MR element 5 to a thickness of, for example, about 20 to 40 nm, and the MR element 5 is formed in the shield gap films 4 and 7. Buried. Examples of the insulating material used for the shield gap films 4 and 7 include alumina, aluminum nitride, and diamond-like carbon (DLC). Further, the shield gap films 4 and 7 may be formed by a sputtering method or may be formed by a chemical vapor deposition (CVD) method. When the shield gap films 4 and 7 made of an alumina film are formed by a CVD method, for example, trimethyl aluminum (Al (CH ₃ ) ₃ ) and H ₂ O are used as materials. When the CVD method is used, it is possible to form thin, dense, shield gap films 4 and 7 with few pinholes.

  Next, on the upper shield gap film 7, an upper shield layer 8 for a reproducing head, made of a magnetic material, for example, permalloy, is selectively formed with a thickness of, for example, 1.0 μm. Next, an insulating layer 32 made of, for example, alumina is formed to a thickness of about 2 to 3 μm on the whole, and polished by, for example, CMP until the upper shield layer 8 is exposed, and the surface is flattened.

  Next, on the upper shield layer 8 and the insulating layer 32, an insulating film 9 made of, for example, alumina for magnetically insulating the read head from the recording head is formed to a thickness of, for example, 0.1 to 0.2 μm. Form.

  Next, as shown in FIG. 2, a yoke portion layer 10b serving as a yoke portion of the lower magnetic pole layer 10 for a recording head is formed on the insulating film 9 by a magnetic material to a thickness of, for example, 1.0 to 1.5 μm. It is selectively formed with a thickness. The lower magnetic pole layer 10 includes the yoke partial layer 10b, and a magnetic pole partial layer 10a and a connecting partial layer 10c described later. The end of the yoke portion layer 10b on the air bearing surface 30 side is arranged at a position away from the air bearing surface 30.

  The yoke partial layer 10b is formed by plating using NiFe (Ni: 80% by weight, Fe: 20% by weight), NiFe (Ni: 45% by weight, Fe: 55% by weight) which is a high saturation magnetic flux density material, or the like. It may be formed, or may be formed by sputtering using a material such as FeN or FeZrN which is a high saturation magnetic flux density material. In addition, a high saturation magnetic flux density material such as CoFe or a Co-based amorphous material may be used.

  Next, an insulating layer made of, for example, alumina is formed on the whole to a thickness of about 2 to 3 μm, and polished by, for example, CMP until the yoke partial layer 10b is exposed, and the surface is flattened. Thereby, as shown in FIG. 2, the insulating layer 11 is formed on the insulating film 9 in the portion from the end on the air bearing surface 30 side of the yoke portion layer 10 b to the air bearing surface 30.

  Next, as shown in FIG. 3, the pole portion layer 10a of the lower pole layer 10 is formed on the insulating layer 11 and the yoke portion layer 10b, and the connection portion layer 10c is formed on the yoke portion layer 10b. . The pole portion layer 10a includes a pole portion in the lower pole layer 10. The connection portion layer 10c is disposed at a position near the center of a thin-film coil described later. The thickness of the pole portion layer 10a and the connection portion layer 10c is, for example, 1.0 to 1.5 μm.

  The magnetic pole portion layer 10a and the connection portion layer 10c of the lower magnetic pole layer 10 are made of NiFe (Ni: 80% by weight, Fe: 20% by weight) or NiFe (Ni: 45% by weight, Fe: 55) which is a high saturation magnetic flux density material. Weight%) or the like, and may be formed by sputtering using a material such as FeN or FeZrN which is a high saturation magnetic flux density material. In addition, a high saturation magnetic flux density material such as CoFe or a Co-based amorphous material may be used.

  Next, as shown in FIG. 4, an insulating film 12 made of, for example, alumina is formed to a thickness of about 0.3 to 0.5 [mu] m. Next, a thin film coil 13 made of, for example, copper is formed on the insulating film 12 by frame plating, for example, to a thickness of 0.8 to 1.0 μm. The thin film coil 13 is formed so as to be wound around the connection partial layer 10c. In the drawing, reference numeral 13a indicates a connection portion for connecting the thin-film coil 13 to a lead layer 19 described later. Next, a photoresist layer 14 is formed so as to surround the thin film coil 13.

  Next, a coil insulating layer 15 made of, for example, alumina is formed with a thickness of about 3 to 4 μm on the whole. Next, the coil insulating layer 15 is polished by, for example, CMP until the magnetic pole portion layer 10a and the connection portion layer 10c of the lower magnetic pole layer 10 are exposed, and the surface is flattened. Here, although the thin film coil 13 is not exposed in FIG. 4, the thin film coil 13 may be exposed. As shown in FIG. 4B, the coil insulating layers 15 are also arranged on both sides of the pole portion layer 10a in the track width direction.

  Next, as shown in FIG. 5, on the whole except a portion from a position separated by a predetermined distance from the air bearing surface 30 to the air bearing surface 30, it is made of, for example, alumina for defining a throat height. The insulating layer 16 is formed to a thickness of, for example, 0.8 μm.

Next, a recording gap layer 17 made of an insulating material is entirely formed to a thickness of, for example, 0.1 to 0.15 μm. Generally, the insulating material used for the recording gap layer 17 includes alumina, aluminum nitride, silicon oxide-based material, silicon nitride-based material, diamond-like carbon (DLC), and the like. Further, the recording gap layer 17 may be formed by a sputtering method or a chemical vapor deposition (CVD) method. When the recording gap layer 17 made of an alumina film is formed by a CVD method, for example, trimethyl aluminum (Al (CH ₃ ) ₃ ) and H ₂ O are used as materials. The use of the CVD method makes it possible to form a thin, dense recording gap layer 17 with few pinholes.

  Next, a contact hole is formed by partially etching the recording gap layer 17 and the insulating layer 16 in the portion above the connection portion layer 10c of the lower magnetic pole layer 10 and the portion above the connection portion 13a of the thin film coil 13. .

  Next, as shown in FIG. 6, on the recording gap layer 17, from the air bearing surface 30 to the portion above the connection portion layer 10c of the lower pole layer 10, the upper pole layer 18 is, for example, 2.0-3. The lead layer 19 is formed to have a thickness of, for example, 3 to 4 μm so as to be connected to the connection portion 13 a of the thin film coil 13. The upper magnetic pole layer 18 is connected to the connection partial layer 10c of the lower magnetic pole layer 10.

  The upper magnetic pole layer 18 is formed by plating using NiFe (Ni: 80% by weight, Fe: 20% by weight), NiFe (Ni: 45% by weight, Fe: 55% by weight) which is a high saturation magnetic flux density material, or the like. It may be formed, or may be formed by sputtering using a material such as FeN or FeZrN which is a high saturation magnetic flux density material. In addition, a high saturation magnetic flux density material such as CoFe or a Co-based amorphous material may be used. Further, in order to improve high-frequency characteristics, the upper magnetic pole layer 18 may have a structure in which an inorganic insulating film and a magnetic layer such as permalloy are superposed in any number of layers.

Next, around the magnetic pole portion of the upper magnetic pole layer 18, the recording gap layer 17 is selectively etched by dry etching using the upper magnetic pole layer 18 as a mask. The dry etching at this time is, for example, reactive ion etching (hereinafter referred to as RIE) using a gas such as a chlorine-based gas such as BCl ₂ or Cl ₂ or a fluorine-based gas such as CF ₄ or SF ₆ . Is used. Next, around the magnetic pole portion of the upper magnetic pole layer 18, a part of the magnetic pole partial layer 10 a of the lower magnetic pole layer 10 and the insulating layer 15 are formed using the upper magnetic pole layer 18 as a mask, for example, by ion milling using an argon-based gas. A portion is selectively etched by about 0.3 to 0.6 μm to obtain a trim structure as shown in FIG. As a result, around the magnetic pole portion of the upper magnetic pole layer 18, the width of a part of the magnetic pole partial layer 10a on the recording gap layer 17 side is smaller than the width of the other portion of the magnetic pole partial layer 10a and equal to the recording track width. Become. The other surface of the pole portion layer 10a on the recording gap layer 17 side and the surface of the coil insulating layer 15 on the recording gap layer 17 side form a flat surface. According to this trim structure, it is possible to prevent an increase in the effective track width due to the spread of the magnetic flux generated on the air bearing surface 30 at the time of writing a narrow track. As a result, writing data to an area other than the area to be recorded Can be prevented.

  Next, an overcoat layer 20 made of, for example, alumina is entirely formed to a thickness of, for example, 20 to 40 μm, the surface thereof is flattened, and an electrode pad (not shown) is formed thereon. Finally, the slider including the above layers is polished to form the air bearing surface 30 of the thin film magnetic head including the recording head and the reproducing head, and the thin film magnetic head according to the present embodiment is completed.

  FIG. 7 is a perspective view showing the vicinity of the magnetic pole portions of the lower magnetic pole layer 10 and the upper magnetic pole layer 18 in the thin-film magnetic head according to the present embodiment.

  In the present embodiment, the lower magnetic pole layer 10 corresponds to the first magnetic layer in the present invention, and the upper magnetic pole layer 18 corresponds to the second magnetic layer in the present invention.

  As described above, the thin-film magnetic head according to the present embodiment includes the medium facing surface (air bearing surface 30) facing the recording medium, the reproducing head, and the recording head (inductive electromagnetic transducer). I have. The reproducing head and the recording head are magnetically insulated by the insulating film 9.

  The reproducing head has an MR element 5, a lower shield layer 3 and an upper shield layer 8 which are arranged so that a part of the air bearing surface 30 is opposed to the MR element 5 with the MR element 5 interposed therebetween. ing.

  The write head includes magnetic pole portions magnetically coupled to each other and includes magnetic pole portions facing each other on the air bearing surface 30 side, and includes a lower magnetic pole layer 10 and an upper magnetic pole layer 18 each including at least one layer. And a recording gap layer 17 provided between the magnetic pole portions 18 and at least a portion thereof is disposed between the two magnetic pole layers 10 and 18 while being insulated from the two magnetic pole layers 10 and 18. And the thin film coil 13 formed.

  The lower magnetic pole layer 10 has one surface (upper surface) adjacent to the recording gap layer 17 and is connected to the magnetic pole portion layer 10a including the magnetic pole portion of the lower magnetic pole layer 10 and the other surface (lower surface) of the magnetic pole portion layer 10a. And a yoke portion layer 10b serving as a yoke portion in the lower magnetic pole layer 10. The end of the yoke portion layer 10b on the air bearing surface 30 side is arranged at a position away from the air bearing surface 30. The insulating layer 11 is disposed in a portion from the end on the air bearing surface 30 side of the yoke portion layer 10b to the air bearing surface 30. The upper magnetic pole layer 18 is a single layer having a portion that defines a track width.

Further, as shown in FIG. 7, the magnetic pole portion layer 10a in the lower magnetic pole layer 10 has one end disposed on the air bearing surface 30, a first portion 10a ₁ having a width at least a part is equal to the recording track width , the air bearing surface 30 than the first portion 10a ₁ located opposite, and a second portion 10a ₂ having a width greater than the recording track width. Portion of the width of the recording gap layer 17 side of the first portion 10a ₁ is equal to the small and the recording track width than the other portion of the first portion 10a _1. Moreover, as can be seen from FIG. 6 (b), on both sides of the first portion 10a ₁ in the track width direction, the coil insulating layer 15 is disposed. Then, the surface of the recording gap layer 17 side of the recording gap layer 17 side surface and the coil insulating layer 15 in other parts of the of the first portion 10a ₁ forms a flat surface.

  The upper magnetic pole layer 18 has a first portion 18A, a second portion 18B, and a third portion 18C arranged in order from the air bearing surface 30 side. The width of the first portion 18A is equal to the recording track width, the width of the second portion 18B is greater than the width of the first portion 18A, and the width of the third portion 18C is greater than the width of the second portion 18B. It is getting bigger. The width of the third portion 18C gradually decreases as approaching the air bearing surface 30.

  Further, the thin-film coil 13 is arranged on the side of the pole portion layer 10a of the lower pole layer 10. The thin-film coil 13 is covered with a photoresist layer 14 and a coil insulating layer 15, and the upper surface of the coil insulating layer 15 is flattened together with the upper surface of the pole portion layer 10a.

  As described above, in the present embodiment, the lower magnetic pole layer 10 has the magnetic pole partial layer 10a and the yoke partial layer 10b. Therefore, according to the present embodiment, the pole portion layer 10a including the pole portion can be formed minutely and accurately. In the present embodiment, the thin-film coil 13 is arranged on the side of the pole portion layer 10a of the lower pole layer 10, and the upper surface of the coil insulating layer 15 covering the thin-film coil 13 is placed on the pole portion layer 10a of the lower pole layer 10. The upper magnetic pole layer 18 is formed on the flattened surface via the insulating layer 16 and the recording gap layer 17. Therefore, according to the present embodiment, the upper magnetic pole layer 18 made of one layer can be formed in a flat or nearly flat state, and as a result, the upper magnetic pole layer 18 including the magnetic pole portion can be formed finely and accurately. It becomes possible to do.

  Further, in the present embodiment, the end of the yoke portion layer 10 b of the lower magnetic pole layer 10 on the air bearing surface 30 side is arranged at a position away from the air bearing surface 30. Therefore, in the present embodiment, when the width of the magnetic pole portion of the upper magnetic pole layer 18 on the air bearing surface 30 is made equal to the width of the magnetic pole portion of the lower magnetic pole layer 10, the magnetic pole portion layer 10a of the upper magnetic pole layer 18 and the lower magnetic pole layer is formed. The widths of the magnetic pole portions need to be equal only for the two layers of the upper magnetic pole layer 18 and the magnetic pole partial layer 10a, not for the three layers of the yoke partial layer 10b. Therefore, according to the present embodiment, the width of the magnetic pole portion of upper magnetic pole layer 18 and the width of the magnetic pole portion of lower magnetic pole layer 10 can be easily and accurately made.

  As described above, according to the present embodiment, it is possible to accurately form the magnetic pole portion of the recording head (the induction type electromagnetic transducer).

  Further, according to the present embodiment, the end of the yoke portion layer 10b on the air bearing surface 30 side is arranged at a position distant from the air bearing surface 30, so that data can be written to an area other than the area to be recorded. That is, side light can be prevented.

  By the way, conventionally, in a composite type thin film magnetic head having a structure in which a lower magnetic pole layer of a recording head also serves as an upper shield layer of a reproducing head, noise is generated in a reproducing signal of the reproducing head immediately after a recording operation of the recording head, There is a problem that the fluctuation of the reproduction signal becomes large. One of the causes is considered to be residual magnetism generated on the recording head side due to the recording operation of the recording head and its fluctuation.

  On the other hand, in the present embodiment, the upper shield layer 8 of the reproducing head and the lower magnetic pole layer 10 of the recording head are separated, and the insulating film 9 is disposed between them. As a result, the influence of the residual magnetism generated on the recording head side on the MR element 5 can be reduced. Further, in the present embodiment, the end of the yoke portion layer 10b of the lower magnetic pole layer 10 on the air bearing surface 30 side is arranged at a position away from the air bearing surface 30, and the yoke portion layer 10b on the air bearing surface 30 side is located on the air bearing surface 30 side. Since the insulating layer 11 is arranged in a portion from the end to the air bearing surface 30, the magnetic pole portion of the recording head and the MR element 5 of the reproducing head can be magnetically separated by the insulating layer 11. As a result, according to the present embodiment, the effect of the residual magnetism generated on the recording head side on the MR element 5 can be further reduced by the insulating layer 11. Therefore, according to the present embodiment, it is possible to reduce noise and fluctuation generated in a reproduction signal of the reproduction head due to the recording operation of the recording head.

  In the present embodiment, the thin-film coil 13 is arranged on the side of the pole portion layer 10 a of the lower pole layer 10 and is formed on the flat insulating film 12. Therefore, according to the present embodiment, it is possible to form the thin-film coil 13 finely and accurately. Further, according to the present embodiment, the end of thin-film coil 13 can be arranged near the end of pole portion layer 10a opposite to air bearing surface 30. From these facts, according to the present embodiment, it is possible to reduce the magnetic path length as compared with the related art. Further, the magnetomotive force generated by the thin film coil 13 can be prevented from being saturated on the way, and the magnetomotive force generated by the thin film coil 13 can be efficiently used for recording. Therefore, according to the present embodiment, there is provided a thin-film magnetic head having excellent high-frequency characteristics of a recording head, a non-linear transition shift (NLTS), and an overwrite characteristic which is a characteristic for overwriting. It is possible to do.

  Further, in the present embodiment, the thin film coil 13 is arranged on the side of the magnetic pole portion layer 10a of the lower magnetic pole layer 10, and the upper surface of the coil insulating layer 15 covering the thin film coil 13 is flattened together with the upper surface of the magnetic pole portion layer 10a. ing. Therefore, according to the present embodiment, it is possible to accurately form a layer adjacent to coil insulating layer 15.

  Further, in the present embodiment, since the thin-film coil 13 is arranged on the side of the magnetic pole portion layer 10a of the lower magnetic pole layer 10, the upper magnetic pole layer 18 can be constituted by one substantially flat layer. Therefore, according to the present embodiment, the number of steps can be reduced as compared with the case where the upper pole layer is composed of a plurality of layers.

[Second embodiment]
Next, a thin-film magnetic head and a method of manufacturing the same according to a second embodiment of the present invention will be described with reference to FIG. 8A and 8B show the configuration of the thin-film magnetic head according to the present embodiment. FIG. 8A shows a cross section perpendicular to the air bearing surface, and FIG. 8B shows a cross section of the magnetic pole portion parallel to the air bearing surface.

  In the present embodiment, as shown in FIG. 8B, the width of the upper magnetic pole layer 18 on the air bearing surface 30 and the width of the magnetic pole portion layer 10a are made equal throughout the thickness direction. In order to equalize the widths of the two, the recording gap layer 17 and the pole portion layer 10a may be etched using the upper pole layer 18 as a mask, or a mask layer formed on the upper pole layer 18 may be used. As a mask, a method of etching the upper magnetic pole layer 18, the recording gap layer 17, and the magnetic pole partial layer 10a may be used. As an etching method, for example, RIE is used. The mask layer is formed, for example, by forming a patterned metal layer on the alumina layer, and etching the alumina layer by RIE using the metal layer as a mask.

  In the present embodiment, the upper magnetic pole layer 18, the recording gap layer 17, and the magnetic pole partial layer 10a of the lower magnetic pole layer 10 may be etched by a focused ion beam.

  Other configurations, operations, and effects of the present embodiment are the same as those of the first embodiment.

  The present invention is not limited to the above embodiments, and various modifications are possible. For example, in each of the above embodiments, a thin film magnetic head having a structure in which an MR element for reading is formed on the substrate side and an inductive electromagnetic transducer for writing is stacked thereon has been described. It may be.

  That is, an inductive electromagnetic transducer for writing may be formed on the substrate side, and an MR element for reading may be formed thereon. In such a structure, for example, the magnetic film having the function of the upper magnetic pole layer shown in the above-described embodiment is formed on the substrate side as the lower magnetic pole layer, and the magnetic film having the above-mentioned structure is opposed to the magnetic pole layer via the recording gap film. This can be realized by forming the magnetic film having the function of the lower magnetic pole layer shown in the embodiment as the upper magnetic pole layer.

  In addition, the present invention can be applied to a thin-film magnetic head dedicated to recording including only an inductive electromagnetic transducer, and a thin-film magnetic head that performs recording and reproduction using an inductive electromagnetic transducer.

FIG. 5 is a cross-sectional view for explaining one step in the method of manufacturing the thin-film magnetic head according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view for explaining a step following the step shown in FIG. 1. FIG. 3 is a cross-sectional view for explaining a step following the step shown in FIG. 2. FIG. 4 is a cross-sectional view for explaining a step following the step shown in FIG. 3. FIG. 5 is a cross-sectional view for explaining a step following the step shown in FIG. 4. FIG. 2 is a sectional view of the thin-film magnetic head according to the first embodiment of the present invention. FIG. 3 is a perspective view showing the vicinity of the magnetic pole portions of the lower magnetic pole layer and the upper magnetic pole layer in the thin-film magnetic head according to the first embodiment of the present invention. FIG. 9 is a sectional view of a thin-film magnetic head according to a second embodiment of the present invention. FIG. 10 is a cross-sectional view for explaining one step in a conventional method of manufacturing a thin-film magnetic head. FIG. 10 is a cross-sectional view for explaining a step following the step shown in FIG. 9. FIG. 11 is a cross-sectional view for explaining a step following the step shown in FIG. 10. FIG. 12 is a cross-sectional view for explaining a step following the step shown in FIG. 11. It is a top view of the conventional magnetic head.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Insulating layer, 3 ... Lower shield layer, 5 ... MR element, 8 ... Upper shield layer, 9 ... Insulating film, 10 ... Lower magnetic pole layer, 10a ... Magnetic pole partial layer, 10b ... Yoke partial layer, 11 ... insulating layer, 13 thin film coil, 15 ... coil insulating layer, 16 ... insulating layer, 17 ... recording gap layer, 18 ... upper magnetic pole layer, 20 ... overcoat layer, 30 ... air bearing surface.

Claims (8)

A first and a second magnetic layer magnetically coupled to each other with a medium facing surface facing the recording medium and including magnetic pole portions facing each other on the medium facing surface side, each including at least one layer; A gap layer provided between a magnetic pole part of the first magnetic layer and a magnetic pole part of the second magnetic layer, and at least a part between the first and second magnetic layers; A thin-film coil provided in a state insulated from the two magnetic layers,
The first magnetic layer has a first portion, one end of which is disposed on the medium facing surface, and a first portion disposed on a side opposite to the medium facing surface with respect to the first portion, and has a width larger than the width of the first portion. A second portion having a large width;
The second magnetic layer has a portion having one end disposed on the medium facing surface and having a width equal to a track width;
The thin-film magnetic head further includes insulating layers disposed on both sides of the first portion in the track width direction,
A width of a part of the first part on the gap layer side is smaller than a width of another part of the first part and equal to a track width;
The thin-film magnetic head according to claim 1, wherein a surface of the other portion of the first portion on the gap layer side and a surface of the insulating layer on the gap layer side form a flat surface.   The first magnetic layer has one surface adjacent to the gap layer, a pole portion layer including the first portion and the second portion, and a first portion connected to the other surface of the pole portion layer. 2. The thin-film magnetic head according to claim 1, further comprising a yoke portion layer serving as a yoke portion in the one magnetic layer.   3. The thin-film magnetic head according to claim 2, wherein at least a part of the thin-film coil is arranged on a side of the magnetic pole partial layer.   4. The thin-film magnetic head according to claim 2, wherein an end of the yoke partial layer on the medium facing surface side is arranged at a position away from the medium facing surface. A first and a second magnetic layer magnetically coupled to each other with a medium facing surface facing the recording medium and including magnetic pole portions facing each other on the medium facing surface side, each including at least one layer; A gap layer provided between a magnetic pole part of the first magnetic layer and a magnetic pole part of the second magnetic layer, and at least a part between the first and second magnetic layers; A thin-film magnetic head comprising: a thin-film coil provided insulated from the second magnetic layer;
Forming the first magnetic layer;
Forming the gap layer on the first magnetic layer;
Forming the second magnetic layer on the gap layer;
Forming the thin-film coil so that at least a part of the thin-film coil is disposed between the first and second magnetic layers while being insulated from the first and second magnetic layers. ,
The first magnetic layer has a first portion, one end of which is disposed on the medium facing surface, and a first portion disposed on a side opposite to the medium facing surface with respect to the first portion, and has a width larger than the width of the first portion. A second portion having a large width;
The second magnetic layer has a portion having one end disposed on the medium facing surface and having a width equal to a track width;
The method of manufacturing the thin-film magnetic head further comprises:
Forming insulating layers disposed on both sides of the first portion in the track width direction;
After the formation of the second magnetic layer, the width of a part of the first part on the gap layer side is smaller than the width of the other part of the first part and equal to the track width; Part of the first part and part of the insulating layer are etched so that the surface of the other part of the part on the gap layer side and the surface of the insulating layer on the gap layer side form a flat surface. And a method of manufacturing a thin-film magnetic head.   The first magnetic layer has one surface adjacent to the gap layer, a pole portion layer including the first portion and the second portion, and a first portion connected to the other surface of the pole portion layer. 6. The method for manufacturing a thin-film magnetic head according to claim 5, further comprising a yoke portion layer serving as a yoke portion in the one magnetic layer.   7. The method according to claim 6, wherein at least a part of the thin film coil is disposed on a side of the magnetic pole partial layer. 8. The method of manufacturing a thin-film magnetic head according to claim 6, wherein an end of the yoke partial layer on the medium facing surface side is arranged at a position away from the medium facing surface.

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