JP4112442B2 - Magnetic head, and head suspension assembly and magnetic disk apparatus using the same - Google Patents

Description

【０１４０】
【表２】

【０１４１】
【表３】

【０１４２】
サンプル１が本発明の実施例に相当し、サンプル２，３がそれぞれ比較例に相当している。表１〜３に示す層構成から、表１〜表３にそれぞれ示すように、サンプル１ではｄ２−ｄ１＝−３ｎｍ、サンプル２ではｄ２−ｄ１＝＋４ｎｍ、サンプル３ではｄ２−ｄ１＝＋３２ｎｍとなる。
【０１４３】
サンプル１，２では、ＴＷ＝０．１μｍ、ＭＲｈ＝Ｂｈａ＝Ｂｈｂ＝０．１μｍ、Ｗａ＝Ｗｂ＝０．５μｍとした。サンプル３では、ＴＷ＝０．１μｍとした。
【０１４４】
サンプル１〜３ともに、ウエハ工程終了後、バー状態に切断し、ラッピング処理としてダイヤモンド粒子でＴＭＲ素子２を直接研磨して、ＭＲハイトＭＲｈを０．１μｍと規定した。そして、サンプル１〜３ともに、ヘッド保護膜４としてダイヤモンドライクカーボン（ＤＬＣ）３ｎｍをつけて浮上型磁気ヘッドとして作製し、有効トラック幅、バルクハウゼンノイズ（ＢＨＮ）発生率を測定した。その結果を表４に示す。
【０１４５】
【表４】

【０１４６】
本発明の実施例に相当するサンプル１（形状異方性により大きな保磁力Ｈｃを持つ軟磁性層のみからなる縦バイアス層を使用したヘッド）においても、比較例に相当するサンプル２，３（従来の縦バイアス層を使用したヘッド）と同程度に、バルクハウゼンノイズを抑制することができることがわかる。そして、サンプル１では、サンプル２，３に比べてｄ２−ｄ１が小さくなることで、サイドシールド効果が増大し、有効トラック幅を狭くすることができる。
【０１４７】
以上、本発明の各実施の形態について説明したが、本発明はこれらの実施の形態に限定されるものではない。
【０１４８】
例えば、前述した実施の形態はＴＭＲヘッドに適用した例であるが、本発明は、ＣＰＰ−ＧＭＲヘッドなどのＣＰＰ構造を持つ磁気抵抗効果素子を有するヘッドや、ＣＩＰ構造を持つＧＭＲヘッドなどにも適用することができる。
【０１４９】
【発明の効果】
以上説明したように、本発明によれば、線方向及びトラック幅方向の記録密度を高めることができる磁気ヘッド、並びに、これを用いたヘッドサスペンションアセンブリ及び磁気ディスク装置を提供することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態による磁気ヘッドを模式的に示す概略斜視図である。
【図２】図１に示す磁気ヘッドのＴＭＲ素子及び誘導型磁気変換素子の部分を模式的に示す拡大断面図である。
【図３】図２中のＡ−Ａ’矢視概略図である。
【図４】図２中のＴＭＲ素子付近を更に拡大した拡大図である。
【図５】図３中のＴＭＲ素子付近を更に拡大した拡大図である。
【図６】図１に示す磁気ヘッドにおける所定層より下側の層の、Ｘ軸方向から見た位置関係を模式的に示す概略平面図である。
【図７】図１に示す磁気ヘッドの製造方法におけるウエハ工程を構成する一工程を模式的に示す図である。
【図８】図１に示す磁気ヘッドの製造方法におけるウエハ工程を構成する他の工程を模式的に示す図である。
【図９】図１に示す磁気ヘッドの製造方法におけるウエハ工程を構成する更に他の工程を模式的に示す図である。
【図１０】図１に示す磁気ヘッドの製造方法におけるウエハ工程を構成する更に他の工程を模式的に示す図である。
【図１１】本発明の第２の実施の形態による磁気ディスク装置の要部の構成を示す概略斜視図である。
【図１２】第１の従来例の磁気ヘッドのＴＭＲ素子付近を模式的に示す断面図である。
【図１３】図１２中のＦ−Ｆ’矢視概略図である。
【図１４】図１２に示す磁気ヘッドにおける所定層より下側の層の、Ｘ軸方向から見た位置関係を模式的に示す概略平面図である。
【図１５】図１２に示す磁気ヘッドの製造方法におけるウエハ工程を構成する一工程を模式的に示す図である。
【図１６】図１２に示す磁気ヘッドの製造方法におけるウエハ工程を構成する他の工程を模式的に示す図である。
【図１７】図１２に示す磁気ヘッドの製造方法におけるウエハ工程を構成する更に他の工程を模式的に示す図である。
【図１８】図１２に示す磁気ヘッドの製造方法におけるウエハ工程を構成する更に他の工程を模式的に示す図である。
【図１９】第２の従来例の磁気ヘッドのＴＭＲ素子付近を模式的に示す断面図である。
【図２０】図１９中のＬ−Ｌ’矢視概略図である。
【図２１】図１９に示す磁気ヘッドにおける所定層より下側の層の、Ｘ軸方向から見た位置関係を模式的に示す概略平面図である。
【図２２】図１９に示す磁気ヘッドの製造方法におけるウエハ工程を構成する一工程を模式的に示す図である。
【図２３】図１９に示す磁気ヘッドの製造方法におけるウエハ工程を構成する他の工程を模式的に示す図である。
【図２４】図１９に示す磁気ヘッドの製造方法におけるウエハ工程を構成する更に他の工程を模式的に示す図である。
【図２５】図１９に示す磁気ヘッドの製造方法におけるウエハ工程を構成する更に他の工程を模式的に示す図である。
【図２６】軟磁性層に関するパターニングなしのサンプルを模式的に示す図である。
【図２７】軟磁性層に関するパターニングありのサンプルを模式的に示す図である。
【図２８】図２６に示すサンプルのＭＨ曲線を示す図である。
【図２９】図２７に示すサンプルのＭＨ曲線を示す図である。
【符号の説明】
１ スライダ
２ ＴＭＲ素子
３ 誘導型磁気変換素子
２１ 下部磁気シールド層
２３ 下部金属層
２４ ピン層
２５ ピンド層
２６ トンネルバリア層
２７ フリー層
２８ 上部金属層（キャップ層）
２９ 上部金属層
３０ 絶縁層
３１ 上部磁気シールド層
３２ａ，３２ｂ 絶縁層
３３ａ，３３ｂ 下地層
３４ａ，３４ｂ 軟磁性層（縦バイアス層）
３５ａ，３５ｂ 保護層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnetic head, and a head suspension assembly and a magnetic disk apparatus using the magnetic head.
[0002]
[Prior art]
As the capacity of a hard disk drive (HDD) is reduced, a head with high sensitivity and high output is required. In response to this demand, the hard magneto-resistive head (GMR head), which is the current product, is undergoing hard improvement in characteristics, while the tunnel magnetoresistive head is expected to have a resistance change rate more than twice that of the GMR head. (TMR head) is also being developed vigorously.
[0003]
GMR heads and TMR heads generally have different head structures due to differences in the direction in which a sense current flows. In general, a CIP (Current In Plane) structure is a head structure that allows a sense current to flow parallel to the film surface, such as a GMR head, and a CPP (Current In Plane) head structure that allows a sense current to flow perpendicularly to the film surface, such as a TMR head. Perpendicular to Plane) structure. Since the CPP structure can use the magnetic shield itself as an electrode, the magnetic shield-element short circuit (insulation failure), which is a serious problem in narrowing the read gap of the CIP structure, does not occur essentially. Therefore, the CPP structure is very advantageous in increasing the recording density.
[0004]
As a magnetic head having a CPP structure, in addition to a TMR head, for example, a CPP-GMR having a CPP structure while using a spin valve film (including a specular type and a dual spin valve type magnetic multilayer film) as a magnetoresistive effect element. The head is also known.
[0005]
In a magnetic head using a spin valve film, a TMR film, or the like, in both the CIP structure and the CPP structure, in order to suppress Barkhausen noise, the free layer is divided into a single magnetic domain in the track width direction. A sufficient bias magnetic field is applied. If this bias magnetic field is insufficient, Barkhausen noise is generated and the head does not function. In general, a resist mask used for milling for defining the track width is used as it is, and a pair of bias layers (also referred to as a longitudinal bias layer or a magnetic domain control film) to which the bias magnetic field is applied by a lift-off method. Are formed on both sides in the track width direction (for example, Patent Documents 1 to 3). This structure is called an Abutted structure. As a method for applying the bias magnetic field, an exchange bias method using exchange coupling between an antiferromagnetic layer and a soft magnetic layer and a hard magnetic bias method using a hard magnetic layer are known. In the case of the exchange bias method, the bias layer is composed of a soft magnetic layer such as NiFe and CoFe, and an antiferromagnetic layer such as IrMn and RuRhMn that exchange-couples with the soft magnetic layer and fixes its magnetization direction. A static magnetic field generated by the soft magnetic layer fixed by exchange coupling is used as the bias magnetic field (for example, Patent Documents 1 and 2). In the case of the hard magnetic bias method, the bias layer is composed of a hard magnetic layer such as TiW / CoCrPt, Cr / CoCrPt, CrTi / CoCrPt, and the static magnetic field generated by the hard magnetic layer is used as the bias magnetic field ( For example, Patent Documents 1 and 3).
[0006]
In the magnetic head, the magnetoresistive layer and the bias layer are disposed between the upper magnetic shield layer and the lower magnetic shield layer so that the magnetic bits of the magnetic recording medium can be detected (for example, Patent Documents). 1-3). The narrower the gap between the upper magnetic shield layer and the lower magnetic shield layer at the portion sandwiching the magnetoresistive effect layer, the shorter the magnetic bit length that can be detected, and the higher the recording density. In the magnetic head having the CPP structure, a lead for flowing current to the magnetoresistive effect layer is provided separately from the upper magnetic shield layer and the lower magnetic shield layer. However, in the magnetic head having the CIP structure, current is supplied to the magnetoresistive effect layer. The upper electrode and the lower electrode may be provided separately from the upper magnetic shield layer and the lower magnetic shield layer, or the upper magnetic shield layer and the lower magnetic shield layer may be used as the upper electrode and the lower electrode.
[0007]
In the conventional magnetic head as described above, in any type of magnetic head, the distance between the upper magnetic shield layer and the lower magnetic shield layer near both sides in the track width direction of the magnetoresistive effect layer is the magnetoresistive effect. The distance between the upper magnetic shield layer and the lower magnetic shield layer at the portion sandwiching the layers is the same as or larger than the distance (for example, Patent Documents 1 to 3). In Patent Document 3, in the case of a TMR head, the length of the magnetic bit that can be detected is reduced by narrowing the distance between the upper magnetic shield layer and the lower magnetic shield layer at the portion sandwiching the magnetoresistive effect layer. In order to ensure electrical insulation between the upper magnetic shield layer and the lower magnetic shield layer when shortening and increasing the recording density, the upper magnetic shield layer near both sides in the track width direction of the magnetoresistive effect layer is used. It is described that it is preferable that the distance between the upper magnetic shield layer and the lower magnetic shield layer is larger than the distance between the upper magnetic shield layer and the lower magnetic shield layer at the portion sandwiching the magnetoresistive effect layer.
[0008]
As specific examples of the conventional magnetic head described above, the magnetic heads of the first and second conventional examples will be described below with reference to the drawings.
[0009]
[First Conventional Example]
[0010]
FIG. 12 is a cross-sectional view schematically showing the vicinity of the TMR element 2 of the magnetic head of the first conventional example. FIG. 13 is a schematic view taken along the line FF ′ in FIG. In order to facilitate understanding, the X axis, the Y axis, and the Z axis that are orthogonal to each other are defined as shown in FIGS. 12 and 13 (the same applies to the drawings described later). The direction of the arrow in the Z-axis direction is called the + Z direction or + Z side, and the opposite direction is called the -Z direction or -Z side, and the same applies to the X-axis direction and the Y-axis direction. The Z-axis direction coincides with the track width direction of the TMR element 2, and the surface on the + Y side of the protective film 4 described later forms an ABS (air bearing surface). This also applies to a second conventional example to be described later and the first embodiment of the present invention. FIG. 14 is a schematic plan view schematically showing the positional relationship of the layer below the upper metal layer 29 in the first conventional magnetic head as viewed from the X-axis direction.
[0011]
A TMR element 2 as a magnetoresistive effect element used as a reproducing magnetic head element is formed on a lower magnetic shield layer 21 and an upper side (+ X side) of the lower magnetic shield layer 21 as shown in FIGS. The lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper magnetic shield layer 31 and the magnetic shield layers 21 and 31, which are sequentially stacked from the lower magnetic shield layer 21 side. An upper metal layer (cap layer) 28 serving as a nonmagnetic metal layer serving as a protective film and an upper metal layer 29 serving as an underlayer for the upper magnetic shield layer 31 are provided. The pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, and the free layer 27 constitute a magnetoresistive effect layer. The actual TMR element 2 generally has a multi-layered film structure instead of the film structure of the number of layers as shown in the figure. However, in the magnetic head shown in FIG. The minimum film structure necessary for the basic operation of the element 2 is shown.
[0012]
In the first conventional example, the lower magnetic shield layer 21 and the upper magnetic shield layer 31 are also used as a lower electrode and an upper electrode, respectively. The magnetic shield layers 21 and 31 are made of a magnetic material such as NiFe, for example.
[0013]
The lower metal layer 23 is a conductor, and is composed of, for example, a two-layer film including a lower Ta layer and an upper NiFe layer. The pinned layer 24 is composed of an antiferromagnetic layer. The pinned layer 25 and the free layer 27 are each composed of a ferromagnetic layer. The magnetization direction of the pinned layer 25 is fixed in a predetermined direction by an exchange coupling bias magnetic field with the pinned layer 24. On the other hand, in the free layer 27, the direction of magnetization is freely changed in response to an external magnetic field that is basically magnetic information. For example, the tunnel barrier layer 26 is made of Al. ₂ O ₃ It is formed with materials such as.
[0014]
The upper metal layer 28 is made of Ta or the like, for example. The upper metal layer 29 serving as a base layer of the upper magnetic shield layer 31 is a conductor and is made of a nonmagnetic metal material such as Ta.
[0015]
As shown in FIG. 13, on both sides of the magnetoresistive effect layer in the Z-axis direction, a pair of longitudinal bias layers for applying a bias magnetic field for magnetic domain control to the free layer 27 mainly in the track width direction (Z-axis direction). (Magnetic domain control layer) is formed. In the first conventional example, the pair of longitudinal bias layers includes NiFe and CoFe soft magnetic layers 134a and 134b disposed on the −Z side and + Z side of the magnetoresistive layer, and soft magnetic layers 134a and 134a, respectively. It is composed of antiferromagnetic layers 134a ′ and 134b ′ such as IrMn and RuRhMn, which are laminated on 134b and are respectively exchange-coupled to soft magnetic layers 134a and 134b. That is, in the first conventional example, the exchange bias method described above is employed.
[0016]
Under the soft magnetic layers 134a and 134b, base layers 33a and 33b made of Ta or the like are formed, respectively. Insulating layers 32a and 32b are formed below the base layers 33a and 33b, respectively. The insulating layers 32a and 32b are also interposed between the base layers 33a and 33b and the end faces of the layers 23 to 28 on the + Z side and the −Z side, respectively, and the layers 23 to 28 are electrically connected by the base layers 33a and 33b and the like. There is no short circuit. The insulating layers 32a and 32b are made of Al. ₂ O ₃ Or SiO ₂ Etc. On the antiferromagnetic layers 134 a ′ and 134 b ′, the longitudinal bias layer (particularly in the first conventional example, the anti-ferromagnetic layer 134 a ′ and 134 b ′) is placed in the atmosphere before the upper metal layer 29 is formed. Protection layers 35a and 35b made of Ta or the like for protecting the ferromagnetic layers 35a and 35b) from oxidation or the like are formed.
[0017]
In the first conventional example, as shown in FIGS. 12 to 14, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are viewed from the X-axis direction. The size in plan view is defined according to the desired track width TW and MR height MRh. Strictly speaking, the layers 23 to 28 are ion-milled at the same time as will be described later, so that the size in plan view is determined, and their + Z side, −Z side and −Y side end faces are shown in FIGS. 13, the lower surface of the layers 23 to 28 is slightly larger, but it can be said that the sizes in plan view are substantially the same. In FIG. 14, only the upper metal layer 28 is shown for the layers 23 to 28, and the size in plan view is shown as TW × MRh. Note that the end surfaces on the + Y side (ABS side) of the layers 23 to 28 are determined by a lapping process described later, and are perpendicular to the film surface.
[0018]
In the first conventional example, as shown in FIGS. 13 and 14, the MR height direction (Y-axis direction) of the insulating layer 32a, the underlayer 33a, the soft magnetic layer 134a, the antiferromagnetic layer 134a ′, and the protective layer 35a is used. (Hereinafter simply referred to as “height direction”), and the width in the height direction (Y-axis direction) of the insulating layer 32b, the underlayer 33b, the soft magnetic layer 134b, the antiferromagnetic layer 134b ′, and the protective layer 35b. Bhb is substantially the same as the MR height MRh. As will be described later, the layers 23 to 28, the layers 32a, 33a, 134a, 134a ′, and 35a and the layers 32b, 33b, 134b, 134b ′, and 35b are simultaneously milled with respect to the height direction. Since the end surface on the Y side is defined, the end surface on the -Y side becomes a tapered surface corresponding to each material. Therefore, the width in the height direction of each layer is slightly different, but these widths are substantially the same. It can be said. In FIG. 14, for the layers 32a, 33a, 134a, 134a ′, and 35a, only the protective layer 35a is shown, and the width in the height direction is shown as Bha. Similarly, in FIG. 14, for the layers 32b, 33b, 134b, 134b ′, and 35b, only the protective layer 35b is shown, and the width in the height direction is shown as Bhb.
[0019]
Further, the lower magnetic shield layer 21 and the upper metal layer 29 are formed in the regions where the layers 23 to 28, the layers 32a, 33a, 134a, 134a ′, 35a, and the layers 32b, 33b, 134b, 134b ′, 35b are not formed. In between, Al ₂ O ₃ Or SiO ₂ An insulating layer 30 is formed.
[0020]
In the first conventional example, as shown in FIG. 13, the interval d2 is larger than the interval d1. The interval d2 is an effective region in the film surface direction that is effectively involved in magnetic detection in the magnetoresistive effect layer (in the first conventional example, a region in which a current flows in a direction substantially perpendicular to the film surface in the magnetoresistive effect layer. And the lower magnetic shield layer 21 and the upper magnetic shield layer 31 in the vicinity of both sides of the effective region in the track width direction (Z-axis direction) of the region that does not substantially overlap with the substantially entire region of the magnetoresistive layer. Is the interval between. The interval d1 is an interval between the lower magnetic shield layer 21 and the upper magnetic shield layer 31 in a region substantially overlapping with the effective region.
[0021]
Further, as shown in FIG. 13, the lower magnetic shield layer 21 is formed flat without any step at any location, and is substantially overlapped with the effective region from a region substantially overlapping with the effective region. It has substantially the same height (the height in the X-axis direction) over the region that should not be.
[0022]
Although the magnetic head of the first conventional example is not shown in the drawing, it is an inductive magnetic transducer element as a recording magnetic head element as in the magnetic head according to the first embodiment of the present invention to be described later. Are stacked on the TMR element 2 to form a composite magnetic head. In FIGS. 12 to 14, reference numeral 4 denotes a protective film made of a DLC film or the like formed on the ABS side.
[0023]
Next, an example of a manufacturing method of the magnetic head of the first conventional example will be described.
[0024]
First, a wafer process is performed. That is, Al to be the base ₂ O ₃ -Prepare a wafer 101 made of TiC or SiC, and form each of the above-described layers in the formation area of a large number of matrix-shaped magnetic heads on the wafer 101 so as to have the above-described structure by using a thin film forming technique or the like. .
[0025]
The outline of the wafer process will be described with reference to FIGS. 15 to 18 are diagrams schematically showing each process constituting the wafer process. FIGS. 15A, 16A, 17A, and 18A are schematic plan views, respectively. It is. 15B is a schematic cross-sectional view taken along the line GH in FIG. 15A, FIG. 16B is a schematic cross-sectional view taken along the line GH in FIG. 16A, and FIG. (B) is a schematic cross-sectional view along the line JK in FIG. 17 (a), FIG. 18 (b) is a schematic cross-sectional view along the line GH in FIG. 18 (a), and FIG. ) Is a schematic cross-sectional view along the line JK in FIG. In FIG. 16A, TW indicates the track width defined by the TMR element 2.
[0026]
In the wafer process, first, the underlayer 16, the lower magnetic shield layer 21, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are sequentially formed on the wafer 101. Laminate (FIG. 15).
[0027]
Next, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are partially removed and patterned by first ion milling. Next, insulating layers 32a and 32b, base layers 33a and 33b, soft magnetic layers 134a and 134b, antiferromagnetic layers 134a ′ and 134b ′, and protective layers 35a and 35b are sequentially formed on the removed portion by a lift-off method. (FIG. 16). The region where the resist mask used in the first ion milling is formed is a region excluding the regions of the protective layers 35a and 35b in FIG.
[0028]
Next, by the second ion milling, the lower metal layer 23, leaving a band-shaped portion having a necessary width (width in the Y-axis direction) in the height direction of the TMR element 2 and extending in the Z-axis direction by a predetermined length, The pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, the upper metal layer 28, the soft magnetic layers 134a and 134b, the antiferromagnetic layers 134a ′ and 134b ′, and the protective layers 35a and 35b are partially removed. And patterning. The insulating layers 32a and 32b and the base layers 33a and 33b may also be removed by the second ion milling. Next, an insulating film 30 is formed on the removed portion by a lift-off method (FIG. 17). Note that the region where the resist mask used in the second ion milling is formed is the region of the protective layers 28, 35a, and 35b in FIG.
[0029]
In FIG. 17A, the outer shapes of the protective films 35a and 35b before the second ion milling are indicated by imaginary lines. In this regard, compare FIG. 17 (a) with FIG. 16 (a). In this manufacturing method, the thicknesses, materials, and the like of the protective layers 35a and 35b are determined by the second ion milling in the soft magnetic layers 134a and 134b and the antiferromagnetic layers 134a ′ and 134b ′ in the region where the resist mask is not formed. The protective layers 35a and 35b are completely removed. Therefore, the protective layers 35a and 35b are relatively thin.
[0030]
Thereafter, the upper metal layer 29 is formed by sputtering or the like, and further the magnetic shield layer 31 is formed by plating or the like (FIG. 18). Finally, the inductive magnetic transducer and the like are formed. Thereby, the wafer process is completed.
[0031]
Next, the magnetic head is completed through a known process on the wafer that has been subjected to the wafer process. Briefly, each bar (bar-shaped magnetic head assembly) in which a plurality of magnetic head portions are arranged in a line on a substrate is cut out from the wafer. Next, lapping (polishing) is performed on the ABS side in order to set the throat height, MR height, and the like for the bar. Next, the protective film 4 and the like are formed on the ABS side. Finally, the bar is separated into individual magnetic heads by cutting. Thereby, the magnetic head of the first conventional example is completed.
[0032]
In the first conventional example described above, instead of the soft magnetic layer 134a and the antiferromagnetic layer 134a ′, and the soft magnetic layer 134b and the antiferromagnetic layer 134b ′ as the pair of longitudinal bias layers, TiW / CoCrPt It is conceivable to form a hard magnetic layer such as Cr / CoCrPt or CrTi / CoCrPt. That is, as in the first conventional example, it is considered to adopt the hard magnetic bias method while making the widths Bha and Bhb in the height direction of the longitudinal bias layer substantially the same as the MR height MRh (see FIG. 14). It is done. However, such a structure is not generally adopted for the following reason. That is, the particle size of the hard magnetic material (CoCrPt, CoPt, etc.) used in the hard magnetic bias method is larger than the particle size of a typical soft magnetic material (NiFe, CoFe, etc.) used in the exchange bias method. Generally large. Since this size is not negligible compared with the MR height MRh (˜100 nm), if the hard magnetic bias method is adopted when Bha = Bhb = MRh, a sufficient bias magnetic field is applied to the free layer 27. Cannot be done, and the yield is reduced. Therefore, when Bha = Bhb = MRh, the hard magnetic bias method is not currently used. Since the particle diameter of typical soft magnetic materials (NiFe, CoFe, etc.) used in the exchange bias method is generally small, even if Bha = Bhb = MRh as in the first conventional example, There is no problem in terms of diameter.
[0033]
[Second Conventional Example]
[0034]
FIG. 19 is a cross-sectional view schematically showing the vicinity of the TMR element 2 of the magnetic head of the second conventional example. FIG. 20 is a schematic view taken along line LL ′ in FIG. FIG. 21 is a schematic plan view schematically showing the positional relationship of the layer below the upper metal layer 29 in the second conventional magnetic head as viewed from the X-axis direction. FIGS. 19 to 21 correspond to FIGS. 12 to 14, respectively. 19 to 21, elements that are the same as or correspond to those in FIGS. 12 to 14 are given the same reference numerals, and redundant descriptions thereof are omitted.
[0035]
The magnetic head of the second conventional example is different from the magnetic head of the first conventional example only in the points described below.
[0036]
In the first conventional example, the soft magnetic layer 134a and the antiferromagnetic layer 134a ′, and the soft magnetic layer 134b and the antiferromagnetic layer 134b ′ are formed as the pair of longitudinal bias layers. In the conventional example of FIG. 2, a pair of hard magnetic layers 234a and 234b such as TiW / CoCrPt, Cr / CoCrPt, and CrTi / CoCrPt are formed instead as a pair of longitudinal bias layers. That is, in the first conventional example, the exchange bias method is adopted, whereas in the second conventional example, the hard magnetic bias method is adopted.
[0037]
In the first conventional example, as shown in FIGS. 13 and 14, the soft magnetic layer 134a, the antiferromagnetic layer 134a ′, and the protective layer 35a are formed only in the region corresponding to the region R2 in FIG. In addition, the soft magnetic layer 134b, the antiferromagnetic layer 134b ′, and the protective layer 35b are formed only in the region corresponding to the region R4 in FIG. On the other hand, in the second conventional example, as shown in FIGS. 20 and 21, the hard magnetic layer 234a and the protective layer 35a are formed not only in the region R2 but also in the region R1, and the hard magnetic layer 234b and The protective layer 35b is formed not only in the region R4 but also in the region R3. Therefore, in the first conventional example, the width Bha, Bhb in the height direction of the vertical bias layer is substantially the same as the MR height MRh, whereas in the second conventional example, the width of the vertical bias layer in the height direction is substantially the same. The widths Bha and Bhb are considerably larger than the MR height MRh.
[0038]
The thickness of the protective layer 35a in the region R2 and the thickness of the protective film 35b in the region R4 in the second conventional example are larger than the thickness of the protective films 35a and 35b in the first conventional example. This is because the protective films 35a and 35b function as a mask for second ion milling in the manufacturing process described later in order to leave the hard magnetic layers 234a and 234b in the regions R1 and R3.
[0039]
Accordingly, as shown in FIG. 20, in the second conventional example, the distance d2 is larger than the distance d1 as in the first conventional example, but d2-d1 is larger than that in the second conventional example. Is larger than the first conventional example.
[0040]
In the second conventional example, the thickness of the protective layer 35a in the region R1 and the thickness of the protective film 35b in the region R3 are the same as the thickness of the protective layer 35a in the region R2 and the protective film 35b in the region R4. Thinner than the thickness. This is because the upper surfaces of the regions R2 and R4 of the protective films 35a and 35b are partially removed by second ion milling in the manufacturing process described later.
[0041]
Next, an example of a manufacturing method of the magnetic head of the second conventional example will be described. The manufacturing method differs from the first conventional magnetic head manufacturing method only in the wafer process. For this reason, only the wafer process in the manufacturing method of the magnetic head of the second conventional example will be described here.
[0042]
An outline of the wafer process will be described with reference to FIGS. 22 to 25 are diagrams schematically showing each process constituting the wafer process, and FIGS. 22 (a), 23 (a), 24 (a), and 25 (a) are schematic plan views, respectively. It is. 22B is a schematic cross-sectional view along the line MN in FIG. 22A, FIG. 23B is a schematic cross-sectional view along the line MN in FIG. 23A, and FIG. (B) is a schematic cross-sectional view along the line PQ in FIG. 24 (a), FIG. 25 (b) is a schematic cross-sectional view along the line MN in FIG. 25 (a), and FIG. ) Is a schematic cross-sectional view along the line PQ in FIG. In FIG. 23A, TW indicates a track width defined by the TMR element 2.
[0043]
In the wafer process, first, the underlayer 16, the lower magnetic shield layer 21, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are sequentially formed on the wafer 101. Laminate (FIG. 22).
[0044]
Next, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are partially removed and patterned by first ion milling. Next, insulating layers 32a and 32b, base layers 33a and 33b, hard magnetic layers 234a and 234b, and protective layers 35a and 35b are sequentially formed on the removed portion by a lift-off method (FIG. 23). In this manufacturing method, the thicknesses, materials, and the like of the protective layers 35a and 35b are determined so that the protective layers 35a and 35b function as a mask for second ion milling described later. Therefore, the protective layers 35a and 35b are relatively thick. The region where the resist mask used in the first ion milling is formed is a region excluding the regions of the protective layers 35a and 35b in FIG.
[0045]
Next, by second ion milling, a resist mask is formed on a band-shaped portion having a necessary width (width in the Y-axis direction) in the height direction of the TMR element 2 and extending in the Z-axis direction by a predetermined length. The lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are partially removed and patterned. At this time, since the thickness, material, and the like of the protective layers 35a and 35b are determined so that the protective films 35a and 35b function as a mask as described above, in the region where the resist mask is not formed, the second layer is formed. Although the thickness of the protective films 35a and 35b is reduced by the ion milling, the protective films 35a and 35b remain in this region. Next, an insulating film 30 is formed by a lift-off method in a portion other than the region where the resist mask is formed (FIG. 24).
[0046]
Thereafter, the upper metal layer 29 is formed by sputtering or the like, and further the magnetic shield layer 31 is formed by plating or the like (FIG. 25). Finally, the inductive magnetic transducer and the like are formed. Thereby, the wafer process is completed.
[0047]
In the second conventional example, the hard magnetic bias method is employed, but the widths Bha and Bhb in the height direction of the hard magnetic layers 234a and 234b as the longitudinal bias layers are considerably larger than the MR height MRh. There is no problem in terms of particle size.
[0048]
In the second conventional example described above, a soft magnetic layer and an antiferromagnetic layer may be formed as a pair of longitudinal bias layers instead of the hard magnetic layers 234a and 234b. That is, the exchange bias method may be employed while the widths Bha and Bhb in the height direction of the vertical bias layer are considerably larger than the MR height MRh (see FIG. 21). Further, there is a case where the intermediate state between the first conventional example and the second conventional example, that is, the second ion milling, mills from the protective layers 35a and 35b to the middle of the insulating layers 32a and 32b. However, this is not very preferable from the viewpoint of suppressing the bias layer.
[0049]
The magnetic heads of the first and second conventional examples have been described above.
[0050]
By the way, in Non-Patent Document 1, when a soft magnetic layer is patterned into a rectangular shape and the aspect ratio of the rectangular shape is increased, the soft magnetic layer can be obtained without using an antiferromagnetic layer exchange-coupled to the soft magnetic layer. It is disclosed that the coercive force Hc in the free direction of the layer can be increased. However, Non-Patent Document 1 simply refers to the relationship between the shape of the soft magnetic layer and the magnetic characteristics of the soft magnetic layer. Non-Patent Document 1 describes a soft magnetic layer having a high aspect ratio as a free layer included in a magnetoresistive effect layer in a magnetic head without using an antiferromagnetic layer that fixes the magnetization direction of the soft magnetic layer by exchange coupling. The use of a single magnetic domain does not disclose or suggest anything.
[0051]
[Patent Document 1]
JP 2000-30223 A
[Patent Document 2]
Japanese Patent Laid-Open No. 2001-14616
[Patent Document 3]
JP-A-11-213351
[Non-Patent Document 1]
Jing Shi, 6 others, "End Domain States and Magnetization Reversal in Submicron Magnetic Structures", IEEE TRANSACTIONS ON MAGNETICS, July 1998, Vol.34, No.4, p.997-999
[0052]
[Problems to be solved by the invention]
As described above, in any conventional magnetic head, the distance between the upper magnetic shield layer and the lower magnetic shield layer in the vicinity of both sides in the track width direction of the magnetoresistive effect layer (the distance d2 in FIGS. 13 and 20). Is equivalent to or larger than the distance between the upper magnetic shield layer and the lower magnetic shield layer (corresponding to the distance d1 in FIGS. 13 and 20) between the magnetoresistive effect layers. It had been. That is, d2−d1 ≧ 0. As described above, as described in Patent Document 3, it has been considered preferable to increase d2-d1.
[0053]
However, when d2-d1 is increased, for example, the upper magnetic shield layer is far away from the position directly beside the magnetoresistive effect layer on both sides of the magnetoresistive effect layer in the track width direction. For this reason, a result that a read gap (Read Gap) is widened is brought about, and it is difficult to increase the recording density in the linear direction. In addition, since the upper magnetic shield layer is far away from the position directly next to the magnetoresistive effect layer on both sides in the track width direction of the magnetoresistive effect layer, side reading increases, and accordingly, the track width direction It is difficult to increase the recording density.
[0054]
In the case of a magnetic head in which the widths Bha and Bhb in the height direction of each vertical bias layer are larger than the MR height MRh as in the second conventional example (for convenience of explanation, it is referred to as “Wide type magnetic head”). Since the protective films 35a and 35b must be thickened so that the layers 35a and 35b can function as a mask for the second ion milling, the thickness of the protective films 35a and 35b becomes relatively large, and d2- d1 becomes large. On the other hand, a magnetic head in which the widths Bha and Bhb in the height direction of the respective longitudinal bias layers are substantially the same as the MR height MRh as in the first conventional example (for convenience of explanation, “Narrow type magnetic head” In this case, the protective films 35a and 35b are thin, so d2-d1 is small. Therefore, the Narrow type magnetic head is advantageous in achieving higher recording density in the linear direction and the track width direction than the Wide type magnetic head.
[0055]
However, as described above, the particle size of the hard magnetic material is so large that it cannot be ignored compared with the MR height MRh (˜100 nm). Therefore, when the hard magnetic bias method is adopted, a sufficient bias magnetic field is applied to the free layer and the magnetic layer is high. In order to obtain the yield, the Wide type is generally adopted. On the other hand, in the exchange bias method in which the narrow type can be adopted in terms of particle size and d2-d1 can be made relatively small, the longitudinal bias layer is a combination of a soft magnetic layer and an antiferromagnetic layer. D2-d1 could not be reduced by the thickness of the antiferromagnetic layer.
[0056]
Further, when the exchange bias method is adopted, the exchange coupling between the soft magnetic layer and the antiferromagnetic layer disappears at about 200 ° C. or less depending on the case, and temperature characteristics (blocking temperature, dispersion) There was also a problem. Incidentally, a temperature of about 200 ° C. is a temperature generally used in a wafer process such as resist baking.
[0057]
The present invention has been made in view of such circumstances, and provides a magnetic head capable of increasing the recording density in the linear direction and the track width direction, and a head suspension assembly and a magnetic disk apparatus using the magnetic head. With the goal.
[0058]
[Means for Solving the Problems]
In order to solve the above problems, a magnetic head according to a first aspect of the present invention includes a base, first and second magnetic shield layers formed on one surface side of the base, and the first magnetic shield. And a magnetoresistive effect layer formed so as to be sandwiched between the first magnetic shield layer and the second magnetic shield layer, and an interval between the first magnetic shield layer and the second magnetic shield layer is The effective region substantially does not overlap with the effective region in the film surface direction that is effectively involved in magnetic detection in the magnetoresistive effect layer, at least in the region near both sides in the track width direction of the effective region. Is smaller than the overlapping region.
[0059]
According to the first aspect, for example, the upper magnetic shield layer approaches the position directly beside the magnetoresistive effect layer on both sides of the magnetoresistive effect layer in the track width direction. For this reason, the recording density in the linear direction can be increased without causing a result that the read gap is widened. In addition, since the upper magnetic shield layer approaches the position directly beside the magnetoresistive effect layer on both sides in the track width direction of the magnetoresistive effect layer, side reading is reduced, thereby increasing the recording density in the track width direction. Can do.
[0060]
Setting the distance between the first magnetoresistive effect layer and the second magnetic shield layer as in the first aspect, as described in Patent Document 3, This is contrary to the fact that it is considered preferable to widen the gap between the two magnetic shield layers on both sides of the magnetoresistive effect layer in the track width direction in order to ensure a proper insulation. However, according to the experiments of the present inventors, even if the distance between the first magnetoresistive effect layer and the second magnetic shield layer is set as in the first embodiment, the electrical It has been found that insulation can be ensured.
[0061]
In order to further increase the recording density in the linear direction and the track width direction, the distance between the first magnetic shield layer and the second magnetic shield layer is set in a region near both sides in the track width direction. More preferably, it is 3 nm or more smaller than in the region substantially overlapping with the effective region.
[0062]
The magnetic head according to a second aspect of the present invention is the magnetic head according to the first aspect, wherein the base-side magnetic shield layer of the first and second magnetic shield layers substantially overlaps the effective area. To a region that does not substantially overlap the effective region, and has substantially the same height.
[0063]
According to the second aspect, it is not necessary to form a step or the like in the magnetic shield layer on the substrate side, which is preferable because the manufacturing becomes easy.
[0064]
A magnetic head according to a third aspect of the present invention is the magnetic head according to the first or second aspect, wherein the magnetoresistive effect layer includes a free layer, and applies a bias magnetic field to the free layer mainly in the track width direction. And the pair of bias layers are disposed on both sides of the magnetoresistive effect layer in the track width direction between the first magnetic shield layer and the second magnetic shield layer. It is.
[0065]
The third aspect is an example in which the Abutted structure is adopted. However, in the first and second aspects, it is not always necessary to adopt the Abutted structure.
[0066]
A magnetic head according to a fourth aspect of the present invention is the magnetic head according to the third aspect, wherein each of the bias layers includes a soft magnetic layer but does not include an antiferromagnetic layer exchange-coupled to the soft magnetic layer.
[0067]
According to the fourth aspect, since each bias layer does not include an antiferromagnetic layer, as compared with a case where an exchange bias method using an antiferromagnetic layer exchange-coupled to the soft magnetic layer is employed, The effective distance between the first and second magnetic shield layers in the vicinity of both sides in the track width direction of the effective region out of the region that does not substantially overlap the effective region is set by the thickness of the antiferromagnetic layer. The distance between the first and second magnetic shield layers in the region substantially overlapping with the region can be made smaller. Therefore, according to the fourth aspect, the recording density in the linear direction and the track width direction can be further increased. Also, the side reading is reduced by the soft magnetic layer, and the recording density in the track width direction can be further increased.
[0068]
Even if the bias layer does not include an antiferromagnetic layer as in the fourth aspect, the bias magnetic field sufficient to suppress Barkhausen noise can be applied to the free layer by appropriately setting the shape of the soft magnetic layer. The present inventor confirmed by experiment that it can give.
[0069]
Further, according to the fourth aspect, each bias layer does not use an antiferromagnetic layer, and the Curie temperature of a typical soft magnetic material (NiFe, CoFe, etc.) is 500 ° C., At about 200 ° C., the temperature characteristics are also good.
[0070]
A magnetic head according to a fifth aspect of the present invention includes a base, first and second magnetic shield layers formed on one surface of the base, the first magnetic shield layer, and the second magnetic shield. A magnetoresistive effect layer including a free layer formed so as to be sandwiched between a shield layer and a pair of bias layers for applying a bias magnetic field to the free layer mainly in a track width direction. Are arranged on both sides of the magnetoresistive effect layer in the track width direction between the first magnetic shield layer and the second magnetic shield layer, and each bias layer includes a soft magnetic layer. It does not include an antiferromagnetic layer exchange-coupled with the soft magnetic layer.
[0071]
According to the fifth aspect, since each bias layer does not include an antiferromagnetic layer, as compared with a case where an exchange bias method using an antiferromagnetic layer exchange-coupled to the soft magnetic layer is employed, The first and second regions in regions near both sides of the effective region in the track width direction out of regions that do not substantially overlap with the effective region (effective region in the film surface direction that is effectively involved in magnetic detection in the magnetoresistive effect layer) The distance between the two magnetic shield layers can be reduced by the thickness of the antiferromagnetic layer. Therefore, according to the fifth aspect, the recording density in the linear direction and the track width direction can be increased.
[0072]
Further, according to the fifth aspect, since each bias layer does not use an antiferromagnetic layer, and the Curie temperature of a typical soft magnetic material (NiFe, CoFe, etc.) is 500 ° C., At about 200 ° C., the temperature characteristics are also good.
[0073]
A magnetic head according to a sixth aspect of the present invention is the magnetic head according to the fourth or fifth aspect, wherein the ratio of the width in the track width direction to the width in the MR height direction of the soft magnetic layer of each bias layer is 5 or more. It is what is. The MR height direction is a direction orthogonal to the recording medium facing surface.
[0074]
As in the sixth aspect, when the ratio is set to 5, Barkhausen noise can be suppressed to the same extent as in the past, and it has been confirmed by experiments of the present inventors. It is disclosed in Non-Patent Document 1 that the larger the ratio, the higher the coercive force Hc in the free direction of the soft magnetic layer. Therefore, the sixth aspect is preferable because a sufficient bias magnetic field for suppressing Barkhausen noise can be applied to the free layer.
[0075]
A magnetic head according to a seventh aspect of the present invention is the magnetic head according to any one of the fourth to sixth aspects, wherein the soft magnetic layer has a coercivity in the track width direction of 650 [Oe] or more.
[0076]
If the coercive force in the track width direction of the soft magnetic layer is 650 [Oe] or more as in the seventh aspect, it is preferable because Barkhausen noise can be significantly suppressed.
[0077]
In a magnetic head according to an eighth aspect of the present invention, in any one of the third to seventh aspects, the width in the MR height direction of each bias layer is effectively involved in magnetic detection in the magnetoresistive layer. The effective area in the film surface direction is substantially the same as the width in the MR height direction.
[0078]
According to the eighth aspect, since the above-described narrow type is employed, the first and second magnetic fields on both sides in the track width direction of the magnetoresistive effect layer are compared with the case where the above-described wide type is employed. The space between the shield layers can be further reduced. Therefore, according to the eighth aspect, the recording density in the linear direction and the track width direction can be further increased.
[0079]
A magnetic head according to a ninth aspect of the present invention is the magnetic head according to any one of the first to eighth aspects, wherein the effective region in the film surface direction that is effectively involved in magnetic detection in the magnetoresistive effect layer is the magnetoresistive effect. A layer is a region in which a current flows in a direction substantially perpendicular to the film surface.
[0080]
The ninth aspect is an example in which the CPP structure is adopted. However, in the first to eighth aspects, a CIP structure may be adopted.
[0081]
A magnetic head according to a tenth aspect of the present invention is the magnetic head according to the ninth aspect, wherein the magnetoresistive effect layer includes a tunnel barrier layer formed on one surface side of the free layer, and the free of the tunnel barrier layer. A pinned layer formed on the side opposite to the layer, and a pinned layer formed on the side of the pinned layer opposite to the tunnel barrier layer.
[0082]
The tenth aspect is an example in which the ninth aspect is applied to a TMR element. However, the ninth aspect is not limited to a TMR element, and is applied to, for example, a CPP-GMR element. May be.
[0083]
A head suspension assembly according to an eleventh aspect of the present invention includes a magnetic head, and a suspension that is mounted near the tip of the magnetic head and supports the magnetic head, and the magnetic head includes the first to tenth magnetic heads. The magnetic head according to any one of the aspects.
[0084]
According to the eleventh aspect, since the magnetic head according to any one of the first to tenth aspects is used, it is possible to increase the recording density of the magnetic disk device or the like.
[0085]
A magnetic disk apparatus according to a twelfth aspect of the present invention includes the head suspension assembly according to the eleventh aspect, an arm portion that supports the assembly, and an actuator that moves the arm portion to position the magnetic head. It is provided.
[0086]
According to the twelfth aspect, since the head suspension assembly according to the eleventh aspect is used, it is possible to increase the recording density and the like.
[0087]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a magnetic head according to the present invention, and a head suspension assembly and a magnetic disk apparatus using the magnetic head will be described with reference to the drawings.
[0088]
[First Embodiment]
[0089]
FIG. 1 is a schematic perspective view schematically showing a magnetic head according to a first embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view schematically showing portions of the TMR element 2 and the inductive magnetic transducer 3 of the magnetic head shown in FIG. 3 is a schematic view taken along the line AA ′ in FIG. FIG. 4 is an enlarged view in which the vicinity of the TMR element 2 in FIG. 2 is further enlarged. FIG. 5 is an enlarged view in which the vicinity of the TMR element 2 in FIG. 3 is further enlarged. FIG. 6 is a schematic plan view schematically showing the positional relationship of the layer below the upper metal layer 29 in the magnetic head according to the present embodiment as viewed from the X-axis direction. In these drawings, the X-axis direction coincides with the moving direction of the magnetic recording medium. The Z-axis direction coincides with the track width direction of the TMR element 2.
[0090]
4 to 6 correspond to FIGS. 12 to 14, respectively. 1 to 6, the same or corresponding elements as those in FIGS. 12 to 14 are denoted by the same reference numerals.
[0091]
As shown in FIG. 1, the magnetic head according to the first embodiment includes a slider 1 as a substrate, a TMR element 2 as a magnetoresistive effect element used as a reproducing magnetic head element, and a recording magnetic head element. And a protective film 4 made of a DLC film or the like, and configured as a composite magnetic head. However, the magnetic head according to the present invention may include only the TMR element 2, for example. In the first embodiment, one element 2 and three elements are provided, but the number is not limited at all.
[0092]
The slider 1 has rail portions 11 and 12 on the surface facing the magnetic recording medium, and the surfaces of the rail portions 11 and 12 constitute an ABS (air bearing surface). In the example illustrated in FIG. 1, the number of rail portions 11 and 12 is two, but is not limited thereto. For example, it may have 1 to 3 rail portions, and the ABS may be a flat surface having no rail portions. In addition, various geometric shapes may be attached to the ABS to improve the flying characteristics. The magnetic head according to the present invention may have any type of slider.
[0093]
In the first embodiment, the protective film 4 is provided only on the surfaces of the rail portions 11 and 12, and the surface of the protective film 4 constitutes ABS. However, the protective film 4 may be provided on the entire surface of the slider 1 facing the magnetic recording medium. Moreover, although it is preferable to provide the protective film 4, it is not always necessary to provide the protective film 4.
[0094]
As shown in FIG. 1, the TMR element 2 and the inductive magnetic conversion element 3 are provided on the air outflow end portion TR side of the rail portions 11 and 12. The recording medium moving direction coincides with the X-axis direction in the figure, and coincides with the outflow direction of air that moves when the magnetic recording medium moves at high speed. Air enters from the inflow end LE and flows out from the outflow end TR. Bonding pads 5 a and 5 b connected to the TMR element 2 and bonding pads 5 c and 5 d connected to the inductive magnetic transducer 3 are provided on the end face of the air outflow end TR of the slider 1.
[0095]
As shown in FIGS. 2 and 3, the TMR element 2 and the inductive magnetic conversion element 3 are stacked on a base layer 16 provided on a ceramic base 15 constituting the slider 1. The ceramic substrate 15 is usually made of Altic (Al ₂ O ₃ -TiC) or SiC. Al ₂ O ₃ In the case of using -TiC, since this is conductive, for example, Al ₂ O ₃ An insulating film made of is used. The underlayer 16 may not be provided depending on circumstances.
[0096]
As shown in FIGS. 4 and 5, the TMR element 2 includes a lower magnetic shield layer 21 formed on the underlayer 16 and an upper magnetic layer formed on the upper side of the lower magnetic shield layer 21 (on the side opposite to the base 15). The lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the protective film, which are laminated in order from the lower magnetic shield layer 21 side between the shield layer 31 and the magnetic shield layers 21 and 31. An upper metal layer (cap layer) 28 as a nonmagnetic metal layer, and an upper metal layer 29 as an underlayer of the upper magnetic shield layer 31. The pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, and the free layer 27 constitute a magnetoresistive effect layer. The actual TMR element 2 generally has a multi-layered film structure instead of the film structure of the number of layers as shown in the figure. However, in the magnetic head shown in FIG. The minimum film structure necessary for the basic operation of the element 2 is shown.
[0097]
In the first embodiment, the lower magnetic shield layer 21 and the upper magnetic shield layer 31 are also used as a lower electrode and an upper electrode, respectively. The magnetic shield layers 21 and 31 are made of a magnetic material such as NiFe, for example. Although not shown in the drawing, these magnetic shield layers 21 and 31 are electrically connected to the above-described bonding pads 5a and 5b, respectively. Needless to say, a lower electrode and an upper electrode may be provided separately from the lower magnetic shield layer 21 and the upper magnetic shield layer 31.
[0098]
The lower metal layer 23 is a conductor, and is composed of, for example, a two-layer film including a lower Ta layer and an upper NiFe layer. The pinned layer 24 is composed of an antiferromagnetic layer, and is preferably formed of a Mn-based alloy such as PtMn, IrMn, RuRhMn, FeMn, NiMn, PdPtMn, RhMn, or CrMnPt. The pinned layer 25 and the free layer 27 are each composed of a ferromagnetic layer, and are formed of a material such as Fe, Co, Ni, FeCo, NiFe, CoZrNb, or FeCoNi, for example. The magnetization direction of the pinned layer 25 is fixed in a predetermined direction by an exchange coupling bias magnetic field with the pinned layer 24. On the other hand, in the free layer 27, the direction of magnetization is freely changed in response to an external magnetic field that is basically magnetic information. The pinned layer 25 and the free layer 27 are not limited to a single layer. For example, a combination of a pair of magnetic layers having antiferromagnetic coupling and a nonmagnetic metal layer sandwiched therebetween. You may use the laminated body which consists of. An example of such a laminate is a ferromagnetic layer made of a three-layered CoFe / Ru / CoFe. In the present embodiment, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, and the free layer 27 are arranged in this order from the lower magnetic shield layer 21 side, but the free layer 27, The tunnel barrier layer 26, the pinned layer 25, and the pinned layer 24 may be disposed in this order. For example, the tunnel barrier layer 26 is made of Al. ₂ O ₃ , NiO, GdO, MgO, Ta ₂ O ₅ , MoO ₂ TiO ₂ Or WO ₂ Formed of a material such as
[0099]
For example, the upper metal layer 28 may be a single layer film or a composite layer using a single substance of Ta, Rh, Ru, Os, W, Pd, Pt, or Au, or an alloy made of a combination of any two or more of these. It is formed of a layer film.
[0100]
The upper metal layer 29 serving as a base layer of the upper electrode 31 is a conductor and is formed of a nonmagnetic metal material such as Ta. In this example, the upper metal layer 29 is provided in order to maintain a magnetic shield gap (gap between the magnetic shield layers 21 and 31) at a desired interval. However, it is not always necessary to provide the upper metal layer 29.
[0101]
As shown in FIGS. 3 and 5, on both sides of the magnetoresistive layer in the Z-axis direction, a pair of magnetic fields for applying a bias magnetic field for magnetic domain control to the free layer 27 mainly in the track width direction (Z-axis direction). A longitudinal bias layer (magnetic domain control layer) is formed. In the first embodiment, the pair of longitudinal bias layers is composed of soft magnetic layers 34a and 34b such as NiFe and CoFe disposed on the −Z side and the + Z side of the magnetoresistive effect layer, respectively. Unlike the conventional example of FIG. 1, it does not include an antiferromagnetic layer exchange-coupled to the soft magnetic layers 34a and 34b.
[0102]
Under the soft magnetic layers 34a and 34b, underlying layers 33a and 33b made of Ta or the like are formed, respectively. However, the base layers 33a and 33b are not necessarily provided. Insulating layers 32a and 32b are formed below the base layers 33a and 33b, respectively. The insulating layers 32a and 32b are also interposed between the base layers 33a and 33b and the end faces of the layers 23 to 28 on the + Z side and the −Z side, respectively, and the layers 23 to 28 are electrically connected by the base layers 33a and 33b and the like. There is no short circuit. The insulating layers 32a and 32b are made of Al. ₂ O ₃ Or SiO ₂ Etc. On the soft magnetic layers 34a and 34b, the longitudinal bias layer (in this embodiment, the soft magnetic layers 34a and 34b) is temporarily placed in the atmosphere before the formation of the upper metal layer 29 for convenience of the manufacturing process. Protective layers 35a and 35b made of Ta or the like for protecting the substrate from oxidation or the like are formed. The protective films 35a and 35b are preferably provided, but are not necessarily provided.
[0103]
In the first embodiment, as shown in FIGS. 4 to 6, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27 and the upper metal layer 28 are viewed from the X-axis direction. The size in plan view is defined according to the desired track width TW and MR height MRh. Strictly speaking, the layers 23 to 28 are ion-milled at the same time as described later to determine the size in plan view, and their + Z side, −Z side and −Y side end faces are shown in FIGS. 5, the lower layer of the layers 23 to 28 is slightly larger, but it can be said that the sizes in plan view are substantially the same. In FIG. 6, only the upper metal layer 28 is shown for the layers 23 to 28, and the size in plan view is shown as TW × MRh. Note that the end surfaces on the + Y side (ABS side) of the layers 23 to 28 are determined by a lapping process described later, and are perpendicular to the film surface.
[0104]
Further, in the first embodiment, as shown in FIGS. 5 and 6, the width Bha of the soft magnetic layer 34a and the protective layer 35a in the MR height direction (Y-axis direction; hereinafter simply referred to as “height direction”). The width Bhb in the height direction (Y-axis direction) of the soft magnetic layer 34b and the protective layer 35b is substantially the same as the MR height MRh. As will be described later, since the layers 23 to 28, the layers 34a and 35a, and the layers 34b and 35b are milled at the same time in the height direction, end surfaces on the −Y side of these layers are defined. Since the end surface of each layer is a tapered surface corresponding to each material, the width in the height direction of each layer is slightly different, but it can be said that these widths are substantially the same. In FIG. 6, for the layers 34a and 35a, only the protective layer 35a is shown, and the width in the height direction is shown as Bha. Similarly, in FIG. 6, only the protective layer 35b is shown for the layers 34b and 35b, and the width in the height direction is shown as Bhb.
[0105]
In order to apply a bias magnetic field sufficient to suppress Barkhausen noise to the free layer 27, the width Wa in the track width direction (Z-axis direction) with respect to the width Bha in the height direction (Y-axis direction) of the soft magnetic layer 34a. Ratio (aspect ratio Wa / Bha) and ratio of the width Wb in the track width direction (Z-axis direction) to the width Bhb in the height direction (Y-axis direction) of the soft magnetic layer 34b (aspect ratio Wb / Bhb) (FIG. 6). Reference) is preferably 5 or more. Also, in order to apply a bias magnetic field sufficient to suppress Barkhausen noise to the free layer 27, the coercive force Hc in the free direction (Z-axis direction) of the soft magnetic layers 34a and 34b is 650 [Oe] or more. It is preferable.
[0106]
Further, in the region where the layers 23 to 28, the layers 32a, 33a, 34a, and 35a and the layers 32b, 33b, 34b, 34b, and 35b are not formed, an Al layer is formed between the lower magnetic shield layer 21 and the upper metal layer 29. ₂ O ₃ Or SiO ₂ An insulating layer 30 is formed.
[0107]
In the first embodiment, as shown in FIG. 5, unlike the first and second conventional examples, the interval d2 is smaller than the interval d1. It is more preferable that the distance d2 is smaller than the distance d1 by 3 nm or more. But in this invention, d2 <= d1 may be sufficient and d2> d1 may be sufficient. . The interval d2 is an effective region in the film surface direction that is effectively involved in magnetic detection in the magnetoresistive effect layer (in the first embodiment, a region in which a current flows in a direction substantially perpendicular to the film surface in the magnetoresistive effect layer). The lower magnetic shield layer 21 and the upper magnetic shield layer in the vicinity of both sides of the effective region in the track width direction (Z-axis direction) of the region that does not substantially overlap with the substantially entire region of the magnetoresistive effect layer) It is an interval between 31. The interval d1 is an interval between the lower magnetic shield layer 21 and the upper magnetic shield layer 31 in a region substantially overlapping with the effective region.
[0108]
Further, as shown in FIG. 5, the lower magnetic shield layer 21 is formed flat without any step at any location, and substantially overlaps the effective region from the region that substantially overlaps the effective region. It has substantially the same height (the height in the X-axis direction) over the region that should not be.
[0109]
As shown in FIGS. 2 and 3, the inductive magnetic transducer element 3 is composed of the upper magnetic shield layer 31, the upper magnetic layer 36, the coil layer 37, and alumina that are also used as the lower magnetic layer for the element 3. The light gap layer 38, the insulating layer 39 made of a thermosetting photoresist (for example, organic resin such as novolac resin), the protective layer 40 made of alumina, and the like are included. As a material of the upper magnetic layer 36, for example, NiFe or FeN is used. The tip portions of the upper electrode 31 and the upper magnetic layer 36 that are also used as the lower magnetic layer are a lower pole portion 31a and an upper pole portion 36a that face each other with a light gap layer 38 such as a minute thickness of alumina, Information is written to the magnetic recording medium in the lower pole portion 31a and the upper pole portion 36a. The upper magnetic shield layer 31 and the upper magnetic layer 36, which are also used as the lower magnetic layer, complete the magnetic circuit at the coupling portion 41 whose yoke portion is opposite to the lower pole portion 31a and the upper pole portion 36a. Are connected to each other. A coil layer 37 is formed inside the insulating layer 39 so as to spiral around the coupling portion 41 of the yoke portion. Both ends of the coil layer 37 are electrically connected to the bonding pads 5c and 5d described above. The number of turns and the number of layers of the coil layer 37 are arbitrary. Further, the structure of the inductive magnetic transducer 3 may be arbitrary. The upper electrode 31 is made of Al to separate the roles of the lower magnetic layer of the inductive magnetic transducer 3 and the upper magnetic shield layer of the TMR element 2. ₂ O ₃ , SiO ₂ Alternatively, the insulating layer may be divided into two layers.
[0110]
Next, an example of a method for manufacturing a magnetic head according to the present embodiment will be described.
[0111]
First, a wafer process is performed. That is, Al to be the base 15 ₂ O ₃ -Prepare a wafer 101 made of TiC or SiC, and form each of the above-described layers in the formation area of a large number of matrix-shaped magnetic heads on the wafer 101 so as to have the above-described structure by using a thin film forming technique or the like. .
[0112]
The outline of the wafer process will be described with reference to FIGS. 7 to 10 are diagrams schematically showing each process constituting the wafer process, and FIGS. 7A, 8A, 9A, and 10A are schematic plan views, respectively. It is. 7B is a schematic sectional view taken along line B-C in FIG. 7A, FIG. 8B is a schematic sectional view taken along line B-C in FIG. 8A, and FIG. (B) is a schematic cross-sectional view along the line D-E in FIG. 9A, FIG. 10B is a schematic cross-sectional view along the line B-C in FIG. 10A, and FIG. ) Is a schematic cross-sectional view along the line D-E in FIG. In FIG. 8A, TW indicates the track width defined by the TMR element 2.
[0113]
In the wafer process, first, the underlayer 16, the lower magnetic shield layer 21, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are sequentially formed on the wafer 101. Laminate (FIG. 7). At this time, the lower magnetic shield layer 21 is formed by, for example, a plating method, and the other layers are formed by, for example, a sputtering method.
[0114]
Next, the lower metal layer 23, the pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, and the upper metal layer 28 are partially removed and patterned by first ion milling. Next, insulating layers 32a and 32b, base layers 33a and 33b, soft magnetic layers 34a and 34b, and protective layers 35a and 35b are sequentially formed on the removed portion by a lift-off method (FIG. 8). Note that the region where the resist mask used in the first ion milling is formed is a region excluding the regions of the protective layers 35a and 35b in FIG.
[0115]
Next, by the second ion milling, the lower metal layer 23, leaving a band-shaped portion having a necessary width (width in the Y-axis direction) in the height direction of the TMR element 2 and extending in the Z-axis direction by a predetermined length, The pinned layer 24, the pinned layer 25, the tunnel barrier layer 26, the free layer 27, the upper metal layer 28, the soft magnetic layers 34a and 34b, and the protective layers 35a and 35b are partially removed and patterned. The insulating layers 32a and 32b and the base layers 33a and 33b may also be removed by the second ion milling. Next, an insulating film 30 is formed on the removed portion by a lift-off method (FIG. 9). Note that the region where the resist mask used in the second ion milling is formed is the region of the protective layers 28, 35a, and 35b in FIG.
[0116]
In FIG. 9A, the outer shapes of the protective films 35a and 35b before the second ion milling are indicated by imaginary lines. In this regard, compare FIG. 9 (a) with FIG. 8 (a). In this manufacturing method, the thickness, material, and the like of the protective layers 35a, 35b are completely removed by the second ion milling in the soft magnetic layers 34a, 34b and the protective layers 35a, 35b in the region where the resist mask is not formed. It is determined to be. Therefore, the protective layers 35a and 35b are relatively thin.
[0117]
Thereafter, the upper metal layer 29 is formed by sputtering or the like, and further the magnetic shield layer 31 is formed by plating or the like (FIG. 10).
[0118]
Finally, the gap layer 38, the coil layer 37, the insulating layer 39, the upper magnetic layer 36, and the protective film 40 are formed, and further the electrodes 5a to 5d and the like are formed. Thereby, the wafer process is completed.
[0119]
Next, the magnetic head is completed through a known process for the wafer after the wafer process is completed. Briefly, each bar (bar-shaped magnetic head assembly) in which a plurality of magnetic head portions are arranged in a line on a substrate is cut out from the wafer. Next, lapping (polishing) is performed on the ABS side in order to set the throat height, MR height, and the like for the bar. Next, the protective film 4 is formed on the ABS side, and the rails 11 and 12 are further formed by etching or the like. Finally, the bar is separated into individual magnetic heads by cutting. Thereby, the magnetic head according to the present embodiment is completed.
[0120]
According to the present embodiment, as shown in FIG. 5, since the distance d2 is smaller than the distance d1, the upper magnetic shield is compared with the first conventional example (see FIG. 13) where d2> d1. The layer 31 approaches the position directly beside the magnetoresistive effect layer on both sides of the magnetoresistive effect layer in the track width direction (Z-axis direction). Therefore, the recording density in the linear direction can be increased without causing a result that the read gap is widened. Also, since the upper magnetic shield layer 31 approaches the position directly beside the magnetoresistive effect layer on both sides of the magnetoresistive effect layer in the track width direction, side reading is reduced, thereby increasing the recording density in the track width direction. be able to. Further, it has been proved by an experiment described later that even if the distance d2 is smaller than the distance d1, electrical insulation between the magnetic shield layers can be secured.
[0121]
In addition, according to the present embodiment, the lower magnetic shield layer 21 is formed flat without having a step or the like at any location, and therefore it is not necessary to form a step or the like, so that the manufacture is easy. It is preferable.
[0122]
Furthermore, according to the present embodiment, the pair of longitudinal bias layers includes the soft magnetic layers 34a and 34b, respectively, but does not include the antiferromagnetic layer exchange-coupled to the soft magnetic layers 34a and 34b. Compared to the case where the exchange bias method using the antiferromagnetic layers 134a ′ and 134b ′ that are exchange-coupled to the soft magnetic layers 134a and 134b in addition to the soft magnetic layers 134a and 134b as in the conventional example, the antiferromagnetic layers 134a ′, The distance d2 between the magnetic shield layers 21 and 31 in the vicinity of both sides in the track width direction of the effective region out of the region that does not substantially overlap the effective region of the magnetoresistive effect layer by the thickness of 134b ′ The distance d1 between the magnetic shield layers 21 and 31 in the region substantially overlapping the region can be further reduced. Therefore, according to the present embodiment, the recording density in the line direction and the track width direction can be further increased. Also, the side reading is reduced by the soft magnetic layers 34a and 34b, and the recording density in the track width direction can be further increased. These advantages can be obtained even when d2 ≧ d1 or d2 <d1.
[0123]
Even if the longitudinal bias layer does not include an antiferromagnetic layer, by appropriately setting the shapes of the soft magnetic layers 34a and 34b, a bias magnetic field sufficient to suppress Barkhausen noise can be applied to the free layer. This was confirmed by an experiment described later.
[0124]
In addition, according to the present embodiment, since each longitudinal bias layer does not use an antiferromagnetic layer, and the Curie temperature of typical soft magnetic materials (NiFe, CoFe, etc.) is 500 ° C., At about 200 ° C., the temperature characteristics are also good.
[0125]
Furthermore, according to the present embodiment, as shown in FIG. 6, Bha = Bhb = MRh and Narrow type is adopted, so that the protection is improved as compared with the second conventional example adopting Wide type. The thickness of the films 35a and 35b can be reduced. For this reason, the space between the magnetic shield layers 21 and 31 in the vicinity of both sides in the track width direction of the effective region in the region that does not substantially overlap the effective region of the magnetoresistive effect layer substantially overlaps the effective region. The distance between the magnetic shield layers 21 and 31 in the region can be further reduced. Therefore, according to the present embodiment, the recording density in the line direction and the track width direction can be further increased.
[0126]
[Second Embodiment]
[0127]
FIG. 11 is a schematic perspective view showing the configuration of the main part of the magnetic disk apparatus according to the second embodiment of the present invention.
[0128]
The magnetic disk device according to the second embodiment includes a magnetic disk 71 rotatably provided around an axis 70, a magnetic head 72 that records and reproduces information on the magnetic disk 71, and a magnetic head 72. And an assembly carriage device 73 for positioning on the track of the magnetic disk 71.
[0129]
The assembly carriage device 73 is mainly composed of a carriage 75 that can be rotated about a shaft 74 and an actuator 76 that is, for example, a voice coil motor (VCM) that drives the carriage 75 to rotate.
[0130]
A base portion of a plurality of drive arms 77 stacked in the direction of the shaft 74 is attached to the carriage 75, and a head suspension assembly 78 on which a magnetic head 72 is mounted is fixed to the front end portion of each drive arm 77. Yes. Each head suspension assembly 78 is provided at the tip of the drive arm 77 so that the magnetic head 72 at the tip of the head suspension assembly 78 faces the surface of each magnetic disk 71.
[0131]
In the second embodiment, the magnetic head according to the first embodiment described above is mounted as the magnetic head 72. Therefore, according to the second embodiment, advantages such as an increase in recording density can be obtained.
[0132]
【Example】
A sample without patterning shown in FIG. 26 and a sample with patterning shown in FIG. 27 were produced. FIG. 26 (a) is a schematic plan view schematically showing a sample without patterning, and FIG. 26 (b) is an RR ′ arrow view in FIG. 26 (a). FIG. 27 (a) is a schematic plan view schematically showing a sample with patterning, and FIG. 27 (b) is an SS ′ arrow view in FIG. 27 (a).
[0133]
A sample without patterning shown in FIG. 26 has a Ta layer 302 having a thickness of 5 nm (corresponding to the underlayers 33a and 33b in FIG. 5) and a NiFe layer 303 having a thickness of 25 nm (a soft layer in FIG. 5) on the silicon substrate 301. Magnetic layer 34a, 34b) and 30 nm thick Ta layer 304 (corresponding to protective layers 35a, 35b in FIG. 5) are sequentially stacked from the substrate 301 side, and each layer 302-304 is patterned. Absent. The sample with patterning shown in FIG. 27 forms a mask pattern having a rectangular shape of 0.5 μm × 0.1 μm when viewed from the X-axis direction by electron beam lithography with respect to the sample shown in FIG. Then, after patterning the layers 302 to 304 by ion milling using this mask pattern, the mask pattern is removed. Therefore, in FIG. 27, the layers 302 to 304 are substantially 0.5 μm (corresponding to Wa and Wb in FIG. 6) × 0.1 μm (corresponding to Bha and Bhb in FIG. 6) rectangular shape (its aspect) The ratio was patterned to 5).
[0134]
Then, the MH curve of each sample shown in FIGS. 26 and 27 was evaluated by a VSM (Vibrating Sample Magnetometer). The results are shown in FIGS. 28 and 29, respectively. In these samples, the Z-axis direction in FIGS. 26 and 27 is the direction of the easy axis of magnetization of the NiFe layer 303 (free direction).
[0135]
In the sample without patterning shown in FIG. 26, the coercive force Hc in the free direction is about 8 [Oe], whereas in the sample with patterning shown in FIG. 27, the coercive force Hc in the free direction is about 650 [Oe]. is there. That is, the fact that the coercive force Hc in the free direction of the patterned sample is large means that the patterned soft magnetic layer can potentially give a longitudinal bias to the free layer as shown in FIG. Show.
[0136]
It is known that the coercive force Hc resulting from the shape anisotropy of the soft magnetic layer increases as the aspect ratio increases and the film thickness increases (the magnetic film thickness Bst increases). (FIG. 2, 3 of nonpatent literature 1).
[0137]
Therefore, it can be seen that when a soft magnetic layer having an aspect ratio of 5 or more is used as the longitudinal bias layer, a sufficient bias magnetic field can be applied to the free layer.
[0138]
Further, as Sample 1, a magnetic head corresponding to the first embodiment was manufactured by the corresponding manufacturing method described above with the structure of each main layer as shown in Table 1 below. As Sample 2, a magnetic head (Narrow type, exchange bias method) corresponding to the first conventional example was manufactured by the corresponding manufacturing method described above, with the constitution of each main layer shown in Table 2 below. . As a sample 3, a magnetic head (Wide type, hard magnetic bias method) corresponding to the second conventional example is manufactured by the corresponding manufacturing method described above with the main layers as shown in Table 3 below. did.
[0139]
[Table 1]

[0140]
[Table 2]

[0141]
[Table 3]

[0142]
Sample 1 corresponds to an example of the present invention, and samples 2 and 3 correspond to comparative examples, respectively. From the layer configurations shown in Tables 1 to 3, as shown in Tables 1 to 3, the sample 1 is d2-d1 = -3 nm, the sample 2 is d2-d1 = + 4 nm, and the sample 3 is d2-d1 = + 32 nm. .
[0143]
In Samples 1 and 2, TW = 0.1 μm, MRh = Bha = Bhb = 0.1 μm, and Wa = Wb = 0.5 μm. In sample 3, TW = 0.1 μm.
[0144]
Both samples 1 to 3 were cut into a bar state after completion of the wafer process, and the TMR element 2 was directly polished with diamond particles as a lapping process to define the MR height MRh as 0.1 μm. Samples 1 to 3 were each manufactured as a floating magnetic head with diamond-like carbon (DLC) 3 nm as the head protective film 4, and the effective track width and Barkhausen noise (BHN) generation rate were measured. The results are shown in Table 4.
[0145]
[Table 4]

[0146]
Samples 1 and 3 corresponding to the comparative example (heads using a longitudinal bias layer composed only of a soft magnetic layer having a large coercive force Hc due to shape anisotropy) corresponding to the example of the present invention are also included in Samples 2 and 3 corresponding to the comparative example (conventional) It can be seen that Barkhausen noise can be suppressed to the same extent as a head using a vertical bias layer. In sample 1, d2-d1 is smaller than in samples 2 and 3, so that the side shield effect is increased and the effective track width can be narrowed.
[0147]
Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments.
[0148]
For example, the embodiment described above is an example applied to a TMR head, but the present invention is applicable to a head having a magnetoresistive effect element having a CPP structure such as a CPP-GMR head, a GMR head having a CIP structure, or the like. Can be applied.
[0149]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a magnetic head capable of increasing the recording density in the linear direction and the track width direction, and a head suspension assembly and a magnetic disk apparatus using the magnetic head.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view schematically showing a magnetic head according to a first embodiment of the invention.
2 is an enlarged cross-sectional view schematically showing portions of a TMR element and an inductive magnetic conversion element of the magnetic head shown in FIG.
FIG. 3 is a schematic view taken along the line AA ′ in FIG. 2;
4 is an enlarged view in which the vicinity of the TMR element in FIG. 2 is further enlarged. FIG.
FIG. 5 is an enlarged view in which the vicinity of the TMR element in FIG. 3 is further enlarged.
6 is a schematic plan view schematically showing the positional relationship of layers below a predetermined layer in the magnetic head shown in FIG. 1 as viewed from the X-axis direction.
7 is a view schematically showing one process constituting a wafer process in the method of manufacturing the magnetic head shown in FIG. 1. FIG.
8 is a view schematically showing another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 1. FIG.
9 is a view schematically showing still another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 1. FIG.
10 is a diagram schematically showing still another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 1. FIG.
FIG. 11 is a schematic perspective view showing a configuration of a main part of a magnetic disk device according to a second embodiment of the present invention.
FIG. 12 is a cross-sectional view schematically showing the vicinity of a TMR element of a magnetic head of a first conventional example.
13 is a schematic view taken along the line FF ′ in FIG.
14 is a schematic plan view schematically showing a positional relationship of layers below a predetermined layer in the magnetic head shown in FIG. 12 as viewed from the X-axis direction.
15 is a view schematically showing one process constituting a wafer process in the method of manufacturing the magnetic head shown in FIG.
FIG. 16 is a diagram schematically showing another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 12;
17 is a view schematically showing still another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 12. FIG.
18 is a diagram schematically showing still another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 12. FIG.
FIG. 19 is a cross-sectional view schematically showing the vicinity of a TMR element of a magnetic head of a second conventional example.
20 is a schematic view taken along line LL ′ in FIG.
21 is a schematic plan view schematically showing the positional relationship of layers below a predetermined layer in the magnetic head shown in FIG. 19 as viewed from the X-axis direction.
22 is a view schematically showing one process constituting a wafer process in the method of manufacturing the magnetic head shown in FIG.
FIG. 23 is a diagram schematically showing another process constituting the wafer process in the magnetic head manufacturing method shown in FIG. 19;
24 is a diagram schematically showing still another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 19. FIG.
25 is a view schematically showing still another process constituting the wafer process in the method of manufacturing the magnetic head shown in FIG. 19. FIG.
FIG. 26 is a diagram schematically showing a sample without patterning related to a soft magnetic layer.
FIG. 27 is a diagram schematically showing a sample with patterning related to a soft magnetic layer.
FIG. 28 is a diagram showing an MH curve of the sample shown in FIG.
29 is a diagram showing an MH curve of the sample shown in FIG. 27. FIG.
[Explanation of symbols]
1 Slider
2 TMR element
3 Inductive magnetic transducer
21 Lower magnetic shield layer
23 Lower metal layer
24 pin layer
25 pinned layers
26 Tunnel barrier layer
27 Free layer
28 Upper metal layer (cap layer)
29 Upper metal layer
30 Insulating layer
31 Upper magnetic shield layer
32a, 32b insulation layer
33a, 33b Underlayer
34a, 34b Soft magnetic layer (longitudinal bias layer)
35a, 35b protective layer

Claims (10)

A base, first and second magnetic shield layers formed on one side of the base, and the first magnetic shield layer and the second magnetic shield layer. A magnetoresistive layer including a free layer, and a pair of bias layers for applying a bias magnetic field mainly in the track width direction to the free layer,
The pair of bias layers are disposed on both sides of the magnetoresistive layer in the track width direction between the first magnetic shield layer and the second magnetic shield layer,
Each of the bias layers includes a soft magnetic layer but does not include an antiferromagnetic layer exchange-coupled to the soft magnetic layer,
Wherein the ratio of the track width direction of the width to the MR height direction of the width of the soft magnetic layer of each bias layer state, and are 5 or more,
MR height is 100 nm or less,
The magnetic head according to claim 1 , wherein the width in the MR height direction of the soft magnetic layer of each bias layer is substantially the same as the MR height .   Among the regions in which the distance between the first magnetic shield layer and the second magnetic shield layer does not substantially overlap with the effective region in the film plane direction that is effectively involved in magnetic detection in the magnetoresistive effect layer 2. The magnetic head according to claim 1, wherein at least a region near both sides of the effective region in the track width direction is smaller than a region substantially overlapping with the effective region.   Of the first and second magnetic shield layers, the base-side magnetic shield layer has substantially the same height from a region that substantially overlaps the effective region to a region that does not substantially overlap the effective region. The magnetic head according to claim 2, comprising:   4. The magnetic head according to claim 1, wherein the soft magnetic layer has a coercive force in the track width direction of 650 [Oe] or more.   The width in the MR height direction of each of the bias layers is substantially the same as the width in the MR height direction of an effective region in the film surface direction that is effectively involved in magnetic detection in the magnetoresistive effect layer. The magnetic head according to any one of 1 to 4.   2. The effective region in the film surface direction that is effectively involved in magnetism detection in the magnetoresistive effect layer is a region in which current flows in a direction substantially perpendicular to the film surface in the magnetoresistive effect layer. The magnetic head according to any one of 1 to 5.   The magnetoresistive layer includes a tunnel barrier layer formed on one surface side of the free layer, a pinned layer formed on a side of the tunnel barrier layer opposite to the free layer, and the pinned layer The magnetic head according to claim 6, further comprising: a pinned layer formed on a side opposite to the tunnel barrier layer.   8. A magnetic head according to claim 1, wherein the soft magnetic layer is made of NiFe or CoFe.   9. A magnetic head according to claim 1, comprising: a magnetic head; and a suspension that is mounted near the tip of the magnetic head and supports the magnetic head, wherein the magnetic head is the magnetic head according to claim 1. Head suspension assembly.   10. A magnetic disk drive comprising: the head suspension assembly according to claim 9; an arm portion that supports the assembly; and an actuator that moves the arm portion to position the magnetic head.

Images