JP3083090B2 - Magnetoresistive sensor - Google Patents
Magnetoresistive sensorInfo
- Publication number
- JP3083090B2 JP3083090B2 JP10302263A JP30226398A JP3083090B2 JP 3083090 B2 JP3083090 B2 JP 3083090B2 JP 10302263 A JP10302263 A JP 10302263A JP 30226398 A JP30226398 A JP 30226398A JP 3083090 B2 JP3083090 B2 JP 3083090B2
- Authority
- JP
- Japan
- Prior art keywords
- layer
- ferromagnetic layer
- magnetoresistive sensor
- ferromagnetic
- film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 230000005294 ferromagnetic effect Effects 0.000 claims description 79
- 230000005291 magnetic effect Effects 0.000 claims description 58
- 230000005290 antiferromagnetic effect Effects 0.000 claims description 36
- 229910000480 nickel oxide Inorganic materials 0.000 claims description 25
- 230000005415 magnetization Effects 0.000 claims description 24
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 17
- 125000006850 spacer group Chemical group 0.000 claims description 17
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims description 11
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 claims description 8
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 7
- 229910045601 alloy Inorganic materials 0.000 claims description 4
- 239000000956 alloy Substances 0.000 claims description 4
- 230000004907 flux Effects 0.000 claims description 4
- 238000000034 method Methods 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 2
- 229910052742 iron Inorganic materials 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 239000010410 layer Substances 0.000 description 164
- 230000035945 sensitivity Effects 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 229910000859 α-Fe Inorganic materials 0.000 description 6
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 230000001939 inductive effect Effects 0.000 description 3
- 239000002356 single layer Substances 0.000 description 3
- 229910001030 Iron–nickel alloy Inorganic materials 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 239000002885 antiferromagnetic material Substances 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000011241 protective layer Substances 0.000 description 2
- 229910020707 Co—Pt Inorganic materials 0.000 description 1
- 229910003271 Ni-Fe Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 238000000992 sputter etching Methods 0.000 description 1
Landscapes
- Magnetic Heads (AREA)
- Hall/Mr Elements (AREA)
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、磁気的に記録され
た情報を再生する磁気抵抗センサ、特に、磁気ディスク
装置、磁気テープ装置に搭載される磁気ヘッドの再生素
子に関するものである。The present invention relates to a magnetoresistive sensor for reproducing magnetically recorded information, and more particularly to a reproducing element of a magnetic head mounted on a magnetic disk device and a magnetic tape device.
【０００２】[0002]
【従来の技術】磁気記録再生装置、特に、磁気ディスク
装置における記録密度の向上は著しく、磁気ディスクの
キー・デバイスである再生用磁気ヘッドには高感度化が
要求されている。近年では、再生素子として磁気抵抗セ
ンサを利用したＭＲヘッドが用いられている。2. Description of the Related Art The recording density of a magnetic recording / reproducing apparatus, especially a magnetic disk apparatus, has been remarkably improved, and a high sensitivity is required for a reproducing magnetic head which is a key device of a magnetic disk. In recent years, an MR head using a magnetoresistive sensor has been used as a reproducing element.
【０００３】ＭＲヘッドは、従来のいわゆる誘導型ヘッ
ドに比べて、高い信号／ノイズ比（Ｓ／Ｎ比）が得られ
るのが特徴である。[0003] The MR head is characterized in that a higher signal / noise ratio (S / N ratio) can be obtained as compared with a conventional so-called inductive head.
【０００４】現在のＭＲヘッドは、異方性磁気抵抗効果
（ＡＭＲ効果）により、磁気ディスク上の磁気的な信号
を電気信号に変換しているが、ＡＭＲ効果をもってして
もトラック幅、ビット長の狭小化が進行すると感度不足
になり、数Ｇｂ／ｉｎ2程度が限界と考えられている。
これ以上の記録密度に対応するためには、より高感度の
磁気抵抗センサが必要であり、巨大磁気抵抗効果（ＧＭ
Ｒ効果）を用いたＭＲヘッドが注目されている。In the current MR head, a magnetic signal on a magnetic disk is converted into an electric signal by an anisotropic magnetoresistance effect (AMR effect). The sensitivity becomes insufficient as the narrowing progresses, and it is considered that the limit is about several Gb / in 2 .
In order to cope with higher recording densities, a more sensitive magnetoresistive sensor is required, and a giant magnetoresistive effect (GM
An MR head using the (R effect) has attracted attention.
【０００５】ＧＭＲ効果を用いたヘッドの一つとして、
特開平４−３５８３１０号公報には、スピンバルブ構造
と呼ばれる構造のものが示されている。これは、反強磁
性層によって磁化が特定の方向に固定された固定層と、
薄い非磁性導電層を介して固定層に積層された自由層で
構成されており、固定層の磁化と自由層の磁化の相対的
な角度によって、電気抵抗が変化するものである。As one of the heads using the GMR effect,
Japanese Patent Application Laid-Open No. 4-358310 discloses a structure called a spin valve structure. This is a fixed layer in which the magnetization is fixed in a specific direction by an antiferromagnetic layer,
It is composed of a free layer laminated on a fixed layer via a thin non-magnetic conductive layer, and its electric resistance changes depending on the relative angle between the magnetization of the fixed layer and the magnetization of the free layer.
【０００６】上記公報では、反強磁性層としてＦｅ50Ｍ
ｎ50を用いているが、Ｆｅ50Ｍｎ50は耐食性が悪く、導
電性であるためにセンス電流がＦｅ50Ｍｎ50にも分流し
て出力が減少すると云う問題がある。In the above publication, Fe 50 M is used as the antiferromagnetic layer.
Although n 50 is used, Fe 50 Mn 50 has poor corrosion resistance and has a problem that the sense current is shunted to Fe 50 Mn 50 and the output is reduced because of its conductivity.
【０００７】このため、特開平５−３４７０１３号公報
にはＦｅ50Ｍｎ50の替わりに酸化ニッケル（ＮｉＯ）を
用いたスピンバルブセンサが、また、アイイーイーイー
トランザクション オン マグネティクス ３４巻，
４号 ９５４〜９５６頁には酸化ニッケル（ＮｉＯ）と
酸化鉄（α−Ｆｅ2Ｏ3）の二層反強磁性体を用いたスピ
ンバルブセンサが記載されている。For this reason, Japanese Patent Application Laid-Open No. 5-347003 discloses a spin valve sensor using nickel oxide (NiO) instead of Fe 50 Mn 50 , and IEE Transaction on Magnetics, Vol.
No. 4, pages 954 to 956, a spin valve sensor using a two-layer antiferromagnetic material of nickel oxide (NiO) and iron oxide (α-Fe 2 O 3 ) is described.
【０００８】反強磁性層として酸化ニッケル（ＮｉＯ）
を用いた場合には、固定層である強磁性層との交換結合
特性は、図６に示すように、一方向異方性磁界（Ｈｕ
ａ）よりも固定層の保磁力（Ｈｃｐ）の方が大きく、何
らかの大きな外部磁界が加わったときには、ゼロ磁界近
傍における磁化の状態が変わり感度が低下してしまう。[0008] Nickel oxide (NiO) as an antiferromagnetic layer
In the case where is used, as shown in FIG. 6, the exchange coupling characteristic with the ferromagnetic layer as the fixed layer is a unidirectional anisotropic magnetic field (Hu).
The coercive force (Hcp) of the fixed layer is higher than that of a), and when any large external magnetic field is applied, the magnetization state near the zero magnetic field changes and the sensitivity decreases.
【０００９】これを改善する方法として、特開平７−１
６９０２６号公報には、固定層を強磁性層／非磁性スペ
ーサ層／強磁性層と云う積層構造にすることが提案され
ており、さらに、特開平９−１６９２０号公報には酸化
ニッケル（Ｎｉ1-xＣｏxＯ）などの反強磁性層の上に、
強磁性層／非磁性スペーサ層／強磁性層を積層した構造
が開示されている。As a method for improving this, Japanese Patent Application Laid-Open No. 7-1
The 69026 discloses the fixed layer and it is proposed to the laminate structure referred to as a ferromagnetic layer / a nonmagnetic spacer layer / ferromagnetic layer, further, Japanese Patent Laid-Open No. 9-16920 nickel oxide (Ni 1 -x Co x O)
A structure in which a ferromagnetic layer / a nonmagnetic spacer layer / a ferromagnetic layer is stacked is disclosed.
【００１０】[0010]
【発明が解決しようとする課題】特開平５−３４７０１
３号公報では、酸化ニッケル（ＮｉＯ）を用いたスピン
バルブセンサが、アイイーイーイー トランザクション
オン マグネティクス３４巻，４号 ９５４〜９５６
頁には、酸化ニッケル（ＮｉＯ）と酸化鉄（α−Ｆｅ2
Ｏ3）の二層反強磁性体を用いたスピンバルブセンサが
示されているが、固定層との交換結合特性、特に、Ｈｕ
ａが十分大きいとは云えず、外部磁界に対する安定性が
懸念される。Problems to be Solved by the Invention Japanese Patent Laid-Open No. 5-34701
In Japanese Patent Publication No. 3 (1993), a spin valve sensor using nickel oxide (NiO) is disclosed in IEE Transaction on Magnetics Vol. 34, No. 4, 954-956.
The page shows nickel oxide (NiO) and iron oxide (α-Fe 2
Although a spin valve sensor using a two-layer antiferromagnetic material of O 3 ) is shown, exchange coupling characteristics with a fixed layer, particularly Hu
a cannot be said to be sufficiently large, and there is a concern about stability against an external magnetic field.
【００１１】特開平９−１６９２０号公報では、酸化ニ
ッケル（Ｎｉ1-xＣｏxＯ）などの反強磁性層の上に、強
磁性層／非磁性スペーサ層／強磁性層からなる固定層を
積層することにより、見かけ上Ｈｕａが大きくなり、外
部磁界に対する安定性が向上することが示されている。In Japanese Patent Application Laid-Open No. Hei 9-16920, a fixed layer composed of a ferromagnetic layer / a nonmagnetic spacer layer / a ferromagnetic layer is provided on an antiferromagnetic layer such as nickel oxide (Ni 1-x Co x O). It is shown that the lamination increases the apparent Hua and improves the stability against an external magnetic field.
【００１２】この構造では、酸化ニッケル反強磁性層
と、これに接する強磁性層との間の交換結合特性が、外
部磁界に対する安定性を決定する要因の一つになってい
る。酸化ニッケルと強磁性層の交換結合特性は、Ｈｕａ
よりもＨｃｐの方が大きく、ある程度の大きさの外部磁
界が作用した場合には、磁界ゼロ近傍で磁化状態が変わ
ってしまう可能性がある。この問題は、固定層を強磁性
層／非磁性スペーサ層／強磁性層にしても、磁界ゼロ近
傍での磁化状態が変化しない外部磁界の大きさが大きく
なるだけで、本質的には解決することはできない。In this structure, the exchange coupling characteristic between the nickel oxide antiferromagnetic layer and the ferromagnetic layer in contact with it is one of the factors that determine the stability to an external magnetic field. The exchange coupling characteristic between nickel oxide and the ferromagnetic layer is Hua.
Hcp is larger than Hcp, and when an external magnetic field of a certain magnitude acts, the magnetization state may change near zero magnetic field. This problem is essentially solved even if the pinned layer is made of a ferromagnetic layer / non-magnetic spacer layer / ferromagnetic layer, only the magnitude of the external magnetic field whose magnetization state does not change near zero magnetic field increases. It is not possible.
【００１３】本発明の目的は、外部磁界に対して安定
で、高感度、高出力を有する磁気抵抗センサを提供する
ことにある。An object of the present invention is to provide a magnetoresistive sensor which is stable to an external magnetic field, has high sensitivity, and has high output.
【００１４】[0014]
【課題を解決するための手段】上記目的を達成する本発
明の要旨は次のとおりである。The gist of the present invention to achieve the above object is as follows.
【００１５】〔１〕 非磁性導電層を介して第１の強磁
性層と第２の強磁性層が積層され、非磁性スペーサ層を
介して前記第２の強磁性層と第３の強磁性層が積層され
ており、前記第２の強磁性層と前記第３の強磁性層が非
磁性スペーサ層を介して反強磁性的に結合しており、前
記第１の強磁性層の磁化の方向が外部磁界ゼロのときに
前記第２の強磁性層の磁化の方向とある角度を成し、前
記第１の強磁性層の磁化の方向と前記第２の強磁性層の
磁化の方向の相対的な角度が変わることによって電気抵
抗が変化する磁気抵抗センサ膜と、前記磁気抵抗センサ
膜に信号検出電流を流すための電極と、前記磁気抵抗セ
ンサ膜の電気抵抗変化を検知する手段を有する磁気抵抗
センサにおいて、前記第３の強磁性層が酸化鉄ＦｅxＯ
（但し、０.５７≦ｘ≦０.７０）からなる第１の反強磁
性層の上に積層されており、前記第１の反強磁性層が酸
化ニッケル（Ｎｉ1-xＣｏx）Ｏ（但し、０≦ｘ≦０.
５）からなる第２の反強磁性層の上に積層されており、
前記第３の強磁性層の飽和磁束密度と膜厚の積が、前記
第２の強磁性層の飽和磁束密度と膜厚の積よりも小さい
ことを特徴とする磁気抵抗センサ。[1] A first ferromagnetic layer and a second ferromagnetic layer are stacked with a nonmagnetic conductive layer interposed therebetween, and the second ferromagnetic layer and the third ferromagnetic layer are stacked with a nonmagnetic spacer layer interposed therebetween. Layers are stacked, the second ferromagnetic layer and the third ferromagnetic layer are antiferromagnetically coupled via a non-magnetic spacer layer, and the magnetization of the first ferromagnetic layer is The direction forms an angle with the direction of magnetization of the second ferromagnetic layer when the external magnetic field is zero, and the direction of the magnetization of the first ferromagnetic layer and the direction of magnetization of the second ferromagnetic layer are different. A magnetoresistive sensor film whose electric resistance changes due to a change in relative angle; an electrode for flowing a signal detection current through the magnetoresistive sensor film; and a means for detecting a change in electric resistance of the magnetoresistive sensor film In the magnetoresistive sensor, the third ferromagnetic layer is formed of iron oxide Fe x O
(Where 0.57 ≦ x ≦ 0.70), wherein the first antiferromagnetic layer is formed of nickel oxide (Ni 1-x Co x ) O. (However, 0 ≦ x ≦ 0.
5) being laminated on the second antiferromagnetic layer comprising
The product of the saturation magnetic flux density and the film thickness of the third ferromagnetic layer is
A magnetoresistive sensor characterized by being smaller than the product of the saturation magnetic flux density and the thickness of the second ferromagnetic layer .
【００１６】〔２〕 前記第２の反強磁性層の膜厚が３
０ｎｍ以上である前記の磁気抵抗センサ。[2] The thickness of the second antiferromagnetic layer is 3
The aforementioned magnetoresistive sensor having a thickness of 0 nm or more.
【００１７】〔３〕 前記第１の反強磁性層の膜厚が
０.５〜１０ｎｍである前記の磁気抵抗センサ。[3] The magnetoresistive sensor as described above, wherein the thickness of the first antiferromagnetic layer is 0.5 to 10 nm.
【００１８】〔４〕 前記第３の強磁性層がＦｅ，Ｃ
ｏ，Ｎｉおよびそれらの合金である前記の磁気抵抗セン
サ。[4] The third ferromagnetic layer is made of Fe, C
The magnetoresistive sensor as described above, which is o, Ni or an alloy thereof.
【００１９】〔５〕 前記第３の強磁性層がＣｏ1-xＦ
ｅx（但し、０＜ｘ≦０.２）である前記〔４〕に記載の
磁気抵抗センサ。[5] The third ferromagnetic layer is made of Co 1-x F
e x (where, 0 <x ≦ 0.2) magnetoresistive sensor according to the a [4].
【００２０】[0020]
【発明の実施の形態】以下、本発明による実施の形態に
ついて、図面を用いて説明する。まず、本発明の磁気抵
抗センサ膜の構成を図１に示す。Embodiments of the present invention will be described below with reference to the drawings. First, the configuration of the magnetoresistive sensor film of the present invention is shown in FIG.
【００２１】Ｓｉ基板１０の上に、第２の反強磁性層１
１１としてＮｉＯ５０ｎｍ、第１の反強磁性層１１２と
してα−Ｆｅ2Ｏ3２ｎｍを積層して反強磁性層１１を形
成した。その上に第３の強磁性層１２、非磁性スペーサ
層１３としてＲｕ０.８ｎｍ、第２の強磁性層１４，非
磁性導電層１５としてＣｕ２.５ｎｍ、第１の強磁性層
１６としてＣｏ１ｎｍとＮｉＦｅ５ｎｍの２層膜、さら
に保護層１７としてＴａ５ｎｍを順次積層した。On the Si substrate 10, the second antiferromagnetic layer 1
NiO50nm as 11, to form the antiferromagnetic layer 11 by laminating a α-Fe 2 O 3 2nm as the first antiferromagnetic layer 112. On top of this, the third ferromagnetic layer 12, the non-magnetic spacer layer 13 are Ru 0.8 nm, the second ferromagnetic layer 14 and the non-magnetic conductive layer 15 are Cu 2.5 nm, and the first ferromagnetic layer 16 is Co1 nm and NiFe 5 nm. And a protective layer 17 of Ta5 nm was sequentially laminated.
【００２２】なお、第３の強磁性層１２／非磁性スペー
サ層１３／第２の強磁性層１４が固定層に、第１の強磁
性層１６が自由層に相当する。The third ferromagnetic layer 12 / nonmagnetic spacer layer 13 / second ferromagnetic layer 14 corresponds to a fixed layer, and the first ferromagnetic layer 16 corresponds to a free layer.
【００２３】ここで、第３の強磁性層１２、第２の強磁
性層１４にはＣｏ90Ｆｅ10を用い、それぞれの膜厚を
２.５ｎｍと３.０ｎｍとした。なお、第３および第２の
強磁性層の磁化が、それぞれ１０２および１０１の方向
に異方性が誘導されるよう、第１の強磁性層については
１００の方向に誘導されるように、成膜時に基板面とほ
ぼ平行に磁界を印加した。Here, Co 90 Fe 10 was used for the third ferromagnetic layer 12 and the second ferromagnetic layer 14, and their thicknesses were set to 2.5 nm and 3.0 nm, respectively. The magnetizations of the third and second ferromagnetic layers are formed such that anisotropy is induced in directions 102 and 101, respectively, and that the first ferromagnetic layer is induced in direction 100. During the film formation, a magnetic field was applied substantially parallel to the substrate surface.
【００２４】磁気抵抗センサ膜成膜後、１０１に示す方
向に１５ｋＯｅの磁界を印加しながら、２３０℃、３時
間の熱処理を行い、反強磁性層１１と第３の強磁性層１
２との間に一方向異方性を発生させた。この熱処理によ
り、自由層、即ち、第１の強磁性層１６の磁化の方向も
１０１の方向を向く。After forming the magnetoresistive sensor film, a heat treatment is performed at 230 ° C. for 3 hours while applying a magnetic field of 15 kOe in the direction indicated by 101 to obtain the antiferromagnetic layer 11 and the third ferromagnetic layer 1.
A unidirectional anisotropy was generated between the two. By this heat treatment, the direction of magnetization of the free layer, that is, the first ferromagnetic layer 16 is also directed to the direction of 101.
【００２５】上記のように作製した磁気抵抗センサ膜の
磁気抵抗変化曲線を測定した。比較のため、第３の強磁
性層１２／非磁性スペーサ層１３／第２の強磁性層１４
からなる固定層で、反強磁性層１１がＮｉＯ５０ｎｍ単
層で構成されているもの、さらに図２に示すように、固
定層がＣｏ90Ｆｅ10３.０ｎｍからなる第２の強磁性層
１４のみで構成されており、反強磁性層１１が第２の反
強磁性層１１１であるＮｉＯ５０ｎｍと、第１の反強磁
性層１１２であるα−Ｆｅ2Ｏ3２ｎｍの積層膜で構成さ
れているものと、反強磁性層１１がＮｉＯ５０ｎｍのみ
で構成されているものも作製し、特性を比較した。The magnetoresistance change curve of the magnetoresistive sensor film produced as described above was measured. For comparison, the third ferromagnetic layer 12 / nonmagnetic spacer layer 13 / second ferromagnetic layer 14
The antiferromagnetic layer 11 is composed of a single layer of 50 nm of NiO, and as shown in FIG. 2, only the second ferromagnetic layer 14 of which the fixed layer is composed of 3.0 nm of Co 90 Fe 10 The antiferromagnetic layer 11 is composed of a laminated film of 50 nm of NiO as the second antiferromagnetic layer 111 and 2 nm of α-Fe 2 O 3 as the first antiferromagnetic layer 112. A sample and a sample in which the antiferromagnetic layer 11 is composed of only 50 nm of NiO were also prepared, and their characteristics were compared.
【００２６】図３および図４は、固定層が第３の強磁性
層１２／非磁性スペーサ層１３／第２の強磁性層１４か
らなる積層構造で、反強磁性層がそれぞれＮｉＯ５０ｎ
ｍとα−Ｆｅ2Ｏ3２ｎｍの積層膜、および、ＮｉＯ５０
ｎｍ単層である磁気抵抗センサ膜について、±２ｋＯｅ
の磁界を印加して測定した磁気抵抗変化曲線である。FIGS. 3 and 4 show a laminated structure in which the fixed layer is composed of the third ferromagnetic layer 12 / non-magnetic spacer layer 13 / second ferromagnetic layer 14, and the antiferromagnetic layers are each composed of NiO50n.
m and α-Fe 2 O 3 2 nm laminated film and NiO 50
± 2 kOe for a magnetoresistive sensor film that is a single nm
4 is a magnetoresistance change curve measured by applying a magnetic field of FIG.
【００２７】また、図５および図６は、固定層が第２の
強磁性層１４のみからなり、反強磁性層がそれぞれＮｉ
Ｏ５０ｎｍとα−Ｆｅ2Ｏ3２ｎｍの積層膜、および、Ｎ
ｉＯ５０ｎｍ単層である磁気抵抗センサ膜について、±
１.５ｋＯｅの磁界を印加して測定した磁気抵抗変化曲
線である。FIGS. 5 and 6 show that the fixed layer is composed of only the second ferromagnetic layer 14 and the antiferromagnetic layer is composed of Ni.
O 50 nm and α-Fe 2 O 3 2 nm laminated film, and N
Regarding the magnetoresistive sensor film having a single layer of iO50 nm, ±
It is a magnetoresistance change curve measured by applying a magnetic field of 1.5 kOe.
【００２８】固定層が第２の強磁性層１４のみである場
合には、図５および図６より、それぞれ１３００Ｏｅ、
１１００Ｏｅの磁界を印加すると、ゼロ磁界近傍におけ
る磁化状態が変わり、ΔＲが低下することが分かる。When the fixed layer is the second ferromagnetic layer 14 only, as shown in FIGS. 5 and 6, 1300 Oe,
It can be seen that when a magnetic field of 1100 Oe is applied, the magnetization state near the zero magnetic field changes, and ΔR decreases.
【００２９】一方、固定層として第３の強磁性層１２／
非磁性スペーサ層１３／第２の強磁性層１４の積層構造
を用いると、図４に示すようにＮｉＯ反強磁性層単層で
ある場合にもゼロ磁界近傍における磁化状態の変化は小
さくなるが、完全にはなくすことはできない。On the other hand, the third ferromagnetic layer 12 /
When the laminated structure of the nonmagnetic spacer layer 13 / the second ferromagnetic layer 14 is used, the change in the magnetization state near zero magnetic field is small even in the case of a single NiO antiferromagnetic layer as shown in FIG. Cannot be completely eliminated.
【００３０】ここで、反強磁性層としてＮｉＯとα−Ｆ
ｅ2Ｏ3の積層膜を用いると、図３のようにゼロ磁界近傍
での磁化状態の変化は観測されず、外部磁界に対して安
定であることが分かる。Here, NiO and α-F are used as the antiferromagnetic layer.
If a laminated film of e 2 O 3, a change in magnetization state of zero magnetic field near as in Figure 3 is not observed, it can be seen that is stable to the external magnetic field.
【００３１】図３のような外部磁界に対して安定な応答
は、第２の反強磁性層であるＮｉＯ反強磁性層の膜厚が
３０ｎｍ以上、第１の反強磁性層であるα−Ｆｅ2Ｏ3の
膜厚が０.５〜１０ｎｍの範囲で得られた。また、α−
Ｆｅ2Ｏ3の組成は必ずしも化学量論組成である必要はな
く、ＦｅxＯと表したときに０.５７≦ｘ≦０.７０の範
囲にあればよい。A stable response to an external magnetic field as shown in FIG. 3 is obtained when the thickness of the NiO antiferromagnetic layer as the second antiferromagnetic layer is 30 nm or more and the α- The thickness of Fe 2 O 3 was obtained in the range of 0.5 to 10 nm. Also, α-
The composition of Fe 2 O 3 is not necessarily a stoichiometric composition, it may be in the range of 0.57 ≦ x ≦ 0.70 when expressed as Fe x O.
【００３２】次に、上記のような特性を有する磁気抵抗
センサ膜を、磁気抵抗効果型ヘッドに適用した実施の形
態について説明する。Next, an embodiment in which the magnetoresistive sensor film having the above characteristics is applied to a magnetoresistive head will be described.
【００３３】図７は、本発明の第１の実施形態の磁気抵
抗効果型ヘッドの浮上面における構造を示す模式断面図
である。FIG. 7 is a schematic sectional view showing the structure of the air bearing surface of the magnetoresistive head according to the first embodiment of the present invention.
【００３４】セラミクスからなる非磁性基板（図示省
略）の上に、アルミナ絶縁膜（図示省略）を約１０μｍ
形成し、表面に精密研磨を施す。An alumina insulating film (not shown) is about 10 μm thick on a non-magnetic substrate (not shown) made of ceramics.
Formed and precision polished on the surface.
【００３５】下部シールド層３２として、めっき法によ
りＮｉ−Ｆｅ系合金を約２μｍ形成し、イオンミリング
により所定の形状に加工する。下部ギャップ層３３とし
てアルミナ膜を０.１μｍ成膜した後、磁気抵抗センサ
膜を形成する。反強磁性層４１として第２の反強磁性層
４１１（ＮｉＯ５０ｎｍ）と、第１の反強磁性層４１２
（α−Ｆｅ2Ｏ3２ｎｍ）とを積層した後、第３の強磁性
層４２としてＣｏ90Ｆｅ10を２.５ｎｍ、非磁性スペー
サ層４３としてＲｕを０.８ｎｍ、第２の強磁性層４４
としてＣｏ90Ｆｅ10を３.０ｎｍ成膜した。これらの３
層が固定層である。As the lower shield layer 32, a Ni—Fe alloy is formed to a thickness of about 2 μm by a plating method, and is processed into a predetermined shape by ion milling. After forming an alumina film of 0.1 μm as the lower gap layer 33, a magnetoresistive sensor film is formed. A second antiferromagnetic layer 411 (NiO 50 nm) as the antiferromagnetic layer 41 and a first antiferromagnetic layer 412
(Α-Fe 2 O 3 2 nm), 2.5 nm of Co 90 Fe 10 as the third ferromagnetic layer 42, 0.8 nm of Ru as the nonmagnetic spacer layer 43, and the second ferromagnetic layer 44
Was formed as a film of Co 90 Fe 10 having a thickness of 3.0 nm. These three
The layer is a fixed layer.
【００３６】その上に、非磁性導電層４５であるＣｕを
２.５ｎｍ、第１の強磁性層（自由層）４６であるＣｏ
１ｎｍとＮｉＦｅ５ｎｍの２層膜、保護層４７であるＴ
ａ５ｎｍを積層した。その後、磁気抵抗センサの素子高
さ方向に１５ｋＯｅの磁界を印加しながら、２５０℃、
３時間熱処理を施した。On top of this, 2.5 nm of Cu as the nonmagnetic conductive layer 45 and Co as the first ferromagnetic layer (free layer) 46 are formed.
T layer which is a two-layer film of 1 nm and NiFe
a5 nm was laminated. Then, while applying a magnetic field of 15 kOe in the element height direction of the magnetoresistive sensor,
Heat treatment was performed for 3 hours.
【００３７】この磁気抵抗センサ膜上にリフトオフマス
ク材を形成し、所定の形状に加工した後、その両端に、
硬磁性層３４としてＣｏ−Ｐｔ系合金膜、電極膜３５と
してＴａＷとＴａの積層膜を成膜した。A lift-off mask material is formed on the magnetoresistive sensor film and processed into a predetermined shape.
A Co—Pt alloy film was formed as the hard magnetic layer 34, and a laminated film of TaW and Ta was formed as the electrode film 35.
【００３８】次いで、リフトオフマスク材を除去し、上
部ギャップ層（図示省略）、上部シールド層（図示省
略）を順次形成し、その上に記録用の誘導型磁気ヘッド
を形成するが、その詳細は省略する。Next, the lift-off mask material is removed, an upper gap layer (not shown) and an upper shield layer (not shown) are sequentially formed, and an inductive magnetic head for recording is formed thereon. Omitted.
【００３９】誘導型磁気ヘッドの形成後、磁気抵抗セン
サの素子幅方向に３００Ｏｅの磁界を印加しながら、２
５０℃、３時間熱処理を行い、第２および第３の強磁性
層の磁化の方向を概ね素子高さ方向に保ったまま、第１
の強磁性層（自由層）の磁化の方向を素子幅方向に向け
た。After forming the inductive magnetic head, while applying a magnetic field of 300 Oe in the element width direction of the magnetoresistive sensor,
A heat treatment is performed at 50 ° C. for 3 hours, and the first and the second ferromagnetic layers are kept in the direction of the element height while maintaining the magnetization directions in the first ferromagnetic layer.
The direction of magnetization of the ferromagnetic layer (free layer) was oriented in the element width direction.
【００４０】上記のようにして作製した磁気抵抗効果型
ヘッドの再生出力、および、非対称性の変動率を書き込
み動作を行いながら評価した。ここで変動率は、書き込
み動作を行っていない状態での初期の出力および非対称
性の値に対する、それぞれの最大の変動分の割合と定め
た。The reproduction output and the asymmetry fluctuation rate of the magnetoresistive head manufactured as described above were evaluated while performing the writing operation. Here, the fluctuation rate is defined as the ratio of the maximum fluctuation to the initial output and the value of the asymmetry in a state where the writing operation is not performed.
【００４１】固定層が第２の強磁性層１４のみである磁
気抵抗効果型ヘッドや、固定層が第３の強磁性層１２／
非磁性スペーサ層１３／第２の強磁性層１４の積層構造
であっても、反強磁性層がＮｉＯ単層である磁気抵抗効
果型ヘッドの再生出力および非対称性の変動率が１０％
以上であるのに対し、本発明の磁気抵抗効果型ヘッドで
はいずれも２％以下と良好な結果が得られた。A magnetoresistive head in which the fixed layer is only the second ferromagnetic layer 14, or the fixed layer is the third ferromagnetic layer 12 /
Even in the laminated structure of the nonmagnetic spacer layer 13 / the second ferromagnetic layer 14, the variation in reproduction output and asymmetry of the magnetoresistive head in which the antiferromagnetic layer is a single NiO layer is 10%.
On the contrary, in the magnetoresistive head of the present invention, good results were obtained with 2% or less.
【００４２】図８は、本発明の第２の実施形態の磁気抵
抗効果型ヘッドの浮上面における構造を示す模式断面図
である。FIG. 8 is a schematic cross-sectional view showing the structure of the air bearing surface of the magnetoresistive head according to the second embodiment of the present invention.
【００４３】図８の構造は、図７の構造とほぼ同様であ
るが、電極膜３５が硬磁性層３４に対して、相対的に磁
気抵抗センサ膜のより内側まで入り込んだ構造となって
いる。この構造では、硬磁性層３４からの磁界により、
実効的に感度が悪くなっている部分の影響を除くことが
できるので、電極膜３５の間隔が狭いときに感度を向上
させることができる。The structure shown in FIG. 8 is substantially the same as the structure shown in FIG. 7, except that the electrode film 35 penetrates deeper into the magnetoresistive sensor film than the hard magnetic layer 34. . In this structure, the magnetic field from the hard magnetic layer 34 causes
Since the effect of the portion where the sensitivity is effectively deteriorated can be eliminated, the sensitivity can be improved when the interval between the electrode films 35 is narrow.
【００４４】[0044]
【発明の効果】本発明によれば、外部磁界に対して安定
で、高感度、高出力を有する磁気抵抗センサを得ること
ができる。According to the present invention, it is possible to obtain a magnetoresistive sensor which is stable against an external magnetic field, has high sensitivity and high output.
【図１】本発明の磁気抵抗センサ膜の構成を示す模式断
面図である。FIG. 1 is a schematic sectional view showing a configuration of a magnetoresistive sensor film of the present invention.
【図２】固定層が一層の強磁性層からなる従来の磁気抵
抗センサ膜の構成を示す模式断面図である。FIG. 2 is a schematic cross-sectional view illustrating a configuration of a conventional magnetoresistive sensor film in which a fixed layer includes a single ferromagnetic layer.
【図３】本発明の磁気抵抗センサ膜の磁気抵抗変化曲線
を示すグラフである。FIG. 3 is a graph showing a magnetoresistance change curve of the magnetoresistance sensor film of the present invention.
【図４】固定層が強磁性層／非磁性スペーサ層／強磁性
層からなる従来の磁気抵抗センサ膜の磁気抵抗変化曲線
を示すグラフである。FIG. 4 is a graph showing a magnetoresistive change curve of a conventional magnetoresistive sensor film in which a fixed layer includes a ferromagnetic layer / a nonmagnetic spacer layer / a ferromagnetic layer.
【図５】固定層が一層の強磁性層からなり、反強磁性層
が積層構造である従来の磁気抵抗センサ膜の磁気抵抗変
化曲線を示すグラフである。FIG. 5 is a graph showing a magnetoresistive change curve of a conventional magnetoresistive sensor film in which a fixed layer includes one ferromagnetic layer and an antiferromagnetic layer has a laminated structure.
【図６】固定層が一層の強磁性層からなり、反強磁性層
が単層構造である従来の磁気抵抗センサ膜の磁気抵抗変
化曲線を示すグラフである。FIG. 6 is a graph showing a magnetoresistive change curve of a conventional magnetoresistive sensor film in which a fixed layer includes one ferromagnetic layer and an antiferromagnetic layer has a single-layer structure.
【図７】本発明の第１の実施の形態の磁気抵抗効果型ヘ
ッドの浮上面における構造を示す模式断面図である。FIG. 7 is a schematic cross-sectional view showing a structure on the air bearing surface of the magnetoresistive head according to the first embodiment of the present invention.
【図８】本発明の第２の実施の形態の磁気抵抗効果型ヘ
ッドの浮上面における構造を示す模式断面図である。FIG. 8 is a schematic cross-sectional view showing a structure on a flying surface of a magnetoresistive head according to a second embodiment of the present invention.
１０…Ｓｉ基板、１１，４１…反強磁性層、１１１，４
１１…第２の反強磁性層、１１２，４１２…第１の反強
磁性層、１２，４２…第３の強磁性層、１３，４３…非
磁性スペーサ層、１４，４４…第２の強磁性層、１５，
４５…非磁性導電層、１６，４６…第１の強磁性層、１
７，４７…保護層、１００…第１の強磁性層の磁化の方
向、１０１…第２の強磁性層の磁化の方向、１０２…第
３の強磁性層の磁化の方向、３２…下部シールド層、３
３…下部ギャップ層、３４…硬磁性層、３５…電極膜。10: Si substrate, 11, 41: antiferromagnetic layer, 111, 4
11: second antiferromagnetic layer, 112, 412: first antiferromagnetic layer, 12, 42: third ferromagnetic layer, 13, 43: nonmagnetic spacer layer, 14, 44: second strong Magnetic layer, 15,
45: non-magnetic conductive layer, 16, 46: first ferromagnetic layer, 1
7, 47: protective layer, 100: direction of magnetization of first ferromagnetic layer, 101: direction of magnetization of second ferromagnetic layer, 102: direction of magnetization of third ferromagnetic layer, 32: lower shield Layer, 3
3: Lower gap layer, 34: Hard magnetic layer, 35: Electrode film.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平11−168250（ＪＰ，Ａ) 特開 平９−16920（ＪＰ，Ａ) ＩＥＥＥ ＴＲＡＮＳＡＣＴＩＯＮＳ ＭＡＧＮＥＴＩＣＳ，Ｖｏｌ．34，Ｎ ｏ．４，Ｊｕｌｙ 1998，ｐｐ．954− 956 (58)調査した分野(Int.Cl.7，ＤＢ名) H01L 43/00 - 43/14 H01F 10/08 G11B 5/39 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-11-168250 (JP, A) JP-A-9-16920 (JP, A) IEEE TRANSACTIONS MAGNETICS, Vol. 34, No. 4, July 1998, pp. 139-143. 954-956 (58) Fields surveyed (Int.Cl. 7 , DB name) H01L 43/00-43/14 H01F 10/08 G11B 5/39
Claims (3)
第２の強磁性層が積層され、非磁性スペーサ層を介して
前記第２の強磁性層と第３の強磁性層が積層されてお
り、前記第２の強磁性層と前記第３の強磁性層が非磁性
スペーサ層を介して反強磁性的に結合しており、前記第
１の強磁性層の磁化の方向が外部磁界ゼロのときに前記
第２の強磁性層の磁化の方向とある角度を成し、前記第
１の強磁性層の磁化の方向と前記第２の強磁性層の磁化
の方向の相対的な角度が変わることによって電気抵抗が
変化する磁気抵抗センサ膜と、前記磁気抵抗センサ膜に
信号検出電流を流すための電極と、前記磁気抵抗センサ
膜の電気抵抗変化を検知する手段を有する磁気抵抗セン
サであって、 前記第３の強磁性層が、酸化鉄ＦｅxＯ（但し、０.５７
≦ｘ≦０.７０）からなる第１の反強磁性層（膜厚：０.
５〜１０ｎｍ）の上に積層されており、 さらに、前記第１の反強磁性層が、酸化ニッケル(Ｎｉ
1-xＣｏx)Ｏ（但し、０≦ｘ≦０.５）からなる第２の反
強磁性層（膜厚：３０ｎｍ以上）の上に積層されてお
り、 前記第３の強磁性層の飽和磁束密度と膜厚の積が、前記
第２の強磁性層の飽和磁束密度と膜厚との積よりも小さ
いことを特徴とする磁気抵抗センサ。1. A first ferromagnetic layer and a second ferromagnetic layer are stacked with a nonmagnetic conductive layer interposed therebetween, and the second and third ferromagnetic layers are stacked with a nonmagnetic spacer layer interposed therebetween. Are stacked, the second ferromagnetic layer and the third ferromagnetic layer are antiferromagnetically coupled via a nonmagnetic spacer layer, and the direction of magnetization of the first ferromagnetic layer is Makes an angle with the direction of magnetization of the second ferromagnetic layer when the external magnetic field is zero, and the relative angle between the direction of magnetization of the first ferromagnetic layer and the direction of magnetization of the second ferromagnetic layer. Magnetic film having a magnetoresistive sensor film whose electric resistance changes due to a change in the electrical angle, an electrode for flowing a signal detection current through the magnetoresistive sensor film, and means for detecting a change in electric resistance of the magnetoresistive sensor film met resistance sensor, the third ferromagnetic layer, iron oxide Fe x O (where, 0.57
≦ x ≦ 0.70) of the first antiferromagnetic layer (film thickness: 0.7) .
5-10 nm) , and the first antiferromagnetic layer is made of nickel oxide (Ni
1-x Co x ) O (where 0 ≦ x ≦ 0.5), which is laminated on a second antiferromagnetic layer (thickness: 30 nm or more) . magnetoresistive sensor product of saturation magnetic flux density and the film thickness may be smaller than the product of the saturation magnetic flux density and the film thickness Metropolitan of the second ferromagnetic layer.
およびそれらの合金である請求項１に記載の磁気抵抗セ
ンサ。2. The method according to claim 1, wherein the third ferromagnetic layer is made of Fe, Co, Ni.
2. The magnetoresistive sensor according to claim 1, wherein the magnetoresistive sensor is an alloy thereof.
し、０＜ｘ≦０.２）である請求項１に記載の磁気抵抗
センサ。3. The magnetoresistive sensor according to claim 1, wherein the third ferromagnetic layer is Co 1-x Fe x (where 0 <x ≦ 0.2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10302263A JP3083090B2 (en) | 1998-10-23 | 1998-10-23 | Magnetoresistive sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10302263A JP3083090B2 (en) | 1998-10-23 | 1998-10-23 | Magnetoresistive sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000133858A JP2000133858A (en) | 2000-05-12 |
| JP3083090B2 true JP3083090B2 (en) | 2000-09-04 |
Family
ID=17906917
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10302263A Expired - Fee Related JP3083090B2 (en) | 1998-10-23 | 1998-10-23 | Magnetoresistive sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3083090B2 (en) |
-
1998
- 1998-10-23 JP JP10302263A patent/JP3083090B2/en not_active Expired - Fee Related
Non-Patent Citations (1)
| Title |
|---|
| ＩＥＥＥ ＴＲＡＮＳＡＣＴＩＯＮＳ ＭＡＧＮＥＴＩＣＳ，Ｖｏｌ．３４，Ｎｏ．４，Ｊｕｌｙ １９９８，ｐｐ．９５４−９５６ |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2000133858A (en) | 2000-05-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3291208B2 (en) | Magnetoresistive sensor, method of manufacturing the same, and magnetic head equipped with the sensor | |
| US6724585B2 (en) | Magnetoresistive element and device utilizing magnetoresistance effect | |
| JP3462832B2 (en) | Magnetic resistance sensor, magnetic head and magnetic recording / reproducing apparatus using the same | |
| JP3657916B2 (en) | Magnetoresistive head and perpendicular magnetic recording / reproducing apparatus | |
| JP2002124721A (en) | Spin valve structure and its formation method as well as reproducing head and its manufacturing method | |
| JP3269999B2 (en) | Method for manufacturing thin-film magnetic head | |
| US6545848B1 (en) | Magnetic transducer, thin film magnetic head and method of manufacturing the same | |
| JP3706793B2 (en) | Spin valve thin film magnetic element, method of manufacturing the same, and thin film magnetic head including the spin valve thin film magnetic element | |
| JP2856165B2 (en) | Magnetoresistive element and method of manufacturing the same | |
| US6765769B2 (en) | Magnetoresistive-effect thin film, magnetoresistive-effect element, and magnetoresistive-effect magnetic head | |
| JP3734716B2 (en) | Method for manufacturing magnetic sensing element | |
| US20070223147A1 (en) | Method of manufacturing thin-film magnetic head | |
| JP2006179145A (en) | Magneto-resistance effect head and manufacturing method therefor, and recording-reproduction separation type magnetic head | |
| JP2000315305A (en) | Magnetic reproducing head, magnetic head assembly, magnetic disk driving device and manufacture of magnetic head assembly | |
| JP2000113421A (en) | Magnetic tunnel junction magneto-resistive head | |
| JP3859959B2 (en) | Spin valve thin film magnetic element and thin film magnetic head provided with the spin valve thin film magnetic element | |
| JP3190193B2 (en) | How to use thin film magnetic head | |
| JP3261698B2 (en) | Magnetic head and magnetoresistive element | |
| JP3083090B2 (en) | Magnetoresistive sensor | |
| JP2000348307A (en) | Magneto-resistive element, thin-film magnetic head and their production | |
| JP3243092B2 (en) | Thin film magnetic head | |
| JPH10269532A (en) | Spin valve type magneto-resistive effect head | |
| JP3260735B2 (en) | Magnetoresistance effect element, magnetoresistance effect head, magnetic recording reproducing device and production of magnetoresistance effect head | |
| JP3764361B2 (en) | Method for manufacturing magnetoresistive element | |
| JP3840826B2 (en) | Magnetoresistive sensor and method for manufacturing magnetic head provided with the sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313115 |
|
| R360 | Written notification for declining of transfer of rights |
Free format text: JAPANESE INTERMEDIATE CODE: R360 |
|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313115 |
|
| R370 | Written measure of declining of transfer procedure |
Free format text: JAPANESE INTERMEDIATE CODE: R370 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313115 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080630 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090630 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100630 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100630 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110630 Year of fee payment: 11 |
|
| LAPS | Cancellation because of no payment of annual fees |