JP3578471B2 - The thin-film magnetic head - Google Patents

The thin-film magnetic head Download PDF

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JP3578471B2
JP3578471B2 JP13702993A JP13702993A JP3578471B2 JP 3578471 B2 JP3578471 B2 JP 3578471B2 JP 13702993 A JP13702993 A JP 13702993A JP 13702993 A JP13702993 A JP 13702993A JP 3578471 B2 JP3578471 B2 JP 3578471B2
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head
magnetic pole
recording
track width
width
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JPH06349026A (en
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真治 古市
邦明 吉村
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アルプス電気株式会社
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    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127Structure or manufacture of heads, e.g. inductive
    • G11B5/33Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
    • G11B5/3903Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects using magnetic thin film layers or their effects, the films being part of integrated structures
    • G11B5/3967Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127Structure or manufacture of heads, e.g. inductive
    • G11B5/31Structure or manufacture of heads, e.g. inductive using thin films
    • G11B5/3109Details
    • G11B5/313Disposition of layers
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127Structure or manufacture of heads, e.g. inductive
    • G11B5/31Structure or manufacture of heads, e.g. inductive using thin films
    • G11B5/3176Structure of heads comprising at least in the transducing gap regions two magnetic thin films disposed respectively at both sides of the gaps
    • G11B5/3179Structure of heads comprising at least in the transducing gap regions two magnetic thin films disposed respectively at both sides of the gaps the films being mainly disposed in parallel planes
    • GPHYSICS
    • G11INFORMATION STORAGE
    • G11BINFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/488Disposition of heads

Description

【0001】 [0001]
【産業上の利用分野】 BACKGROUND OF THE INVENTION
本発明はハードディスク装置等に使用する薄膜磁気ヘッドに関する。 The present invention relates to a thin film magnetic head used in a hard disk device or the like. 特に記録と再生とを分離し、再生を磁気抵抗効果型ヘッドで行なう記録再生分離型ヘッドの磁気シールドを十分なものとし、かつ、オフトラックに起因する出力低下やノイズを低減したものである。 In particular recording and separates the reproduction, the magnetic shield of the reproducing separation type head reproducing magnetoresistive effect head and sufficient, and is obtained by reducing the output reduction and noise caused by the off-track.
【0002】 [0002]
【従来の技術】 BACKGROUND OF THE INVENTION
薄膜磁気ヘッドを適用した浮上型磁気ヘッドとして、図3にその断面図を示すように、基体31上に磁気抵抗効果型再生ヘッド、誘導型記録ヘッドの順に積層した記録再生分離型薄膜磁気ヘッドがある。 As floating magnetic head according to the thin-film magnetic head, as shown in the sectional view thereof in FIG. 3, the magnetoresistive read head on a substrate 31, a recording reproducing separate type thin film magnetic head is formed by laminating in this order inductive recording head is there. 図3においては記録ヘッドのパターン形成した下部磁極36は、再生ヘッドの上部シールド部材33を兼用しており、記録ヘッドの中心は、アジマス効果を出すために再生ヘッドの中心とはオフセンターfの分だけずらして構成してある。 The lower magnetic pole 36 patterned in the recording head 3 is also used as an upper shield member 33 of the reproducing head, the center of the recording head, the center of the reproducing head in order to give azimuth effect of off-center f It is constructed by shifting by the amount.
【0003】 [0003]
【発明が解決しようとする課題】 [Problems that the Invention is to Solve
しかしながら、オフセンターfの値は設計するドライブ毎に替えることが必要であり、マスクの準備等生産コストの増加と、複雑な工程管理が必要となる。 However, the value of the off-center f is required to be replaced for each drive to be designed, made and increase preparation such production cost of the mask, and requires complex process control. 又、図3の録再分離型薄膜ヘッドに見られるように、オフセンターfに対して許容性をもたすために、再生ヘッドの下部シールド部材32と記録ヘッドの下部磁極36は幅を同一にしてある。 Identical Also, as seen in the recording and reproducing separation type thin film head of FIG. 3, in order to Motas the permissive for off-center f, a lower shield member 32 of the reproducing head lower magnetic pole 36 and the width of the recording head are to. このために、記録ヘッドとして見れば、上部磁極37の幅と下部磁極36の幅とがその大きさが著しく異なる為に、記録時に記録磁界の書きにじみなどトラック幅方向磁界の乱れが大きくなりノイズ発生要因となる。 For this, when viewed as a recording head, for the width of the lower magnetic pole 36 of the upper magnetic pole 37 is different significantly in size, turbulence in the track width direction magnetic field, such as write bleeding of the recording magnetic field at the time of recording becomes large noise the generation factor.
【0004】 [0004]
【課題を解決するための手段】 In order to solve the problems]
上記課題を解決するために本発明は、記録ヘッドの下部磁極に再生ヘッドの上部シールド材を兼ねさせると共に、上部磁極のトラック幅と実質的に同一寸法に下部磁極のトラック幅を規制する切り欠け部を設けた薄膜磁気ヘッドである。 The present invention in order to solve the above problems, as well as serve also as the upper shield member of the reproducing head to the lower magnetic pole of the recording head, notch for restricting the track width of the lower magnetic pole in the track width substantially the same dimensions of the upper magnetic pole parts is a thin film magnetic head provided with a.
前記下部磁極の切り欠け部は、例えばオフセンターfを出すためにパターン形成した上部磁極をトリミングする際に、作成することができる。 Cutout of the lower magnetic pole, when trimming the upper magnetic pole that is patterned in order to give example off-center f, can be created. この場合に、上部磁極の除去する位置をトラック幅方向左右にずらすことにより、オフセンターfを調整し、除去する部分を調整することによって、トラック幅(Tw)を変えることができる。 In this case, by shifting the position of the removal of the upper magnetic pole in the lateral track width direction, by adjusting the off-center f, by adjusting a part to be removed, it is possible to change the track width (Tw). 上部磁極の除去する位置をトラック幅方向にずらす事により、上部磁極及び下部磁極は僅か左右非対象形となるが、記録特性には何等支障はないものである。 By shifting the position of the removal of the upper magnetic pole in the track width direction, but the upper pole and the lower magnetic pole becomes slightly horizontally asymmetric shape, but not any problem in recording characteristics.
【0005】 [0005]
【作用】 [Action]
下部磁極は、再生ヘッドの磁気シールド材を兼ねているが、上部磁極の幅と実質的に同一寸法のトラック幅を切り欠けによって形成することができる。 The lower magnetic pole is also serves as a magnetic shield material of the reproducing head may be formed by chipping off the track width of substantially the same dimensions of the upper magnetic pole. 切り欠き部のトラック方向幅Wは、記録時の書きにじみを少なくする為に、記録ヘッドのギャップ長さ(Gl)と同じか、それよりも長いものとすることが好ましい。 Track width W of the notch, in order to reduce the write bleeding at the time of recording, or the same as the gap length of the recording head (Gl), it is preferable that it longer than. 切り欠き部の膜厚方向深さdは磁気シールド効果を減じない程度まで深くすることは可能である。 Thickness direction depth d of the notch is possible to deeply to the extent that they do not reduce the magnetic shielding effect. この深さdは、好ましくは、下部磁極膜厚Gの1/40〜1/2程度である。 The depth d is preferably about 1 / 40-1 / 2 of the lower magnetic pole thickness G.
【0006】 [0006]
【実施例】 【Example】
図1は、第1の実施例を説明するための薄膜磁気ヘッドの斜視部分断面図である。 Figure 1 is a perspective partial cross-sectional view of a thin film magnetic head for illustrating the first embodiment. スライダーとなる基体1上に磁気抵抗効果型再生ヘッド、その上に誘導型記録ヘッドを積層してある。 Magnetoresistive read head on a substrate 1 made of a slider, it is stacked the inductive recording head thereon. 磁気抵抗効果型ヘッドは磁気シールド層2及び3(3は、記録ヘッドの下部磁極を兼ねる)の間に磁気抵抗効果膜4を積層し、両端を電極5で接続して、電極の間隔を再生ヘッドのトラック幅としている。 Magnetoresistive head is a magnetic shielding layer 2 and 3 (3, serving as a lower magnetic pole of the recording head) of the magnetoresistive film 4 is laminated between, and connected at both ends with electrodes 5, reproducing the distance between the electrodes It has a track width of the head. この上に記録ヘッドの下部磁極6、上部磁極7およびこれらの間にギャップ層8とコイル9を設ける。 Lower magnetic pole 6 of the recording head thereon, providing a gap layer 8 and the coil 9 to the upper pole 7 and between them. ここでシールド層および記録磁極はパーマロイなどの軟磁性膜であればよく、他のCo系や、Fe系の軟磁性膜であってもかまわない。 Here shielding layer and the recording magnetic pole may be a soft magnetic film such as permalloy, other Co-based or may be a soft magnetic film of Fe-based. また磁気抵抗効果膜にはパーマロイを用い、膜厚は20nmとした。 The use of a permalloy magnetoresistive effect film, the film thickness was 20 nm. また、記録トラック幅は4μmとし、再生トラック幅は2μmである。 The recording track width is set to 4 [mu] m, a reproducing track width of 2 [mu] m. 再生ヘッドのトラック幅は記録トラック幅の1/2以下であるため、高再生出力化を計る必要がある。 The track width of the reproducing head is because less than half of the recording track width, it is necessary to measure the high-quality reproduction output of. 磁気抵抗効果型ヘッドの出力はパーマロイの膜厚を薄くするほど高くできるので、薄膜化による磁気特性や電気特性の劣化が顕著になる限界まで薄くすることが好ましい。 Since the output of the magnetoresistive head can high enough to reduce the film thickness of the permalloy, it is preferable that the deterioration of the magnetic and electrical properties due to thinning is thin to the limit that becomes remarkable. さらに、浮上面から見たときの磁気抵抗効果膜の奥行きは、狭いほど高出力化を図ることができる。 Further, the depth of the magnetoresistive film when viewed from the air bearing surface, it is possible to narrow as the higher output.
【0007】 [0007]
なお上記の図中では省略して記載しなかったが、通常磁気抵抗効果型ヘッドでは出力の線形性を向上するために、バイアス磁界を印加する手段が必要である。 Note the in the figure above have not been described are omitted, but a normal magneto-resistive head in order to improve the linearity of the output, there is a need for a means for applying a bias magnetic field. この方法としてはシャントバイアス、ソトトバイアス、永久磁石バイアスなど従来から知られており、これらのバイアス手段を用いることができる。 As the method shunt bias, Sototobaiasu, have been known such as a conventional permanent magnet bias, it is possible to use these biasing means. 記録ヘッドと再生ヘッドの中心位置は一般にはずれている。 The center position of the recording head reproducing head is generally off. ヘッドがディスクの半径方向にシークすることによって媒体との相対速度が変化するので、浮上量も変化する。 Since the head relative speed between the medium changes by seeking in the radial direction of the disk, also changes the flying height. 磁気抵抗効果型ヘッドの場合、出力は媒体の速度に依存しないため、浮上量の大きい外周側の特性が内周側の特性よりも劣る。 For a magnetoresistive head, the output does not depend on the velocity of the medium, less than larger outer peripheral side of the characteristics of the inner peripheral side characteristic of the flying height. これを補うためには、特性劣化のある外周側で最もトラック幅が増大するように、媒体とヘッド間のアジマス角をゼロにすることが好ましい。 To compensate for this, as best track width on the outer peripheral side with a characteristic degradation is increased, it is preferable to set the azimuth angle between the medium and the head to zero. このため、内周側にシークしていくほど記録ヘッドと再生ヘッドのずれは単調に増加する。 Therefore, the deviation between the recording head and reproducing head as continue to seek the inner peripheral side is increased monotonically. したがって、本図に示したようにあらかじめシークによるヘッド間のずれ分だけ記録ヘッドと再生ヘッドの中心をずらしておくことによって、内周側においても常に記録トラックの内側に再生ヘッドがくるようにできるので良好なオフトラック特性を持つ磁気記録装置を提供できる。 Therefore, the deviation amount corresponding to the recording head between the head by pre-seek as indicated in the figure by leaving staggered center of the reproducing head can be always as the inside of the recording tracks come reproducing head even in the inner because it provides a magnetic recording apparatus having good off-track characteristics.
【0008】 [0008]
また外周側の浮上量を増加させない方法として、媒体との相対速度に関係なく浮上量が一定になる定浮上ヘッドが提案されている(米国特許4,673,996号 Mr.James White)ヘッドと媒体の進入角度(skew角)を付与する事により浮上量の変化を得、周速による浮上量変化量とskew角による浮上量変化量を相殺させ定浮上ヘッドを供給するものである。 As also the method does not increase the flying height of the outer peripheral side, the constant flying head has been proposed (Mr.James White U.S. Pat. No. 4,673,996) that a constant flying height, regardless of the relative velocity between the medium head and the resulting changes in the flying height by imparting entry angle of the medium (skew angle), and supplies a constant flying head to offset the flying height variation due to the flying height variation and skew angle due to the circumferential speed. しかしこの場合においても、シークによるヘッド間のずれ分だけ記録ヘッドと再生ヘッドの中心をずらしておく事によりより良好なオフトラック特性が得られる事は言うまでもない。 However, even in this case, it is needless to say better be off-track characteristics are obtained by keep shifting the shift amount corresponding centers of the recording head reproducing head between head according seek.
【0009】 [0009]
上部磁極のトリミングは、レジストマスクを利用して、IBE( Ion Beam Etching )やFIB( Focused Ion Beam )等を用いて行い、同時に上部シールドを兼ねる下部磁極に切り欠きを設けるエッチングを行う。 Trimming the upper magnetic pole, using the resist mask, using IBE (Ion Beam Etching) and FIB (Focused Ion Beam) or the like, etching is performed to provide a notch in the lower magnetic pole which also serves as an upper shield simultaneously.
図2には別の実施例の上部磁極27、下部磁極28の断面図を示して有る。 The top pole 27 of the alternative embodiment in FIG. 2, there shows a cross-sectional view of the lower magnetic pole 28. 同図は、磁気ディスク面から見たヘッドの断面図である。 The figure is a cross-sectional view of the head viewed from the magnetic disk surface. 下部磁極は、再生ヘッドの磁気シールドを兼ねているが、上部磁極の幅とほぼ同一寸法のトラック幅を一対の切り欠き部によって形成することができる。 The lower magnetic pole is also serves as a magnetic shield of the read head, it is possible to form a track width of approximately the same size as the width of the upper magnetic pole by a pair of notches. 切り欠き部のトラック方向幅wは記録時に書きにじみを少なくする為に、記録ヘッドのギャップ長さ(G1)と同じか、それよりも長いものとすることが好ましい。 The track width w of the notch in order to reduce the write bleeding during recording, or equal to the gap length of the recording head (G1), it is preferable that it be longer than. 切り欠き部の膜厚方向深さdは磁気シールド効果を減じない程度まで深くすることは可能である。 Thickness direction depth d of the notch is possible to deeply to the extent that they do not reduce the magnetic shielding effect. この深さdは、好ましくは、下部磁極膜厚Gの1/40から1/2程度である。 The depth d is preferably about 1/2 from 1/40 of the lower magnetic pole thickness G.
【0010】 [0010]
【発明の効果】 【Effect of the invention】
本発明により、工程を複雑にすることなく、上部磁極のトリミングに依って上部磁極の中心線と再生ヘッドの中心線のズレ量(オフセンターf)を上部磁極形成後に、精度良く得ることができる。 The present invention, without complicating the process, can shift amount of the center line of the reproducing head center line of the top pole (off-center f) after the upper magnetic pole formed depending on the trimming of the upper magnetic pole, accurately obtain .
また、記録用上下磁極幅がほぼ同一になる事により記録時の書きにじみによる実質的な書き込みトラック幅の増加をおさえる事ができる。 Further, it is possible to suppress the increase of the substantial write track width by write bleeding time recording by the recording vertical pole width is approximately the same. 本発明により、上部磁極を形成した後、オフセンターfと記録トラック幅を前述方法により得る為、オフセンターfと記録トラック幅の組合せ自由度が飛躍的に増大する。 The present invention, after forming the upper magnetic pole, in order to obtain the off-center f the above method the recording track width, combined flexibility of the recording track width and the off-center f increases dramatically.
【図面の簡単な説明】 BRIEF DESCRIPTION OF THE DRAWINGS
【図1】実施例の薄膜磁気ヘッドの斜視部分断面図である。 1 is a perspective partial cross-sectional view of a thin film magnetic head of the embodiment.
【図2】本発明の別の実施例の断面図である。 2 is a cross-sectional view of another embodiment of the present invention.
【図3】従来の薄膜磁気ヘッドの断面図である。 3 is a cross-sectional view of a conventional thin film magnetic head.
【符号の説明】 DESCRIPTION OF SYMBOLS
1 基板2 下部磁気シールド層3 上部磁気シールド層4 磁気抵抗効果膜5 電極6 下部磁極7 上部磁極 1 substrate 2 lower magnetic shield layer 3 upper magnetic shield layer 4 magnetoresistive film 5 electrode 6 lower magnetic pole 7 top pole

Claims (2)

  1. 基体上に磁気抵抗効果型再生ヘッド、誘導型記録ヘッドの順に積層した分離型ヘッドにおいて、上記磁気抵抗効果型再生ヘッドの上部シールド部材を誘導型記録ヘッドの下部磁極として、下部磁極にはそのトラック幅を、上部磁極のトラック幅と同一寸法に規制する切り欠き部を設け、前記切り欠き部は上部シールドを幅Wで切り欠いた凹みであり、 幅Wは記録ヘッドのギャップ長さGl以上の大きさであることを特徴とする薄膜磁気ヘッド。 Magnetoresistive read head on a substrate, the separation type head formed by laminating in this order inductive recording head, an upper shield member of the magnetoresistive read head as the bottom pole of the induction type recording head, the lower magnetic pole that track width, the provided notch portion for restricting the same size as the track width of the upper magnetic pole, the cutout portion is a recess cut away the upper shield in the width W, the width W is in the recording head gap length Gl more thin-film magnetic head, characterized in that a size.
  2. 請求項1において、 記切り欠き部の深さd は、下部磁極膜厚Gの1/40〜1/2の範囲内であることを特徴とする薄膜磁気ヘッド。 In claim 1, the depth d of the front Symbol notch a thin film magnetic head, characterized in that it is in the range of 1 / 40-1 / 2 of the lower magnetic pole thickness G.
JP13702993A 1993-06-08 1993-06-08 The thin-film magnetic head Expired - Fee Related JP3578471B2 (en)

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JP3578471B2 true JP3578471B2 (en) 2004-10-20

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AU6675298A (en) * 1997-03-04 1998-09-22 Micrion Corporation Thin-film magnetic recording head manufacture
US5916424A (en) 1996-04-19 1999-06-29 Micrion Corporation Thin film magnetic recording heads and systems and methods for manufacturing the same
JPH10228607A (en) * 1997-02-14 1998-08-25 Fujitsu Ltd Magnetic head and production therefor and magnetic storage
JPH117608A (en) 1997-04-25 1999-01-12 Fujitsu Ltd Magnetic head and its manufacture
US6332962B1 (en) 1997-06-13 2001-12-25 Micrion Corporation Thin-film magnetic recording head manufacture using selective imaging
JPWO2003083837A1 (en) 2002-04-01 2005-08-04 富士通株式会社 Thin-film magnetic head and manufacturing method thereof

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