JPS58100215A - Magnetoresistance effect head - Google Patents

Magnetoresistance effect head

Info

Publication number
JPS58100215A
JPS58100215A JP19850581A JP19850581A JPS58100215A JP S58100215 A JPS58100215 A JP S58100215A JP 19850581 A JP19850581 A JP 19850581A JP 19850581 A JP19850581 A JP 19850581A JP S58100215 A JPS58100215 A JP S58100215A
Authority
JP
Japan
Prior art keywords
track
tracks
head
signal reproduction
magnetic permeability
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.)
Pending
Application number
JP19850581A
Other languages
Japanese (ja)
Inventor
Nobuhiro Tokujiyuku
徳宿　伸弘
Takao Arai
孝雄 荒井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP19850581A priority Critical patent/JPS58100215A/en
Publication of JPS58100215A publication Critical patent/JPS58100215A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127—Structure or manufacture of heads, e.g. inductive
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure 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
    • G11B5/3903—Structure 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
    • G11B5/3906—Details related to the use of magnetic thin film layers or to their effects
    • G11B5/3945—Heads comprising more than one sensitive element
    • G11B5/3948—Heads comprising more than one sensitive element the sensitive elements being active read-out elements
    • G11B5/3958—Heads comprising more than one sensitive element the sensitive elements being active read-out elements the active elements being arranged in a single plane, e.g. "matrix" disposition
    • G11B5/3961—Heads comprising more than one sensitive element the sensitive elements being active read-out elements the active elements being arranged in a single plane, e.g. "matrix" disposition disposed at an angle to the direction of the track or relative movement
    • G11B5/3964—Heads comprising more than one sensitive element the sensitive elements being active read-out elements the active elements being arranged in a single plane, e.g. "matrix" disposition disposed at an angle to the direction of the track or relative movement for transducing on a single track
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127—Structure or manufacture of heads, e.g. inductive
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure 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
    • G11B5/3903—Structure 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
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/127—Structure or manufacture of heads, e.g. inductive
    • G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
    • G11B5/39—Structure 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
    • G11B5/3903—Structure 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
    • G11B5/3967—Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read
    • G11B5/397—Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read with a plurality of independent magnetoresistive active read-out elements for respectively transducing from selected components
    • G11B5/3977—Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read with a plurality of independent magnetoresistive active read-out elements for respectively transducing from selected components from different information tracks
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48—Disposition 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
    • G11B5/488—Disposition of heads

Abstract

PURPOSE:To improve the S/N ratio of a track for reference audio signal reproduction, by providing a track where a magnetic material with high magnetic permeability is arranged with a nonmagnetic layer between and a track where no magnetic material with high magnetic permeability is provided on both sides of a magnetoresistance effect element in the running direction of a recording medium. CONSTITUTION:A multitrack magnetoresistance effect (MR) head consists of a substrate 1, magnetic layers 3 and 11 with high magnetic permeability, track 8 for PCM signal reproduction, and reference tracks 12 and 13. The track 8 is formed of magnetic materials 3 and 11 with high magnetic permeability, MR element 4, and barber pole electrode 5 of Al, but the tracks 12 and 13 have no magnetic layer with high magnetic permeability. Consequently, the S/N ratios of low frequency areas of the tracks 12 and 13 are improved.

Description

【発明の詳細な説明】 本発明は磁気抵抗効果ヘッド（以下へ４Ｒヘツドと略す
。）に係り、特にリファレンス音声信号再生用トラック
のＳ／Ｎ　を向上し、信頼性を向上するのに好適な複数
個の磁気抵抗効果素子を用いてなるマルチトラックＭＲ
ヘッドに関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetoresistive head (hereinafter abbreviated as 4R head), and is particularly suitable for improving the S/N of a reference audio signal reproduction track and improving reliability. Multi-track MR using multiple magnetoresistive elements
It is related to the head.

ＰＣＭ用のマルチトラックヘッドの再生ヘッドとしてＭ
Ｒヘッドが用いられている。第１図は従来のマルチトラ
ックＭＲヘッドの構造図で（ａ）は正面図、（ｂ）は平
面図である。このマルチトラックＭＲヘッドは１６トラ
ツクを有し、このうち１４トラツクをＰＣＭ信号再生用
とし、残りの２トラツクをリファレンス用のアナログ音
声信号再生用トラックとして用いている７、第１図にお
いて、１は基板、２，３はパーマロイ等の高透磁率磁性
層、４はパーマロイよりなる磁気抵抗効果を有する薄膜
の磁気抵抗効果素子、５はＡｌ　（アルミニウム）より
なるバーバーポール電極、６はＡＡよりなる引出し電極
（第１図（ｂ）では図示省略）である。バーバーポール
電極５は、ＭＲヘッドの線形性を改善する目的で設けで
ある。８はＰＣＭ信号再生用トラック、９はリファレン
ス音声信号再生用トラックを示している。なお、リファ
レンス音声信号再生用トラツク９よりもＰＣＭ信号再生
用トラック８の方が重要であるため、図に示すように、
比較的テープのいたみの少ない中央部にＰＣＭ信号再生
用トラック８を設け、その両側に音声信号再生用トラッ
ク９を設けている。M as a playback head of a multi-track head for PCM
R head is used. FIG. 1 is a structural diagram of a conventional multi-track MR head, in which (a) is a front view and (b) is a plan view. This multi-track MR head has 16 tracks, of which 14 tracks are used for reproducing PCM signals, and the remaining two tracks are used as reference tracks for reproducing analog audio signals. A substrate, 2 and 3 are high permeability magnetic layers such as permalloy, 4 is a thin film magnetoresistive element having a magnetoresistive effect made of permalloy, 5 is a barber pole electrode made of Al (aluminum), and 6 is a drawer made of AA. This is an electrode (not shown in FIG. 1(b)). The barber pole electrode 5 is provided for the purpose of improving the linearity of the MR head. Reference numeral 8 indicates a track for reproducing a PCM signal, and reference numeral 9 indicates a track for reproducing a reference audio signal. Note that since the PCM signal reproduction track 8 is more important than the reference audio signal reproduction track 9, as shown in the figure,
A PCM signal reproducing track 8 is provided in the center where the tape is relatively less damaged, and audio signal reproducing tracks 9 are provided on both sides thereof.

第２図は第１図のＭＲヘッドの再生出力の周波数特性と
ヘッドインピーダンスノイズスペクトルを示した線図で
、ａは再生出力、ｂはヘッドインピーダンスノイズを示
している。ＰＣＭ信号の１トラツクあたりの主な使用周
波数帯域は、１０〜５０山であり、この周波数範囲では
、再生出力がヘッドインピータンスよりも十分大きく、
Ｓ／Ｎが十分とられているので、ＰＣＭ信号再生用トラ
ック８については問題ないが、音声信号再生用トラック
９については、音声信号は数Ｈｚから２０山までの周波
数帯域であるため、特に低周波数領域でＳ／Ｎが十分で
なくなるという問題を生ずる。FIG. 2 is a diagram showing the frequency characteristics of the reproduced output and the head impedance noise spectrum of the MR head shown in FIG. 1, where a indicates the reproduced output and b indicates the head impedance noise. The main frequency band used per PCM signal track is 10 to 50 peaks, and in this frequency range, the reproduction output is sufficiently larger than the head impedance.
Since the S/N is sufficient, there is no problem with the PCM signal reproduction track 8, but the audio signal reproduction track 9 has a frequency range from several Hz to 20 peaks, so there is no problem with the PCM signal reproduction track 8. This causes a problem that the S/N ratio is not sufficient in the frequency domain.

本発明は上記に鑑みてなされたもので、その目的とする
ところは、リファレンス音声信号再生用トラックのＳ／
Ｎを向上できるマルチトラックの磁気抵抗効果ヘッドを
提供することにある。The present invention has been made in view of the above, and its purpose is to
An object of the present invention is to provide a multi-track magnetoresistive head that can improve N.

本発明の特徴は、トラックを磁気抵抗効果菓子の磁気記
録媒体走行方向側の両側に非磁性層を介して高透磁率磁
性体を配置した第１トラツクと上記高透磁率磁性体のう
ち少なくとも片側のない第２トラツクとに分けた構成と
した点にある。The present invention is characterized in that the track includes a first track in which a high magnetic permeability magnetic material is arranged on both sides of the magnetoresistive confectionery in the running direction of the magnetic recording medium via a nonmagnetic layer, and at least one side of the high magnetic permeability magnetic material. The main point is that the track is divided into a second track and a second track.

以下本発明を第６図、第５図、第６図に示した実施例お
よび第４図を用いて詳細に説明する。The present invention will be explained in detail below using the embodiments shown in FIGS. 6, 5, and 6 and FIG. 4.

第３図は本発明のマルチトラックＭ　Ｒヘッドの一実施
例を示す構造図で、（ａ）は正面図、（ｂ）は平面図で
ある。第３図において、１は基板、３゜１１は高透磁率
磁性層、８はＰＣＭ信号再生用トラック、　１２．１３
はリファレンス音声信号再生用トラックで図示したよう
に、ＰＣＭ信号再生用トラック８は、第１図と同一構成
としであるが音声信号再生用トラック１２．１３は、高
透磁率磁性層がない構成としである。FIG. 3 is a structural diagram showing an embodiment of the multi-track MR head of the present invention, in which (a) is a front view and (b) is a plan view. In FIG. 3, 1 is a substrate, 3° 11 is a high permeability magnetic layer, 8 is a PCM signal reproduction track, 12.13
As shown in the reference audio signal reproduction track 8, the PCM signal reproduction track 8 has the same configuration as in FIG. 1, but the audio signal reproduction tracks 12 and 13 have a configuration without a high permeability magnetic layer. It is.

第４図は第３図のマルチトラックＭＲヘッドの再生出力
の周波数特性とへラドインピーダンスノイズスペクトル
を示しだ線図で、ｃはＰｃＭ信号再生用トラック８の再
生出力の周波数特性を示す曲線、ｄは音声信号再生用ト
ラック１２゜１６の再生出力の周波数特性を示す曲線、
ｅはトラック８　、１２．１３のへラドインピーダンス
ノイズスペクトルを示す曲線で、いずれも実験結果を示
しである。このように、トラック１２．１３の再生出力
は、低周波領域でトラック８のものにくらべて約２０６
ｉ３改善されており、１０　ＫＨｚ以上の領域ではほぼ
同一レベルとなっている。また、ヘッドインピーダンス
ノイズは、トラック８　、１２゜１６とも同一であるた
め、音声信号再生用トラック１２’、１３の低周波数領
域でのＳ／Ｎは大幅に改善されることになる。こればと
もない信頼性を改善できる。FIG. 4 is a diagram showing the frequency characteristics of the reproduction output of the multi-track MR head in FIG. is a curve showing the frequency characteristics of the playback output of the audio signal playback track 12°16,
e is a curve showing the helad impedance noise spectrum of tracks 8 and 12.13, both of which are experimental results. In this way, the playback output of tracks 12 and 13 is approximately 206 times higher than that of track 8 in the low frequency range.
i3 has been improved, and the level is almost the same in the region of 10 KHz and above. Furthermore, since the head impedance noise is the same for tracks 8 and 12.degree. 16, the S/N ratio in the low frequency region of the audio signal reproduction tracks 12' and 13 is significantly improved. This can improve reliability tremendously.

第５図は本発明の他の実施例を示す構造図で（ａ）は正
面図、（ｂ）は平面図で、第６図と同一部分は同じ符号
で示しである。第５図においては、音声信号再生用トラ
ックは、磁気抵抗効果を有する薄膜４の下部に非磁性層
２１を設けた構成の音声信号再生用トラック２２．２３
としである。その他は第６図と同様である。第４図に示
した実施例では、音声信号再生用トラック１２．１３は
磁性層１１の厚さ分だけＰＣＭ信号再生用トラック８よ
りずれ、磁性層１１の厚さが２μｍ　１テ一プ速度が４
．８　’″／、！とすると、４０μｓｅｃの時間ずれが
生ずるが、第５図においては、それを非磁性層２１の厚
さを磁性層１１と同じ厚さにすることによりカバーする
ことができる。その他の効果については第３図と同じで
ある。FIG. 5 is a structural view showing another embodiment of the present invention, in which (a) is a front view and (b) is a plan view, in which the same parts as in FIG. 6 are designated by the same reference numerals. In FIG. 5, the audio signal reproducing tracks 22 and 23 have a structure in which a nonmagnetic layer 21 is provided under a thin film 4 having a magnetoresistive effect.
It's Toshide. Other details are the same as in FIG. 6. In the embodiment shown in FIG. 4, the audio signal reproduction tracks 12 and 13 are shifted from the PCM signal reproduction track 8 by the thickness of the magnetic layer 11, and the thickness of the magnetic layer 11 is 2 μm. 4
．． 8'''/,!, a time lag of 40 μsec occurs, but in FIG. 5, this can be covered by making the nonmagnetic layer 21 the same thickness as the magnetic layer 11. Other effects are the same as in FIG. 3.

第６図は本発明のさらに他の実施例を示す構造図で、（
ａ）は正面図、（ｂ）は平面図で、第３図と同一部分は
同じ符号で示しである。第６図においては、音声信号再
生用トラックは、高透磁率磁性層２のみがあり、第１図
の高透磁率磁性層３を取り去った構成の音声信号再生用
トラック３１．３２としである。第６図に示した実施例
によれば、作製法が簡単となり、また、低周波数領域で
の音声トラック３１．３２の再生出力を向上することか
できる。FIG. 6 is a structural diagram showing still another embodiment of the present invention.
(a) is a front view, (b) is a plan view, and the same parts as in FIG. 3 are designated by the same reference numerals. In FIG. 6, the audio signal reproducing tracks 31 and 32 have only the high permeability magnetic layer 2, and the high permeability magnetic layer 3 of FIG. 1 is removed. According to the embodiment shown in FIG. 6, the manufacturing method is simple and the reproduction output of the audio tracks 31 and 32 in the low frequency region can be improved.

なお、上記した各実施例においては、リファレンス用の
音声信号再生用トラックについて説明したが、これのみ
に限定されるものでなく、ヘッド位置のコントロール信
号用トラックにも適用することができることはいうまで
もない。In each of the above-mentioned embodiments, the reference audio signal reproduction track has been described, but the present invention is not limited to this, and it goes without saying that the present invention can also be applied to a head position control signal track. Nor.

以上説明したように、本発明によれば、リファレンス音
声信号再生用トラックのＳ／Ｎを向上することができ、
ＰＣＭ用マルチトラックの磁気抵抗効果ヘッドの信頼性
を改善できるという効果がある。As explained above, according to the present invention, it is possible to improve the S/N of the reference audio signal reproduction track,
This has the effect of improving the reliability of a multi-track magnetoresistive head for PCM.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は従来のマルチトラックＭＲヘッドの構造図、第
２図は第１図のＭ’　Ｒヘッドの再生出力の周波数特性
とへッドインビ　ダンスノイズスペクトルを示した線図
、第３図は本発明のマルチトラックＭＲヘッドの一実施
例を示す構造図、第４図は第３図のＭＲヘッドの再生出
力の周波数特性とヘッドインピーダンスノイズスペクト
ルを示した線図、第５図、第６図はそれぞれ本発明の他
の実施例を示す構造図である。 ２．３．１１・・・高透磁率磁性層 ４・・・磁気抵抗効果素子 ５・・・バーバーポール電極 ６・・・引出し電極 ８・・・Ｐ　ＣＭ信号再生用トラック １２、１３．２２．２３．３１．３２・・・リファレン
ス音声信号再生用トラック ２１・・・非磁性層 第１図 第２図 ｎ取数（Ｈ２） 第３図 （＋）） 糖４図 乱皮数（Ｈｚ） 第Ｓ図 第６図 （ＯＬ）Fig. 1 is a structural diagram of a conventional multi-track MR head, Fig. 2 is a diagram showing the frequency characteristics of the reproduction output of the M'R head shown in Fig. 1 and a head-impedance noise spectrum, and Fig. 3 is a diagram showing the head impedance noise spectrum of the M'R head of Fig. 1. Fig. 4 is a diagram showing the frequency characteristics of the reproduction output of the MR head shown in Fig. 3 and a head impedance noise spectrum, and Figs. FIG. 3 is a structural diagram showing another embodiment of the present invention. 2.3.11... High permeability magnetic layer 4... Magnetoresistive element 5... Barber pole electrode 6... Extraction electrode 8... P CM signal reproduction track 12, 13.22. 23.31.32...Reference audio signal reproduction track 21...Non-magnetic layer Fig. 1 Fig. 2 n number (H2) Fig. 3 (+)) Sugar Fig. 4 random number (Hz) S diagram Figure 6 (OL)

Claims (1)

【特許請求の範囲】 １、　複数個の磁気抵抗効果素子を備えだマルチトラッ
ク磁気抵抗効果ヘッドにおいて、トラックを前記磁気抵
抗効果素子の磁気記録媒体走行方向側の両側に非磁性層
を介して高透磁率磁性体を配置した第１トラツクと、前
記高透磁率磁性体のうち少なくとも片側のない第２トラ
ツクとに分けた構成としであることを特徴とする磁気抵
抗効果ヘッド。 ２、　前記第１トラツクをＰＣＭ信号再生用トラックと
し、前記第２トラツクをリファレンス音声信号再生用ト
ラックとしである特許請求の範囲第１項記載の磁気抵抗
効果ヘッド。[Claims] 1. In a multi-track magnetoresistive head equipped with a plurality of magnetoresistive elements, tracks are arranged on both sides of the magnetoresistive element in a magnetic recording medium traveling direction via a nonmagnetic layer. A magnetoresistive head characterized in that it is divided into a first track on which a magnetic material with magnetic permeability is arranged and a second track in which at least one side of the magnetic material with high magnetic permeability is absent. 2. The magnetoresistive head according to claim 1, wherein the first track is a PCM signal reproduction track, and the second track is a reference audio signal reproduction track.
JP19850581A 1981-12-11 1981-12-11 Magnetoresistance effect head Pending JPS58100215A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19850581A JPS58100215A (en) 1981-12-11 1981-12-11 Magnetoresistance effect head

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19850581A JPS58100215A (en) 1981-12-11 1981-12-11 Magnetoresistance effect head

Publications (1)

Publication Number Publication Date
JPS58100215A true JPS58100215A (en) 1983-06-14

Family

ID=16392246

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19850581A Pending JPS58100215A (en) 1981-12-11 1981-12-11 Magnetoresistance effect head

Country Status (1)

Country Link
JP (1) JPS58100215A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0702357A3 (en) * 1994-09-16 1996-11-27 Toshiba Kk Magneto-resistance effect head and magnetic recording/reproducing head thereof
US6256171B1 (en) 1996-09-30 2001-07-03 Kabushiki Kaisha Toshiba Thin film magnetic head having an improved heat dispersion and magnetic recording apparatus using the same

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0702357A3 (en) * 1994-09-16 1996-11-27 Toshiba Kk Magneto-resistance effect head and magnetic recording/reproducing head thereof
US6256171B1 (en) 1996-09-30 2001-07-03 Kabushiki Kaisha Toshiba Thin film magnetic head having an improved heat dispersion and magnetic recording apparatus using the same

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