JPH0671101B2 - Superconductor Magnetoresistive element - Google Patents

Superconductor Magnetoresistive element

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Publication number
JPH0671101B2
JPH0671101B2 JP62331008A JP33100887A JPH0671101B2 JP H0671101 B2 JPH0671101 B2 JP H0671101B2 JP 62331008 A JP62331008 A JP 62331008A JP 33100887 A JP33100887 A JP 33100887A JP H0671101 B2 JPH0671101 B2 JP H0671101B2
Authority
JP
Japan
Prior art keywords
superconductor
magnetoresistive element
magnetic field
ceramic
resistance
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
Application number
JP62331008A
Other languages
Japanese (ja)
Other versions
JPH01173507A (en
Inventor
照栄 片岡
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.)
Sharp Corp
Original Assignee
Sharp Corp
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 Sharp Corp filed Critical Sharp Corp
Priority to JP62331008A priority Critical patent/JPH0671101B2/en
Priority to DE3888659T priority patent/DE3888659T2/en
Priority to EP88312296A priority patent/EP0323187B1/en
Priority to US07/289,312 priority patent/US5126667A/en
Priority to CN 88109265 priority patent/CN1022348C/en
Publication of JPH01173507A publication Critical patent/JPH01173507A/en
Priority to US07/593,898 priority patent/US5227721A/en
Publication of JPH0671101B2 publication Critical patent/JPH0671101B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/60—Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment

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  • Measuring Magnetic Variables (AREA)
  • Superconductor Devices And Manufacturing Methods Thereof (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)

Description

【発明の詳細な説明】 ＜産業上の利用分野＞ 本発明は、結晶粒界を有するセラミック超電導体からな
り、その素子自体は磁場を作らない、線状にした磁気抵
抗素子に関するものである。Description: TECHNICAL FIELD The present invention relates to a linear magnetoresistive element which is composed of a ceramic superconductor having crystal grain boundaries and whose element itself does not generate a magnetic field.

＜従来の技術＞ 従来の磁気抵抗素子は、半導体又は磁性体を用いてい
た。しかしその感度を示す磁界密度と抵抗変化率は第２
図に示すように磁場の強さの増加に対する、磁気抵抗素
子の抵抗の増加は２次曲線になり、測定する磁場の強さ
が弱いときは、磁場の大きさＢに対する抵抗の変化であ
るΔＲが小さく、数＋ガウスの磁場の変化に対し、ΔR/
R0は１％以下であった。（R0は、磁場が０のときの磁気
抵抗素子の抵抗値）従来の磁気抵抗素子のを改良し、磁
場に対する感度を向上させ、微弱な磁場に対する抵抗変
化も大きい、セラミック超電導体磁気抵抗素子を開発し
た。（特願昭62−189347など。） 上記の開発したセラミック超電導体磁気抵抗素子の、セ
ラミック超電導体は、第３図に示すように、微細な超電
導体結晶粒子１からなり、その粒子の表面の極めて薄い
絶縁層、又は、その粒子間の弱接合２を介して、他の粒
子と結合された状態になっている。これは、微小な超電
導体の粒子間がジョセフソン接合３を構成した多結晶の
セラミック超電導体とみなすことが出来る。（第４図参
照）このような、セラミック超電導体で磁気抵抗素子
を、第５図のような、セラミック超電導体４（１×７×
0.7mm）に、電極5,6を蒸着などで作りリード線7,8を接
続して、作製する。この超電導体を、臨界温度が90K程
度のＹ−Ba−Cu−Ｏ系のセラミックで作製し、液体窒素
（77K）に入れ、電極5,6を介して定電流源（図示せず）
により、流した電流と、この磁気抵抗素子に印加した磁
場により変化した素子４の抵抗値は第６図のようになっ
た。この図のように、素子に流す電流Ｉが大きくなるほ
ど、素子が電気抵抗を発生する磁場は小さくなり、又、
磁場の増加による素子４の抵抗増加は大きくなる。<Prior Art> A conventional magnetoresistive element uses a semiconductor or a magnetic body. However, the magnetic field density and the resistance change rate, which indicate the sensitivity, are
As shown in the figure, the increase in the resistance of the magnetoresistive element with respect to the increase in the strength of the magnetic field becomes a quadratic curve, and when the strength of the magnetic field to be measured is weak, the change in resistance with respect to the magnitude B of the magnetic field is ΔR. Is small, and ΔR /
R 0 was 1% or less. (R 0 is the resistance value of the magnetoresistive element when the magnetic field is 0) A ceramic superconductor magnetoresistive element, which is an improvement of the conventional magnetoresistive element, improves sensitivity to the magnetic field, and has a large resistance change to a weak magnetic field. Was developed. (Japanese Patent Application No. 62-189347, etc.) As shown in FIG. 3, the ceramic superconductor of the above-described developed ceramic superconductor magnetoresistive element is composed of fine superconductor crystal particles 1 and It is in a state of being bonded to another particle through an extremely thin insulating layer or a weak bond 2 between the particles. This can be regarded as a polycrystalline ceramic superconductor in which Josephson junctions 3 are formed between fine superconductor particles. (See FIG. 4) A magnetic resistance element is made of such a ceramic superconductor, and a ceramic superconductor 4 (1 × 7 ×) as shown in FIG.
Electrodes 5 and 6 are made by vapor deposition etc. and lead wires 7 and 8 are connected to 0.7 mm) to make them. This superconductor is made of Y-Ba-Cu-O-based ceramic with a critical temperature of about 90K, put in liquid nitrogen (77K), and a constant current source (not shown) is placed through electrodes 5 and 6.
As a result, the resistance value of the element 4 changed by the applied current and the magnetic field applied to the magnetoresistive element was as shown in FIG. As shown in this figure, the larger the current I flowing through the element, the smaller the magnetic field that causes the element to generate electric resistance, and
The increase in the resistance of the element 4 due to the increase in the magnetic field increases.

このセラミック超電導体を用いた磁気抵抗素子は、印加
磁場が小さいとき粒子の粒界をトンネル効果で電流が流
れるので、抵抗がなく電圧は発生しない。この磁気抵抗
素子に、一定以上の小さい磁場を印加すると、そのセラ
ミック超電導体の粒子の粒界はトンネル効果の電流が流
れないようになり、電気抵抗をもつようになる。この電
気抵抗は電極5,6間に発生する電圧を測定することによ
り検出できる。この素子に抵抗が発生する磁場の大きさ
は素子に流す電流などで調整することができる。又、こ
の素子に印加する磁場の増加に対する、素子の電気抵抗
の増加率も大きくできるので、極めて敏感な磁気センサ
にすることができる。更に、この素子に外部からバイア
ス磁場を印加し感度を制御することもできる。In the magnetoresistive element using the ceramic superconductor, when the applied magnetic field is small, the current flows through the grain boundaries of the particles by the tunnel effect, so that there is no resistance and no voltage is generated. When a magnetic field smaller than a certain level is applied to this magnetoresistive element, the tunnel effect current does not flow in the grain boundaries of the particles of the ceramic superconductor, and the magnetoresistive element has an electric resistance. This electric resistance can be detected by measuring the voltage generated between the electrodes 5 and 6. The magnitude of the magnetic field generated by the resistance in this element can be adjusted by the current flowing through the element. Further, since the rate of increase of the electric resistance of the element can be increased with respect to the increase of the magnetic field applied to this element, the magnetic sensor can be made extremely sensitive. Further, the sensitivity can be controlled by applying a bias magnetic field from the outside to this element.

一方、超電導材料の磁気特性について記載された文献と
して、C.W.ChuらによるPhys.Rev.Lett.54［４］（26 Ja
n.1987）pp.405−407が知られている。この文献には、L
a−Ba−Cu−Ｏ化合物系における温度40゜K以下での超電
導現象に基づく磁気特性を評価したことが記記載されて
いる。La−Ba−Cu−Ｏ化合物の作製方法としては、酸化
ランタン（La2O3）と酸化銅（CuO）と炭酸バリウム（Ba
CO3）との混合物を、減圧下の酸素雰囲気中にて加熱保
持した後、これを粉にし、これらの工程を繰り返して、
完全に反応したこれらの混合物を加圧して円筒状とし、
先の工程と同様に減圧下の酸素雰囲気中にて焼結するも
のである。そして、上記のようにして作製したLa−Ba−
Cu−Ｏ化合物に対して、０、4.5、15、30、58.5kガウス
という非常に強い磁界を印加した場合において、40゜K
以下の温度に冷却したときの電気抵抗の変化を測定した
結果が記載されている。On the other hand, as a document describing the magnetic properties of superconducting materials, CW Chu et al., Phys. Rev. Lett. 54 [4] (26 Ja
n.1987) pp.405-407 are known. In this document, L
It is described that the magnetic properties based on the superconducting phenomenon at the temperature of 40 ° K or less in the a-Ba-Cu-O compound system were evaluated. As the method of preparing a La-Ba-CuO compound, copper oxide and lanthanum oxide (La 2 O 3) (CuO ) and barium carbonate (Ba
The mixture with CO 3 ) is heated and held in an oxygen atmosphere under reduced pressure, and then powdered, and these steps are repeated,
Pressing these completely reacted mixtures into a cylinder,
Similar to the previous step, the sintering is performed in an oxygen atmosphere under reduced pressure. Then, the La-Ba- produced as described above
When a very strong magnetic field of 0, 4.5, 15, 30, 58.5k Gauss is applied to a Cu-O compound, 40 ° K
The results of measuring the change in electrical resistance when cooled to the following temperatures are described.

しかしながら、上記文献に示されたような化合物系の超
電導体は、同文献中に示されるとおり多相（multiphas
e）を成しており、磁界に対する抵抗変化の原理につい
ても、上記文献中には、混合された相（mixed phas
e）、あるいは多相の中の一種類の相であるK2NiF4相の
影響によるものと思われる旨考案されているに過ぎず、
詳細は解明されていない。また、4.5kガウス以上という
強い磁界での電気抵抗の変化しか観察されていない。し
たがって、上記文献に示された超電導材料では、微弱な
磁界に対して高性能に抵抗変化を示す磁気抵抗素子を期
待することはできない。However, the compound-based superconductor as shown in the above-mentioned document has a multiphase (multiphas) structure as shown in the same document.
e), and the principle of resistance change with respect to a magnetic field is also described in the above literature.
e), or only to be thought to be due to the effect of one of the phases, K 2 NiF 4 phase,
The details have not been clarified. Moreover, only the change of electric resistance was observed in a strong magnetic field of 4.5 k Gauss or more. Therefore, with the superconducting material shown in the above-mentioned document, it is not possible to expect a magnetoresistive element that exhibits a high resistance change with respect to a weak magnetic field.

＜発明が解決しようとする問題点＞ セラミック超電導体の磁気抵抗素子による磁気センサ
は、従来の磁気抵抗素子と異なる原理によって動作する
ので、磁気感度を格段に高くすることができる。しか
し、感度が高いために素子４に流す電流によって発生し
た磁場によっても測定する磁場を変えてしまい、測定値
に誤差を生じることがある。<Problems to be Solved by the Invention> A magnetic sensor using a magnetoresistive element of a ceramic superconductor operates according to a principle different from that of a conventional magnetoresistive element, so that the magnetic sensitivity can be remarkably increased. However, since the sensitivity is high, the magnetic field to be measured may be changed by the magnetic field generated by the current flowing through the element 4, which may cause an error in the measured value.

磁気センサの感度を高くして、磁場を正確に測定するた
めには、センサに流す電流を小さくすること、外部から
補助のバイアス磁場を印加しないこと、が望しい。以上
の条件をみたした上、磁気センサとしての感度を高くし
ておくためには、セラミック超電導体を細く、長くして
抵抗が発生したときの抵抗値を大きくしておく必要があ
る。しかし、磁気センサを長くすると、そこを流れる電
流によりその長さに比例した磁場を発生する。In order to increase the sensitivity of the magnetic sensor and accurately measure the magnetic field, it is desirable to reduce the current flowing through the sensor and not apply an auxiliary bias magnetic field from the outside. In addition to the above conditions, in order to increase the sensitivity of the magnetic sensor, it is necessary to make the ceramic superconductor thin and long to increase the resistance value when resistance is generated. However, when the magnetic sensor is lengthened, a current flowing therethrough generates a magnetic field proportional to its length.

本発明は、この磁気抵抗素子による磁場が、素子の外部
の磁場を変えない構成にすることにより、微小な磁場も
高精度で測定することができるセラミック超電導体磁気
抵抗素子を提供することを目的にしたものである。It is an object of the present invention to provide a ceramic superconductor magnetoresistive element capable of measuring a minute magnetic field with high accuracy by using a configuration in which the magnetic field generated by the magnetoresistive element does not change the magnetic field outside the element. It is the one.

＜問題点を解決するための手段＞ 本発明は、多数の結晶粒界を有し、超電導を示す結晶粒
が互いに電気的に弱結合しているセラミック超電導体
を、間隔を介し接近して並行に対を成して隣り合うよう
に配置し、かつ、磁気抵抗素子として流れる電流が互に
反対方向になる接続にした構成の超電導体磁気抵抗素子
である。<Means for Solving Problems> In the present invention, ceramic superconductors having a large number of crystal grain boundaries, in which crystal grains exhibiting superconductivity are electrically weakly coupled to each other, are closely spaced and parallel to each other. Is a superconducting magnetoresistive element having a structure in which the currents flowing as the magnetoresistive elements are connected in opposite directions.

上記のようなセラミック超電導体を、間隔を介し隣り合
った対をなすように形成するために、基板上に作製した
セラミック超電導体膜をエッチングにより部分的に除去
するか、又は、その作製した膜を部分的に、レーザービ
ーム，電子ビーム等のエネルギービームを照射すること
により、その部分を常電導体に変えて、目的の超電導体
パターンを形成する方法を使用することができる。In order to form the ceramic superconductor as described above so as to form a pair adjacent to each other with a gap, the ceramic superconductor film formed on the substrate is partially removed by etching, or the formed film. It is possible to use a method of partially irradiating an energy beam such as a laser beam or an electron beam to change the portion into a normal conductor to form a desired superconductor pattern.

又、２枚の基板に重ねたとき同じ配置になるパターンの
線状セラミック超電導体を作製し、絶縁膜を介して積層
し上下のパターンを一致させ、上下の素子の一端を前記
絶縁膜のスルーホールを介して電気的に接続すること
で、目的の間隔を介し隣り合った線状素子を極めて近接
した状態に構成することができる。In addition, linear ceramic superconductors having the same pattern when they are stacked on two substrates are produced, and the upper and lower patterns are made to match by stacking them with an insulating film interposed therebetween, and one end of the upper and lower elements is made to pass through the insulating film. By electrically connecting through the holes, it is possible to configure the linear elements that are adjacent to each other with a desired spacing in an extremely close state.

＜作用＞ 磁場に対する感度の高い、セラミック超電導体磁気抵抗
素子を、非常に近接させた無誘導構造といわれる構成に
して、この磁気抵抗素子の電流による、素子の外部への
磁場発生をなくすことができるので、微弱な磁場を、正
確に測定することができる。又、この磁気抵抗素子がそ
の電流によって外部に磁場を作らないので、他の磁気セ
ンサを近接した位置に設定しても、磁気センサ間で干渉
して測定に誤差を生じることはなくなる。<Operation> A ceramic superconductor magnetoresistive element having high sensitivity to a magnetic field is formed in a structure called a non-inductive structure in which the elements are very close to each other, and the generation of a magnetic field to the outside of the element by the current of the magnetoresistive element can be eliminated. Therefore, the weak magnetic field can be accurately measured. Further, since this magnetic resistance element does not generate a magnetic field outside due to the current, even if another magnetic sensor is set in a close position, it does not cause an error in measurement due to interference between the magnetic sensors.

又、本発明の構成にすれば、素子のインダクタンスをな
くすことができるので、非常に高い周波数迄測定するこ
とができる。Further, according to the configuration of the present invention, the inductance of the element can be eliminated, so that it is possible to measure up to a very high frequency.

＜実施例＞ 本発明の実施例を、図面を参照しながら説明する。<Example> An example of the present invention will be described with reference to the drawings.

第１図は、本発明のセラミック超電導体の基本構成を示
した図で、セラミック超電導体としては臨界温度が90〜
100Kのイットリウムーバリウム−銅の酸化物（Ｙ−Ba−
Cu−Ｏ）を使用した。この超電導体は耐熱基板であるア
ルミナ（Al2O3）基板にスパッタリング法で約10μｍの
膜を作り、空気中で900℃に加熱した後、徐冷する熱処
理で、YBa2Cu3O7−δ（Ｏ＜δ＜１）の組成比にした。
作製したＹ−Ba−Cu−Ｏ膜をエッチングにより第１図の
形状の素子４にし、蒸着により、この超電導体との密着
性がよいチタン（Ti）の電極5,6を作製し、そこにリー
ド線7,8を接続した。FIG. 1 is a diagram showing a basic structure of a ceramic superconductor of the present invention, which has a critical temperature of 90 to 90 for a ceramic superconductor.
100K yttrium-barium-copper oxide (Y-Ba-
Cu-O) was used. This superconductor is a heat-resistant substrate made of alumina (Al 2 O 3 ) and has a film thickness of about 10 μm formed by a sputtering method. The film is heated to 900 ° C. in air and then slowly cooled to produce YBa 2 Cu 3 O 7 −. The composition ratio was δ (O <δ <1).
The produced Y-Ba-Cu-O film was etched to form the element 4 having the shape shown in FIG. 1, and titanium (Ti) electrodes 5 and 6 having good adhesion to the superconductor were produced by vapor deposition, and the element was formed there. Lead wires 7 and 8 were connected.

この超電導体磁気抵抗素子は、この実施例の方法による
以外に種々の作製方法を使用することができる。例え
ば、膜の作製には、真空蒸着法や、CVD法、又は、その
構成元素の化合物を水溶液にして、加熱した基板の上に
スプレーする方法も使うことができる。シリカやチタン
酸バリウムなどの基板を使うこともできる。For this superconductor magnetoresistive element, various manufacturing methods can be used other than the method of this embodiment. For example, in order to form a film, a vacuum vapor deposition method, a CVD method, or a method in which a compound of its constituent elements is made into an aqueous solution and sprayed on a heated substrate can be used. Substrates such as silica or barium titanate can also be used.

セラミック超電導体磁気抵抗素子の感度の特性を決める
のは、それを構成している粒子の粒径と、その粒子の間
の粒界の状態によると考えられる。It is considered that the sensitivity characteristic of the ceramic superconductor magnetoresistive element is determined by the particle size of the particles forming the magnetoresistive element and the state of the grain boundary between the particles.

セラミック超電導体を、焼成で作製するときは、原料に
なる粉末の酸化イットリウムY2O3,炭酸バリウムBaCO3,
酸化銅CuOを所定量秤量し、充分混合してから約900℃で
焼成してほぼ目的のセラミックにし、更に、粉砕し微粒
子にし混合・プレス成形し、約1000℃で本焼成してい
た。このセラミックの粒径は、本焼成の前に粉砕したと
きの微粒子の径によってほぼ決まっていた。従って、焼
成法で作るときは、１回目の焼成物を、粒径が約μｍの
微粒子になるよう粉砕していた。この粉砕した粒径とセ
ラミック超電導体磁気抵抗素子の感度との間の相関関係
は確認している。When producing a ceramic superconductor by firing, yttrium oxide Y 2 O 3 , barium carbonate BaCO 3 ,
A predetermined amount of copper oxide CuO was weighed, sufficiently mixed, and then fired at about 900 ° C. to obtain an almost intended ceramic, further pulverized into fine particles, mixed and press-molded, and then main-fired at about 1000 ° C. The particle diameter of this ceramic was almost determined by the diameter of the fine particles when crushed before the main firing. Therefore, when it is produced by the firing method, the first-time fired product is pulverized into fine particles having a particle size of about μm. The correlation between this crushed particle size and the sensitivity of the ceramic superconductor magnetoresistive element has been confirmed.

本発明の実施例で、基板の上にセラミック超電導体の膜
を作製するときは、基板にその材料をデポジットしたと
きの基板の温度によって殆んど作製した膜を構成する粒
子の粒径が決まると考えられる。When a ceramic superconductor film is formed on a substrate in the embodiments of the present invention, the temperature of the substrate when the material is deposited on the substrate almost determines the particle size of the particles forming the film. it is conceivable that.

膜状に形成した超電導体は、焼結によってバルク状に作
製した超電導体より、熱処理の雰囲気や温度による効果
が大きい。The film-shaped superconductor has a greater effect of the heat treatment atmosphere and temperature than the bulk-shaped superconductor produced by sintering.

本実施例のセラミック超電導体膜は、基板を300〜400℃
に加熱し、スパッタリングで膜を作製した。この膜を空
気中約950℃で加熱し、徐冷することにより超電導体の
膜にした。素子のパターン形成も、作製した膜にArなど
不活性ガスのスパッタリング・エッチや、超電導体膜に
レーザビーム、電子ビーム、又は、イオンビーム等のエ
ネルギー、ビームを照射し、その照射された部分の状態
を変えて常電導体にすることにより、目的の超電導体の
パターンを形成することもできる。The ceramic superconducting film of this example has a substrate temperature of 300 to 400 ° C.
Then, the film was formed by sputtering. This film was heated in air at about 950 ° C. and gradually cooled to form a superconductor film. The patterning of the element is also performed by sputtering / etching the prepared film with an inert gas such as Ar, or by irradiating the superconducting film with energy such as a laser beam, an electron beam, or an ion beam, and the irradiated portion. It is also possible to form a desired superconductor pattern by changing the state to a normal conductor.

第７図は、本発明の説明のために第１図の素子の一辺の
動作を説明したもので、線状に形成したＹ−Ba−Cu−Ｏ
超電導体４に、電極5,6と、リード線7,8をつけている。
この素子を磁場Ｂの中に設置し、電流Ｉを流して磁場の
測定をするとき、その電流Ｉによって発生する磁場Ｂ′
によって、測定すべき磁場Ｂに磁場Ｂ′が加わり、測定
した値に誤差を生じた。この誤差は、測定した磁気抵抗
素子の感度が高くなるほど、大きくなり問題になってく
る。FIG. 7 illustrates the operation of one side of the device shown in FIG. 1 for the purpose of explaining the present invention. Y-Ba-Cu-O formed into a linear shape is shown.
Electrodes 5 and 6 and lead wires 7 and 8 are attached to the superconductor 4.
When this element is installed in a magnetic field B and a current I is applied to measure the magnetic field, a magnetic field B'generated by the current I is generated.
As a result, the magnetic field B ′ was added to the magnetic field B to be measured, and an error occurred in the measured value. This error becomes more serious as the measured sensitivity of the magnetoresistive element increases.

本発明の実施例の第１図の形状にした磁気抵抗素子は、
リード線７から電極５を通って、流れる電流Ｉは、その
折り返し点迄と、折り返し点から電極６リード線７に流
れる電流が、接近して反対方向に流れるため、その電流
によって発生する磁場は、互に打ち消し合い外部へ磁場
を発生させないので、測定する磁場Ｂの分布を乱すこと
はなく、素子４も正確に磁場Ｂを測定することができ
る。The magnetoresistive element having the shape shown in FIG. 1 of the embodiment of the present invention is
The current I flowing from the lead wire 7 through the electrode 5 reaches the turnaround point, and the current flowing from the turnaround point to the lead wire 7 of the electrode 6 approaches and flows in the opposite direction. Therefore, the magnetic field generated by the current is Since they do not cancel each other out to generate a magnetic field to the outside, the distribution of the magnetic field B to be measured is not disturbed, and the element 4 can also accurately measure the magnetic field B.

本実施例のよう実施した、セラミック超電導体磁気抵抗
素子は、薄い膜で作製でき、又、ホトリソグラフの技術
を使えば、エッチングによって非常に微細なパターンも
正確に作ることができる。The ceramic superconductor magnetoresistive element implemented as in this example can be made of a thin film, and if the photolithographic technique is used, a very fine pattern can be accurately made by etching.

膜厚を10μｍにしても、100μｍの幅のパターンの超電
導体磁気センサを作製することができる。従って、本発
明の実施例を使った小型の磁気抵抗素子により、微細な
場所の測定が可能になり、又、この磁気抵抗素子は、そ
の電流による磁場を発生しないので、接近させて測定し
ても、相互に影響しあうことはない。従って、磁場の分
布、及び、その時間的変化、狭い場所などでの測定に使
用することができる。Even if the film thickness is 10 μm, a superconductor magnetic sensor having a pattern with a width of 100 μm can be manufactured. Therefore, a small-sized magnetoresistive element using the embodiment of the present invention enables measurement of a fine location. Further, since this magnetoresistive element does not generate a magnetic field due to its current, it is possible to measure closely. However, they do not affect each other. Therefore, it can be used for the distribution of the magnetic field, its temporal change, and measurement in a narrow place.

第８図は、本発明の、第２の実施例の磁気抵抗素子のパ
ターンを示した図である。FIG. 8 is a diagram showing a pattern of the magnetoresistive element according to the second embodiment of the present invention.

この第２の実施例は第１の実施例のパターンを４回並例
にしたパターンである。このパターンにより第１の実施
例パターンより、素子の長さを４倍以上にすることがで
きるので、素子の厚さや幅を同じにし、同じ電流を流し
ても、４倍の出力電圧を得ることができる。この第２の
実施例でも無誘導構造であるから、出力電圧を大きくで
きること以外は、第１の実施例と同じ効果が得られる。
なお、このパターンのくり返し回数は、設計によって、
任意に変えることができる。又、この素子作製は第１の
実施例の方法を使うことができる。The second embodiment is a pattern in which the pattern of the first embodiment is arranged four times in parallel. With this pattern, the length of the element can be four times or more that of the pattern of the first embodiment. Therefore, even if the same thickness and width of the element are applied and the same current is applied, four times the output voltage can be obtained. You can Since the second embodiment also has the non-inductive structure, the same effect as that of the first embodiment can be obtained except that the output voltage can be increased.
The number of times this pattern is repeated depends on the design.
It can be changed arbitrarily. In addition, the method of the first embodiment can be used for manufacturing this element.

第９図は、本発明の第３実施例のパターンを示した図
で、このパターンは第１の実施例の線状の並行素子を折
り曲げたパターンで、第１の実施例の約５倍の長さの素
子を形成している。以上の実施例については、基板の図
示を省略した。FIG. 9 is a diagram showing a pattern of the third embodiment of the present invention. This pattern is a pattern obtained by bending the linear parallel elements of the first embodiment, and is about 5 times as large as that of the first embodiment. Forming elements of length. In the above examples, the illustration of the substrate is omitted.

以上の第２、及び、第３の実施例に於ても、第１の実施
例で説明したように、線状のセラミック超電導体の素子
４、及び電極5,6を作製した。電極には、リード線を接
続して、測定する。リード線7,8が短いときは、１本の
リード線で、電流と測定する電圧リードを兼用させるこ
とができるが、このリード線が長くなるときは、リード
線7,8をそれぞれ２本にして電流リード線と、電圧リー
ド線を別にした。In the second and third embodiments described above, the linear ceramic superconductor element 4 and the electrodes 5 and 6 were produced as described in the first embodiment. Lead wires are connected to the electrodes for measurement. When the lead wires 7 and 8 are short, one lead wire can be used as both the current and the voltage lead to be measured, but when the lead wires are long, use two lead wires 7 and 8 respectively. Separated the current lead wire and the voltage lead wire.

以上の実施例における、セラミック超電導体の膜厚、線
状素子の幅、長さ、及び、そのパターンの繰り返し数は
大きく変えることができる。膜厚も１μｍ〜数十μｍの
間で作製でき、線幅も10μｍまでの細さにできる。In the above examples, the thickness of the ceramic superconductor, the width and length of the linear element, and the number of repetitions of the pattern can be greatly changed. The film thickness can be produced between 1 μm and several tens of μm, and the line width can be made as thin as 10 μm.

以上で説明した、磁気抵抗素子は電極5,6にリード線7,8
を接続して使用するが、このリード線を流れる電流によ
り、測定する磁場を乱す磁場を発生しないようにするた
め、電極５と６は接近した位置に配置し、リード線も、
平行に近接させた構成にした。As explained above, the magnetoresistive element has the electrodes 5, 6 with the lead wires 7, 8
The electrodes 5 and 6 are placed close to each other so that the magnetic field that disturbs the magnetic field to be measured is not generated by the current flowing through this lead wire.
The configuration is such that they are close to each other in parallel.

第10図は、本発明を積層構造で実現した、第４の実施例
を示す図である。FIG. 10 is a diagram showing a fourth embodiment in which the present invention is realized by a laminated structure.

この例は、第１の基板９と、第２の基板10に、大きさが
同じで、電極5,6を通る線から線対称になる線状のセラ
ミック超電導体磁気抵抗素子を作製する。この素子を作
製した基板９と10を、薄い絶縁膜11を介在させて接着剤
などで積層にするが、このとき素子のパターンの一端
は、前記の絶縁膜にスルーホールを作り、その点で上下
の素子を接続させ、そのパターンの他の一部には、リー
ド線を接続するための電極5,6を作製した。この実施例
では、第２の基板10の電極部にスルーホールを設け、パ
ターンの反対側に電極６を構成した。この第３の実施例
の方法により、その磁気抵抗素子は、ほぼ任意のパター
ンにすることができ、前の実施例より線状素子を密なパ
ターンにすることができるが、最大の特徴は、上下で電
流が反対方向に流れる線状素子を、極めて接近させ、そ
のパターンの全ての点で、前記の電流による磁場を完全
に打ち消す構成になることである。この例の、線状磁気
抵抗素子も、第１の実施例で説明した方法によって作製
することができる。絶縁膜も酸化物であるシリカなどを
蒸着して作製すれば0.1μｍ程度にすることも可能であ
る。In this example, a linear ceramic superconductor magnetoresistive element having the same size and having line symmetry with respect to a line passing through the electrodes 5 and 6 is manufactured on the first substrate 9 and the second substrate 10. Substrates 9 and 10 on which this element is manufactured are laminated with an adhesive or the like with a thin insulating film 11 interposed. At this time, at one end of the pattern of the element, a through hole is formed in the above-mentioned insulating film. The upper and lower elements were connected, and electrodes 5 and 6 for connecting lead wires were formed on the other part of the pattern. In this embodiment, a through hole is provided in the electrode portion of the second substrate 10 and the electrode 6 is formed on the opposite side of the pattern. According to the method of the third embodiment, the magnetoresistive element can be formed in almost any pattern, and the linear element can be formed in a denser pattern than in the previous embodiment. The linear elements in which the currents flow in the opposite directions in the upper and lower directions are extremely close to each other, and the magnetic field due to the current is completely canceled at all points of the pattern. The linear magnetoresistive element of this example can also be manufactured by the method described in the first embodiment. The insulating film can be formed to have a thickness of about 0.1 μm by vapor-depositing silica, which is an oxide.

次に、本発明の効果を顕著に示す、第５の実施例につい
て説明する。セラミック超電導体の組成元素の化合物を
水溶液にして、スプレーパイロリシス法により耐熱性の
セラミック基板上に、厚さが約10μｍの厚膜から成る超
電導体を作製し、第12図に示したように、対を成す線状
の２本が間隔を介し非常に近接して隣り合う折れ曲がり
形状に構成した。第12図において、４は第５の実施例の
磁気抵抗素子であり、５と６とは電流端子であり、Ｅは
磁気抵抗素子４に流す電流Ｉの電流源である。13と14と
は磁気抵抗素子４の電圧出力電極で、電圧計Ｖに接続さ
れている。この第５の実施例の磁気抵抗素子について、
磁場の印加に対する抵抗値変化の特性を第13図に示す。Next, a fifth embodiment will be described in which the effect of the present invention is remarkably exhibited. The compound of the composition elements of the ceramic superconductor was made into an aqueous solution, and a superconductor consisting of a thick film with a thickness of about 10 μm was prepared on a heat-resistant ceramic substrate by spray pyrolysis method, and as shown in FIG. , Two linear wires forming a pair are arranged so as to be adjacent to each other very closely to each other with a gap therebetween. In FIG. 12, 4 is a magnetoresistive element of the fifth embodiment, 5 and 6 are current terminals, and E is a current source of a current I flowing through the magnetoresistive element 4. Reference numerals 13 and 14 denote voltage output electrodes of the magnetoresistive element 4, which are connected to the voltmeter V. Regarding the magnetoresistive element of the fifth embodiment,
Fig. 13 shows the characteristics of resistance change with respect to the application of a magnetic field.

比較のため、上記第５の実施例と同様にして作製したセ
ラミック超電導体の厚膜を用いて、第５図に示した従来
の長方形の形状に構成した磁気抵抗素子について、磁場
の印加に対する抵抗値変化の特性を第11図に示す。For comparison, a conventional magnetoresistive element having a rectangular shape shown in FIG. 5 is prepared by using a thick film of a ceramic superconductor produced in the same manner as in the fifth embodiment, and the resistance to application of a magnetic field is reduced. The characteristics of the change in value are shown in FIG.

本発明の第５の実施例の特性を示す第13図を第11図と比
較すると、第11図に示したものでは数ガウス程度の磁場
に対してしか電気抵抗を発生していないが、第５の実施
例の磁気抵抗素子によれば10e以下の磁場に対しても電
気抵抗を生じており、このような極めて微弱な磁場をも
検出可能であることがわかる。更に、磁場の印加に対す
る抵抗値変化は、第13図に示した第５の実施例では、第
11図に示したものより、２桁以上も大きな電気抵抗を示
している。従って、本願発明によれば、従来のものより
極めて微弱な磁場を、大きな出力で、非常に高性能に検
出することできる。Comparing FIG. 13 showing the characteristics of the fifth embodiment of the present invention with FIG. 11, the one shown in FIG. 11 generates an electric resistance only for a magnetic field of about several Gauss. According to the magnetoresistive element of the fifth embodiment, an electric resistance is generated even with respect to a magnetic field of 10e or less, and it is understood that such an extremely weak magnetic field can be detected. Furthermore, the change in resistance with respect to the application of the magnetic field is the same as that in the fifth embodiment shown in FIG.
The electrical resistance is more than two orders of magnitude higher than that shown in Fig. 11. Therefore, according to the present invention, it is possible to detect a magnetic field that is extremely weaker than the conventional one with a large output and with extremely high performance.

また、第11図のものでは、外部からの印加磁場の大きさ
が一定であっても、流す電流の大きさに依存して抵抗値
が変化しているのに対して、第13図に示すように、第５
の実施例の磁気抵抗素子では、抵抗値は流す電流の大き
さが、0.1mAと0.01mAとで変化しておらず、他の電流値
に対しても抵抗値が全く変化しないことがわかった。こ
のように、抵抗値が電流地に依存しないことの理由は明
確ではないが、実験により確認している。従って、第12
図の形状の磁気抵抗素子４は容易にS/N比のよい交流駆
動で使用することができる。Also, in the case of FIG. 11, the resistance value changes depending on the magnitude of the flowing current even if the magnitude of the magnetic field applied from the outside is constant, whereas in FIG. Like, the fifth
In the magnetoresistive element of Example, it was found that the resistance value did not change at the magnitude of the current flowing between 0.1 mA and 0.01 mA, and the resistance value did not change at all for other current values. . Thus, the reason why the resistance value does not depend on the current location is not clear, but it has been confirmed by experiments. Therefore, the 12th
The magnetoresistive element 4 having the shape shown in the figure can be easily used by AC driving with a good S / N ratio.

＜発明の効果＞ 以上のように本発明のセラミック超電導体磁気抵抗素子
は、多数の結晶粒界を有し超電導を示す結晶粒が互いに
電気的に弱結合しているセラミック超電導体から構成さ
れ、更にこのセラミック超電導体を、間隔を介して隣り
合うの対を形成するように配置し、その対のセラミック
超電導体に方向が反対で、かつ、同じ大きさの電流が流
れる構成としている。よって、本発明の超電導体磁気抵
抗素子を磁気センサとして応用すれば、10e以下という
非常に微弱な磁場に対しても、大きな電気抵抗の変化を
示すことが可能であるので、磁気に対し非常に高い感度
を持つセンサが実現できる。また、素子の抵抗の発生、
又は、抵抗の変化と感度調整のために素子に流す電流に
流す電流によって外部の磁場を乱すことがないので、交
流駆動が可能となり、S/N比を大きく向上させることが
でき、従来の磁気抵抗素子とは比較にならない程高性能
な磁気センサを実現することができる。<Effects of the Invention> As described above, the ceramic superconductor magnetoresistive element of the present invention is composed of ceramic superconductors in which crystal grains having a large number of crystal grain boundaries and exhibiting superconductivity are electrically weakly coupled to each other. Further, the ceramic superconductors are arranged so as to form a pair adjacent to each other with a space therebetween, and the ceramic superconductors of the pair are configured so that currents of opposite directions and of the same magnitude flow. Therefore, if the superconductor magnetoresistive element of the present invention is applied as a magnetic sensor, it is possible to show a large change in electric resistance even with a very weak magnetic field of 10e or less, and therefore, it is very effective against magnetism. A sensor with high sensitivity can be realized. Also, the generation of the resistance of the element,
Alternatively, since the external magnetic field is not disturbed by the current flowing through the element for changing the resistance and adjusting the sensitivity, AC driving becomes possible, and the S / N ratio can be greatly improved. It is possible to realize a high-performance magnetic sensor that is incomparable to a resistance element.

さらに、本発明によるセラミック超電導体磁気抵抗素子
は、C.W.ChuらによるPhys. Rev. Lett.58［４］（26 Ja
n. 1987）pp.405−407の文献に示されたようなK2NiF4相
を含む多相のLa−Ba−Cu−Ｏ化合物系超電導材料とは、
磁界による電気抵抗の変化を生じる原理が異なるもので
ので、上記文献では、4.5kガウス以上という非常に強い
磁界を印加した状態でしか超電導現象による電気抵抗の
変化を観察されていないが、本発明に用いるセラミック
超電導磁気抵抗素子では、10e以下という微弱な磁界に
対して抵抗変化を示すことができ、上記文献からは到底
予想もできないような高性能の超電導磁気抵抗素子であ
る。Furthermore, the ceramic superconductor magnetoresistive element according to the present invention is described by CW Chu et al. In Phys. Rev. Lett. 58 [4] (26 Ja
n. 1987) and the multiphase La-Ba-Cu-O compound superconducting material containing pp.405-407 K 2 NiF 4 phases as shown in the literature,
Since the principle of causing a change in electric resistance due to a magnetic field is different, in the above literature, a change in electric resistance due to a superconducting phenomenon is observed only in a state where a very strong magnetic field of 4.5 k Gauss or more is applied. The ceramic superconducting magnetoresistive element used for is a high-performance superconducting magnetoresistive element that can exhibit a resistance change with a weak magnetic field of 10e or less and cannot be predicted from the above literature.

従って、本発明によよる超電導体磁気抵抗素子を用いた
磁気センサによれば、この磁気センサに流す電流によっ
て、広い範囲の磁場を正確に測定することができる。Therefore, according to the magnetic sensor using the superconductor magnetoresistive element according to the present invention, the magnetic field in a wide range can be accurately measured by the current passed through the magnetic sensor.

又、本発明による超電導体磁気抵抗素子を用いた磁気セ
ンサは、膜作製技術などによって小型化できる。従っ
て、安定な特性を得ることが出来種々の分野に於て、極
めて効果的な磁場測定をすることができるセラミック超
電導体磁気抵抗素子を用いた磁気センサになる。Further, the magnetic sensor using the superconductor magnetoresistive element according to the present invention can be miniaturized by a film forming technique or the like. Therefore, it becomes a magnetic sensor using a ceramic superconductor magnetoresistive element capable of obtaining stable characteristics and performing extremely effective magnetic field measurement in various fields.

【図面の簡単な説明】[Brief description of drawings]

第１図は本発明の磁気抵抗素子の構成を示した斜視図、
第２図は、従来の磁気抵抗素子の特性を示したグラフ
図、第３図はセラミック超電導体の構造を示した拡大
図、第４図はセラミック超電導体の電気的等価図、第５
図は従来の超電導体磁気抵抗素子の斜視図、第６図は第
５図の素子の特性を示したグラフ図、第７図は線状磁気
抵抗素子と磁場の関係を示した斜視図、第８図は本発明
の第２の実施例のパターンを示した図、第９図は本発明
の第３の実施例のパターンを示した図、第10図は本発明
の第４の実施例を示した斜視図、第11図は厚膜線状長方
形磁気抵抗素子の特性を示すグラフ図、第12図は本発明
の第５の実施例の構造図、第13図は本発明の磁気抵抗素
子の特性を示したグラフ図である。 １は超電導体結晶粒子、２は粒界、３はジョセフソン結
合、４は磁気抵抗素子、５と６は電極、７と８はリード
線、９と10は基板、13と14は電圧出力電極である。FIG. 1 is a perspective view showing the structure of a magnetoresistive element of the present invention,
FIG. 2 is a graph showing characteristics of a conventional magnetoresistive element, FIG. 3 is an enlarged view showing a structure of a ceramic superconductor, FIG. 4 is an electrical equivalent diagram of the ceramic superconductor, and FIG.
FIG. 6 is a perspective view of a conventional superconductor magnetoresistive element, FIG. 6 is a graph showing characteristics of the element of FIG. 5, FIG. 7 is a perspective view showing a relationship between a linear magnetoresistive element and a magnetic field, 8 shows the pattern of the second embodiment of the present invention, FIG. 9 shows the pattern of the third embodiment of the present invention, and FIG. 10 shows the fourth embodiment of the present invention. The perspective view shown in FIG. 11, FIG. 11 is a graph showing the characteristics of the thick film linear rectangular magnetoresistive element, FIG. 12 is a structural view of the fifth embodiment of the present invention, and FIG. 13 is the magnetoresistive element of the present invention. It is a graph showing the characteristics of. 1 is a superconductor crystal grain, 2 is a grain boundary, 3 is Josephson coupling, 4 is a magnetoresistive element, 5 and 6 are electrodes, 7 and 8 are lead wires, 9 and 10 are substrates, 13 and 14 are voltage output electrodes. Is.

Claims (4)

【特許請求の範囲】[Claims] 【請求項１】多数の結晶粒界を有し超電導を示す結晶粒
が互いに電気的に弱結合しているセラミック超電導体
を、間隔を介して隣り合う対を形成するように配置し、
その対のセラミック超電導体に方向が反対で、かつ、同
じ大きさの電流が流れる構成にしたことを特徴とする超
電導体磁気抵抗素子。1. A ceramic superconductor in which crystal grains having a large number of crystal grain boundaries and exhibiting superconductivity are electrically weakly coupled to each other is arranged so as to form a pair adjacent to each other with a gap,
A superconductor magnetoresistive element, characterized in that the pair of ceramic superconductors have opposite directions and currents of the same magnitude flow. 【請求項２】前記対構成のセラミック超電導体を、一方
の端部で接続した折れ曲がり形状にしたことを特徴とす
る特許請求の範囲第１項記載の超電導体磁気抵抗素子。2. The superconductor magnetoresistive element according to claim 1, wherein the paired ceramic superconductors are bent to have one end connected to each other. 【請求項３】前記対構成のセラミック超電導体を、積層
構成にしたことを特徴とする特許請求の範囲第１項、又
は、第２項記載の超電導体磁気抵抗素子。3. The superconductor magnetoresistive element according to claim 1 or 2, wherein the paired ceramic superconductors have a laminated structure. 【請求項４】前記超電導体磁気抵抗素子は、基板上に作
製した、膜状のセラミック超電導体からなることを特徴
とする特許請求の範囲第１項、第２項、又は、第３項記
載の超電導体磁気抵抗素子。4. The superconductor magnetoresistive element comprises a film-shaped ceramic superconductor produced on a substrate, as claimed in claim 1, claim 2, or claim 3. Superconductor magnetoresistive element.
JP62331008A 1987-12-25 1987-12-25 Superconductor Magnetoresistive element Expired - Fee Related JPH0671101B2 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
JP62331008A JPH0671101B2 (en) 1987-12-25 1987-12-25 Superconductor Magnetoresistive element
DE3888659T DE3888659T2 (en) 1987-12-25 1988-12-23 Superconducting magnetoresistive device.
EP88312296A EP0323187B1 (en) 1987-12-25 1988-12-23 Superconductive magneto-resistive device
US07/289,312 US5126667A (en) 1987-12-25 1988-12-23 Superconductive magneto-resistive device for sensing an external magnetic field
CN 88109265 CN1022348C (en) 1987-12-25 1988-12-24 Superconductive magneto-resistive device
US07/593,898 US5227721A (en) 1987-12-25 1990-10-05 Superconductive magnetic sensor having self induced magnetic biasing

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62331008A JPH0671101B2 (en) 1987-12-25 1987-12-25 Superconductor Magnetoresistive element

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JPH0671101B2 true JPH0671101B2 (en) 1994-09-07

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JP2005085612A (en) * 2003-09-09 2005-03-31 Yokohama Tlo Co Ltd Superconducting tape conductor, manufacturing method of the same, and device equipped with the same

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BE787545A (en) * 1971-08-16 1973-02-14 Union Carbide Corp CYCLOALIPHATIC POLYOLS AND THEIR APPLICATIONS
JPS5917175A (en) * 1982-07-20 1984-01-28 Aisin Seiki Co Ltd Detecting element of magnetic field for extremely low temperature

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Ｊａｎ．Ｊ．Ａｐｐｌ．Ｐｈｙｓ．２６［５（Ｍａｙ．１９８７）ＰＰ．Ｌ７９４−Ｌ７９５
Ｐｈｙｓ．Ｒｅｖ．Ｌｅｔｔ．５８［４（２６Ｊａｎ．１９８７）ＰＰ．４０５−４０７

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