JPS63303810A - Ceramic superconductor - Google Patents
Ceramic superconductorInfo
- Publication number
- JPS63303810A JPS63303810A JP62138750A JP13875087A JPS63303810A JP S63303810 A JPS63303810 A JP S63303810A JP 62138750 A JP62138750 A JP 62138750A JP 13875087 A JP13875087 A JP 13875087A JP S63303810 A JPS63303810 A JP S63303810A
- Authority
- JP
- Japan
- Prior art keywords
- superconductor
- ceramic superconductor
- ceramic
- atoms
- octahedron
- 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.)
- Granted
Links
- 239000002887 superconductor Substances 0.000 title claims abstract description 23
- 239000000919 ceramic Substances 0.000 title claims abstract description 12
- 229910052802 copper Inorganic materials 0.000 claims abstract description 8
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 8
- 229910052711 selenium Inorganic materials 0.000 claims abstract description 6
- 229910052714 tellurium Inorganic materials 0.000 claims abstract description 6
- 229910052788 barium Inorganic materials 0.000 claims abstract description 4
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 4
- 229910052727 yttrium Inorganic materials 0.000 claims abstract description 4
- 239000010949 copper Substances 0.000 claims description 11
- 239000011669 selenium Substances 0.000 claims description 6
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 3
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 claims description 3
- 239000001301 oxygen Substances 0.000 claims description 3
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical group [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 3
- BUGBHKTXTAQXES-UHFFFAOYSA-N Selenium Chemical compound [Se] BUGBHKTXTAQXES-UHFFFAOYSA-N 0.000 claims description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims description 2
- 239000011593 sulfur Substances 0.000 claims description 2
- PORWMNRCUJJQNO-UHFFFAOYSA-N tellurium atom Chemical compound [Te] PORWMNRCUJJQNO-UHFFFAOYSA-N 0.000 claims description 2
- 239000013078 crystal Substances 0.000 abstract description 7
- 239000007788 liquid Substances 0.000 abstract description 5
- 230000000694 effects Effects 0.000 abstract description 4
- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 abstract description 2
- 125000004429 atom Chemical group 0.000 abstract 3
- QNRATNLHPGXHMA-XZHTYLCXSA-N (r)-(6-ethoxyquinolin-4-yl)-[(2s,4s,5r)-5-ethyl-1-azabicyclo[2.2.2]octan-2-yl]methanol;hydrochloride Chemical compound Cl.C([C@H]([C@H](C1)CC)C2)CN1[C@@H]2[C@H](O)C1=CC=NC2=CC=C(OCC)C=C21 QNRATNLHPGXHMA-XZHTYLCXSA-N 0.000 abstract 2
- 229910009203 Y-Ba-Cu-O Inorganic materials 0.000 abstract 2
- 238000003475 lamination Methods 0.000 abstract 1
- 125000004430 oxygen atom Chemical group O* 0.000 abstract 1
- 239000000203 mixture Substances 0.000 description 9
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000004544 sputter deposition Methods 0.000 description 4
- 238000006467 substitution reaction Methods 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 229910052692 Dysprosium Inorganic materials 0.000 description 1
- 229910052693 Europium Inorganic materials 0.000 description 1
- 229910052689 Holmium Inorganic materials 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 210000004709 eyebrow Anatomy 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229910052746 lanthanum Inorganic materials 0.000 description 1
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 229910002076 stabilized zirconia Inorganic materials 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/80—Constructional details
- H10N60/85—Superconducting active materials
- H10N60/855—Ceramic superconductors
- H10N60/857—Ceramic superconductors comprising copper oxide
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、臨界電流密度の高いセラミックス超電導体に
関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a ceramic superconductor with a high critical current density.
従来、種々のセラミックス超電導体が見出されており、
その中にあって一般式Ｙ−Ｂａ−Ｃｕ−０系の超電導体
（式中Ｙはイツトリウム、Ｂａはバリウム、Ｃｕは銅、
０は酸素）は、比較的価れた超電導特性を示すものであ
り、その標準的組成は、Ｙ＋Ｂａｚｃｕ３ｏ？−δ（δ
≒０．２）である。Various ceramic superconductors have been discovered so far,
Among them, superconductors with the general formula Y-Ba-Cu-0 (where Y is yttrium, Ba is barium, Cu is copper,
0 is oxygen) exhibits relatively good superconducting properties, and its standard composition is Y+Bazcu3o? −δ(δ
≒0.2).
−ロ
また上記の系については、Ｙの一部または全量をＥｕ、
Ｄｙ、Ｈｏなどのランタン系希土類元素で置換した組成
改良型のものが提案されている。-B Also, for the above system, some or all of Y may be replaced by Eu,
An improved composition in which lanthanum-based rare earth elements such as Dy and Ho are substituted has been proposed.
しかし上記のＹ−Ｂａ−Ｃｕ−０系を゛母体とする種々
の組成の超電導体は、いずれも超電導特性が実用的に不
十分なものである。However, superconductors of various compositions based on the above-mentioned Y-Ba-Cu-0 system have practically insufficient superconducting properties.
即ち、臨界温度（以下Ｔｃと略記）はＹ−Ｂａ−Ｃｕ−
０系において９０〜９５Ｋ、前記の組成改良型のもので
８５〜９５に程度であり、液体窒素温度の７７にで使用
するには、温度マージンが不足する欠点がある。That is, the critical temperature (hereinafter abbreviated as Tc) is Y-Ba-Cu-
0 series has a temperature of 90 to 95K, and the above-mentioned compositionally improved type has a temperature of about 85 to 95K, which has the drawback of insufficient temperature margin when used at liquid nitrogen temperature of 77K.
一方、上記超電導体の多結晶体の臨界電流密度（以下Ｊ
ｃと略記）は、液体窒素中、零磁界において、１０”Ａ
／ｃｄ程度であり、銅の液体窒素温度における電流密度
を下廻り、実用上最大の障害となっている。On the other hand, the critical current density (hereinafter J
(abbreviated as c) is 10”A in liquid nitrogen at zero magnetic field.
/cd, which is lower than the current density of copper at liquid nitrogen temperature, and is the biggest practical obstacle.
本発明は、かかる状況に鑑みなされたもので、その目的
とするところは、Ｊｃなどの超電導特性に優れたセラミ
ックス超電導体を提供することにある。The present invention was made in view of the above situation, and its purpose is to provide a ceramic superconductor having excellent superconducting properties such as Jc.
即ち本発明は、一般式Ｙ ＋ Ｂ ａ ｚ Ｃｕ ３０
ｑ−δ−εＸεで示される組成からなることを特徴と
するものである。That is, the present invention has the general formula Y + B az Cu 30
It is characterized by having a composition represented by q-δ-εXε.
上記の一般式においてＹはイツトリウム、Ｂａはバリウ
ム、Ｃｕは銅、０は酸素、Ｘは、硫黄（Ｓ）、セレン（
Ｓｅ）、テルル（Ｔｅ）のうちの少なくとも１種、δは
ほぼ０．２、εは０．０１〜６．５の範囲において、Ｘ
がＳ、Ｓｅ、Ｔｅのうちの２種以上の場合εはそれらの
和となる。εを０．０１〜６．５に限定した理由は、ε
が０．０１以下ではＪｃの向上が認められず、またεが
６．５を超えるとＪｃは高い値を示すが、Ｔｃが低下す
るためである。In the above general formula, Y is yttrium, Ba is barium, Cu is copper, 0 is oxygen, and X is sulfur (S), selenium (
Se), tellurium (Te), δ is approximately 0.2, ε is in the range of 0.01 to 6.5,
is two or more of S, Se, and Te, ε is the sum of them. The reason why ε is limited to 0.01 to 6.5 is that ε
When ε is 0.01 or less, no improvement in Jc is observed, and when ε exceeds 6.5, Jc shows a high value, but Tc decreases.
〔作用〕
Ｙ＋ＢａｚＣｕｓＯｔ−δ−εＸεの組成からなるＹ−
Ｂａ−Ｃｕ−０系の超電導体は、１個のＣｕ原子のまわ
りを６個の０原子が八面体状にとりかこみ、この八面体
が二次元の層を形成し、この層が積層し、この眉間にＹ
とＢａの原子が分布した層状ペロブスカイト型と称され
る構造のものである。[Operation] Y- consisting of the composition Y+BazCusOt-δ-εXε
In the Ba-Cu-0 system superconductor, one Cu atom is surrounded by six 0 atoms in an octahedral shape, and these octahedrons form a two-dimensional layer, and these layers are stacked. Y between eyebrows
It has a structure called a layered perovskite type in which atoms of and Ba are distributed.
この八面体の結晶構造は、通常斜方晶と正方晶とが混在
しており、Ｙ−Ｂａ−Ｃｕ−０系にあっては、斜方晶が
超電導体となる。This octahedral crystal structure usually includes a mixture of orthorhombic and tetragonal systems, and in the Y-Ba-Cu-0 system, the orthorhombic system is a superconductor.
本発明は、Ｙ−Ｂａ−Ｃｕ−０系超電導体の０原子の一
部ないし大部分がＳ、Ｓｅ、Ｔｅの少なくとも１種の原
子で置換された構造のものであり、上記のＳ、Ｓｅ、Ｔ
ｅ原子は、いずれも０原子と同じ■、族に属し、０原子
と同様にＣｕ原子とイオン結合もしくは共有結合により
八面体を形成し得るものであり、この置換されたあとの
八面体が上記の超電導体となり得る斜方晶の結晶構造を
とり易いためにＴｃもしくはＪｃが向上するものと考え
られる。The present invention relates to a Y-Ba-Cu-0 based superconductor having a structure in which some or most of the zero atoms are substituted with at least one kind of atoms of S, Se, and Te. , T
All e atoms belong to the same group as the 0 atom, and like the 0 atom, they can form an octahedron with the Cu atom through ionic or covalent bonds, and the octahedron after this substitution is the above-mentioned octahedron. It is thought that Tc or Jc is improved because it is easy to adopt an orthorhombic crystal structure that can become a superconductor.
以下に本発明を実施例により具体的に説明する。 The present invention will be specifically explained below using examples.
実施例−１
Ｙ ｔ Ｏｓ、ＢａＣ０，、ＣｕＯの粉末をＹ：Ｂａ：
Ｃｕのモル比で１：２：３になるように秤量し、これを
水で混練したのち、直径約５０ｍ厚さ３閣の円盤状に成
形し、これを１ｏｏｏ”ｃで焼結してＹ。Example-1 YtOs, BaC0, CuO powder Y:Ba:
Weighed Cu so that the molar ratio was 1:2:3, kneaded it with water, formed it into a disk shape with a diameter of about 50 m and a thickness of 3 mm, and sintered it with 1 ooo"c to form a Y .
ＢａｘＣｕｓＯｔ−δの組成の超電導成形体を作成し、
またＳ粉末を直径５０■厚さ３ｍｍの円盤状に圧粉成形
し、これら２個の円盤を高周波スパッタ装置の別々のタ
ーゲットホルダーにセットし、雰囲気を３通りにかえて
、５００℃に加熱された１０閣Ｘ １０ｗＸ２＋＋ａ’
の安定化ジルコニア基板上にそれぞれ５時間スパッタリ
ングを行った。比較のためＹ。Create a superconducting molded body with a composition of BaxCusOt-δ,
In addition, the S powder was compacted into a disk shape with a diameter of 50 mm and a thickness of 3 mm, and these two disks were set in separate target holders of a high-frequency sputtering device, and the atmosphere was changed in three ways and heated to 500 °C. 10 cabinets X 10wX2++a'
Sputtering was performed on each stabilized zirconia substrate for 5 hours. Y for comparison.
Ｂａ１ＣｕｚＯｔ−δの組成の超電導成形体だけをター
ゲットに用い、スパッタリングを行った。Sputtering was performed using only a superconducting molded body having a composition of Ba1CuzOt-δ as a target.
上記の生成膜体について、膜厚、組成、Ｔｃ、Ｊｃを測
定した。Ｔｃ、Ｊｃは、四端子法により測定した。結果
は第１表に示した。The film thickness, composition, Tc, and Jc of the above produced film were measured. Tc and Jc were measured by the four-terminal method. The results are shown in Table 1.
第１表より明らかなように、本発明品（１〜３）は比較
品（４）に較べてＴｃ、Ｊｃとも高く、特にＳを０．４
．０．５含有するもの（２，３）はＪｃが十分に高く、
実用可能な値を示している。As is clear from Table 1, the products of the present invention (1 to 3) have higher Tc and Jc than the comparative product (4), and especially have S of 0.4
．． The one containing 0.5 (2,3) has a sufficiently high Jc,
It shows a practical value.
Ｓの置換量は、スパッタリングの雰囲気によってかなり
異なりＡｒガスに０□またはＨ，Ｓを混合したものは、
Ｓの置換量が多い。The amount of S replaced varies considerably depending on the sputtering atmosphere, and when Ar gas is mixed with 0□ or H and S,
The amount of S substitution is large.
実施例−２
実施例−１で得られたに３の膜体を、更に０２または／
およびＨ，Ｓ雰囲気中で７００°Ｃ２０時間の熱処理を
施した。Example-2 The film body of 3 obtained in Example-1 was further treated with 02 or/
Then, heat treatment was performed at 700° C. for 20 hours in an H, S atmosphere.
これらのサンプルについて実施例と同じ測定を行った。The same measurements as in the examples were performed on these samples.
結果を第２表に示した。The results are shown in Table 2.
第２表より明らかなように、本発明品（５〜７）は、い
ずれもＪｃが高く、特にＨｚ Ｓの存在下で上記熱処理
を施したもの（６，７）は、Ｊｃが著しく向上している
。０！雰囲気で熱処理したちの ｊは、Ｓの置換量
が減少しているが、Ｔｃ、Ｊｃとも熱処理前に近い、高
い値を示している。これは、一旦形成された斜方晶のほ
とんどがそのまま維持されているためと考えられる。As is clear from Table 2, the products of the present invention (5 to 7) all have high Jc, and in particular, the products (6, 7) subjected to the above heat treatment in the presence of Hz S have significantly improved Jc. ing. 0! After heat treatment in an atmosphere, the amount of S substitution decreased, but both Tc and Jc showed high values close to those before heat treatment. This is thought to be because most of the orthorhombic crystals once formed remain intact.
またＳのモル数が多い程、Ｔｃが低くなりＪｃが高くな
る傾向が認められる。It is also observed that the larger the number of moles of S, the lower the Tc and the higher the Jc.
従来のＹ−Ｂａ−Ｃｕ−０系の超電導体をＨ。The conventional Y-Ba-Cu-0 superconductor is H.
Ｓを含有する雰囲気中で熱処理しても、０がＳに置換さ
れた本発明の超電導体が得られるが、上記の置換は、Ｓ
の拡散に律速されるためバルク状のものは長時間を要し
適用がむずかしい。Even if heat-treated in an atmosphere containing S, the superconductor of the present invention in which 0 is substituted with S can be obtained.
Since the rate is determined by the diffusion of , it takes a long time to process bulk materials and is difficult to apply.
以上ＳをＯと置換する実施例について説明したが、Ｓｅ
、Ｔｅについても、またＳ、Ｓｅ、Ｔｅが複数で置換さ
れたものについても、Ｓと同じ効果が得られる。The embodiment in which S is replaced with O has been described above, but Se
, Te, and those in which a plurality of S, Se, and Te are substituted can obtain the same effect as S.
本発明によれば、Ｔｃが液体窒素温度を十分にと廻り、
且つＪｃが極めて高いセラミックス超電導体が得られる
ので、セラミックス超を導体の実利化において顕著な効
果を奏する。According to the present invention, Tc is sufficiently around the liquid nitrogen temperature,
In addition, since a ceramic superconductor having an extremely high Jc can be obtained, the ceramic superconductor has a remarkable effect in commercializing the ceramic superconductor as a conductor.
Claims (1)
Ｘ＿ε（式中Ｃｕは銅、Ｏは酸素、Ｙはイットリウム、
Ｂａはバリウム、Ｘは硫黄、セレン、テルルのうちの少
なくとも１種、δ≒０．２、ε＝０．０１〜６．５）で
示される組成物からなることを特徴とするセラミックス
超電導体。General formula Y_1Ba_2Cu_3O_7_-_δ_-_ε
X_ε (in the formula, Cu is copper, O is oxygen, Y is yttrium,
A ceramic superconductor characterized in that Ba is barium, X is at least one of sulfur, selenium, and tellurium, and δ≈0.2, ε=0.01 to 6.5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62138750A JPH0753576B2 (en) | 1987-06-02 | 1987-06-02 | Ceramics superconductor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62138750A JPH0753576B2 (en) | 1987-06-02 | 1987-06-02 | Ceramics superconductor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63303810A true JPS63303810A (en) | 1988-12-12 |
| JPH0753576B2 JPH0753576B2 (en) | 1995-06-07 |
Family
ID=15229308
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62138750A Expired - Lifetime JPH0753576B2 (en) | 1987-06-02 | 1987-06-02 | Ceramics superconductor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0753576B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6418917A (en) * | 1987-07-10 | 1989-01-23 | Matsushita Electric Ind Co Ltd | Superconductor |
| JPH01239004A (en) * | 1988-03-17 | 1989-09-25 | Matsushita Electric Ind Co Ltd | Oxide high-temperature superconductor and thin film superconductor therefrom and sputtering target therefor |
| JPH0251421A (en) * | 1988-08-12 | 1990-02-21 | Rikagaku Kenkyusho | Yba2cu3o7-xsey superconductor |
-
1987
- 1987-06-02 JP JP62138750A patent/JPH0753576B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6418917A (en) * | 1987-07-10 | 1989-01-23 | Matsushita Electric Ind Co Ltd | Superconductor |
| JPH01239004A (en) * | 1988-03-17 | 1989-09-25 | Matsushita Electric Ind Co Ltd | Oxide high-temperature superconductor and thin film superconductor therefrom and sputtering target therefor |
| JPH0251421A (en) * | 1988-08-12 | 1990-02-21 | Rikagaku Kenkyusho | Yba2cu3o7-xsey superconductor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0753576B2 (en) | 1995-06-07 |
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