JP2975608B2 - Insulating composition - Google Patents
Insulating compositionInfo
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- JP2975608B2 JP2975608B2 JP1088503A JP8850389A JP2975608B2 JP 2975608 B2 JP2975608 B2 JP 2975608B2 JP 1088503 A JP1088503 A JP 1088503A JP 8850389 A JP8850389 A JP 8850389A JP 2975608 B2 JP2975608 B2 JP 2975608B2
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- insulating composition
- insulating
- oxide
- layer
- superconducting
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Description
【発明の詳細な説明】 [発明の目的] (産業上の利用分野) 本発明は、超電導素子に用いられる絶縁性組成物に関
する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an insulating composition used for a superconducting element.
(従来の技術) 近年、Ba−La−Cu−O系の層状ペロブスカイト型の酸
化物が高い臨界温度を有する可能性のあることが発表さ
れて以来、各所で酸化物超電導体の研究が行われている
(Z.Phys.B Condensed Matter 64,189−193(198
6))。その中でもY−Ba−Cu−O系で代表される過剰
酸素を有する欠陥ペロブスカイト型の酸化物超電導体
は、臨界温度が90K以上と液体窒素以上の高い温度を有
することが確認されている(Phys.Rev.Lett.Vol.58、N
o.9,908−910)。(Prior Art) In recent years, since it was announced that Ba-La-Cu-O-based layered perovskite-type oxides may have a high critical temperature, research on oxide superconductors has been carried out in various places. (Z.Phys.B Condensed Matter 64,189-193 (198
6)). Among them, it has been confirmed that a defective perovskite-type oxide superconductor having excess oxygen typified by the Y-Ba-Cu-O system has a critical temperature of 90K or more and a high temperature of liquid nitrogen or more (Phys. .Rev.Lett.Vol.58, N
o.9,908-910).
さらに、1988年には、臨界温度が105KのBi−Sr−Ca−
Cu−O系の超電導酸化物が発見されるに至った(日本経
済新聞昭和63年1月22日等)。Furthermore, in 1988, the critical temperature of Bi-Sr-Ca-
Cu-O based superconducting oxides have been discovered (Nihon Keizai Shimbun, January 22, 1988).
このBi−Sr−Ca−Cu−O系の超電導酸化物は、Ba−La
−Cu−O系やY−Ba−Cu−O系の超電導酸化物に比べ
て、臨界温度が高いばかりでなく、高価な希土類元素が
不要であること、水分等に対する化学的安定性が高いこ
となどの利点があり、より優れた酸化物超電導材料であ
る。This Bi-Sr-Ca-Cu-O based superconducting oxide is Ba-La
-Compared to superconducting oxides based on -Cu-O or Y-Ba-Cu-O, not only the critical temperature is high, but also expensive rare earth elements are unnecessary, and chemical stability against moisture etc. is high. This is an excellent oxide superconducting material.
ところで、トンネル効果を利用した超電導素子は、超
高速動作が可能で消費電力も僅かであるため、コンピュ
ータの論理素子やメモリ素子等のデジタルデバイスへの
応用が進められている。そして、Nb/Aloxide/Nb接合やN
bN/MgO/NbN接合等を用いた4ビット乗算器、3Kゲートア
レイ等が試作されている。また、超電導体−半導体素子
として超電導3端子素子が試作されているが、これらの
素子はいずれも臨界温度が低い超電導体からなり、液体
ヘリウムを冷媒として用いるため、周辺技術の開発や経
済性の問題等から実用化には至っていない。By the way, superconducting elements utilizing the tunnel effect can operate at a very high speed and consume little power. Therefore, application to digital devices such as a logic element and a memory element of a computer is being promoted. And Nb / Aloxide / Nb junction and N
A 4-bit multiplier using a bN / MgO / NbN junction or the like, a 3K gate array, and the like have been prototyped. Also, superconducting three-terminal devices have been prototyped as superconductor-semiconductor devices, but all of these devices are composed of superconductors with a low critical temperature and use liquid helium as a refrigerant, so the development of peripheral technologies and economic efficiency Due to problems etc., it has not been put to practical use.
このため、高い臨界温度を有する酸化物超電導覆体を
前述の超電導素子に応用することが検討されている。For this reason, application of an oxide superconducting cover having a high critical temperature to the above-described superconducting element has been studied.
しかしながら、酸化物超電導体および絶縁性組成物を
用いて上記の超電導素子を得る場合、酸化物超電導体層
と絶縁性組成物の結晶面の整合性が悪いためここに新し
い電子の準位が生じ電荷がトラップされてジョセフソン
素子としての機能が損われるため、所望の特性を得るこ
とが困難であるという問題があった。However, when the above-described superconducting element is obtained using an oxide superconductor and an insulating composition, a new electron level is generated here because of poor matching between the oxide superconductor layer and the crystal plane of the insulating composition. Since the charge is trapped and the function as a Josephson element is impaired, there is a problem that it is difficult to obtain desired characteristics.
しかしながら、酸化物超電導体および絶縁性組成物を
用いて上記の超電導素子を得る場合、酸化物超電導体層
と絶縁性組成物の結晶面の整合性が悪いためここに新し
い電子の準位が生じ電荷がトラップされてジョセフソン
素子としての機能が損われるため、所望の特性を得るこ
とが困難であるという問題があった。However, when the above-described superconducting element is obtained using an oxide superconductor and an insulating composition, a new electron level is generated here because of poor matching between the oxide superconductor layer and the crystal plane of the insulating composition. Since the charge is trapped and the function as a Josephson element is impaired, there is a problem that it is difficult to obtain desired characteristics.
さらに、Bi系超電導体には転移温度が110K付近のBi2S
r2Ca2Cu3O10および転移温度が80K付近のBi2Sr2CaCu2O8
が知られている。しかしながら、より高いTcのBi2Sr2Ca
2Cu3O10を合成することは容易ではないという問題があ
った。これは、Bi系超電導体の結晶のb軸方向に存在す
る変調構造またはその原因である内部応力に基因してい
るためと考えられる。Furthermore, Bi-based superconductors have a Bi 2 S
r 2 Ca 2 Cu 3 O 10 and Bi 2 Sr 2 CaCu 2 O 8 with a transition temperature around 80 K
It has been known. However, higher Tc Bi 2 Sr 2 Ca
There was a problem that it was not easy to synthesize 2 Cu 3 O 10 . This is considered to be due to the modulation structure existing in the b-axis direction of the crystal of the Bi-based superconductor or the internal stress which is the cause thereof.
(発明が解決しようとする課題) このように、従来の絶縁性組成物を用いて超電導素子
を得る場合、酸化物超電導体層と絶縁性組成物の結晶面
の整合性が悪いという問題があった。さらに、転移温度
がより高いBi2Sr2Ca2Cu3O10を合成することが容易では
ないという問題があった。(Problems to be Solved by the Invention) As described above, when a superconducting element is obtained by using a conventional insulating composition, there is a problem in that the matching between the oxide superconductor layer and the crystal plane of the insulating composition is poor. Was. Further, there is a problem that it is not easy to synthesize Bi 2 Sr 2 Ca 2 Cu 3 O 10 having a higher transition temperature.
本発明はこのような課題に鑑みてなされたもので、そ
の目的とするところは、酸化物超電導体の結晶面との整
合性の良好な絶縁性組成物を提供することである。さら
に、本発明の他の目的は、変調構造の緩和または消失し
た絶縁性組成物を提供することである。The present invention has been made in view of such a problem, and an object of the present invention is to provide an insulating composition having good consistency with a crystal plane of an oxide superconductor. Still another object of the present invention is to provide an insulating composition in which the modulation structure is relaxed or eliminated.
[発明の構成] (課題を解決するための手段) 前記目的を達成するために本発明は、Bi、Sr、Ca、C
u、Oまたは、Tl、Ba、Ca、Cu、Oからなる酸化物超電
導体組成物のCaがRE(但し、REは、Nd、Sm、Eu、Gd、T
b、Dy、Ho、Er、Tm、Yb、LuおよびYから選ばれた元
素。)で置換されていることを特徴とする絶縁性組成物
である。[Constitution of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides Bi, Sr, Ca, C
In the oxide superconductor composition composed of u, O or Tl, Ba, Ca, Cu, O, Ca is RE (where RE is Nd, Sm, Eu, Gd, T
An element selected from b, Dy, Ho, Er, Tm, Yb, Lu and Y. ).
なお、Caは多少残っていてもさしつかえない。 It should be noted that even if some Ca remains.
ここで、Bi、Sr、RE、Cuまたは、Tl、Ba、RE、Cuの原
子比は、基本的には、2:2:1:2であるが、2:X:Y:Z程度の
ズレはかまわない。Here, the atomic ratio of Bi, Sr, RE, Cu or Tl, Ba, RE, Cu is basically 2: 2: 1: 2, but the deviation is about 2: X: Y: Z. It doesn't matter.
但し、1.5≦X≦2.5 0.5≦Y≦1.5 1.8≦Z≦2.5 また、本発明の絶縁性組成物は、Biの一部がPbで置換
されていてもよい。However, 1.5 ≦ X ≦ 2.5 0.5 ≦ Y ≦ 1.5 1.8 ≦ Z ≦ 2.5 In the insulating composition of the present invention, Bi may be partially substituted with Pb.
ここで、PbのBiの置換量は1.5を超えると結晶構造が
異なるため、1.5以下が好ましい。さらに、0.2〜1.0が
特に好ましい。Here, if the substitution amount of Bi in Pb exceeds 1.5, the crystal structure is different, and therefore it is preferably 1.5 or less. Further, 0.2 to 1.0 is particularly preferable.
本発明の絶縁性組成物は、超電導体素子において、絶
縁層、基板等の絶縁材料として用いることができる。The insulating composition of the present invention can be used as an insulating material for an insulating layer, a substrate and the like in a superconductor element.
本発明の絶縁性組成物を超電導体素子の絶縁層として
用いる場合について説明する。The case where the insulating composition of the present invention is used as an insulating layer of a superconductor element will be described.
絶縁性組成物は、Bi、Sr、RE、Cu等の炭酸塩、酸化
物、有機酸塩等を化学量論比で混合し、800〜900℃の温
度で焼成することにより得ることができる。The insulating composition can be obtained by mixing carbonates such as Bi, Sr, RE, and Cu, oxides, organic acid salts, and the like at a stoichiometric ratio, and firing the mixture at a temperature of 800 to 900 ° C.
なお、原料の配合比率は厳密に化学量論比である必要
はなく、10%程度の相違があっても差支えない。また、
微量のアルカリ金属化合物を添加して反応温度を低下さ
せることも可能である。The mixing ratio of the raw materials does not need to be strictly a stoichiometric ratio, and a difference of about 10% may be used. Also,
It is also possible to add a small amount of an alkali metal compound to lower the reaction temperature.
たとえばトンネル接合型のジョセフソン素子は、真空
蒸着法、マグネトロンスパッタ法、イオンビームスパッ
タ法、クラスタイオンビーム法、分子線エピタキシ法等
の物理蒸着法や、CVD、プラズマCVD等の化学気相蒸着法
により、基板上に酸化物超電導体層、絶縁層および酸化
物超電動体層を順次積層して得ることができる。For example, tunnel-junction type Josephson devices are manufactured by physical vapor deposition such as vacuum deposition, magnetron sputtering, ion beam sputtering, cluster ion beam, molecular beam epitaxy, and chemical vapor deposition such as CVD and plasma CVD. Thereby, an oxide superconductor layer, an insulating layer, and an oxide supermotor layer can be sequentially laminated on a substrate.
また、酸化物超電導体および絶縁性組成物を構成する
各金属元素を蒸気源またはターゲットとして、多元蒸着
または多元スパッタリングにより形成することも可能で
ある。酸化物超電導体がBi、Sr、Ca、Cu、Oからなり、
絶縁層がBi、Sr、RE、Cu、Oからなる場合は、酸化物超
電導体層の形成と絶縁層の形成を切替えるのに、1つの
元素だけ取り替えればよいのが作業性が良好である。Alternatively, the oxide superconductor and the metal element forming the insulating composition can be formed by multi-source evaporation or multi-source sputtering using a vapor source or a target. The oxide superconductor is made of Bi, Sr, Ca, Cu, O,
When the insulating layer is made of Bi, Sr, RE, Cu, O, the workability is good because only one element needs to be replaced to switch between the formation of the oxide superconductor layer and the formation of the insulating layer. .
酸化物超電導体層の厚さは、超電導特性を示す厚さ、
すなわち概ね100Å以上、絶縁層の厚さはトンネル効果
を阻害しない厚さ、すなわち50〜200Åであることが好
ましい。The thickness of the oxide superconductor layer is a thickness exhibiting superconducting properties,
That is, it is preferable that the thickness of the insulating layer is about 100 ° or more, that is, a thickness that does not hinder the tunnel effect, that is, 50 to 200 °.
さらに、各物質層を形成した後、必要に応じて酸素含
有雰囲気中400〜900℃で熱処理し、酸化物超電導体の酸
素空席に酸素を導入して超電導特性を向上させる。Further, after forming each material layer, if necessary, heat treatment is performed at 400 to 900 ° C. in an oxygen-containing atmosphere, and oxygen is introduced into oxygen vacancies of the oxide superconductor to improve superconductivity.
なお、同様にして超電導3端子素子や高感度磁気セン
サ等を得ることもできる。In the same manner, a superconducting three-terminal element, a high-sensitivity magnetic sensor, and the like can be obtained.
本発明の絶縁性組成物を超電導体素子の基板として用
いる場合は、単結晶基板は、通常のフラックス法、FZ
(Floating Zone)法、またはキロプロス法により育成
される。When the insulating composition of the present invention is used as a substrate of a superconductor element, a single crystal substrate is formed by a normal flux method, FZ
(Floating Zone) method or cultivated by the kilopros method.
Bi、Sr、RE、Cu、Oからなる絶縁性組成物を、フラッ
クス法で育成するときは、フラックスとして、Bi2O3とC
uOとを同時に含むフラックスを用いてもよい。When growing an insulating composition composed of Bi, Sr, RE, Cu, and O by the flux method, Bi 2 O 3 and C are used as flux.
A flux containing uO at the same time may be used.
さらに、Bi、Sr、RE、Cu、Oからなる絶縁性組成物
を、フラックス法で育成するときは、各原料陽イオンの
組成が、モル比%(β,γ,ε)で、 βBi2O3γ{(Sr,RE)O}+εCuO 但し、 5≦β≦25 20≦γ≦60 10≦ε≦60 2β+γ+ε=100 の関係を満足してもよい。Furthermore, when growing an insulating composition comprising Bi, Sr, RE, Cu, and O by the flux method, the composition of each raw material cation is represented by the molar ratio% (β, γ, ε): βBi 2 O 3 γ {(Sr, RE) O} + εCuO where 5 ≦ β ≦ 25 20 ≦ γ ≦ 60 10 ≦ ε ≦ 60 2β + γ + ε = 100 may be satisfied.
(作用) 本発明の絶縁性組成物は、酸化物超電導体と同一また
は類似の結晶構造を有し、格子定数も極めて近い値であ
るため、結晶構造が同一または類似のため界面における
整合性が良く、電荷のトラップによる特性の低下が抑止
される。(Action) The insulating composition of the present invention has the same or similar crystal structure as the oxide superconductor, and has a very close lattice constant. In addition, deterioration of characteristics due to charge trapping is suppressed.
特に、本発明の絶縁性組成物を基板として用いた場合
は、結晶構造が同一または類似であるため、基板上にエ
ピタキシャル成長させた酸化物超電導薄膜単結晶が形成
できる。In particular, when the insulating composition of the present invention is used as a substrate, since the crystal structure is the same or similar, an oxide superconducting thin film single crystal epitaxially grown on the substrate can be formed.
また、本発明の絶縁性組成物は、高温熱処理時におい
ても安定でしかも酸化物超電導体の結晶面と反応しな
い。Further, the insulating composition of the present invention is stable even during high-temperature heat treatment and does not react with the crystal plane of the oxide superconductor.
したがって、絶縁材料として本発明の絶縁性組成物を
用いた超電導素子を用いることにより、超高速動作で低
消費電力のIC、トランジスタ、高感度磁気センサ等を製
造することが可能となる。Therefore, by using a superconducting element using the insulating composition of the present invention as an insulating material, it becomes possible to manufacture an IC, a transistor, a high-sensitivity magnetic sensor, and the like, which operate at ultra-high speed and consume low power.
さらに、本発明の絶縁性組成物のBiの一部をPbで置き
換えることにより、格子定数がさらに、Bi系超電導体に
近ずく。また、本発明の絶縁性組成物の変調構造が緩和
または消失する。Further, by replacing a part of Bi in the insulating composition of the present invention with Pb, the lattice constant further approaches that of a Bi-based superconductor. Further, the modulation structure of the insulating composition of the present invention is relaxed or disappears.
本発明の絶縁性組成物の単結晶上に、Bi系超電導体薄
膜を成長させると、容易に高いTcをもつBi2Sr2Ca2Cu3O
10層が得られる。これは、本発明の絶縁性組成物におい
ては、変調構造が緩和または消失されており、その上に
エピタキシャル成長した超電導体薄膜においても、変調
構造が緩和または消失されているためと考えられる。When a Bi-based superconductor thin film is grown on a single crystal of the insulating composition of the present invention, Bi 2 Sr 2 Ca 2 Cu 3 O having a high Tc is easily obtained.
10 layers are obtained. This is presumably because the modulated structure is relaxed or eliminated in the insulating composition of the present invention, and the modulated structure is also relaxed or eliminated in the superconductor thin film epitaxially grown thereon.
さらに、このようにして得られた超電導体薄膜におい
ては、同様の理由によりシャープな超電導転移が得ら
れ、これにより、たとえば、77Kでの臨界電流の向上も
みられることがわかった。Furthermore, in the superconducting thin film thus obtained, it was found that a sharp superconducting transition was obtained for the same reason, and that, for example, an improvement in the critical current at 77K was also observed.
すなわち、本発明の絶縁性組成物を超電導体素子にお
ける絶縁材料として用いることにより容易に110Kでシャ
ープな転移を示す良好な超電導素子が得られる。That is, by using the insulating composition of the present invention as an insulating material in a superconductor element, a good superconductor element showing a sharp transition at 110 K can be easily obtained.
以上Bi系について説明したが、Tl系もBi系と同様の結
晶構造を有し同様のことが言えることは言うまでもな
い。Although the Bi system has been described above, it is needless to say that the Tl system has the same crystal structure as the Bi system, and the same can be said.
(実施例) 以下、図面に基づいて本発明の実施例について説明す
る。(Example) Hereinafter, an example of the present invention is described based on a drawing.
実施例1 第1図は、本発明の絶縁性組成物を絶縁層として用い
たトンネル接合型の酸化物超電導素子の横断面を示すも
ので、同図において酸化物超電導素子1は、基板2の上
に、Bi2Sr2Ca1Cu2Oα層3、Bi2Sr2Y1Cu2Oα層4、Bi2Sr
2Ca1Cu2Oα層5が順次積層されて構成されている。Example 1 FIG. 1 shows a cross section of a tunnel junction type oxide superconducting element using an insulating composition of the present invention as an insulating layer. In FIG. On top, Bi 2 Sr 2 Ca 1 Cu 2 O α layer 3, Bi 2 Sr 2 Y 1 Cu 2 O α layer 4, Bi 2 Sr
2 Ca 1 Cu 2 O α layers 5 are sequentially laminated.
[Bi2Sr2Ca1Cu2Oαターゲットの製造] まず、Bi2O3粉末33.5mol%、SrCO3粉末33.5mol%、Ca
CO3粉末33.5mol%、CuO粉末16.7mol%を用い、ジルコニ
アボールとともにモノポットに入れて湿式粉砕を行った
後、脱水乾燥を施し、加熱処理して仮焼し(850℃〜900
℃、24h)、さらに再度モノポットに入れて湿式粉砕を
行い、脱水乾燥を施し粒径5μm以下の粉末(超電導
体)を得た。[Production of Bi 2 Sr 2 Ca 1 Cu 2 O α target] First, 33.5 mol% of Bi 2 O 3 powder, 33.5 mol% of SrCO 3 powder, Ca
Using 33.5 mol% of CO 3 powder and 16.7 mol% of CuO powder, wet grinding is performed in a monopot together with zirconia balls, followed by dehydration drying, heat treatment and calcination (850 to 900 ° C).
C., 24 h), and again placed in a monopot for wet pulverization, followed by dehydration and drying to obtain a powder (superconductor) having a particle size of 5 μm or less.
次いで、前記原料粉末にポリビニルアルコールを加え
て造粒して造粒物を調整し、この各造粒物金型に充填
し、1000kg/cm2の圧力下で成形し、直径154mm、厚さ6.5
mmの円盤を作製した。Next, polyvinyl alcohol was added to the raw material powder to prepare granules by granulation, and each granulated product was filled into a mold and molded under a pressure of 1000 kg / cm 2 to have a diameter of 154 mm and a thickness of 6.5.
mm disks were made.
さらに、これを酸素含有雰囲気中840℃ X 24時焼成し
て、Bi2Sr2Ca1Cu2Oαで表される酸化物超電導体からな
る焼結密度が98%のターゲット材料を得た。Further, this was calcined at an oxygen-containing atmosphere 840 ° C. X 24, the sintered density of an oxide superconductor represented by Bi 2 Sr 2 Ca 1 Cu 2 O α was obtained 98% of the target material.
[Bi2Sr2Y1Cu2Oαターゲットの製造] 前述のCaCO3粉末をY2O3に代えた以外は、上記と同じ
方法で直径154mm、厚さ6.5mmの円盤状のBi2Sr2Y1Cu2Oα
で表される非導電性酸化物からなる焼結密度が98%のタ
ーゲットを製造した。[Production of Bi 2 Sr 2 Y 1 Cu 2 O α target] A disk-shaped Bi 2 Sr having a diameter of 154 mm and a thickness of 6.5 mm was formed in the same manner as described above, except that the above CaCO 3 powder was replaced with Y 2 O 3. 2 Y 1 Cu 2 O α
A target having a sintering density of 98% made of a non-conductive oxide represented by
[酸化物超電導素子(ジョセフソン素子)の製造] Bi2Sr2Ca1Cu2Oαターゲットを使用し、95mol%のアル
ゴンと5mol%の酸素からなる7Paの混合気体中で、高周
波マグネトロンスパッタにより、基板温度700℃の10×1
0×1mmのSrTiO3基板上に、厚さ1.0μmのBi2Sr2Ca1Cu2O
α層を形成した。[Manufacture of oxide superconducting element (Josephson element)] Using a Bi 2 Sr 2 Ca 1 Cu 2 O α target, a high-frequency magnetron sputter in a mixed gas of 7 Pa consisting of 95 mol% of argon and 5 mol% of oxygen , Substrate temperature 700 ℃ 10 × 1
On a 0 × 1 mm SrTiO 3 substrate, a 1.0 μm thick Bi 2 Sr 2 Ca 1 Cu 2 O
An α layer was formed.
次に、Bi2Sr2Y1Cu2Oαターゲットを用いて、上記Bi2S
r2Ca1Cu2Oα層上に、厚さ10ÅのBi2Sr2Y1Cu2Oα層を形
成した。Next, using the Bi 2 Sr 2 Y 1 Cu 2 O α target, the above Bi 2 S
the r 2 Ca 1 Cu 2 O α layer was formed on the Bi 2 Sr 2 Y 1 Cu 2 O α layer having a thickness of 10 Å.
最後に、このBi2Sr2Y1Cu2Oα層上に、前述した条件と
同じ条件で、厚さ1.0μmのBi2Sr2Ca1Cu2Oα層を形成し
て、トンネル接合型の酸化物超電導素子を得た。Finally, a 1.0 μm thick Bi 2 Sr 2 Ca 1 Cu 2 O α layer is formed on the Bi 2 Sr 2 Y 1 Cu 2 O α layer under the same conditions as described above, and a tunnel junction type Was obtained.
このようにして得られた酸化物超電導素子の臨界温度
は77Kで、この温度でトンネル効果により各層を通じて
電流が流れることが確認された。The critical temperature of the oxide superconducting device thus obtained was 77 K, and it was confirmed that current flowed through each layer by the tunnel effect at this temperature.
絶縁層として、Tl2Ba2Y1Cu2Oαターゲットを用いてTl
2Ba2Y1Cu2Oα層を形成し、超電導体としてTl2Ba2Ca1Cu2
Oαターゲットを用いてTl2Ba2Ca1Cu2Oα層を形成した以
外は、上記の方法と同様にして酸化物超電導素子を形成
したところ、臨界温度は100Kで動作が確認された。Tl 2 Ba 2 Y 1 Cu 2 O α target was used as the insulating layer.
2 Ba 2 Y 1 Cu 2 O Form an α layer and use Tl 2 Ba 2 Ca 1 Cu 2 as a superconductor
O alpha except for using a target to form a Tl 2 Ba 2 Ca 1 Cu 2 O α layer was in the same manner as described above to form an oxide superconducting element, the critical temperature operate in 100K was confirmed.
実施例2 Bi2Sr2Ca1Cu2Oαターゲットに代えて、Bi2Sr2Ca2Cu3O
αターゲットを用いてBi2Sr2Ca1Cu2Oα層3、5の代り
に、Bi2Sr2Ca2Cu3Oα層を形成した以外は、実施例1と
同様にして酸化物超電導素子を製造した。Example 2 Bi 2 Sr 2 Ca 2 Cu 3 O Instead of Bi 2 Sr 2 Ca 1 Cu 2 O α target, Bi 2 Sr 2 Ca 2 Cu 3 O
Oxide superconductivity was obtained in the same manner as in Example 1 except that a Bi 2 Sr 2 Ca 2 Cu 3 O α layer was formed instead of the Bi 2 Sr 2 Ca 1 Cu 2 O α layers 3 and 5 using an α target. The device was manufactured.
この硫化物超電導素子の臨界温度は70Kで、この温度
でトンネル効果により各層を通じて電流が流れることが
確認された。The critical temperature of this sulfide superconducting element was 70 K, and it was confirmed that current flowed through each layer by the tunnel effect at this temperature.
比較例1 実施例1におけるBi2Sr2Y1Cu2Oα層4に代えて、同じ
厚さのAl2O3層を形成した以外は、実施例1と同じ構造
の酸化物超電導素子を形成したが、この素子は、77Kの
臨界温度においても動作しなかった。Comparative Example 1 An oxide superconducting device having the same structure as in Example 1 except that an Al 2 O 3 layer having the same thickness was formed instead of the Bi 2 Sr 2 Y 1 Cu 2 O α layer 4 in Example 1 was used. Although formed, the device did not operate at a critical temperature of 77K.
なお、以上の実施例では、絶縁層として、Bi2Sr2Y1Cu
2Oαからなる非導電性酸化物を用いた例について説明し
たが、上記式においてYをNd、Sm、Eu、Gd、Tb、Dy、H
o、Er、Tm、YbまたはLuに代えた酸化物でも同様の結晶
構造を有するので同様の効果を得ることが可能である。In the above embodiment, Bi 2 Sr 2 Y 1 Cu was used as the insulating layer.
Although an example using a non-conductive oxide composed of 2 O α has been described, in the above formula, Y is Nd, Sm, Eu, Gd, Tb, Dy, H
Oxide in place of o, Er, Tm, Yb or Lu also has the same crystal structure, so that the same effect can be obtained.
実施例3 Bi、Sr、Y、Cuを原子比で3:2:1:3となるように原料
のBi2O3、SrCO3、Y2O3、CuOを総量100g秤量・混合し、
アルミナルツボに入れ、1150℃大気中で24H保持した
後、800℃まで100Hかけて除冷し、室温まで炉冷して20m
m×20mm×2mmのBi2Sr2YCu2Oα単結晶を得た。X線回折
の結果、単結晶であり、また(001)ファセットを有す
ることを確認した。Example 3 Bi 2 O 3 , SrCO 3 , Y 2 O 3 , and CuO as raw materials were weighed and mixed in a total amount of 100 g so that Bi, Sr, Y, and Cu were in an atomic ratio of 3: 2: 1: 3,
Put in an alumina crucible, hold at 1150 ° C in the atmosphere for 24H, then cool to 800 ° C over 100H, cool down to room temperature, 20m
A single crystal of Bi 2 Sr 2 YCu 2 O α of m × 20 mm × 2 mm was obtained. As a result of X-ray diffraction, it was confirmed that it was a single crystal and had a (001) facet.
この基板上にRFスパッタ法により、Bi2Sr2CaCu2Oα膜
を基板温度550℃で成膜したところ、基板と方位の揃っ
た酸化物超電導単結晶膜が得られた。また、この膜の断
面をEPMAで分析したところ、基板と膜との反応は測定限
界内であった。第2図にこの膜の電気抵抗率の温度特性
を示す。Tc=84K、△Tc〜1Kと優れた超電導特性が得ら
れた。By RF sputtering on the substrate, was deposited Bi 2 Sr 2 CaCu 2 O α film at a substrate temperature of 550 ° C., the oxide superconductor single crystal film of uniform substrate and orientation were obtained. When the cross section of this film was analyzed by EPMA, the reaction between the substrate and the film was within the measurement limit. FIG. 2 shows the temperature characteristics of the electrical resistivity of this film. Excellent superconducting characteristics of Tc = 84K and ΔTc〜1K were obtained.
比較例2 基板としてMgO単結晶を用いた以外は実施例3と同一
条件下で成膜を行ったところ、C面配向した膜が得られ
たものの配向度70%程度の多結晶膜で膜表面の凹凸が大
きく、膜断面のEPMA分析により、膜内にMgOイオンが検
出された。Comparative Example 2 A film was formed under the same conditions as in Example 3 except that a MgO single crystal was used as a substrate. A film having a C-plane orientation was obtained, but a polycrystalline film having a degree of orientation of about 70% was used. The MgO ions were detected in the film by EPMA analysis of the film cross section.
実施例4 Bi、Sr、Nd、Cuを原子比で4:2:2:5となるように秤量
し、実施例3と同様に単結晶を育成し、10mm×10mm×1m
mのBi2Sr2Nd2Cu3Oα単結晶を得、X線回折の結果、単結
晶であり、(001)ファセットを有することを確認し
た。この基板上にクラスターイオンビーム法によりBi2S
r2Ca2Cu3Oα膜を基板温度450℃で成膜したところ、基板
と方位の揃った酸化物超電導単結晶膜が得られた。Example 4 Bi, Sr, Nd, and Cu were weighed so that the atomic ratio was 4: 2: 2: 5, and a single crystal was grown in the same manner as in Example 3, and 10 mm × 10 mm × 1 m
m 2 Bi 2 Sr 2 Nd 2 Cu 3 O α single crystal was obtained, and as a result of X-ray diffraction, it was confirmed that it was a single crystal and had a (001) facet. Bi 2 S was deposited on this substrate by the cluster ion beam method.
When an r 2 Ca 2 Cu 3 O α film was formed at a substrate temperature of 450 ° C., an oxide superconducting single crystal film having the same orientation as the substrate was obtained.
実施例5 出発原料としてBi2O3、PbO、SrCO3、Y2O3、CuOの各粉
末を用意し、これらを陽イオンの原子比がBi:Pb:Sr:Y:C
u=1:1:2:1:2となるように所定量秤量、さらにこれにフ
ァックス分としてのBi2O3とCuOとをBiとCuの原子比がそ
れぞれ1づつとなるように加え、これを充分に混合し
た。Example 5 Powders of Bi 2 O 3 , PbO, SrCO 3 , Y 2 O 3 , and CuO were prepared as starting materials, and the atomic ratio of the cations was Bi: Pb: Sr: Y: C.
A predetermined amount is weighed so that u = 1: 1: 2: 1: 2, and further, Bi 2 O 3 and CuO as a fax component are added so that the atomic ratio of Bi and Cu becomes one, respectively. This was mixed well.
次に、この混合粉をアルミナルツボに投入し、空気中
で1150℃まで加熱し、この温度を24時間保持して均一に
溶融させた後、800℃まで100時間かけて除冷し、次で室
温まで炉冷した。Next, the mixed powder was put into an alumina crucible, heated to 1150 ° C. in the air, kept at this temperature for 24 hours to uniformly melt, and then cooled to 800 ° C. over 100 hours, and then cooled. The furnace was cooled to room temperature.
得られた冷却固化物中には10mm X 20mm X 2mmと大型
の単結晶が析出しており、この単結晶体のX線解析を行
ったところ、BiPbSr2Y Cu2O8+δ(δは過剰酸素)の
組成を有し、単結晶板面に対したc軸配向して単結晶で
あることを確認した。また、比抵抗は−100℃で104Ω・
cmであり、電気絶縁物として機能することを確認した。A large single crystal having a size of 10 mm × 20 mm × 2 mm was precipitated in the obtained cooled solidified product. An X-ray analysis of this single crystal showed that BiPbSr 2 YCu 2 O 8 + δ (δ is excess oxygen) ), And was confirmed to be a single crystal with c-axis orientation with respect to the single crystal plate surface. The specific resistance is 104Ω at -100 ° C.
cm, and confirmed to function as an electrical insulator.
次に、上記BiPbSr2Y Cu2O8+δ単結晶基板上にBi
2O3、PbO、SrCO3、CaCO3およびCuOをスパッタターゲッ
トとして用い、95mol%のアルゴンと5mol%の酸素から
なる7Paの混合気体中で、高周波マグネトロンスパッタ
による多元スパッタによって、Bi系酸化物超電導体薄膜
を膜厚200Åで着膜させた。なお、各ターゲットに対す
る投入電力比は、形成される薄膜の組成がBi:Sr:Ca:Cu
=2:2:2:3となるように調整した。Next, the BiPbSr 2 Y Cu 2 O 8 + δ Bi on a single crystal substrate
Bi-based oxide superconducting by multi-source sputtering by high-frequency magnetron sputtering in a mixed gas of 95 mol% of argon and 5 mol% of oxygen, using 2 O 3 , PbO, SrCO 3 , CaCO 3 and CuO as a sputtering target. A body thin film was deposited to a thickness of 200 °. Note that the input power ratio for each target is such that the composition of the formed thin film is Bi: Sr: Ca: Cu
= 2: 2: 2: 3.
得られたBi系酸化物超電導体薄膜に対してX線回折を
行ったところ、絶縁性単結晶基板と方位のそろった高臨
界温度相のエピタキシャル成長膜であることを確認し
た。X-ray diffraction was performed on the obtained Bi-based oxide superconductor thin film, and it was confirmed that the Bi-based oxide superconductor thin film was an epitaxially grown film having a high critical temperature phase aligned with an insulating single crystal substrate.
これは、この実施例の絶縁性単結晶基板はBi系酸化物
超電導体と格子定数が近似しており、界面における格子
不整合が極力低減されるため、Bi系酸化物超電導体薄膜
を良好に形成することが可能になるためである。This is because the insulating single crystal substrate of this example has a lattice constant similar to that of the Bi-based oxide superconductor, and lattice mismatch at the interface is reduced as much as possible. This is because it can be formed.
また、Bi系酸化物超電導体の高臨界温度相が形成しず
らい理由は、結晶内部の変調構造やその原因である結晶
の内部応力に起因するものと考えられる。ところで、こ
の実施例の絶縁性単結晶基板は、Bi系酸化物超電導体と
格子定数が近似しているとともに、Pbの置換によって変
調構造もほぼ消失したものである。このために、この実
施例の絶縁性単結晶基板上に形成されたBi系酸化物超電
導体薄膜も消失あるいは緩和され、高臨界温度相の単一
相が得られるものと推定される。Further, it is considered that the reason why the high critical temperature phase of the Bi-based oxide superconductor is difficult to form is due to the modulated structure inside the crystal and the internal stress of the crystal which is the cause thereof. By the way, the insulating single crystal substrate of this example has a lattice constant similar to that of the Bi-based oxide superconductor, and the modulation structure has almost disappeared by the substitution of Pb. For this reason, it is presumed that the Bi-based oxide superconductor thin film formed on the insulating single crystal substrate of this example also disappears or is relaxed, and a single phase having a high critical temperature phase is obtained.
さらに、この実施例の絶縁性単結晶基板上に形成され
たBi系酸化物超電導体薄膜上に、Bi2O3、PbO、SrCO3、Y
2O3およびCuOをスパッタターゲットとして用い、高周波
マグネトロンスパッタによる多元スパッタによって、Bi
PbSr2Y Cu2O8+δ薄膜を膜厚50Åで形成し、さらに上
に上記酸化物超電導体薄膜と同一条件でBi系酸化物超電
導体薄膜を膜厚200Åで形成し、ジョセフソン素子を作
成した。Further, Bi 2 O 3 , PbO, SrCO 3 , and Y were formed on the Bi-based oxide superconductor thin film formed on the insulating single crystal substrate of this example.
Bi-sputtering by high frequency magnetron sputtering using 2 O 3 and CuO as sputtering targets
A PbSr 2 Y Cu 2 O 8 + δ thin film was formed with a thickness of 50 °, and a Bi-based oxide superconductor thin film was further formed thereon with a thickness of 200 ° under the same conditions as the above oxide superconductor thin film to produce a Josephson device. .
上層のBi系酸化物超電導体薄膜も、下相のBi系酸化物
超電導体薄膜と同様に、高臨界温度相によって構成され
た良好な酸化物超電導体薄膜であり、Bi系酸化物超電導
体層と絶縁相の界面における反応も認められなかった。
また、このジョセフソン素子は110Kで超電導特性を示
し、この温度で良好なジョセフソン効果が得られること
を確認した。Like the lower Bi-based oxide superconductor thin film, the upper Bi-based oxide superconductor thin film is also a good oxide superconductor thin film composed of a high critical temperature phase. No reaction was observed at the interface between the metal and the insulating phase.
In addition, this Josephson device exhibited superconducting characteristics at 110 K, and it was confirmed that a good Josephson effect was obtained at this temperature.
比較例3 SrTiO3Oを基板として用いて、この上にBi2Sr2Ca2Cu2C
u3O10+δ超電導体を200Å、絶縁層してMgOを50Å、さ
らにBi2Sr2Ca2Cu3O10+δ超電導体を200Å積層してジョ
セフソン素子を作製した。Comparative Example 3 Using SrTiO 3 O as a substrate, Bi 2 Sr 2 Ca 2 Cu 2 C
200Å and u 3 O 10 + δ superconductor, an insulating layer to 50Å and MgO, to produce a Josephson device further 200Å laminated Bi 2 Sr 2 Ca 2 Cu 3 O 10 + δ superconductor.
しかしながら、このままの状態では超電導特性を示さ
なかった。そこで、結晶性を向上させるため600℃で熱
処理を行い、超電導特性を評価したところ、転移温度60
Kで超電導状態を示したものの、良好なジョセフソン特
性は得られなかった。However, in this state, no superconductivity was exhibited. Therefore, a heat treatment was performed at 600 ° C. to improve the crystallinity, and the superconductivity was evaluated.
Although a superconducting state was shown at K, good Josephson characteristics could not be obtained.
実施例6 実施例5の記載された同様の方法により、PbによるBi
の置換量を変化させてBi2-wPbwSr2Y Cu2O8+δの単結
晶を作成した。Example 6 Bi by Pb was prepared in a similar manner as described in Example 5.
Created a single crystal of Bi 2-w Pb w Sr 2 Y Cu 2 O 8 + δ by changing the amount of substitution.
本発明のBi2-wPbwSr2Y Cu2O8+δ結晶と超電導体のB
i2Sr2CaCu2O8+δの格子定数、およびBi2−wPbwSr2Y
Cu2O8+δ結晶の変調構造を第3図に示す。Bi 2-w Pb w Sr 2 Y Cu 2 O 8 + δ crystal of the present invention and superconductor B
Lattice constant of i 2 Sr 2 CaCu 2 O 8 + δ and Bi 2-w Pb w Sr 2 Y
FIG. 3 shows the modulation structure of the Cu 2 O 8 + δ crystal.
図中で、横軸はWを示する。すなわち、Wが大きくな
るほど、BiはPbに置換される割合が大きくなる。左の上
の縦軸はc軸の格子定数を示し、右の下の縦軸はa、b
軸の格子定数を示す。右の上の縦軸は変調構造を示す。In the figure, the horizontal axis indicates W. That is, as W increases, the proportion of Bi replaced with Pb increases. The upper left ordinate indicates the lattice constant of the c axis, and the lower right ordinate indicates a, b
Shows the lattice constant of the axis. The vertical axis on the right shows the modulation structure.
○はBi2-wPbwSr2Y Cu2O8+δ結晶のa軸の格子定数
を、●はb軸の格子定数を、 はc軸の格子定数を示す。○ indicates the lattice constant of the a-axis of Bi 2-w Pb w Sr 2 Y Cu 2 O 8 + δ crystal, ● indicates the lattice constant of the b-axis, Represents the lattice constant of the c-axis.
◎はBi2Sr2CaCu2O8+δのa軸およびb軸の格子定数
を、□はc軸の格子定数を示す。◎ indicates the lattice constant of Bi 2 Sr 2 CaCu 2 O 8 + δ on the a-axis and b-axis, and □ indicates the lattice constant of c-axis.
△はBi2-wPbwSr2Y Cu2O8+δ結晶の変調構造を示
す。Δ indicates the modulation structure of Bi 2-w Pb w Sr 2 Y Cu 2 O 8 + δ crystal.
Bi2-wPbwSr2Y Cu2O8+δ結晶において、b軸の格子
定数は、Biの約60%をPbで置換すると、Bi2Sr2CaCu2O
8+δに最も近ずき、c軸の格子定数は、BiがPbに置換
される割合が大きくなると、Bi2Sr2CaCu2O8+δに近ず
くことがわかる。In Bi 2-w Pb w Sr 2 Y Cu 2 O 8 + δ crystal, the lattice constant of the b-axis is Bi 2 Sr 2 CaCu 2 O when about 60% of Bi is replaced by Pb.
It can be seen that the lattice constant of the c-axis approaches Bi 2 Sr 2 CaCu 2 O 8 + δ when the proportion of Bi substituted by Pb increases.
さらに、変調構造は、BiがPbに置換される割合が大き
くなると、消失することがわかる。Further, it can be seen that the modulation structure disappears when the ratio of replacing Bi with Pb increases.
実施例7〜16 第1表および第2表に示す組成でフラックス法により
絶縁性単結晶を作製した。Examples 7 to 16 Insulating single crystals were prepared by the flux method using the compositions shown in Tables 1 and 2.
[発明の効果] 以上説明したように本発明の絶縁性組成物は酸化物超
電導体と結晶構造が同一または類似のため、酸化物超電
導体の結晶面との整合性の良好な絶縁性組成物を提供す
ることができる。さらに、本発明の絶縁性組成物のBiの
一部をPbで置き換えることにより、変調構造の緩和また
は消失した絶縁性組成物を提供することができる。 [Effects of the Invention] As described above, since the insulating composition of the present invention has the same or similar crystal structure as the oxide superconductor, the insulating composition has good matching with the crystal plane of the oxide superconductor. Can be provided. Further, by replacing a part of Bi in the insulating composition of the present invention with Pb, it is possible to provide an insulating composition in which the modulation structure is relaxed or eliminated.
【図面の簡単な説明】 第1図は本発明の絶縁性組成物が絶縁層である酸化物超
電導素子の横断面図、第2図は本発明による短結晶基板
上に成膜した酸化物超電導薄膜単結晶の電気抵抗率の温
度特性を示す図、第3図は、本発明のBiの一部がPbで置
換された絶縁組成物の特性を示す図である。 1……酸化物超電導素子、2……基板、3、5……Bi2S
r2Ca1Cu2Oα層、4……Bi2Sr2Y1Cu2Oα層BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of an oxide superconducting element in which the insulating composition of the present invention is an insulating layer, and FIG. 2 is an oxide superconducting film formed on a short crystal substrate according to the present invention. FIG. 3 is a graph showing the temperature characteristics of the electrical resistivity of the thin film single crystal, and FIG. 3 is a graph showing the characteristics of the insulating composition of the present invention in which Bi is partially substituted with Pb. 1 ... oxide superconducting element, 2 ... substrate, 3, 5 ... Bi 2 S
r 2 Ca 1 Cu 2 O α layer, 4 ... Bi 2 Sr 2 Y 1 Cu 2 O α layer
───────────────────────────────────────────────────── フロントページの続き (31)優先権主張番号 特願平1−77607 (32)優先日 平1(1989)3月29日 (33)優先権主張国 日本(JP) (72)発明者 安藤 健 神奈川県川崎市幸区小向東芝町1 株式 会社東芝総合研究所内 (72)発明者 丹生 ひろみ 神奈川県川崎市幸区小向東芝町1 株式 会社東芝総合研究所内 (72)発明者 山下 知久 神奈川県川崎市幸区小向東芝町1 株式 会社東芝総合研究所内 (56)参考文献 特開 昭63−32974(JP,A) 特開 昭63−307197(JP,A) Japanese Journal of Applied Physics Part2 vol27.No5 p. L790−791 Japanese Journal of Applied Physics Part2 vol27.No2 p. L209−210 Physical Review L etters vol61,No6,750 −753 Japanese Journal of Applied Physics Part2 vol27.No10 p. L1852−1855 (58)調査した分野(Int.Cl.6,DB名) C01G 1/00 - 23/08 C01G 29/00 C30B 29/22 CAS on−line──────────────────────────────────────────────────続 き Continued on the front page (31) Priority claim number Japanese Patent Application No. 1-77607 (32) Priority date Hei 1 (1989) March 29 (33) Priority claim country Japan (JP) (72) Inventor Takeshi Ando 1 Toshiba R & D Co., Ltd., Koyuki-ku, Kawasaki-shi, Kanagawa Prefecture (72) Inside the Toshiba Research Institute, Inc. Hiromi Nibu 1 Toshiba Komukai-Toshiba-cho, Kochi-ku, Kawasaki-shi, Kanagawa Prefecture Within Toshiba Research Institute, Inc. (72) Tomohisa Yamashita, Inventor 1 Toshiba Research Institute, Komukai, Kawasaki-shi, Kanagawa Prefecture (56) References JP-A-63-32974 (JP, A) JP-A-63-307197 (JP, A) Japane Journal of Applied Physics Part 2 vol27. No5 p.L790-791 Japanese Journal of Applied Physics Part2 vol27. No2 p. L209-210 Physical Review Letters vol 61, No6,750-753 Japanese Journal of Applied Physics Part2 vol 27. No10 p. L1852-1855 (58) Fields investigated (Int. Cl. 6 , DB name) C01G 1/00-23/08 C01G 29/00 C30B 29/22 CAS on-line
Claims (4)
Cu、Oからなる酸化物超電導体組成物のCaがRE(但し、
REは、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Luお
よびYから選ばれた元素。)で置換され、かつBi、Sr、
RE、Cuまたは、Tl、Ba、RE、Cuの原子比が2:X:Y:Zであ
ることを特徴とする絶縁性組成物。 但し、1.5≦X≦2.5 0.5≦Y≦1.5 1.8≦Z≦2.5(1) Bi, Sr, Ca, Cu, O or Tl, Ba, Ca,
Ca of the oxide superconductor composition comprising Cu and O is RE (however,
RE is an element selected from Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y. ) And Bi, Sr,
An insulating composition characterized in that the atomic ratio of RE, Cu or Tl, Ba, RE, Cu is 2: X: Y: Z. However, 1.5 ≦ X ≦ 2.5 0.5 ≦ Y ≦ 1.5 1.8 ≦ Z ≦ 2.5
物である絶縁性組成物を、 但し、1.5≦X≦2.5 0.5≦Y≦1.5 1.8≦Z≦2.5 フラックス法で育成する際のフラックスとしてBi2O3とC
uOを同時に含むフラックスを用いることを特徴とする絶
縁性組成物の育成方法。2. An insulating composition which is an oxide having an atomic ratio of Bi, Sr, RE and Cu of 2: X: Y: Z, provided that 1.5 ≦ X ≦ 2.5 0.5 ≦ Y ≦ 1.5 1.8 ≦ Z ≦ 2.5 Bi 2 O 3 and C as flux when growing by the flux method
A method for growing an insulating composition, comprising using a flux containing uO at the same time.
物である絶縁性組成物を、 但し、1.5≦X≦2.5 0.5≦Y≦1.5 1.8≦Z≦2.5 フラックス法で育成する際の各原料陽イオンの組成が、
モル比%(β、γ、ε)で、 βBi2O3+γ{(Sr、RE)O}+εCuO 但し、5≦β≦25 20≦γ≦60 10≦ε≦60 2β+γ+ε=100 の関係を満足することを特徴とする絶縁性組成物の育成
方法。3. An insulating composition comprising an oxide having an atomic ratio of Bi, Sr, RE and Cu of 2: X: Y: Z, provided that 1.5 ≦ X ≦ 2.5 0.5 ≦ Y ≦ 1.5 1.8 ≦ Z ≦ 2.5 The composition of each raw material cation when growing by the flux method is
In the molar ratio% (β, γ, ε), βBi 2 O 3 + γ {(Sr, RE) O} + εCuO, where 5 ≦ β ≦ 25 20 ≦ γ ≦ 60 10 ≦ ε ≦ 60 2β + γ + ε = 100 is satisfied. A method for growing an insulating composition, comprising:
組成物を絶縁層として形成したことを特徴とする超電導
素子。4. A superconducting element comprising the insulating composition according to claim 1 formed on an oxide superconductor as an insulating layer.
Applications Claiming Priority (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP63-86730 | 1988-04-08 | ||
JP8673088 | 1988-04-08 | ||
JP10028188 | 1988-04-25 | ||
JP63-100281 | 1988-04-25 | ||
JP7495989 | 1989-03-29 | ||
JP1-77607 | 1989-03-29 | ||
JP7760789 | 1989-03-29 | ||
JP1-74959 | 1989-03-29 |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0350122A JPH0350122A (en) | 1991-03-04 |
JP2975608B2 true JP2975608B2 (en) | 1999-11-10 |
Family
ID=27465761
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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JP1088503A Expired - Lifetime JP2975608B2 (en) | 1988-04-08 | 1989-04-07 | Insulating composition |
Country Status (1)
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JP (1) | JP2975608B2 (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2740260B2 (en) * | 1988-05-11 | 1998-04-15 | キヤノン株式会社 | Josephson element |
JPH0465320A (en) * | 1990-06-29 | 1992-03-02 | Matsushita Electric Works Ltd | Superconducting thin film and its production |
JPH04130093A (en) * | 1990-09-21 | 1992-05-01 | Nec Corp | Production of oxide superconductor single crystal and method for controlling superconductivity transition temperature |
US5629267A (en) * | 1992-06-16 | 1997-05-13 | Kabushiki Kaisha Toshiba | Superconducting element having an intermediate layer with multiple fluorite blocks |
JPH0715049A (en) * | 1993-06-23 | 1995-01-17 | Nec Corp | Superconducting multilayered thin film |
-
1989
- 1989-04-07 JP JP1088503A patent/JP2975608B2/en not_active Expired - Lifetime
Non-Patent Citations (4)
Title |
---|
Japanese Journal of Applied Physics Part2 vol27.No10 p.L1852−1855 |
Japanese Journal of Applied Physics Part2 vol27.No2 p.L209−210 |
Japanese Journal of Applied Physics Part2 vol27.No5 p.L790−791 |
Physical Review Letters vol61,No6,750−753 |
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JPH0350122A (en) | 1991-03-04 |
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