JP2840475B2 - Method for producing oxide superconducting thin film - Google Patents
Method for producing oxide superconducting thin filmInfo
- Publication number
- JP2840475B2 JP2840475B2 JP3074677A JP7467791A JP2840475B2 JP 2840475 B2 JP2840475 B2 JP 2840475B2 JP 3074677 A JP3074677 A JP 3074677A JP 7467791 A JP7467791 A JP 7467791A JP 2840475 B2 JP2840475 B2 JP 2840475B2
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- heat treatment
- mixed powder
- cuo
- oxide superconducting
- 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
Links
- 239000010409 thin film Substances 0.000 title claims description 40
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 238000010438 heat treatment Methods 0.000 claims description 29
- 239000011812 mixed powder Substances 0.000 claims description 22
- 239000002887 superconductor Substances 0.000 claims description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 14
- 239000001301 oxygen Substances 0.000 claims description 14
- 229910052760 oxygen Inorganic materials 0.000 claims description 14
- 229910002480 Cu-O Inorganic materials 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 9
- 229910052791 calcium Inorganic materials 0.000 claims description 7
- 229910052802 copper Inorganic materials 0.000 claims description 6
- 229910052788 barium Inorganic materials 0.000 claims description 5
- 238000000137 annealing Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 5
- 150000001875 compounds Chemical class 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000010408 film Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 238000000879 optical micrograph Methods 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 241000238366 Cephalopoda Species 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 230000005668 Josephson effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 239000001307 helium Substances 0.000 description 1
- 229910052734 helium Inorganic materials 0.000 description 1
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 1
- 238000005339 levitation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、高い超伝導転移温度
（Ｔｃ）を持つ酸化物超伝導薄膜の製造方法に関するも
のである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an oxide superconducting thin film having a high superconducting transition temperature (Tc).
【０００２】[0002]
【従来の技術】超伝導材料は、（１）電気抵抗がゼロで
ある、（２）完全反磁性である、（３）ジョセフソン効
果がある、といった、他の材料にない特性を持ってお
り、既に超伝導マグネットや、ＳＱＵＩＤ等に利用され
ている。また今後も、電力輸送、発電機、核融合プラズ
マ閉じ込め、磁気浮上列車、磁気シールド、高速コンピ
ュータ等の幅広い応用が期待されている。その材料とし
ては、従来、Ｎｂ3 Ｇｅ等の金属系の超伝導体が用いら
れていた。ところが、金属系超伝導体では、Ｔｃは最も
高いものでも２３Ｋ程度であり、実使用時には高価な液
体ヘリウムと大がかりな断熱装置を使って冷却しなけれ
ばならず、工業上大きな問題であった。このため、より
高温で超伝導体となる材料の探索が行われていた。2. Description of the Related Art Superconducting materials have characteristics that are not found in other materials, such as (1) zero electrical resistance, (2) perfect diamagnetism, and (3) a Josephson effect. Are already used for superconducting magnets, SQUIDs and the like. In the future, a wide range of applications such as power transport, generators, fusion plasma confinement, magnetic levitation trains, magnetic shields, and high-speed computers are expected. Conventionally, a metal-based superconductor such as Nb 3 Ge has been used as the material. However, in the case of a metal-based superconductor, the highest Tc is about 23K even at the highest, and it has to be cooled using expensive liquid helium and a large-scale heat insulating device at the time of actual use, which is a serious industrial problem. For this reason, a search for a material that becomes a superconductor at higher temperatures has been conducted.
【０００３】1986年にベドノルツ(Bednorz) とミューラ
ー(Muller)により約４０Ｋという高いＴｃを有する、酸
化物系超伝導材料（Ｌａ1-Z ＳｒZ ）2 ＣｕＯx が見い
だされ、それ以後ＹＢａ2 Ｃｕ3 Ｏx 、Ｂｉ−Ｓｒ−Ｃ
ａ−Ｃｕ−Ｏ、Ｔｌ−Ｂａ−Ｃａ−Ｃｕ−Ｏなどで、相
次いでより高い温度での超伝導転移が報告されている。
Ｔｃが高いほど冷却が容易となり、また同じ温度で使用
した場合の臨界電流密度や臨界磁場も大きくなる事が予
想され、応用範囲も広がるものと期待される。Ｔｌ−Ｂ
ａ−Ｃａ−Ｃｕ−Ｏ系酸化物超伝導体には、それぞれの
モル比が、1:2:0:1 、1:2:1:2 、1:2:2:3 、 1:2:3:4、
1:2:4:5、2:2:0:1 、 2:2:1:2、2:2:2:3 、 2:2:3:4の
９種類が報告されている。現在、最も高いＴｃとしては
Ｔｌ2 Ｂａ2 Ｃａ2 Ｃｕ3 Ｏy （"2223"相と略記する）
の 125Ｋ（電気抵抗ゼロ）が報告されている。In 1986, Bednorz and Muller discovered an oxide-based superconducting material (La 1 -ZSr Z ) 2 CuO x having a high Tc of about 40 K, and since then YBa 2 Cu 3 O x , Bi-Sr-C
Superconducting transitions at successively higher temperatures have been reported for a-Cu-O, Tl-Ba-Ca-Cu-O, and the like.
It is expected that the higher the Tc, the easier the cooling becomes, and that the critical current density and the critical magnetic field when used at the same temperature are also increased, which is expected to broaden the application range. Tl-B
In the a-Ca-Cu-O-based oxide superconductor, the respective molar ratios are 1: 2: 0: 1, 1: 2: 1: 2, 1: 2: 2: 3, 1: 2: 3: 4,
Nine types of 1: 2: 4: 5, 2: 2: 0: 1, 2: 2: 1: 2, 2: 2: 2: 3, and 2: 2: 3: 4 have been reported. Currently, (abbreviated as "2223" phase) Tl 2 Ba 2 Ca 2 Cu 3 O y as the highest Tc
Of 125K (zero electrical resistance) has been reported.
【０００４】Ｔｌは人体に有害なため、Ｔｌ系の酸化物
を合成する際にはＴｌに触れる工程をできるだけ省き、
またなるべく実験系をＴｌで汚染しないような方法が望
ましい。そこで、あらかじめＴｌ以外の元素から成る薄
膜を作製しておいて、後から熱処理によってＴｌを気相
から導入するＴｌ−Ｂａ−Ｃａ−Ｃｕ−Ｏ薄膜の製造方
法が提案されている。[0004] Since Tl is harmful to the human body, when synthesizing a Tl-based oxide, the step of touching Tl is omitted as much as possible.
It is also desirable to use a method that does not contaminate the experimental system with Tl. Therefore, a method of manufacturing a Tl-Ba-Ca-Cu-O thin film in which a thin film made of an element other than Tl is prepared in advance, and Tl is introduced from a gas phase by heat treatment later has been proposed.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、前記従
来例の、はじめにＴｌ以外の元素から成る薄膜を作製し
た後にＴｌ2 Ｏ3 と共に熱処理しＴｌを気相から導入す
る方法では、Ｔｌ−Ｂａ−Ｃａ−Ｃｕ−Ｏ系酸化物超伝
導体には上記の９種類の多形が存在するため単相化する
のが非常に難しいという課題がある。また、Ｔｌを含有
する化合物と共に熱処理しＴｌを導入する方法では、あ
らかじめＴｌ含有化合物を合成しておく必要があり、Ｔ
ｌを扱う工程が増えてしまう。例えばセラミックスのＴ
ｌ含有化合物を用いるならば、秤量、混合、（仮焼、粉
砕）、造粒、成形、焼成、といった工程が必要となり、
Ｔｌに触れる工程が少なく実験系を汚染しないというＴ
ｌを気相から導入する方法の利点が損なわれるという課
題がある。However, in the method of the prior art, a thin film made of an element other than Tl is first prepared and then heat-treated with Tl 2 O 3 to introduce Tl from the gas phase. The -Cu-O-based oxide superconductor has a problem that it is very difficult to form a single phase due to the presence of the above nine types of polymorphs. In the method of introducing Tl by heat treatment with a compound containing Tl, it is necessary to synthesize a Tl-containing compound in advance.
The number of steps for handling 1 increases. For example, ceramic T
If an l-containing compound is used, steps such as weighing, mixing, (calcination, pulverization), granulation, molding, and firing are required,
T that there are few steps to touch Tl and do not contaminate the experimental system
There is a problem that the advantage of the method of introducing l from the gas phase is lost.
【０００６】本発明は、前記従来技術の課題を解決する
ため、Ｔｌ−Ｂａ−Ｃａ−Ｃｕ−Ｏ系酸化物超伝導体の
単相化を容易にし、Ｔｌに触れる工程を少なくして環境
を汚染させず、再現性よくＴｌ−Ｂａ−Ｃａ−Ｃｕ−Ｏ
系酸化物超伝導体をえることができる製造方法を提供す
ることを目的とする。In order to solve the above-mentioned problems of the prior art, the present invention facilitates the formation of a single-phase Tl-Ba-Ca-Cu-O-based oxide superconductor, reduces the number of steps of contact with Tl, and reduces the environment. Tl-Ba-Ca-Cu-O with good reproducibility without contamination
It is an object of the present invention to provide a manufacturing method capable of obtaining a system oxide superconductor.
【０００７】[0007]
【課題を解決するための手段】前記目的を達成するた
め、本発明の酸化物超伝導薄膜の製造方法は、Ｔｌ−Ｂ
ａ−Ｃａ−Ｃｕ−Ｏ系酸化物超伝導体薄膜の製造方法に
おいて、Ｂａ、Ｃａ、Ｃｕおよび酸素を含む薄膜を、Ｔ
ｌ2 Ｏ3 、ＢａＣｕＯ2 、Ｃａ2 ＣｕＯ3 、ＣｕＯから
なる混合粉末と同時に熱処理することを特徴とする。In order to achieve the above object, a method for producing a superconducting oxide thin film according to the present invention comprises the steps of:
In the method for producing an a-Ca-Cu-O-based oxide superconductor thin film, the thin film containing Ba, Ca, Cu and oxygen is
The heat treatment is performed simultaneously with the mixed powder of l 2 O 3 , BaCuO 2 , Ca 2 CuO 3 and CuO.
【０００８】前記構成においては、混合粉末の（Ｔｌ＋
Ｂａ＋Ｃａ＋Ｃｕ）に対する（Ｃａ＋Ｃｕ）の割合が、
５５〜８５モル％であることが好ましい。[0008] In the above structure, (Tl +
The ratio of (Ca + Cu) to (Ba + Ca + Cu)
It is preferably 55 to 85 mol%.
【０００９】また前記構成においては、熱処理が酸素雰
囲気中で二段階の熱処理であることが好ましい。とくに
好ましくは、Ｂａ、Ｃａ、Ｃｕおよび酸素を含む薄膜
を、Ｔｌ2 Ｏ3 、ＢａＣｕＯ2 、Ｃａ2 ＣｕＯ3 、Ｃｕ
Ｏからなる混合粉末と同時に熱処理する際、混合粉末の
Ｔｌ：Ｂａ：Ｃａ：Ｃｕの比を１：１：３：３とし、酸
素雰囲気中で少なくとも９００℃および９３０℃におけ
る二段階の熱処理を行なうことである。In the above structure, the heat treatment is preferably a two-stage heat treatment in an oxygen atmosphere. Particularly preferably, a thin film containing Ba, Ca, Cu and oxygen is formed of Tl 2 O 3 , BaCuO 2 , Ca 2 CuO 3 , Cu
When heat-treating simultaneously with the mixed powder of O, the Tl: Ba: Ca: Cu ratio of the mixed powder is set to 1: 1: 3: 3, and two-stage heat treatment is performed at least at 900 ° C. and 930 ° C. in an oxygen atmosphere. That is.
【００１０】[0010]
【作用】前記した本発明の構成によれば、Ｂａ、Ｃａ、
Ｃｕおよび酸素を含む薄膜を、Ｔｌ2 Ｏ3 、ＢａＣｕＯ
2 、Ｃａ2ＣｕＯ3 、ＣｕＯからなる混合粉末と同時に
熱処理することにより、Ｔｌに触れる工程をなるべく増
やさずに、再現性よくＴｌ−Ｂａ−Ｃａ−Ｃｕ−Ｏ系酸
化物超伝導体薄膜が製造できる。According to the structure of the present invention, Ba, Ca,
A thin film containing Cu and oxygen is formed of Tl 2 O 3 , BaCuO
2. By performing the heat treatment simultaneously with the mixed powder composed of Ca 2 CuO 3 and CuO, a Tl-Ba-Ca-Cu-O-based oxide superconductor thin film can be produced with good reproducibility without increasing the number of steps in contact with Tl as much as possible. it can.
【００１１】次に、混合粉末の（Ｔｌ＋Ｂａ＋Ｃａ＋Ｃ
ｕ）に対する（Ｃａ＋Ｃｕ）の割合が、５５〜８５モル
％であるという本発明の好ましい構成によれば、より優
れた特性の酸化物超伝導体薄膜が製造できる。Next, the mixed powder (Tl + Ba + Ca + C)
According to the preferred configuration of the present invention in which the ratio of (Ca + Cu) to u) is 55 to 85 mol%, an oxide superconductor thin film having more excellent characteristics can be manufactured.
【００１２】また、熱処理が酸素雰囲気中で二段階の熱
処理であるという本発明の好ましい構成によれば、より
優れた特性の酸化物超伝導体薄膜が製造できる。さら
に、Ｂａ、Ｃａ、Ｃｕおよび酸素を含む薄膜を、Ｔｌ2
Ｏ3、ＢａＣｕＯ2 、Ｃａ2 ＣｕＯ3 、ＣｕＯからなる
混合粉末と同時に熱処理する際、混合粉末のＴｌ：Ｂ
ａ：Ｃａ：Ｃｕの比を１：１：３：３とし、酸素雰囲気
中で少なくとも９００℃および９３０℃における二段階
の熱処理を行なうというとくに好ましい方法によれば、
Ｔｌ：Ｂａ：Ｃａ：Ｃｕが１：１：３：３でＴｌ
2 Ｏ3 、ＢａＣｕＯ2 、Ｃａ2 ＣｕＯ3 、ＣｕＯから成
る混合粉末をＴｌ源として用い、酸素雰囲気中で９００
℃および９３０℃における二段階の熱処理を行なうこと
は、ＴｌをＢａ−Ｃａ−Ｃｕ−Ｏ薄膜に供給すると同時
に自らはＴｌ2 Ｂａ2 Ｃａ2 Ｃｕ3 Ｏy となり、ついに
はＴｌ2 Ｂａ2 Ｃａ2 Ｃｕ3 Ｏy のＴｌの平衡蒸気圧で
薄膜をアニールすることになる。この方法により再現性
よく均質なＴｌ2 Ｂａ2 Ｃａ2 Ｃｕ3 Ｏy 薄膜が製造で
きる。According to the preferred configuration of the present invention in which the heat treatment is a two-step heat treatment in an oxygen atmosphere, an oxide superconductor thin film having more excellent characteristics can be manufactured. Further, a thin film containing Ba, Ca, Cu, and oxygen is deposited on Tl 2
When heat-treating simultaneously with the mixed powder composed of O 3 , BaCuO 2 , Ca 2 CuO 3 , and CuO, the mixed powder Tl: B
According to a particularly preferred method in which the ratio of a: Ca: Cu is 1: 1: 3: 3 and a two-stage heat treatment at least at 900 ° C. and 930 ° C. is carried out in an oxygen atmosphere,
Tl: Ba: Ca: Cu is 1: 1: 3: 3 and Tl
A mixed powder composed of 2 O 3 , BaCuO 2 , Ca 2 CuO 3 , and CuO is used as a Tl source, and the mixed powder is 900
° C. and performing a heat treatment of two stages at 930 ° C. is itself simultaneously supplying Tl to Ba-Ca-Cu-O thin film Tl 2 Ba 2 Ca 2 Cu 3 O y , and the finally Tl 2 Ba 2 Ca 2 thereby annealing the thin film at equilibrium vapor pressure of Tl of Cu 3 O y. By this method, a uniform Tl 2 Ba 2 Ca 2 Cu 3 O y thin film can be produced with good reproducibility.
【００１３】[0013]
【実施例】以下一実施例を用いて本発明をさらに具体的
に説明する。The present invention will be described more specifically with reference to the following examples.
【００１４】まず、Ｃａ−Ｃａ−Ｃｕ−Ｏ薄膜のスパッ
タ条件を表１に示す。First, Table 1 shows the sputtering conditions for the Ca—Ca—Cu—O thin film.
【００１５】[0015]
【表１】 この条件でＢａ：Ｃａ：Ｃｕ比が 1:2:2の非晶質薄膜が
得られた。[Table 1] Under these conditions, an amorphous thin film having a Ba: Ca: Cu ratio of 1: 2: 2 was obtained.
【００１６】Ｔｌを導入するためのアニール処理は、図
１に示す管状電気炉で行った。試料および混合粉末が幾
重にも蓋をかぶされているが、これはＴｌの急激な蒸発
を防ぐためである。また、これらの機密性は悪く酸素ガ
スは試料や混合粉末に到達していると考えられる。The annealing treatment for introducing Tl was performed in a tubular electric furnace shown in FIG. The sample and the mixed powder are covered several times in order to prevent rapid evaporation of Tl. In addition, it is considered that the confidentiality is poor and the oxygen gas has reached the sample and the mixed powder.
【００１７】図１に示すように、前記スパッタで得られ
たＢａ：Ｃａ：Ｃｕ比が 1:2:2の非晶質薄膜を、Ｔｌ2
Ｏ3 、ＢａＣｕＯ2 、Ｃａ2 ＣｕＯ3 、ＣｕＯからなる
混合粉末と同時に熱処理する。このとき、混合粉末のＴ
ｌ：Ｂａ：Ｃａ：Ｃｕの比を１：１：３：３とする。は
じめに、９００〜９３０℃で２〜１６分間アニールする
一段階の熱処理を行ったところ、９３０℃、８分間の場
合にｃ軸が基板に対して垂直に立ったＴｌ2 Ｂａ2 Ｃａ
2 Ｃｕ3 Ｏy 薄膜が得られた。しかし、この薄膜の表面
形態は、図２の光学顕微鏡写真に示すように非常に粗い
不均質なものであった。図２で板状に見えるのが "222
3" 相であることが、Ｘ線マイクロアナライザにより確
認された。"2223"相の結晶核生成が十分でないために "
2223" 相の板状結晶が点在してしまったものと考えられ
る。As shown in FIG. 1, the amorphous thin film having a Ba: Ca: Cu ratio of 1: 2: 2 obtained by the sputtering was converted to Tl 2
Heat treatment is performed simultaneously with a mixed powder of O 3 , BaCuO 2 , Ca 2 CuO 3 , and CuO. At this time, the T
The ratio of 1: Ba: Ca: Cu is 1: 1: 3: 3. First, a one-step heat treatment of annealing at 900 to 930 ° C. for 2 to 16 minutes was performed, and in the case of 930 ° C. for 8 minutes, Tl 2 Ba 2 Ca with the c-axis standing perpendicular to the substrate.
A 2 Cu 3 O y thin film was obtained. However, the surface morphology of this thin film was very rough and heterogeneous as shown in the optical micrograph of FIG. The plate-like shape in Figure 2 is "222
X-ray microanalyzer confirmed that it was 3 "phase." 2223 "phase did not have enough crystal nuclei,
It is thought that plate-like crystals of the 2223 "phase were scattered.
【００１８】次に、９００℃で４分〜１２８時間アニー
ルする一段階熱処理を行った。この結果、"2223"相はＸ
線回折で小さなピーク強度でしか得られなかった。しか
し、小さくとも"2223"相のピークが観測できたことは、
９００℃において"2223"相の結晶核生成が可能であるこ
とを示唆している。Next, a one-step heat treatment of annealing at 900 ° C. for 4 minutes to 128 hours was performed. As a result, the “2223” phase becomes X
Only small peak intensities were obtained by line diffraction. However, the fact that the peak of the "2223" phase could be observed even if it was small,
It suggests that nucleation of the "2223" phase at 900 ° C. is possible.
【００１９】そこで、さらに９００℃、１〜１２８時間
のアニールと、さらに９３０℃、８分間のアニールを続
けて行う二段階熱処理を行った。９００℃の保持時間が
１〜８時間のとき、ｃ軸配向した"2223"薄膜が得られ
た。表面形態も一段階アニールのものと比べて格段に改
善されていた。特に８時間の場合には、針状および島状
の結晶がほとんど見られず互いに結合した板状の"2223"
相から成る均質な"2223"薄膜が得られた。Therefore, a two-stage heat treatment was performed in which annealing at 900 ° C. for 1 to 128 hours and annealing at 930 ° C. for 8 minutes were continued. When the holding time at 900 ° C. was 1 to 8 hours, a c-axis oriented “2223” thin film was obtained. The surface morphology was also significantly improved compared to the one-step annealing. In particular, in the case of 8 hours, needle-like and island-like crystals were hardly observed, and plate-like "2223" bonded to each other
A homogeneous "2223" thin film consisting of phases was obtained.
【００２０】９００℃、８時間、９３０℃、８分間の二
段階熱処理によって得られた膜の表面の光学顕微鏡写真
を図３に示す。熱処理後の混合粉末には"2223"相が生成
していた。この結果から、混合粉末はＴｌをＢａ−Ｃａ
−Ｃｕ−Ｏ薄膜に供給すると同時に自らはＴｌ2 Ｂａ2
Ｃａ2 Ｃｕ3 Ｏy となり、熱処理の終盤では"2223"相の
Ｔｌ平衡蒸気圧で薄膜をアニールしていたことを示して
いる。この膜の電気抵抗の温度依存性を直流四端子法で
測定したところ、１１７Ｋで抵抗がゼロになった。FIG. 3 shows an optical micrograph of the surface of the film obtained by the two-step heat treatment at 900 ° C. for 8 hours and 930 ° C. for 8 minutes. "2223" phase was formed in the mixed powder after the heat treatment. From this result, the mixed powder was converted from Tl to Ba-Ca
-While supplying to the Cu-O thin film, Tl 2 Ba 2
Ca 2 Cu 3 O y was obtained, indicating that the thin film was annealed at the Tl equilibrium vapor pressure of the “2223” phase at the end of the heat treatment. When the temperature dependence of the electrical resistance of this film was measured by the DC four-terminal method, the resistance became zero at 117K.
【００２１】以上説明した通り、本実施例によれば、Ｂ
ａ、Ｃａ、Ｃｕおよび酸素を含む薄膜を、Ｔｌ2 Ｏ3 、
ＢａＣｕＯ2 、Ｃａ2 ＣｕＯ3 、ＣｕＯから成る混合粉
末と同時に熱処理することにより、Ｔｌに触れる工程を
できるだけ少なくし、再現性よくＴｌ−Ｂａ−Ｃａ−Ｃ
ｕ−Ｏ薄膜が製造できた。また、混合粉末のＴｌ：Ｂ
ａ：Ｃａ：Ｃｕの比を１：１：３：３とし、酸素雰囲気
中で９００℃および９３０℃における二段階の熱処理を
行なうことにより再現性よく均質なＴｌ2 Ｂａ2 Ｃａ2
Ｃｕ3 Ｏy 薄膜が製造できた。混合粉末はＴｌを供給す
ると同時に、自らは"2223"相となり熱処理の終盤では"2
223"相のＴｌ平衡蒸気圧で薄膜をアニールする役目を果
たすと思われる。As described above, according to the present embodiment, B
a, a thin film containing Ca, Cu and oxygen is converted to Tl 2 O 3 ,
By performing a heat treatment simultaneously with the mixed powder composed of BaCuO 2 , Ca 2 CuO 3 , and CuO, the process of touching Tl is reduced as much as possible, and Tl—Ba—Ca—C is reproducibly obtained.
A uO thin film was manufactured. In addition, Tl: B of the mixed powder
The ratio of a: Ca: Cu is set to 1: 1: 3: 3, and a two-stage heat treatment is performed at 900 ° C. and 930 ° C. in an oxygen atmosphere to obtain a homogeneous Tl 2 Ba 2 Ca 2 with good reproducibility.
A Cu 3 O y thin film was produced. At the same time that the mixed powder supplies Tl, the mixed powder itself becomes the "2223" phase and "2"
It appears to serve to anneal the thin film at the Tl equilibrium vapor pressure of the 223 "phase.
【００２２】[0022]
【発明の効果】前記したとおり本発明によれば、Ｂａ、
Ｃａ、Ｃｕおよび酸素を含む薄膜を、Ｔｌ2 Ｏ3 、Ｂａ
ＣｕＯ2 、Ｃａ2 ＣｕＯ3 、ＣｕＯからなる混合粉末と
同時に熱処理することにより、Ｔｌに触れる工程をなる
べく増やさずに、再現性よくＴｌ−Ｂａ−Ｃａ−Ｃｕ−
Ｏ系酸化物超伝導体薄膜が製造できるという顕著な効果
を奏する。As described above, according to the present invention, Ba,
A thin film containing Ca, Cu and oxygen is converted to Tl 2 O 3 , Ba
By performing heat treatment simultaneously with the mixed powder of CuO 2 , Ca 2 CuO 3 , and CuO, Tl—Ba—Ca—Cu— is obtained with good reproducibility without increasing the step of touching Tl as much as possible.
This has a remarkable effect that an O-based oxide superconductor thin film can be manufactured.
【００２３】次に、混合粉末の（Ｔｌ＋Ｂａ＋Ｃａ＋Ｃ
ｕ）に対する（Ｃａ＋Ｃｕ）の割合が、５５〜８５モル
％であるという本発明の好ましい構成によれば、より優
れた特性の酸化物超伝導体薄膜が製造できる。Next, the mixed powder (Tl + Ba + Ca + C
According to the preferred configuration of the present invention in which the ratio of (Ca + Cu) to u) is 55 to 85 mol%, an oxide superconductor thin film having more excellent characteristics can be manufactured.
【００２４】また、熱処理が酸素雰囲気中で二段階の熱
処理であるという本発明の好ましい構成によれば、より
優れた特性の酸化物超伝導体薄膜が製造できる。Further, according to the preferred configuration of the present invention in which the heat treatment is a two-stage heat treatment in an oxygen atmosphere, an oxide superconductor thin film having more excellent characteristics can be manufactured.
【図１】Ｔｌを導入するための熱処理用管状電気炉の概
略断面図である。FIG. 1 is a schematic cross-sectional view of a tubular electric furnace for heat treatment for introducing Tl.
【図２】９３０℃、８分間の一段階熱処理によって得ら
れた薄膜の表面の粒子構造を示す図面に代わる光学顕微
鏡写真である（倍率：９００倍）。FIG. 2 is an optical microscope photograph (magnification: 900 times) showing a particle structure on the surface of a thin film obtained by one-step heat treatment at 930 ° C. for 8 minutes (magnification: 900 times).
【図３】９００℃、８時間、９３０℃、８分間の二段階
熱処理によって得られた薄膜の表面の粒子構造を示す図
面に代わる光学顕微鏡写真である（倍率：２３０倍）。FIG. 3 is an optical microscope photograph (magnification: 230 ×) showing a grain structure on the surface of a thin film obtained by a two-step heat treatment at 900 ° C. for 8 hours and 930 ° C. for 8 minutes.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 瀬恒 謙太郎 大阪府門真市大字門真1006番地 松下電 器産業株式会社内 (56)参考文献 特開 平２−201976（ＪＰ，Ａ) 特開 平２−159364（ＪＰ，Ａ) 特開 平２−188462（ＪＰ，Ａ) 特開 平２−97421（ＪＰ，Ａ) 特開 平３−218922（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) C01G 1/00 - 57/00 H01L 39/00 - 39/24────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Kentaro Seto 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-2-201976 (JP, A) JP-A-2 JP-A-159364 (JP, A) JP-A-2-188462 (JP, A) JP-A-2-97421 (JP, A) JP-A-3-218922 (JP, A) (58) Fields investigated (Int. . 6, DB name) C01G 1/00 - 57/00 H01L 39/00 - 39/24
Claims (3)
伝導体薄膜の製造方法において、Ｂａ、Ｃａ、Ｃｕおよ
び酸素を含む薄膜を、Ｔｌ2 Ｏ3、ＢａＣｕＯ2 、Ｃａ
2 ＣｕＯ3 、ＣｕＯからなる混合粉末と同時に熱処理す
ることを特徴とする酸化物超伝導薄膜の製造方法。In a method for producing a Tl—Ba—Ca—Cu—O-based oxide superconductor thin film, a thin film containing Ba, Ca, Cu and oxygen is replaced with Tl 2 O 3 , BaCuO 2 , Ca
(2) A method for producing an oxide superconducting thin film, wherein a heat treatment is performed simultaneously with a mixed powder comprising CuO 3 and CuO.
に対する（Ｃａ＋Ｃｕ）の割合が、５５〜８５モル％で
ある請求項１記載の酸化物超伝導薄膜の製造方法。2. The mixed powder (Tl + Ba + Ca + Cu)
The method for producing an oxide superconducting thin film according to claim 1, wherein the ratio of (Ca + Cu) to the total is 55 to 85 mol%.
理である請求項１記載の酸化物超伝導薄膜の製造方法。3. The method according to claim 1, wherein the heat treatment is a two-stage heat treatment in an oxygen atmosphere.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3074677A JP2840475B2 (en) | 1991-03-13 | 1991-03-13 | Method for producing oxide superconducting thin film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3074677A JP2840475B2 (en) | 1991-03-13 | 1991-03-13 | Method for producing oxide superconducting thin film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04285010A JPH04285010A (en) | 1992-10-09 |
| JP2840475B2 true JP2840475B2 (en) | 1998-12-24 |
Family
ID=13554101
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3074677A Expired - Fee Related JP2840475B2 (en) | 1991-03-13 | 1991-03-13 | Method for producing oxide superconducting thin film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2840475B2 (en) |
-
1991
- 1991-03-13 JP JP3074677A patent/JP2840475B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04285010A (en) | 1992-10-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2840475B2 (en) | Method for producing oxide superconducting thin film | |
| JPH02167820A (en) | Method for forming tl-base multiple oxide superconducting thin film | |
| JPH01100022A (en) | Preparation of superconducting thin film | |
| JPH01167221A (en) | Production of superconducting thin film | |
| US5206214A (en) | Method of preparing thin film of superconductor | |
| JP2544759B2 (en) | How to make a superconducting thin film | |
| EP0641750B1 (en) | Metallic oxide and process for manufacturing the same | |
| US5244868A (en) | Method of making high Tc superconductor material, and article produced by the method | |
| EP0430568B1 (en) | Method of making high Tc superconductor material, and article produced by the method | |
| JP2645730B2 (en) | Superconducting thin film | |
| JP3536920B2 (en) | Alloy superconductor and method of manufacturing the same | |
| JPH04357161A (en) | Oxide superconductor material and its production | |
| JP2545422B2 (en) | Composite oxide superconducting thin film and method for producing the same | |
| JP2817170B2 (en) | Manufacturing method of superconducting material | |
| JP2544761B2 (en) | Preparation method of superconducting thin film | |
| JP2590370B2 (en) | Superconducting material and manufacturing method thereof | |
| JP2545423B2 (en) | Composite oxide superconducting thin film and method for producing the same | |
| JPH0829938B2 (en) | Composite oxide superconducting thin film and method for producing the same | |
| JP2544760B2 (en) | Preparation method of superconducting thin film | |
| JPH01176216A (en) | Production of superconducting thin film of compound oxide | |
| JP3247914B2 (en) | Metal oxide material | |
| Provenzano et al. | Preliminary studies for the development of superconducting composite wires | |
| Kamino et al. | Formation of a superconducting YbBa2Cu3Ox phase on an insulating Yb2BaCuO5 substrate prepared by the PMQ method | |
| JPH02390A (en) | Semiconductor substrate with superconductor layer | |
| JPH06196760A (en) | Superconductive lamination thin film |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |