JP2517085B2 - Superconducting thin film - Google Patents
Superconducting thin filmInfo
- Publication number
- JP2517085B2 JP2517085B2 JP63291218A JP29121888A JP2517085B2 JP 2517085 B2 JP2517085 B2 JP 2517085B2 JP 63291218 A JP63291218 A JP 63291218A JP 29121888 A JP29121888 A JP 29121888A JP 2517085 B2 JP2517085 B2 JP 2517085B2
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- barium
- superconducting
- oxide
- silicon
- 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
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
Description
【発明の詳細な説明】 産業上の利用分野 本発明は、エトロニクス用素子に応用される超電導薄
膜、特にバリウムを含む酸化物超電導薄膜に関するもの
である。TECHNICAL FIELD The present invention relates to a superconducting thin film applied to an element for etronics, and more particularly to an oxide superconducting thin film containing barium.
従来の技術 Ｙ−Ba−Cu−Ｏ系が超電導転移温度90Kをこえる高温
の超電導体であることが最近提案された［M.K.Wu等，フ
ィジカル レビュー レターズ（Physical Review Lett
ers）Vol.58,No.9,908−910（1987）］。これにより液
体窒素の沸点（77K）よりも高くなったことで実用化が
有望となってきた。また、100K以上で超電導体となるBi
−Sr−Ca−Cu−Ｏ系材料やTl−Ba−Ca−Cu−Ｏ系材料が
相次いで発見された。これら酸化物超電導材料の超電導
機構の詳細は明かではないが、転移温度が室温以上に高
くなる可能性があり、高温超電導体として従来の２元系
化合物より、より有望な特性が期待される。Conventional Technology It has been recently proposed that the Y-Ba-Cu-O system is a high-temperature superconductor with a superconducting transition temperature of 90K or higher [MKWu et al., Physical Review Lett.
ers) Vol.58, No.9, 908-910 (1987)]. As a result, the boiling point of liquid nitrogen (77K) has been raised, making it practical. In addition, Bi that becomes a superconductor at 100 K or more
-Sr-Ca-Cu-O-based materials and Tl-Ba-Ca-Cu-O-based materials were discovered one after another. Although the details of the superconducting mechanism of these oxide superconducting materials are not clear, the transition temperature may be higher than room temperature, and more promising properties are expected as a high temperature superconductor than conventional binary compounds.
これら酸化物超電導材料をエレクトロニクス素子とし
て実用化する場合、薄膜化が強く要望される。特に、こ
の種の材料の半導体上への薄膜化は、超電導体素子と半
導体素子との集積化や配線などに利用することができる
だけでなく、超電導と半導体を用いた新しい素子を実現
する可能性もあり、その応用範囲は広い。このため、Si
基板上に超電導薄膜を形成する試みが行われている。When these oxide superconducting materials are put to practical use as electronic devices, thinning is strongly required. In particular, thinning of this type of material on semiconductors can be used not only for integration of superconductor elements and semiconductor elements, wiring, etc., but also for the realization of new elements using superconductivity and semiconductors. There is also a wide range of applications. Therefore, Si
Attempts have been made to form a superconducting thin film on a substrate.
発明が解決しょうとする課題 しかし、現在のところ、酸化物超電導薄膜を形成する
ためには、基板を600℃かそれ以上に上げる必要があ
る。このため、単結晶Si基板上に直接酸化物超電導体を
成膜しようした場合、酸化物超電導体の構成元素である
バリウムがシリコンと反応し第２図に示すように基板の
シリコンとの界面近傍に析出するため、緻密でかつ平坦
で特性の良好な超電導薄膜は形成されにくい。However, at present, in order to form an oxide superconducting thin film, it is necessary to raise the substrate to 600 ° C. or higher. For this reason, when an oxide superconductor is directly formed on a single crystal Si substrate, barium, which is a constituent element of the oxide superconductor, reacts with silicon and, as shown in FIG. 2, near the interface between the substrate and silicon. Therefore, it is difficult to form a dense, flat superconducting thin film with good characteristics.
課題を解決するための手段 シリコンとバリウムの反応を抑えるため、シリコン基
体上に、前記シリコン基体に接した第１の薄膜と、前記
第１の薄膜に接した第２の薄膜を具備した超電導薄膜に
おいて、前記第１の薄膜と第２の薄膜がバリウムを含む
同一の構成元素からなり、かつ少なくとも前記第２の薄
膜が超電導特性を示し、かつ前記第１の薄膜中のバリウ
ムの含有量が前記第２の薄膜中のバリウムの含有量より
も少なくなるような構成にする。Means for Solving the Problems A superconducting thin film having a first thin film in contact with the silicon substrate and a second thin film in contact with the first thin film on a silicon substrate in order to suppress the reaction between silicon and barium. In the above, the first thin film and the second thin film are made of the same constituent element containing barium, at least the second thin film exhibits superconducting properties, and the content of barium in the first thin film is the above-mentioned. The second thin film is made to have a content smaller than that of barium.
作用 シリコン上に、先ずバリウムの濃度が通常の酸化物超
電導体よりも少ない酸化物を形成するため基板のシリコ
ンとバリウムの反応を抑えることができる。このうえに
良好な超電導特性を示す組成の酸化物薄膜を形成するた
め、シリコン上に良好な超電導薄膜を容易に作成するこ
とができる。Action First, an oxide having a barium concentration lower than that of a normal oxide superconductor is formed on silicon, so that the reaction between silicon on the substrate and barium can be suppressed. Since an oxide thin film having a composition exhibiting good superconducting properties is formed on this, a good superconducting thin film can be easily formed on silicon.
実施例 本発明の実施例を図面を用いて説明する。Embodiment An embodiment of the present invention will be described with reference to the drawings.
シリコン基板11上に、第１の薄膜として例えば、Ｙ−
Ba−Cuからなる酸化物を、高周波プレナーマグネトロン
スパッタにより、焼結したYBa2Cu4 ． 5OxターゲットをAr
とO2の混合ガス雰囲気でスパッタリング蒸着する。この
ときのスパッタ条件は、ArとO2のガス混合比は1:3、混
合ガス圧力は0.4Pa、スパッタリング電力は130W、基体
温度は600℃であり、薄膜の膜厚は10nmである。この薄
膜12の組成Ｙ−Ba−Cuは、通常の良好な超電導特性を示
す組成である１−２−３に比べてバリウムの量がかなり
少なくなっている。As the first thin film on the silicon substrate 11, for example, Y-
Ba-Cu oxide was sintered by high frequency planar magnetron sputtering to YBa 2 Cu 4 . 5 O x Target Ar
And sputter deposition in a mixed gas atmosphere of O 2 and O 2 . The sputtering conditions at this time are as follows: the gas mixture ratio of Ar and O 2 is 1: 3, the mixed gas pressure is 0.4 Pa, the sputtering power is 130 W, the substrate temperature is 600 ° C., and the thin film thickness is 10 nm. The composition Y-Ba-Cu of the thin film 12 has a considerably smaller amount of barium than that of 1-2-3 which is a composition which normally shows good superconducting properties.
上記第１の薄膜12を付着させた後、ArとO2のガス混合
比だけを2:1に変えて第２の薄膜13を形成した。膜厚は
0.5μｍである。After depositing the first thin film 12, the second thin film 13 was formed by changing only the gas mixture ratio of Ar and O 2 to 2: 1. The film thickness is
It is 0.5 μm.
酸化膜13を形成後、500Paの酸素雰囲気中において室
温まで冷却し、大気中にて取り出した。この第２の薄膜
13の組成Ｙ−Ba−Cuはほぼ１−２−３であった。このよ
うにして得られた第２の薄膜13は超電導を示し、その転
移温度はオンセット89Kで、オフセット75Kであった。ま
た、バリウムはシリコンとの相互反応が抑制されてお
り、界面でのバリウムの析出はなかった。After forming the oxide film 13, it was cooled to room temperature in an oxygen atmosphere of 500 Pa and taken out in the air. This second thin film
The composition Y-Ba-Cu of 13 was about 1-2-3. The second thin film 13 thus obtained showed superconductivity, and its transition temperature was 89K onset and 75K offset. In addition, barium was inhibited from interacting with silicon, and barium was not deposited at the interface.
第１の薄膜及び第２の薄膜の構成元素として、Ｙ（イ
ットリウム）、Ba（バリウム）、Cu（銅）からなる酸化
物以外に、元素のモル比率が 0.5≦（Ａ＋Ba）/Cu≦2.5 であるＡ元素、Ba（バリウム）およびCu（銅）を含む酸
化物を用いてもよい。ここに、ＡはBi、Tl、Pb、Scおよ
びランタン系列元素（原子番号57〜71）のうち少なくと
も一種の元素を示す。また、バリウムを含む酸化物にお
いて、バリウムの一部をII a族の元素のうち少なくとも
一種の元素で置き換えた酸化物でもよい。As the constituent elements of the first thin film and the second thin film, in addition to an oxide composed of Y (yttrium), Ba (barium) and Cu (copper), the molar ratio of the elements is 0.5 ≦ (A + Ba) /Cu≦2.5. An oxide containing a certain element A, Ba (barium) and Cu (copper) may be used. Here, A represents at least one element of Bi, Tl, Pb, Sc and lanthanum series elements (atomic numbers 57 to 71). Further, in the oxide containing barium, an oxide in which part of barium is replaced with at least one element of the IIa group elements may be used.
発明の効果 本発明によりシリコン上に酸化物超電導薄膜を容易に
形成することができるため、超電導薄膜の基板としてMg
OやSrTiO3等の高価な基板でなく、安価で大面積の基板
であるシリコンを用いることができる。また、直接シリ
コン上に超電導薄膜を形成することができるため、シリ
コンと超電導との接合を用いた新しい機能素子を作成す
ることが可能となる。EFFECTS OF THE INVENTION According to the present invention, an oxide superconducting thin film can be easily formed on silicon.
It is possible to use silicon, which is an inexpensive and large-area substrate, instead of an expensive substrate such as O or SrTiO 3 . Further, since the superconducting thin film can be formed directly on silicon, it becomes possible to create a new functional element using a junction between silicon and superconducting.
第１図は本発明の一実施例の超電導体構造物の基本構成
図、第２図は従来のシリコン上の酸化物薄膜のオージェ
電子分光分析界面特性図である。 11……シリコン基体、12……第１の薄膜、13……第２の
薄膜。FIG. 1 is a basic configuration diagram of a superconductor structure of one embodiment of the present invention, and FIG. 2 is a Auger electron spectroscopic analysis interface characteristic diagram of a conventional oxide thin film on silicon. 11 ... Silicon substrate, 12 ... First thin film, 13 ... Second thin film.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭63−233069（ＪＰ，Ａ) Ａｐｐｌ．Ｐｈｙｓ．Ｌｅｔｔ．52 （14）（1988−４−４）Ｐ．1185−86 笛木和雄・北沢宏一編「酸化物超伝導 体の化学」（昭63−４−10）株式会社講 談社発行Ｐ．175−177 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-233069 (JP, A) Appl. Phys. Lett. 52 (14) (1988-4-4) P. 1185-86 Kazuo Fueki, Koichi Kitazawa "Chemistry of oxide superconductors" (SHO 63-4-10) Published by Kodansha Co., Ltd. 175-177
Claims (3)
した第１の薄膜と、前記第１の薄膜に接した第２の薄膜
を具備した超電導薄膜において、前記第１の薄膜と第２
の薄膜がバリウムを含む同一の構成元素からなり、かつ
少なくとも前記第２の薄膜が超電導特性を示し、かつ前
記第１の薄膜中のバリウムの含有量が前記第２の薄膜中
のバリウムの含有量よりも少ないことを特徴とする超電
導薄膜。1. A superconducting thin film comprising a first thin film in contact with the silicon substrate and a second thin film in contact with the first thin film on a silicon substrate, wherein the first thin film and the second thin film are provided.
Of the same constituent element containing barium, at least the second thin film exhibits superconducting properties, and the content of barium in the first thin film is the content of barium in the second thin film. Superconducting thin film characterized by less than.
て、元素のモル比率が 0.5≦（Ａ＋Ba）/Cu≦2.5 であるＡ元素、Ba（バリウム）およびCu（銅）を含む酸
化物を用いることを特徴とする特許請求の範囲第１項記
載の超電導薄膜。 ここに、ＡはBi、Tl、Pb、Sc、Ｙおよびランタン系列元
素（原子番号57〜71）のうち少なくとも一種の元素を示
す。2. Oxidation containing element A, Ba (barium) and Cu (copper), whose molar ratio is 0.5 ≦ (A + Ba) /Cu≦2.5, as constituent elements of the first thin film and the second thin film. The superconducting thin film according to claim 1, characterized in that an object is used. Here, A represents at least one element of Bi, Tl, Pb, Sc, Y and lanthanum series elements (atomic numbers 57 to 71).
の一部をII a族の元素のうち少なくとも一種の元素で置
き換えることを特徴とする特許請求の範囲第２項記載の
超電導薄膜。3. The superconducting thin film according to claim 2, wherein in the oxide containing barium, part of barium is replaced with at least one element of the IIa group elements.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63291218A JP2517085B2 (en) | 1988-11-17 | 1988-11-17 | Superconducting thin film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63291218A JP2517085B2 (en) | 1988-11-17 | 1988-11-17 | Superconducting thin film |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02137724A JPH02137724A (en) | 1990-05-28 |
| JP2517085B2 true JP2517085B2 (en) | 1996-07-24 |
Family
ID=17765998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63291218A Expired - Fee Related JP2517085B2 (en) | 1988-11-17 | 1988-11-17 | Superconducting thin film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2517085B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5457443A (en) * | 1992-03-30 | 1995-10-10 | Yazaki Corporation | Multifunctional combination switch |
| JP2570837Y2 (en) * | 1992-07-23 | 1998-05-13 | 矢崎総業株式会社 | Lever switch |
| JPH1125807A (en) * | 1997-06-30 | 1999-01-29 | Niles Parts Co Ltd | Structure of vehicular lever switch |
-
1988
- 1988-11-17 JP JP63291218A patent/JP2517085B2/en not_active Expired - Fee Related
Non-Patent Citations (2)
| Title |
|---|
| Ａｐｐｌ．Ｐｈｙｓ．Ｌｅｔｔ．５２（１４）（１９８８−４−４）Ｐ．１１８５−８６ |
| 笛木和雄・北沢宏一編「酸化物超伝導体の化学」（昭６３−４−１０）株式会社講談社発行Ｐ．１７５−１７７ |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02137724A (en) | 1990-05-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH07106883B2 (en) | Superconductor structure | |
| EP0430737B1 (en) | A superconducting thin film | |
| EP0327493B1 (en) | Epitaxial arrangement of high tc superconductors on silicon | |
| US5179070A (en) | Semiconductor substrate having a superconducting thin film with a buffer layer in between | |
| US5910662A (en) | Semiconductor substrate having a superconducting thin film | |
| JP2517085B2 (en) | Superconducting thin film | |
| EP0341148B1 (en) | A semiconductor substrate having a superconducting thin film | |
| EP0357500B1 (en) | Process for preparing a bismuth-type superconducting thin film | |
| US5221660A (en) | Semiconductor substrate having a superconducting thin film | |
| EP0323345B1 (en) | A semiconductor substrate having a superconducting thin film | |
| EP0323342B1 (en) | A semiconductor substrate having a superconducting thin film | |
| JP2797186B2 (en) | Semiconductor substrate having superconductor layer | |
| US5296455A (en) | Process for preparing superconductor of compound oxide of Bi-Sr-Ca-Cu system | |
| JPH01280380A (en) | Semiconductor substrate having superconductor layer | |
| US5362709A (en) | Superconducting device | |
| JP3058515B2 (en) | Superconducting Josephson device and its manufacturing method | |
| JPH01280382A (en) | Semiconductor substrate having superconductor layer | |
| JPH01280376A (en) | Semiconductor substrate having superconductor layer | |
| JPH01280379A (en) | Semiconductor substrate having superconductor layer | |
| JPH01280377A (en) | Semiconductor substrate having superconductor layer | |
| JPH01280378A (en) | Semiconductor substrate having superconductor layer | |
| JPH01280373A (en) | Semiconductor substrate having superconductor layer | |
| JPH01280374A (en) | Semiconductor substrate having superconductor layer | |
| Zhao et al. | Sn doped Bi-Sr-Ca-Cu-O thin film | |
| JPH01280370A (en) | Semiconductor substrate having superconductor layer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |