JP2774576B2 - Superconductor device and method of manufacturing the same - Google Patents
Superconductor device and method of manufacturing the sameInfo
- Publication number
- JP2774576B2 JP2774576B2 JP1142771A JP14277189A JP2774576B2 JP 2774576 B2 JP2774576 B2 JP 2774576B2 JP 1142771 A JP1142771 A JP 1142771A JP 14277189 A JP14277189 A JP 14277189A JP 2774576 B2 JP2774576 B2 JP 2774576B2
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- single crystal
- substrate
- film
- microbridge
- 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
- 239000002887 superconductor Substances 0.000 title claims description 52
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 239000010409 thin film Substances 0.000 claims description 36
- 239000010408 film Substances 0.000 claims description 35
- 239000000758 substrate Substances 0.000 claims description 35
- 239000013078 crystal Substances 0.000 claims description 33
- 238000000034 method Methods 0.000 claims description 22
- 239000004065 semiconductor Substances 0.000 claims description 14
- 238000005530 etching Methods 0.000 claims description 9
- 238000005566 electron beam evaporation Methods 0.000 claims description 5
- 239000012212 insulator Substances 0.000 claims description 4
- 238000005546 reactive sputtering Methods 0.000 claims description 3
- 238000000151 deposition Methods 0.000 description 7
- 230000008021 deposition Effects 0.000 description 4
- 230000006866 deterioration Effects 0.000 description 4
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 4
- 238000000059 patterning Methods 0.000 description 4
- 229910001233 yttria-stabilized zirconia Inorganic materials 0.000 description 4
- 238000004544 sputter deposition Methods 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- 239000011229 interlayer Substances 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 239000001301 oxygen Substances 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 238000001020 plasma etching Methods 0.000 description 2
- 229910002367 SrTiO Inorganic materials 0.000 description 1
- 239000012300 argon atmosphere Substances 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000010884 ion-beam technique Methods 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000005268 plasma chemical vapour deposition Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
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
Landscapes
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
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、超小型の超伝導体装置を作成する技術に係
わり、特に酸化物超伝導体を用いた超伝導体装置及びそ
の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a technique for producing a super-small superconductor device, and in particular, a superconductor device using an oxide superconductor. And its manufacturing method.
（従来の技術） 従来、低温超伝導体を用いた素子としては、トンネル
接合形のジョセフソン素子が広く知られている。この素
子は、絶縁物の厚さが超伝導体のコヒーレンス長程度で
あることが要求される。(Prior Art) Conventionally, a tunnel junction type Josephson element has been widely known as an element using a low-temperature superconductor. This device requires that the thickness of the insulator is about the coherence length of the superconductor.
一方、高温酸化物超伝導体を用いた素子では、ｃ軸配
向膜を用いると、そのコヒーレンス長は〜５Å程度であ
り、このような素子を作ることは、現在のところ容易で
はない。従って、コヒーレンス長よりも十分に長い幅を
持つマイクロブリッジ素子で見られるジョセフソン的特
性を用いることが必要である。On the other hand, in a device using a high-temperature oxide superconductor, if a c-axis alignment film is used, its coherence length is about 5 °, and it is not easy at present to produce such a device. Therefore, it is necessary to use Josephson-like characteristics found in a microbridge element having a width sufficiently longer than the coherence length.
マイクロブリッジ素子において、現在報告されている
主たる77K動作のジョセフソン接合は、酸化物基板上に
作成された多結晶Ba2YCu3OX等の酸化物超伝導体薄膜
を、数10μｍオーダーでマイクロブリッジに加工し、そ
のマイクロブリッジに弱いジョセフソン接合している結
晶粒界を２〜４個含んでいるものである。The main reported Josephson junction operating at 77K in micro-bridge devices is a micro-junction made of an oxide superconductor thin film such as polycrystalline Ba 2 YCu 3 O X formed on an oxide substrate in the order of several tens of μm. The microbridge is processed into a bridge and contains two to four crystal grain boundaries that are weakly Josephson-bonded to the microbridge.
また、製造技術を見た場合、酸化物超伝導体をマイク
ロブリッジに加工する方法として、SrTiO3,MgO等の酸化
物基板上に酸化物超伝導体膜を堆積した後、反応性イオ
ンエッチング，集束イオンビーム或いはエキシマレーザ
等を用いて、素子以外の不要の領域の超伝導体薄膜をエ
ッチング除去する方法が採られている。In view of the manufacturing technology, as a method of processing an oxide superconductor into a microbridge, an oxide superconductor film is deposited on an oxide substrate such as SrTiO 3 or MgO, and then reactive ion etching, A method has been adopted in which a superconducting thin film in an unnecessary area other than the element is removed by etching using a focused ion beam or an excimer laser.
ところで、この種の酸化物超伝導体素子にあっては次
のような問題がある。即ち、結晶粒界の弱いジョセフソ
ン接合を用いた場合は超伝導臨界電流密度が制限され、
また結晶粒界を用いているためジョセフソン特性の制御
性に乏しい。また、製造技術としては、酸化物超伝導体
薄膜を堆積した後にエッチング加工しているので、超伝
導体薄膜にダメージが生じ、超伝導特性の劣化を招き易
い。さらに、従来の酸化物超伝導体素子は、酸化物基板
上に形成されているため、現在広く使われている半導体
集積回路素子との一体性がないという欠点があった。Incidentally, this kind of oxide superconductor element has the following problems. That is, when a Josephson junction having a weak grain boundary is used, the superconducting critical current density is limited,
In addition, controllability of Josephson characteristics is poor due to the use of crystal grain boundaries. Further, as a manufacturing technique, since the oxide superconductor thin film is etched after being deposited, the superconductor thin film is damaged, and the superconductivity is likely to be deteriorated. Furthermore, since the conventional oxide superconductor element is formed on an oxide substrate, it has a disadvantage that it is not integrated with a semiconductor integrated circuit element which is widely used at present.
（発明が解決しようとする課題） このように従来の酸化物超伝導体素子にあっては、結
晶粒界の弱いジョセフソン接合を用いているため、超伝
導臨界電流密度が制限されるという問題があった。さら
に、酸化物超伝導体薄膜のエッチング加工により薄膜に
ダメージが発生するので、超伝導特性の劣化を招く問題
があった。(Problems to be Solved by the Invention) As described above, in the conventional oxide superconductor element, since a Josephson junction having a weak crystal grain boundary is used, there is a problem that the superconducting critical current density is limited. was there. Further, since the oxide superconductor thin film is damaged by the etching process, there is a problem that the superconductivity is deteriorated.
本発明は、上記事情を考慮してなされたもので、その
目的とするところは、エッチング加工に伴う超伝導特性
の劣化を防止することができ、且つ超伝導臨界電流密度
を高くすることのできる超伝導体装置を提供することに
ある。The present invention has been made in view of the above circumstances, and aims at preventing deterioration of superconducting characteristics due to etching and increasing superconducting critical current density. It is to provide a superconductor device.
また本発明は、上記特長を有する超伝導体装置を簡易
に作成するための超伝導半導体体装置の製造方法を提供
することにある。Another object of the present invention is to provide a method for manufacturing a superconducting semiconductor device for easily producing a superconductor device having the above-mentioned features.
［発明の構成］ （課題を解決するための手段） 本発明の骨子は、基板としてSi等の半導体単結晶基板
を用い、この基板上に結晶粒界のない酸化物超伝導体単
結晶を形成することにある。[Constitution of the Invention] (Means for Solving the Problems) The gist of the present invention is that a semiconductor single crystal substrate such as Si is used as a substrate, and an oxide superconductor single crystal without a crystal grain boundary is formed on the substrate. Is to do.
即ち本発明は、酸化物超伝導体を用いたマイクロブリ
ッジ構造を有する超伝導体装置において、主表面の一部
を選択的にエッチングしてマイクロブリッジが形成され
た単結晶半導体基板と、この基板の主表面上に形成され
た単結晶絶縁膜と、この絶縁膜上に形成された酸化物超
伝導体薄膜とを具備してなるものである。That is, the present invention relates to a superconductor device having a microbridge structure using an oxide superconductor, wherein a single-crystal semiconductor substrate in which a microbridge is formed by selectively etching a part of a main surface; And a single crystal insulating film formed on the main surface of the above, and an oxide superconductor thin film formed on the insulating film.
また本発明は、上記超伝導体装置を製造する方法にお
いて、単結晶半導体基板の主表面上に電子ビーム蒸着法
等により単結晶絶縁膜をエピタキシャル成長したのち、
基板の主表面の一部を選択エッチングして溝を形成し、
該溝により幅が狭められたマイクロブリッジを形成し、
次いで絶縁膜上に反応性スパッタリング法等により酸化
物超伝導体薄膜をエピタキシャル成長するようにした方
法である。さらに本発明は、上記単結晶絶縁膜を成長す
る工程とマイクロブリッジを形成する工程との順序を逆
にした方法である。Further, according to the present invention, in the method for manufacturing a superconductor device, after the single crystal insulating film is epitaxially grown on the main surface of the single crystal semiconductor substrate by an electron beam evaporation method or the like,
Selectively etch a part of the main surface of the substrate to form a groove,
Form a microbridge narrowed by the groove,
Then, an oxide superconductor thin film is epitaxially grown on the insulating film by a reactive sputtering method or the like. Further, the present invention is a method in which the order of the step of growing the single crystal insulating film and the step of forming the microbridge are reversed.
（作用） 基板としてSi等の半導体単結晶基板を用いた場合、こ
の基板上にBa2YCu3OX等の酸化物超伝導体薄膜を形成し
ようとしても、該薄膜はエピタキシャル成長できず、ま
た形成されても単結晶にはならない。そこで本発明者等
は、単結晶半導体基板と酸化物超伝導体薄膜との間にこ
れらとは異なる薄膜を形成することにより、酸化物超伝
導体薄膜を単結晶化することを試みた。そして、各種の
薄膜を用いて実験を繰り返したところ、次のような事実
を見出した。(Function) When a semiconductor single crystal substrate such as Si is used as a substrate, even if an attempt is made to form an oxide superconductor thin film such as Ba 2 YCu 3 O X on this substrate, the thin film cannot be epitaxially grown and cannot be formed. However, it does not become a single crystal. Therefore, the present inventors have tried to monocrystallize the oxide superconductor thin film by forming a different thin film between the single crystal semiconductor substrate and the oxide superconductor thin film. When the experiment was repeated using various thin films, the following facts were found.
単結晶Si基板の表面に、真空中で電子ビーム蒸着法に
より、ZrO2或いはYSZ［イットリア安定化ジルコニア：
（ZrO2）0.91（Y2O3）0.09］を堆積すると、これらの絶
縁物はエピタキシャル成長して単結晶になる。さらに、
これらの絶縁物単結晶層上に反応性スパッタリング法に
よりBa2YCu3OX薄膜を堆積すると、該薄膜は結晶粒界の
ないエピタキシャル成長膜となっていることを見出し
た。また、単結晶Si基板に形成した溝の側壁部には、電
子ビーム蒸着法において、ZrO2,YSZは堆積したことを見
出した。本発明はこのような知見に基づいて前述した構
成及び工程を採用したものである。ZrO 2 or YSZ [Yttria-stabilized zirconia:
When (ZrO 2 ) 0.91 (Y 2 O 3 ) 0.09 ] is deposited, these insulators grow epitaxially into single crystals. further,
When a Ba 2 YCu 3 O X thin film was deposited on these insulator single crystal layers by a reactive sputtering method, the thin film was found to be an epitaxially grown film having no crystal grain boundaries. It was also found that ZrO 2 and YSZ were deposited on the side wall of the groove formed in the single crystal Si substrate by electron beam evaporation. The present invention employs the above-described configuration and steps based on such knowledge.
従って本発明によれば、結晶粒界のないマイクロブリ
ッジ素子が形成されることになり、従来技術のように、
結晶粒界の弱いジョセフソン接合を用いた素子の場合に
比べて、超伝導臨界電流密度が格段に高い。一方、製造
技術としては、酸化物超伝導体薄膜形成前に、マスクロ
ブリッジ形成のためのパターニングが施されるので、パ
ターニングによる酸化物超伝導体薄膜の膜質劣化を未然
に防止することができる。また、基板としてSi等の半導
体基板を用いるので、現在広く使われている半導体集積
回路との一体性を高めることが可能となる。Therefore, according to the present invention, a microbridge element having no grain boundaries is formed, and as in the prior art,
The superconducting critical current density is much higher than that of a device using a Josephson junction having a weak crystal grain boundary. On the other hand, as a manufacturing technique, patterning for forming a masking bridge is performed before forming the oxide superconductor thin film, so that it is possible to prevent deterioration of the film quality of the oxide superconductor thin film due to the patterning. . In addition, since a semiconductor substrate such as Si is used as the substrate, it is possible to enhance the integration with a semiconductor integrated circuit that is currently widely used.
（実施例） 以下、本発明の詳細を図示の実施例によって説明す
る。(Examples) Hereinafter, details of the present invention will be described with reference to the illustrated examples.
第１図は本発明の一実施例に係わるマイクロブリッジ
素子の製造工程を示す斜視図である。FIG. 1 is a perspective view showing a manufacturing process of a microbridge device according to one embodiment of the present invention.
まず、第１図（ａ）に示す如く、ｐ形単結晶Si基板11
の（100）配向の主面に、レジストマスク（図示せず）
を用いた反応性イオンエッチング法により、深さ３μｍ
の溝12を掘り、幅0.5μm,長さ１μｍのマイクロブリッ
ジ13を形成する。ここで、第１図（ａ）では基板11を溝
により複数の島に分離した島状領域の一つを示してい
る。First, as shown in FIG. 1 (a), a p-type single crystal Si substrate 11 is formed.
A resist mask (not shown) on the (100) oriented main surface
3 μm depth by reactive ion etching using
The micro bridge 13 having a width of 0.5 μm and a length of 1 μm is formed. Here, FIG. 1 (a) shows one of the island regions where the substrate 11 is divided into a plurality of islands by grooves.
次いで、Si基板11を真空中で800℃に加熱し、真空度
１×10-3Paの状態で電子ビーム蒸着法により、第１図
（ｂ）に示す如くZrO2膜14を0.1μｍの厚さにエピタキ
シャル成長させる。このとき、ZrO2膜14は基板11の表面
及び溝12の底壁には堆積するが、溝の側壁には堆積しな
い。これは、電子ビーム蒸着法を用いて方向性のある堆
積を行ったからと考えられる。なお、ZrO2膜14の堆積に
は必ずしもビーム蒸着法を用いる必要はなく、Si基板11
上に単結晶のZrO2膜を方向性を持って成長できる方法で
あれば使用することが可能である。Next, the Si substrate 11 is heated to 800 ° C. in vacuum, and the ZrO 2 film 14 is formed to a thickness of 0.1 μm by an electron beam evaporation method at a degree of vacuum of 1 × 10 −3 Pa as shown in FIG. Then, epitaxial growth is performed. At this time, the ZrO 2 film 14 is deposited on the surface of the substrate 11 and the bottom wall of the groove 12, but is not deposited on the side wall of the groove. This is probably because the directional deposition was performed using the electron beam evaporation method. Note that it is not always necessary to use the beam evaporation method for depositing the ZrO 2 film 14, and the Si substrate 11
Any method can be used as long as it can grow a single-crystal ZrO 2 film with directionality on it.
次いで、第１図（ｃ）に示す如く、 Ba2YCu3OX超伝導体薄膜15を0.2μｍの厚さに、高周波マ
グネトロンスパッタリング法を用いて、ZrO2膜14上にエ
ピタキシャル成長させる。このとき。Si基板11を通電加
熱により700℃に保持した。スパッタリングに用いた超
伝導体ターゲットは、BaCO3,Y2O3及びCuOパウダーを酸
素雰囲気中で900℃,8時間熱処理したものである。スパ
ッタリングは、酸素を50％含む超高純度アルゴン雰囲気
中（圧力1Pa）で行い、基板11を設置した放電電極には5
0Vの正バイアスを加え、成長される薄膜15が荷電粒子の
衝突に晒されることを防いだ。超伝導体薄膜15の堆積速
度は30Å/minであった。Next, as shown in FIG. 1C, a Ba 2 YCu 3 O X superconductor thin film 15 is epitaxially grown to a thickness of 0.2 μm on the ZrO 2 film 14 by using a high-frequency magnetron sputtering method. At this time. The Si substrate 11 was kept at 700 ° C. by applying electric current. The superconductor target used for sputtering is obtained by heat-treating BaCO 3 , Y 2 O 3 and CuO powder in an oxygen atmosphere at 900 ° C. for 8 hours. Sputtering was performed in an ultra-high purity argon atmosphere containing 50% oxygen (pressure 1 Pa).
A positive bias of 0 V was applied to prevent the growing thin film 15 from being exposed to charged particle bombardment. The deposition rate of the superconductor thin film 15 was 30 ° / min.
また、Si基板11の表面には薄膜15は堆積せず、ZrO2膜
14の表面のみに堆積するので、超伝導体薄膜15はZrO2膜
14と同様に溝12の側壁には堆積されない。なお、超伝導
体薄膜15の堆積には必ずしも反応性イオンスパッタリン
グ法を用いる必要はなく、ZrO2膜の上にエピタキシャル
成長できる方法であれば使用することが可能である。Further, the thin film 15 is not deposited on the surface of the Si substrate 11, and the ZrO 2 film
Since it is deposited only on the surface of 14, the superconductor thin film 15 is a ZrO 2 film
Like 14, it is not deposited on the side walls of groove 12. It is not always necessary to use the reactive ion sputtering method for depositing the superconductor thin film 15, but any method that can epitaxially grow on the ZrO 2 film can be used.
次いで、第１図（ｄ）に示す如く、Si3N4膜16を基板
温度300℃で、プラズマCVD法により0.3μｍの厚さに全
面に堆積した後、レジストマスク（図示せず）を用いて
電極コンタクト孔17a,17bを形成する。最後に、第１図
（ｅ）に示す如く、マイクロブリッジで接続された２つ
の領域にそれぞれ接続されるAg電極18a,18bを形成す
る。Next, as shown in FIG. 1 (d), a Si 3 N 4 film 16 is deposited over the entire surface at a substrate temperature of 300 ° C. to a thickness of 0.3 μm by a plasma CVD method, and then a resist mask (not shown) is used. Then, electrode contact holes 17a and 17b are formed. Finally, as shown in FIG. 1E, Ag electrodes 18a and 18b connected to the two regions connected by the microbridge are formed.
かくして形成されたマイクロブリッジ素子の超伝導臨
界電流密度は、50Kで１×105A/cm2であった。また、10G
Hzのマイクロ波に対して、電流源バイアスしたマイクロ
ブリッジのＩ−Ｖ特性には、測定温度50Kで、第２図に
示すようなシャピロステップが観測され、作成したマイ
クロブリッジ素子がジョセフソン接合していることが確
認された。なお、第２図において実線はマイクロ波を印
加したとき、破線はマイクロ波を印加しない時のＩ−Ｖ
特性を示している。また、第１図（ｅ）に示されるマイ
クロブリッジ素子は、高感度の電波検知器や変調器とし
て用いることができる。The superconducting critical current density of the microbridge device thus formed was 1 × 10 5 A / cm 2 at 50K. Also, 10G
At the measurement temperature of 50 K, a Shapiro step as shown in FIG. 2 was observed in the IV characteristics of the microbridge subjected to the current source bias with respect to the microwave of Hz, and the fabricated microbridge element was subjected to a Josephson junction. It was confirmed that. In FIG. 2, the solid line indicates the case where microwaves were applied, and the broken line indicates the IV when no microwaves were applied.
The characteristics are shown. Further, the microbridge element shown in FIG. 1 (e) can be used as a highly sensitive radio wave detector or modulator.
このように本実施例によれば、マイクロブリッジ構造
を有する単結晶Si基板11上にZrO2膜14を介してBa2YCu3O
X超伝導体薄膜15を形成することにより、超伝導体薄膜1
5がエピタキシャル成長による単結晶層となるので、結
晶粒界のないマイクロブリッジ素子を作成することがで
きる。従って、結晶粒界の弱いジョセフソン接合を用い
た素子の場合に比べて、超伝導臨界電流密度を大幅に高
めることができる。また、超伝導体薄膜15の形成前に、
第１図（ａ）に示す工程でマイクロブリッジ形成のため
のパターニングが施されるので、パターニングによる超
伝導体薄膜15の膜質劣化を未然に防止することかでき
る。さらに、基板としてSi単結晶基板11を用いるので、
現在広く使われているSi半導体集積回路との一体性を高
めることが可能となる。As described above, according to the present embodiment, Ba 2 YCu 3 O is formed on the single crystal Si substrate 11 having the microbridge structure via the ZrO 2 film 14.
By forming the X superconductor thin film 15, the superconductor thin film 1
Since 5 is a single crystal layer formed by epitaxial growth, a microbridge element having no grain boundaries can be manufactured. Therefore, the superconducting critical current density can be greatly increased as compared with a device using a Josephson junction having a weak crystal grain boundary. Before forming the superconductor thin film 15,
Since the patterning for forming the microbridge is performed in the step shown in FIG. 1A, the deterioration of the superconductor thin film 15 due to the patterning can be prevented. Furthermore, since the Si single crystal substrate 11 is used as the substrate,
It becomes possible to enhance the integration with the Si semiconductor integrated circuit which is currently widely used.
なお、本発明は上述した実施例に限定されるものでは
ない。実施例では、Si基板と超伝導体薄膜の層間単結晶
絶縁膜として、ZrO2を用いたが、YSZを用いても同様の
効果が得られる。さらに、超伝導体薄膜と金属電極との
層間絶縁膜は、堆積温度が超伝導体薄膜の特性を変化さ
せないかぎり、Si3N4以外のものであってもよい。ま
た、絶縁膜，超伝導体薄膜の膜圧，堆積方法，堆積条件
等は、仕様に応じて適宜変更可能である。その他、本発
明の要旨を逸脱しない範囲で、種々変形して実施するこ
とができる。The present invention is not limited to the embodiments described above. In the embodiment, ZrO 2 is used as the interlayer single crystal insulating film between the Si substrate and the superconductor thin film, but the same effect can be obtained by using YSZ. Further, the interlayer insulating film between the superconductor thin film and the metal electrode may be other than Si 3 N 4 as long as the deposition temperature does not change the characteristics of the superconductor thin film. Further, the film pressure, the deposition method, the deposition conditions, etc. of the insulating film and the superconductor thin film can be appropriately changed according to the specifications. In addition, various modifications can be made without departing from the scope of the present invention.
［発明の効果］ 以上詳述したように本発明によれば、マイクロブリッ
ジの形成されたSi等の半導体単結晶基板を用い、この基
板上に単結晶絶縁膜を介して酸化物超伝導体を形成する
ことにより、エッチング加工の必要がなく、且つ結晶粒
界のない単結晶の酸化物超伝導体薄膜を形成することが
できる。従って、エッチング加工に伴う超伝導特性の劣
化を防止することができ、しかも超伝導臨界電流密度を
高くすることが可能となる。[Effects of the Invention] As described above in detail, according to the present invention, a semiconductor single crystal substrate such as Si having a microbridge formed thereon is used, and an oxide superconductor is formed on this substrate via a single crystal insulating film. By forming the oxide superconductor, a single crystal oxide superconductor thin film which does not require etching and has no crystal grain boundaries can be formed. Therefore, it is possible to prevent the deterioration of the superconducting characteristics due to the etching process, and it is possible to increase the superconducting critical current density.
第１図は本発明の一実施例に係わるマイクロブリッジ素
子の製造工程を示す斜視図、第２図は同実施例素子にお
けるマイクロブリッジ素子のＩ−Ｖ特性を示す図であ
る。 11……単結晶Si基板、 12……溝、 13……マイクロブリッジ、 14……ZrO2膜（単結晶絶縁膜）、 15……Ba2YCu3OX膜（酸化物超伝導体薄膜）、 16……Si3N4膜、 17a,17b……電極コンタクト孔、 18a,18b……Ag電極。FIG. 1 is a perspective view showing a manufacturing process of a microbridge device according to an embodiment of the present invention, and FIG. 2 is a diagram showing IV characteristics of the microbridge device in the embodiment device. 11: Single crystal Si substrate, 12: Groove, 13: Micro bridge, 14: ZrO 2 film (single crystal insulating film), 15: Ba 2 YCu 3 O X film (oxide superconductor thin film) , 16 ...... Si 3 N 4 film, 17a, 17b ...... electrode contact hole, 18a, 18b ...... Ag electrode.
Claims (4)
イクロブリッジが形成された単結晶半導体基板と、この
基板の主表面上に形成された単結晶絶縁膜と、この絶縁
膜上に形成された酸化物超伝導体薄膜とを具備してなる
ことを特徴とする超伝導体装置。1. A single crystal semiconductor substrate on which a microbridge is formed by selectively etching a part of a main surface, a single crystal insulating film formed on a main surface of the substrate, and a single crystal semiconductor film formed on the insulating film. A superconductor device comprising: a formed oxide superconductor thin film.
ングにより形成された溝内に、非結晶絶縁物が埋め込ま
れていることを特徴とする請求項１記載の超伝導体装
置。2. The superconductor device according to claim 1, wherein an amorphous insulator is buried in a groove formed by etching for forming the microbridge.
膜をエピタキシャル成長する工程と、前記絶縁膜を成長
する前又は成長した後に前記基板の主表面の一部を選択
エッチングして溝を形成し、該溝により幅が狭められた
マイクロブリッジを形成する工程と、次いで前記絶縁膜
上に酸化物超伝導体薄膜をエピタキシャル成長する工程
とを含むことを特徴とする超伝導体装置の製造方法。3. A step of epitaxially growing a single crystal insulating film on a main surface of a single crystal semiconductor substrate, and selectively etching a part of the main surface of the substrate before or after growing the insulating film to form a groove. Forming a microbridge whose width is reduced by the groove, and then epitaxially growing an oxide superconductor thin film on the insulating film. .
着法を用い、前記超伝導体薄膜の成長方法として反応性
スパッタリング法を用いたことを特徴とする請求項３記
載の超伝導体装置の製造方法。4. The superconductor device according to claim 3, wherein an electron beam evaporation method is used as a method of growing said insulating film, and a reactive sputtering method is used as a method of growing said superconductor thin film. Production method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1142771A JP2774576B2 (en) | 1989-06-05 | 1989-06-05 | Superconductor device and method of manufacturing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1142771A JP2774576B2 (en) | 1989-06-05 | 1989-06-05 | Superconductor device and method of manufacturing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH036873A JPH036873A (en) | 1991-01-14 |
| JP2774576B2 true JP2774576B2 (en) | 1998-07-09 |
Family
ID=15323206
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1142771A Expired - Fee Related JP2774576B2 (en) | 1989-06-05 | 1989-06-05 | Superconductor device and method of manufacturing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2774576B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113629181A (en) * | 2021-07-23 | 2021-11-09 | 中国科学院电工研究所 | MgB2Preparation method of superconducting microbridge |
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1989
- 1989-06-05 JP JP1142771A patent/JP2774576B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH036873A (en) | 1991-01-14 |
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