FR2641129A1 - Substrate for a superconducting thin film - Google Patents
Substrate for a superconducting thin film Download PDFInfo
- Publication number
- FR2641129A1 FR2641129A1 FR8817206A FR8817206A FR2641129A1 FR 2641129 A1 FR2641129 A1 FR 2641129A1 FR 8817206 A FR8817206 A FR 8817206A FR 8817206 A FR8817206 A FR 8817206A FR 2641129 A1 FR2641129 A1 FR 2641129A1
- Authority
- FR
- France
- Prior art keywords
- superconductive
- substrate
- oxide
- layer
- beryllium oxide
- 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.)
- Pending
Links
- 239000000758 substrate Substances 0.000 title claims abstract description 24
- 239000010409 thin film Substances 0.000 title abstract description 3
- LTPBRCUWZOMYOC-UHFFFAOYSA-N beryllium oxide Inorganic materials O=[Be] LTPBRCUWZOMYOC-UHFFFAOYSA-N 0.000 claims abstract description 19
- FRWYFWZENXDZMU-UHFFFAOYSA-N 2-iodoquinoline Chemical compound C1=CC=CC2=NC(I)=CC=C21 FRWYFWZENXDZMU-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910052727 yttrium Inorganic materials 0.000 claims description 7
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 claims description 7
- 229910002480 Cu-O Inorganic materials 0.000 claims description 2
- 229910052761 rare earth metal Chemical group 0.000 claims description 2
- 150000002910 rare earth metals Chemical group 0.000 claims description 2
- 229910052723 transition metal Inorganic materials 0.000 claims description 2
- 150000003624 transition metals Chemical group 0.000 claims description 2
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 238000009792 diffusion process Methods 0.000 description 3
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 2
- 229910001632 barium fluoride Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 239000010408 film Substances 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 229910002370 SrTiO3 Inorganic materials 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052788 barium Inorganic materials 0.000 description 1
- OYLGJCQECKOTOL-UHFFFAOYSA-L barium fluoride Chemical compound [F-].[F-].[Ba+2] OYLGJCQECKOTOL-UHFFFAOYSA-L 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- -1 copper metal oxides Chemical class 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000008021 deposition 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
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N60/00—Superconducting devices
- H10N60/01—Manufacture or treatment
- H10N60/0268—Manufacture or treatment of devices comprising copper oxide
- H10N60/0296—Processes for depositing or forming copper oxide superconductor layers
- H10N60/0576—Processes for depositing or forming copper oxide superconductor layers characterised by the substrate
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Superconductors And Manufacturing Methods Therefor (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
Abstract
Description
L'invention se rapporte aux dispositifs supraconducteurs du type incluant un substrat de support pour couches minces supraconductrices. L'invention
s'applique notamment aux couches minces supraconductrices à température critique élevée, c'est-à-dire proche ou supérieure à la température de
l'azote liquide (77 K). Les recherches actuelles sur de telles couches
s'intéressent aux oxydes supraconducteurs tels que les céramiques d'oxydes métalliques de cuivre alliés à divers composés, dont la formule chimique est de la forme R-Ba-Cu-O, où R est un métal de transition ou une terre rare. L'oxyde de ce type ayant servi d'exemple a pour formule YBa2Cu307.The invention relates to superconductive devices of the type including a support substrate for superconductive thin films. The invention
applies in particular to thin superconductive layers with a high critical temperature, that is to say close to or above the temperature of
liquid nitrogen (77 K). Current research on such layers
are interested in superconductive oxides such as ceramics of copper metal oxides alloyed with various compounds, whose chemical formula is of the form R-Ba-Cu-O, where R is a transition metal or a rare earth. The oxide of this type having served as an example has the formula YBa2Cu307.
L'invention vise plus particulièrement l'application des couches minces supraconductrices à l'industrie électronique. Dans ce domaine, il faut des couches de dimensions relativement grandes, pour servir par exemple à l'interconnexion de composants électroniques tels que des circuits intégrés d'un processeur central d'un ordinateur. Il faut en outre des couches présentant une densité de courant critique très élevée.The invention relates more particularly to the application of thin superconductive layers to the electronic industry. In this area, relatively large layers are needed, for example for the interconnection of electronic components such as integrated circuits of a central processor of a computer. In addition, layers with a very high critical current density are required.
La formation de couches minces supraconductrices s'est faite jusqu'à présent sur des substrats monocristallins. Naturellement, le silicium a ete utilisé. Les expériences sur le silicium ont révélé l'existence de nombreux problèmes. Parmi les autres matériaux monocristallins, les plus connus actuellement sont le titanate de strontium SrTiO3, la zircone stabilisée à l'yttrium ZrO2(Y2O3) et l'oxyde de magnésium MgO. Cependant, les expériences faites sur tous les substrats actuels posent les mêmes genres de problèmes.The formation of thin superconductive layers has so far been carried out on monocrystalline substrates. Naturally, silicon was used. Experiments on silicon have revealed the existence of many problems. Among the other monocrystalline materials, the best known currently are the strontium titanate SrTiO3, the zirconia stabilized with yttrium ZrO2 (Y2O3) and the magnesium oxide MgO. However, experiments on all current substrates pose the same kinds of problems.
Le problème essentiel concerne l'interaction entre éléments du substrat et éléments de la couche mince supraconductrice adjacente. Cette interaction est due à la diffusion ou migration d'éléments à travers l'interface substrat-couche et altère les propriétés semiconductrices de la couche mince. Elle doit donc être évitée ou réduite à une valeur négligeable.The main problem concerns the interaction between elements of the substrate and elements of the adjacent superconductive thin layer. This interaction is due to the diffusion or migration of elements through the substrate-layer interface and alters the semiconductor properties of the thin layer. It should therefore be avoided or reduced to a negligible value.
Cependant, la fabrication actuelle d'une couche supraconductrice sur un substrat pose d'importants problèmes de diffusion. Etant donné que la diffusion est proportionnelle à la température des matériaux, la formation actuelle d'une couche supraconductrice sur un substrat fait intervenir des températures relativement élevées, supérieures à 6000C. Le plus souvent, la fabrication d'un couche nécessite un recuit à une température égale ou supérieure à 850 C. Le problème se complique lorsque le matériau supraconducteur et le substrat sont tous deux des composés chimiques relativement complexes. Il faut alors qu'aucun des éléments du substrat ne puisse être réduit ou altéré chimiquement par les éléments de la couche déposée.Dans le cas de l'oxyde supraconducteur à base d'yttrium, de barium et de cuivre, par exemple l'oxyde YBa2Cu307, il faut notamment que le substrat ne puisse être chimiquement réduit par l'yttrium.However, the current manufacture of a superconductive layer on a substrate poses significant diffusion problems. Since the diffusion is proportional to the temperature of the materials, the current formation of a superconductive layer on a substrate involves relatively high temperatures, above 6000C. Most often, the production of a layer requires annealing at a temperature equal to or higher than 850 C. The problem is complicated when the superconductive material and the substrate are both relatively complex chemical compounds. It is then necessary that none of the elements of the substrate can be reduced or chemically altered by the elements of the deposited layer. In the case of the superconductive oxide based on yttrium, barium and copper, for example the oxide YBa2Cu307, in particular the substrate cannot be chemically reduced by yttrium.
Le second problème des substrats actuels est de nécessiter une structure monocristalline. Ces substrats sont coûteux, d'autant plus qu'ils font généralement intervenir des éléments rares. En outre, un cristal pur est difficile à obtenir pour des grandes dimensions qui sont requises par exemple pour l'interconnexion de composants électroniques.The second problem of current substrates is to require a monocrystalline structure. These substrates are expensive, especially since they generally involve rare elements. In addition, a pure crystal is difficult to obtain for large dimensions which are required for example for the interconnection of electronic components.
L'invention résoud ces problèmes et offre ainsi l'avantage d'obtenir une couche supraconductrice de l'ordre du micromètre, non altérée par le substrat et présentant une densité de courant critique actuellement au moins égale à 1000 A/cm2 à la température de l'hélium liquide.The invention solves these problems and thus offers the advantage of obtaining a superconductive layer of the order of a micrometer, not altered by the substrate and having a critical current density currently at least equal to 1000 A / cm 2 at the temperature of liquid helium.
Un substrat conforme à l'invention pour couche mince d'oxyde supraconducteur est caractérisé en ce qu'il comprend de l'oxyde de béryllium.A substrate according to the invention for a thin layer of superconductive oxide is characterized in that it comprises beryllium oxide.
Avantageusement, on utilisera l'oxyde de béryllium polycristallin.Advantageously, polycrystalline beryllium oxide will be used.
Les avantages et caractéristiques de l'invention ressortiront de la description qui suit, donnée à titre d'exemple et faite en référence aux dessins annexés.The advantages and characteristics of the invention will emerge from the description which follows, given by way of example and made with reference to the accompanying drawings.
Dans les dessins - la figure 1 est une vue schématique en coupe partielle d'un substrat conforme à l'invention, fait d'oxyde de béryllium polycristallin, supportant une couche mince supraconductrice d'YBa2Cu307 ; et - la figure 2 est un graphe illustrant les variations de la résistance électrique d'une couche supraconductrice en fonction de la variation de la température, obtenu à partir de la structure représentée sur la figure 1. In the drawings - Figure 1 is a schematic partial sectional view of a substrate according to the invention, made of polycrystalline beryllium oxide, supporting a thin superconductive layer of YBa2Cu307; and FIG. 2 is a graph illustrating the variations in the electrical resistance of a superconductive layer as a function of the variation in temperature, obtained from the structure shown in FIG. 1.
Dans la figure 1, le dispositif électronique 10 comprend un support 12 pour une couche mince supraconductrice 14. Selon l'invention, le substrat 12 comprend de l'oxyde de béryllium BeO. Dans l'exemple de réalisation, le substrat entier est de l'oxyde de béryllium polycristallin, et la couche supraconductrice 14 est de 1'YBa2Cu307. La couche 14 à été déposée selon une technologie bien connue de l'nomme de l'art. Le mode préféré est le dépôt au canon à électrons de couches successives de fluorure de barium
BaF2, de cuivre et d'yttrium en présence d'une faible pression d'oxygène.In FIG. 1, the electronic device 10 comprises a support 12 for a thin superconductive layer 14. According to the invention, the substrate 12 comprises beryllium oxide BeO. In the exemplary embodiment, the entire substrate is polycrystalline beryllium oxide, and the superconductive layer 14 is YBa2Cu307. The layer 14 has been deposited according to a technology well known to those skilled in the art. The preferred mode is the deposition with the electron gun of successive layers of barium fluoride
BaF2, copper and yttrium in the presence of low oxygen pressure.
Les épaisseurs de ces couches ont été calculées afin d'obtenir la stochiométrie désirée de deux atomes de barium et trois atomes de cuivre par atome d'yttrium. La figure 2 est la courbe expérimentale obtenue avec ltechantillon conforme à l'invention, ayant pour abscisses la température en kelvins et pour ordonnées une échelle relative de résistance. La courbe montre une température critique Tc de 73 K.The thicknesses of these layers were calculated in order to obtain the desired stochiometry of two barium atoms and three copper atoms per yttrium atom. FIG. 2 is the experimental curve obtained with the sample in accordance with the invention, having the temperature in kelvins on the abscissa and on the ordinate a relative resistance scale. The curve shows a critical temperature Tc of 73 K.
Pour cette application à 1'YBa2Cu307, on constate que l'oxyde de béryllium n'est pas réduit par l'yttrium et qu'il demeure un substrat entièrement passif vis-à-vis de la couche supraconductrice. Les remarquables propriétés de l'oxyde de béryllium ne peuvent pas encore être expliquées. Un autre avantage de l'oxyde de béryllium est d'être très stable vis-à-vis de 1 'humidité. En Ex outre, l'oxyde de béryllium polycristallin peut être appliqué à moindre prix pour des dimensions relativement grandes, de sorte qu'il est bien adapté pour l'interconnexion de composants électroniques.For this application to YBa2Cu307, it can be seen that the beryllium oxide is not reduced by the yttrium and that it remains an entirely passive substrate vis-à-vis the superconductive layer. The remarkable properties of beryllium oxide cannot yet be explained. Another advantage of beryllium oxide is that it is very stable against humidity. In addition, polycrystalline beryllium oxide can be applied inexpensively for relatively large dimensions, so that it is well suited for the interconnection of electronic components.
Cependant, pour de faibles dimensions, il peut être avantageux d'utiliser l'oxyde de béryllium monocristallin. Selon une autre variante, le substrat 12 peut avoir une structure composite, indiquée par un trait tireté dans la figure 1. Selon cette variante, le substrat 12 comprend un support 13 pourvu d'un film d'oxyde de béryllium 12a sous-jacent à la couche supraconductrice 14. Le film 12a constituerait ainsi une couche d'interface avec la couche. However, for small dimensions, it may be advantageous to use monocrystalline beryllium oxide. According to another variant, the substrate 12 can have a composite structure, indicated by a dashed line in FIG. 1. According to this variant, the substrate 12 comprises a support 13 provided with a beryllium oxide film 12a underlying the superconductive layer 14. The film 12a would thus constitute an interface layer with the layer.
Claims (8)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8817206A FR2641129A1 (en) | 1988-12-27 | 1988-12-27 | Substrate for a superconducting thin film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8817206A FR2641129A1 (en) | 1988-12-27 | 1988-12-27 | Substrate for a superconducting thin film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| FR2641129A1 true FR2641129A1 (en) | 1990-06-29 |
Family
ID=9373438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| FR8817206A Pending FR2641129A1 (en) | 1988-12-27 | 1988-12-27 | Substrate for a superconducting thin film |
Country Status (1)
| Country | Link |
|---|---|
| FR (1) | FR2641129A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7670893B2 (en) | 1992-04-08 | 2010-03-02 | Taiwan Semiconductor Manufacturing Co., Ltd. | Membrane IC fabrication |
| US7705466B2 (en) | 1997-04-04 | 2010-04-27 | Elm Technology Corporation | Three dimensional multi layer memory and control logic integrated circuit structure |
| US8080442B2 (en) | 2002-08-08 | 2011-12-20 | Elm Technology Corporation | Vertical system integration |
-
1988
- 1988-12-27 FR FR8817206A patent/FR2641129A1/en active Pending
Non-Patent Citations (3)
| Title |
|---|
| APPLIED PHYSICS LETTERS, vol. 53, no. 12, 19 septembre 1988, pages 1110-1112, American Institute of Physics, New York, US; M. SACCHI et al.: "High Tc superconductivity in Y-Ba-Cu-O screen-printed films" * |
| APPLIED PHYSICS LETTERS, vol. 54, no. 10, 6 mars 1989, pages 957-959, American Institute of Physics, New York, US; H.M. HSU et al.: "Dense Bl-Sr-Ca-Cu-O superconducting films prepared by spray pyrolysis" * |
| MODERN PHYSICS LETTERS B, vol. 3, no. 6, 20 avril 1989, pages 509-513, World Scientific Publishing Co., SG; B. DABROWSKI et al.: "Preparation of superconducting thick films of YBa2Cu3O7 by deposition of a superconducting precursor ink" * |
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7911012B2 (en) | 1992-04-08 | 2011-03-22 | Taiwan Semiconductor Manufacturing Co., Ltd. | Flexible and elastic dielectric integrated circuit |
| US7670893B2 (en) | 1992-04-08 | 2010-03-02 | Taiwan Semiconductor Manufacturing Co., Ltd. | Membrane IC fabrication |
| US7763948B2 (en) | 1992-04-08 | 2010-07-27 | Taiwan Semiconductor Manufacturing Co., Ltd. | Flexible and elastic dielectric integrated circuit |
| US7820469B2 (en) | 1992-04-08 | 2010-10-26 | Taiwan Semiconductor Manufacturing Co., Ltd. | Stress-controlled dielectric integrated circuit |
| US8410617B2 (en) | 1997-04-04 | 2013-04-02 | Elm Technology | Three dimensional structure memory |
| US8824159B2 (en) | 1997-04-04 | 2014-09-02 | Glenn J. Leedy | Three dimensional structure memory |
| US9401183B2 (en) | 1997-04-04 | 2016-07-26 | Glenn J. Leedy | Stacked integrated memory device |
| US8933570B2 (en) | 1997-04-04 | 2015-01-13 | Elm Technology Corp. | Three dimensional structure memory |
| US8288206B2 (en) | 1997-04-04 | 2012-10-16 | Elm Technology Corp | Three dimensional structure memory |
| US8318538B2 (en) | 1997-04-04 | 2012-11-27 | Elm Technology Corp. | Three dimensional structure memory |
| US7705466B2 (en) | 1997-04-04 | 2010-04-27 | Elm Technology Corporation | Three dimensional multi layer memory and control logic integrated circuit structure |
| US8928119B2 (en) | 1997-04-04 | 2015-01-06 | Glenn J. Leedy | Three dimensional structure memory |
| US8629542B2 (en) | 1997-04-04 | 2014-01-14 | Glenn J. Leedy | Three dimensional structure memory |
| US8796862B2 (en) | 1997-04-04 | 2014-08-05 | Glenn J Leedy | Three dimensional memory structure |
| US8035233B2 (en) * | 1997-04-04 | 2011-10-11 | Elm Technology Corporation | Adjacent substantially flexible substrates having integrated circuits that are bonded together by non-polymeric layer |
| US8841778B2 (en) | 1997-04-04 | 2014-09-23 | Glenn J Leedy | Three dimensional memory structure |
| US8907499B2 (en) | 1997-04-04 | 2014-12-09 | Glenn J Leedy | Three dimensional structure memory |
| US8587102B2 (en) | 2002-08-08 | 2013-11-19 | Glenn J Leedy | Vertical system integration |
| US8269327B2 (en) | 2002-08-08 | 2012-09-18 | Glenn J Leedy | Vertical system integration |
| US8080442B2 (en) | 2002-08-08 | 2011-12-20 | Elm Technology Corporation | Vertical system integration |
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