Abstract: A process for formulating non-hysteretic and hysteretic Josephson junctions using HTS materials which results in junctions having the ability to operate at high temperatures while maintaining high uniformity and quality. The non-hysteretic Josephson junction is formed by step-etching a LaAlO.sub.3 crystal substrate and then depositing a thin film of TlCaBaCuO on the substrate, covering the step, and forming a grain boundary at the step and a subsequent Josephson junction. Once the non-hysteretic junction is formed the next step to form the hysteretic Josephson junction is to add capacitance to the system. In the current embodiment, this is accomplished by adding a thin dielectric layer, LaA1O.sub.3, followed by a cap layer of a normal metal where the cap layer is formed by first depositing a thin layer of titanium (Ti) followed by a layer of gold (Au). The dielectric layer and the normal metal cap are patterned to the desired geometry.

Abstract: An evaporation method of producing a new high Tc superconducting material using fullerene molecules as artificial pinning sites for any magnetic flux that may enter the material.

Abstract: An electrode in an electronic device using a functional thin film facilitates epitaxial growth during the functional material film-forming process and prevents the generation of cracks due to thermal stress. An oxide superconductor is using as an electrode material, thereby forming the crystal structure identical with the crystal structure of a functional thin film, and rendering their lattice constant and coefficient of thermal expansion close to the lattice constant and coefficient of thermal expansion functional thin film. According to the electrode material, high electric conductivity, low thermal conductivity and large thermal absorption coefficient characteristics can also be obtained.

Abstract: The present invention relates to the formation of a class of nanocomposite amorphous materials consisting of interpenetrating random networks of predominantly sp3 bonded carbon stabilized by hydrogen, glass-like silicon stabilized by oxygen and random networks of elements from the 1-7b and 8 groups of the periodic table. The materials have high strength and microhardness, flexibility, low coefficient of friction and high thermal and chemical stability. Nanocomposites containing networks of metallic elements can have conductivity variable from insulating dielectric to metallic. The materials have a wide range of applications as protective coatings and as electrically active materials. Metallic nanocomposites can exhibit superconductivity at low temperatures.

Abstract: A method for applying a metal film barrier layer between a substrate and a superconductor coating or over a superconductivity coating using chemical vapor deposition in which low vapor pressure reactants are used, is disclosed, which comprises the steps of providing a substrate and a quantity of metal-bearing reagent and one or more reagents, placing the substrate within the furnace, introducing the metal-bearing reagent by a powder feeder means and then the reagents at different times into and reacting them in the furnace, resulting in the deposition first of a coating of metal onto the substrate and then of a coating consisting essentially of the superconducting reactant components onto the metal film; said reagents generally chosen to yield the group of oxide superconductors.

Abstract: The present invention provides a method of manufacturing a high quality oxide superconductor film capable of controlling the film-forming rate and the film composition easily and forming the superconductor film safely and economically, over a wide region and homogeneously, wherein each of elements of R in which R represents one or more of elements selected from the group consisting of Y and lanthanide series rare earth elements, Ba and Cu is vapor deposited in the state of metal on a substrate under a high vacuum of lower than 10.sup.-8 Torr by a vacuum vapor deposition process to form a precursor comprising an amorphous metal and the precursor is oxidized and crystallized by applying a heat treatment without taking out the same into the atmospheric air.

Abstract: In a process for preparing a thin film of oxide superconductor having a layered crystal structure by depositing each layer of said layered crystal structure on a substrate by Molecular Beam Epitaxy (MBE) method with introducing oxygen-containing gas which is excited by irradiation of microwave, improvement in that a film-forming operation by the MBE method is interrupted temporarily after predetermined numbers of constituent layers which correspond to one unit crystal or less than one unit crystal are layered so that the deposited constituent layers are left in an activated oxygen atmosphere to effect a crystallization promotive operation, before the next film-forming operation is restarted.

Abstract: An article comprises an oriented thick film superconducting coating on a polycrystalline substrate. The coating includes at least two highly oriented platelet components ofBi.sub.a Sr.sub.b Ca.sub.c Cu.sub.d O.sub.x (BSCCO)wherein, in one component, a is 2, b is 2, c is 1, d is 2, and x is 8 and, in another component, a is 2, b is 2, c is 0, d is 1, and x is .apprxeq.6, oriented such that said BSCCO platelets are essentially parallel to said substrate. Suitable polycrystalline substrates are MgO and alumina and mullite.

Abstract: A superconducting Tl--Pb--Sr--Ca--Cu--O thin film comprised of at least one phase of the formula Tl.sub.0.5 Pb.sub.0.5 Sr.sub.2 Ca.sub.1+n Cu.sub.2+n O.sub.7+2n where n=0, 1 or 2 is disclosed, which is prepared by a process comprising sputtering an oxide film onto a dielectric substrate from an oxide target containing preselected amounts of Tl, Pb, Sr, Ca and Cu, and heating an oxygen-containing atmosphere in the deposited film in the presence of a source of thallium oxide and lead oxide and cooling the film.

Abstract: A method of preparing a superconductor. The method includes preparing a mixture of superconductor material constituents, disposing the constituents on a silver containing substrate, heating the mixture of constituents on a silver containing substrate, heating the mixture in a first atmosphere having a partial pressure of CO.sub.2 to control decomposition of at least one of the superconductor material constituents and changing the first atmosphere to a second atmosphere consisting essentially of an oxidizing gas capable of allowing decomposition of at least one of the superconductor material constituents.

Abstract: A method of forming a Bi system copper oxide superconducting thin film of Bi.sub.2 Sr.sub.2 Ca.sub.n-1 Cu.sub.n O.sub.x (n.gtoreq.2) including at least the equivalent of a pair of a full CuO molecular layer and a full CaO molecular layer, by a layer-by-layer process (an atomic layer piling process) using MBE. In accordance with the method, the CuO and CaO needed for the film are deposited in a pile by alternately depositing CuO in an amount equal to a 1/m portion of a full CuO molecular layer and CaO in an amount equal to a 1/ m portion of a full CaO molecular layer in a manner similar to that used for superlattice structure formation. The alternate deposition of CuO and CaO layer portions is repeated m times where m is an integral number of not less than n.

Abstract: A method of substantially aligning the superconducting grains of a multi-grained perovskite defect oxide type material, which material includes at least one superconducting phase. In the superconducting phase of such perovskite materials, the unit cells thereof include a plurality of substantially parallel metal oxide planes spacedly disposed along the c axis thereof. The aforementioned alignment of discrete grains of the multi-grained superconducting material occurs along the c axis.

Abstract: A laser ablation process for preparing an oxide superconducting thin film characterized in that an electrode is arranged between a substrate and a target. While the film is formed by laser ablation, a bias voltage of 75-100 V is applied between the electrode and the target.

Abstract: An oxide superconducting layer is formed on a base material of silver, whose single side is coated with MgO, or single-crystalline MgO for depositing a Bi.sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 phase in a crystallographically oriented state by sputtering, CVD or laser ablation. Metal lead or lead oxide is then laid thereon by sputtering to obtain a two-layer structure, and the two-layer structure is heat treated in the atmospheric air. Thus, a bismuth oxide superconducting film, which is excellent in crystal orientation as well as denseness and thereby having high critical current density, is formed on the base material.

Abstract: A strain tolerant multifilamentary wire capable of carrying superconducting currents is provided comprising a plurality of discontinuous filaments formed from a high temperature superconducting material. The discontinuous filaments have a length at least several orders of magnitude greater than the filament diameter and are sufficiently strong while in an amorphous state to withstand compaction. A normal metal is interposed between and binds the discontinuous filaments to form a normal metal matrix capable of withstanding heat treatment for converting the filaments to a superconducting state. The geometry of the filaments within the normal metal matrix provides substantial filament-to-filament overlap, and the normal metal is sufficiently thin to allow supercurrent transfer between the overlapped discontinuous filaments but is also sufficiently thick to provide strain relief to the filaments.

Abstract: A process for patterning layered thin films comprising a bottom oxide superconductor (1) layer deposited on a substrate (3) and another thin film (2) deposited on the bottom superconductor layer and consisting of insulator, ordinary conductor or oxide superconductor having a different crystal orientation from the bottom superconductor layer. The bottom superconductor layer (1) is subjecting to heat-treatment before another thin film (2) is deposited thereon. The heat-treatment can be carried out under a first condition in ultra high-vacuum at a temperature which is lower than the oxygen-trap temperature (T.sub.trap) at which oxygen can enter into the oxide superconductor but is higher than a temperature which is lower by 100.degree. C. than the oxygen-trap temperature (T.sub.trap -100.degree. C.) or under a second condition in an atmosphere containing oxygen of high purity at a temperature which is higher than the oxygen-trap temperature (T.sub.

Abstract: An article of manufacture having an epitaxial (111) magnesium oxide (MgO) layer, suitable for use as a buffer layer, on a (111) surface of a tetrahedral semiconductor substrate, and method for its manufacture is described. The article may further include an epitaxial oxide overlayer on the (111) MgO layer. The overlayer may be a conducting, superconducting, and/or ferroelectric oxide layer. The method of producing the epitaxial (111) magnesium oxide (MgO) layer on the (111) surface of a tetrahedral semiconductor substrate proceeds at low temperature. The method may further include steps for forming the epitaxial oxide layer on the (111) MgO layer. The methods include the steps of preparing the (111) surface of a tetrahedral semiconductor substrate for deposition and the low temperature depositing of an MgO layer on the prepared surface. Further steps may include the depositing of the oxide layer over the MgO layer.

Abstract: In situ vapor phase growth of thallium containing superconductors is achieved by controlling thallium volatility. Thallium volatility is controlled by providing active oxygen at the surface of the growing material and by avoiding collisions of energetic species with the growing material. In the preferred embodiment, a thallium containing superconductor is grown by laser ablation of a target, and by provision of oxygen during growth. More specifically, a source of thallium, calcium, barium, copper and oxygen is created by laser ablation of a thallium rich target, generating an ablation plume that is directed onto a heated substrate through the oxygen, with the plume passing through oxygen having a pressure from 10.sup.-2 to ten torr. Epitaxial superconducting thin films of thallium, calcium, barium, copper and oxygen have been grown by this technique. Various superconducting phases may be engineered through use of this method.

Abstract: A method for forming an oxide superconducting material by preparing first a shaped magnetic shield comprising an oxide superconductor as a matrix, and then effecting CVD and further EVD to fill in the pores of the matrix with an oxide superconductor; more specifically, it comprises introducing an oxidizing gas to said shaped magnetic shield from either inside or outside the shaped magnetic shield while introducing a material gas of said oxide superconductor from the other side thereof, and then maintaining said shaped magnetic shield at this state under a high temperature.

Abstract: A Josephson break junction device suitable for highly sensitive electronic detecting systems. A superconductor film such as YBa.sub.2 Cu.sub.3 O.sub.7 is deposited on a substrate such as a simple-crystal MgO. The film is fractured across a narrow strip by at least one indentation in the substrate juxtaposed from the strip to form a break junction. A transducer is affixed to the substrate for applying a bending movement to the substrate to regulate the distance across the gap formed at the fracture to produce a Josephson turned junction effect. Alternatively, or in addition to the transducer, a bridge of a novel metal is applied across the gap to produce a weak-link junction.

Abstract: An autogenous superconducting joint metallurgically bonding a pair of shaped superconducting pieces. Each of the pieces is formed by combining the metallic elements of a superconducting oxide in substantially the stoichiometric proportions needed to form the superconducting oxide, and then forming the combined metallic elements into a shaped piece. The microstructure of the joint is substantially the same as that of the portions of the pieces adjacent the joint.

Abstract: A superconducting transistor is provided with a base layer made of a normal conductor metal, an emitter layer made of a superconductor for injecting hot electrons to the base layer, a collector layer made of a superconductor for trapping electrons from the base layer, a first tunnel barrier layer made of an insulator and provided between the base layer and the emitter layer, and a second tunnel barrier layer made of an insulator and provided between the base layer and the collector layer.

Abstract: A substantially single phase, single crystalline, highly epitaxial film of Bi.sub.2 CaSr.sub.2 Cu.sub.2 O.sub.8 superconductor which has a T.sub.c (zero resistance) of 83 K is provided on a lattice-matched substrate with no intergrowth. This film is produced by a Liquid Phase Epitaxy method which includes the steps of forming a dilute supercooled molten solution of a single phase superconducting mixture of oxides of Bi, Ca, Sr, and Cu having an atomic ratio of about 2:1:2:2 in a nonreactive flux such as KCl, introducing the substrate, e.g., NdGaO.sub.3, into the molten solution at 850.degree. C., cooling the solution from 850.degree. C. to 830.degree. C. to grow the film and rapidly cooling the substrate to room temperature to maintain the desired single phase, single crystalline film structure.

Abstract: A CVD process for forming a layer or layers of superconducting materials on a semiconductor substrate in which volatile organometallic compounds of bismuth, strontium, calcium and copper are heated in the presence of a carrier gas in a first chamber free of hydrolyzing agents. Under conditions free of hydrolyzing agents, the carrier gas transports a predetermined quantity of the volatile organometallic compounds of the bismuth, strontium, calcium and copper to a deposition chamber. The compounds are decomposed and deposit mixed oxides on the substrate. Subsequent to deposition of the mixed oxides of the desired elements the layer is sintered in an oxygen-rich atmosphere, and formed into a superconducting film by subsequent slow cooling still in an oxygen-rich atmosphere.

Abstract: A process of making high temperature Tl-based superconductors. The process includes the steps of reacting solid Ba--Ca--Cu-oxides with Tl.sub.2 O.sub.3 vapor. The process allows high quality Tl-based superconductors to be easily fabricated.

Abstract: A process for preparing a thin film of oxide superconductor on a single crystal substrate of semiconductor by RF sputtering. At first, an under-layer of an oxide having a thickness of 50 to 200 .ANG. is deposited on the single crystal substrate of semiconductor at a substrate temperature of lower than 500.degree. C., and secondly an upper-layer of superconducting oxide material is deposited on said under-layer at a substrate temperature of higher than 600.degree. C.

Abstract: Process for increasing the density and improving the homogeneity of Chevrel phase powders and Chevrel phase wire obtained using said process. Chevrel phase powers are compounds of lead, mobydenum, and sulfur. Metallic additives in the range of 0.5% to 20% by weight are introduced in the Chevrel phase powders by a physical or chemical process. The melting temperature of the metallic additives is lower than the synthesis temperature of the Chevrel phase powders so as to increase the homogeneity. The wires obtained using this process are capable of generating high magnetic fields.

Abstract: According to the present invention, when a superconductive thin film is formed on a substrate of a single crystal, a compound having a composition of SrNdGaO.sub.4 and a K.sub.2 NiF.sub.4 type crystal structure is used as a material employable for the substrate. Alternatively, a single crystal composed of an oxide in which Ca, La and Cr are added to the foregoing compound is used as a material employable for the substrate. Then, a superconductive thin film composed of an oxide is formed on the substrate by employing an epitaxial growing method. Thus, the present invention makes it possible to provide a superconductive material having an excellent property of lattice alignment, a stable and high critical superconductivity temperature and a stable critical superconductivity electric current.

Abstract: In an oxide superconducting film wiring, when the line width is reduced, the evaporation of a component during firing becomes so vigorous that it becomes impossible to form a desired single crystal phase, which causes a significant lowering in the properties of the oxide superconducting wiring. This problem can be solved by preventing the evaporation of the evaporable component during the firing. Examples of this include a process wherein plate is placed above the superconductor forming material film wiring pattern on the substrate so as to face each other, the plate comprising a material having no chemical influence on the superconducting wiring, and a pattern of a material containing an evaporable component is arbitrarily formed, a process wherein a pattern having a smaller line width is sandwiched between patterns having a larger line width, and a process wherein the firing atmosphere or the concentration of the evaporable component in the pattern is varied depending upon the line width.

Abstract: A method of fabricating a superconductive flexible conductor having a high critical temperature in which method a deposit of superconductive ceramic is applied to a metal tape of thickness lying in the range 0.1 mm to 1 mm, wherein:the deposit of thickness lying in the range 50 .mu.m to 300 .mu.m and of concentration by volume of not less than 70% runs through an infrared beam at a speed of not less than 5 cm per minute, the zone treated by the the beam having a width of less than 10 mm relative to the travel direction and a surface temperature of not less than 1200.degree. C., thereby imparting a surface superconductive layer to the deposit which is of concentration by volume close to 100%, which is textured in the travel direction, and which is of thickness lying in the range 10 .mu.m to 100 .mu.m; andannealing is then performed under oxygen.

Abstract: A method for manufacturing a high Tc superconducting circuit elements is disclosed, which comprises the steps of preparing a single crystal conductive substrate of Sr.sub.2 RuO.sub.4 by a floating zone melting process; epitaxially growing on the (001)-surface of the Sr.sub.2 RuO.sub.4 substrate a high Tc copper oxide-based superconducting film with a thickness of 1 to 1000 nm; depositing metal pads onto said superconducting film to form electrical contacts; and applying a metal pad to the surface of the substrate to form an electrical contact.

Abstract: The present invention relates to an oxide superconductor comprising a composite oxide of RE , Ba and Cu, wherein the superconductor comprises a micro structure comprised of a monocrystalline REBa.sub.2 Cu.sub.3 O.sub.7-x phase (123 phase) and a RE.sub.2 BaCuO.sub.5 phase (211 phase) finely dispersed therein, the 123 phase being formed in a plurality of domains respectively for individual RE compositions and in the order of the 123 phase forming temperatures in respective layers.

Abstract: A method is disclosed to increase the critical transition temperature of superconducting materials by the selective application of stress to specific crystal directions. It has been found that by applying tensile stresses in certain directions and compressive stresses in other directions that the critical temperature of superconducting materials can be substantially increased.

Abstract: A method of forming thallium, barium, calcium, copper oxide films with smooth surfaces and chemical uniformity by sequentially depositing layers and annealing in the absence of a separate source of Tl.

Abstract: A process for producing a Bi-based perovskite superconducting film, comprising the steps of forming on a substrate a Pb-film, containing Bi-base material film comprising Bi, Pb, Sr, Ca and Cu in a Bi:Pb:Sr:Ca:Cu molar ratio of (1.9 to 2.1):(1.2 to 2.2, preferably 1.5 to 1.8):2:(1.9 to 2.2):(3 to 3.5) and sintering the Pb-containing Bi-base material film in an oxygen-containing atmosphere. The sintering step includes a main sintering period of 20 to 120 minutes, in which the temperature is raised from a first temperature to a second temperature, with the second temperature being in a range of 850.degree. to 860.degree. C., and the temperature rise in the main sintering period of 20 to 120 minutes being from 3.degree. to 10.degree. C.

Abstract: A method of manufacturing a DC superconducting quantum interference device comprises forming an insulating film over a portion of a resistance film. A lower electrode superconducting film is formed over the resistance film and the insulating film. A barrier layer is formed on a portion of the lower electrode superconducting film. An upper electrode is formed sandwiching the barrier layer between the lower electrode superconducting film and the upper electrode, so as to form a Josephson junction. To reduce the number of manufacturing steps, the lower electrode superconducting film is photolithographically patterned and/or etched to simultaneously form an input coil, a feedback coil and the Josephson junction. In another embodiment, after forming the upper electrode, an insulating film is formed over at least a portion of the lower electrode superconducting film. A superconducting film is formed over the insulating film in contact with the upper electrode.

Abstract: Improved processes for making thin film and bulk thallium superconductors are described, as well as Tl superconductors having high critical current densities and low surface impedance. An annealing step in a reduced oxygen atmosphere is used to convert compounds containing thallium, calcium, barium and copper to a Tl-2223 superconducting phase or to convert an oxide having the nominal composition Tl.sub.2 Ca.sub.2 Ba.sub.2 Cu.sub.3 O.sub.x to a crystalline Tl-2223 phase. The oxygen pressure during annealing is controlled to be below the thermodynamic stability limit for conversion of Tl-2223 to Tl-2122 and secondary phases. Temperatures less than 880.degree. C. are used, the oxygen pressure being sufficient to prevent excess thallium loss so that the Tl content in the final Tl-2223 phase is Tl.sub.1.6-2.0. Electrical devices including SQUIDs can be made with these improved superconductors.

Abstract: A process for producing a superconductor of an oxide system, which comprises uniformly mixing metal elements for constituting the oxide system at least partly in the form of alkoxides having CN.sup.--, X.sup.-- wherein A is a halogen atom and/or an amine, with the rest, if any, being in the form of acetylacetonates, carboxylates and/or water-soluble inorganic compounds to obtain a homogeneous mixture, and sintering the mixture.

Abstract: A beam (e.g. a focused laser beam) is utilized to irradiate the entire lateral width of a limited-extent portion of an elongated superconducting thin-film lead. The irradiated portion is converted to be non-superconducting and photoconductive. The converted portion constitutes a photodetector integrated with associated superconducting leads.

Abstract: A process for etching with a scanning tunneling microscope on both a single crystal and a thin film of high temperature superconductor is disclosed.

Abstract: Epitaxial heterojunctions formed between high temperature superconductors and metallic or semiconducting oxide barrier layers are provided. Metallic perovskites such as LaTiO.sub.3, CaVO.sub.3, and SrVO.sub.3 are grown on electron-type high temperature superconductors such as Nd.sub.1.85 Ce.sub.0.15 CuO.sub.4-x. Alternatively, transition metal bronzes of the form A.sub.x MO.sub.3 are epitaxially grown on electron-type high temperature superconductors. Also, semiconducting oxides of perovskite-related crystal structures such as WO.sub.3 are grown on either hole-type or electron-type high temperature superconductors.

Abstract: A method of forming a Bi-Sr-Ca-Cu-O system (Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.x) superconducting thin film in which two half-unit cells constitute a Perovskite structure layer, characterized in that Sr and Bi layers, which are present between said half-unit cells, are each deposited without oxidation by using an MBE process or an MO-MBE process with an atomic layer level control capability. A critical current density of the Bi-Sr-Ca-Cu-O system superconducting thin film is not significantly reduced.

Abstract: In order to enable formation of a smooth and dense oxide superconducting film with no clear appearance of grain boundaries in a fine structure even at a high film forming rate, a laser ablation method is employed to apply a laser beam 2 to a target 1 containing components of an oxide superconductive material and deposit particles, which are thus scattered from the target 1, on a substrate 3, while gaseous oxygen is supplied from a gaseous oxygen inlet 7 toward laser plume 6, which is generated by the application of the laser beam 2, and to a portion of the target irradiated with said laser.

Abstract: The present invention provides a methodology for forming an electrically conductive contact on the external surface of superconductive materials. The methodology is employed using any Noble metal to form the conductive contact; and is used with any superconductive material conventionally known. The resulting conductive contact provides a low electrical resistance and firm point of electrical junction for the superconductor with any conductive material in any electrical circuit or use.

Abstract: Films of high T.sub.c Bi-Sr-Ca-Cu-O superconductor have been prepared by MOCVD using volatile metal organic precursors and water vapor. The metal organic precursors are volatized along with a bismuth source, such as Bi(C.sub.6 H.sub.5).sub.3, deposited on a heated substrate to form a film, and annealed.

Abstract: A compound oxide superconductor represented by the general formula:Bi.sub.4+d (Sr.sub.1-x, Ca.sub.x).sub.m Cu.sub.n O.sub.p+yin which,"d" is an amount of excess bismuth and satisfies a range of 0<d.ltoreq.1.2,"m" is a number which satisfies a range of 6.ltoreq.m.ltoreq.10,"n" is a number which satisfies a range of 4.ltoreq.n.ltoreq.8,"p"=6+m+n,"x" is a number which satisfies a range of 0<x<1, and"y" is a number which satisfies a range of -2.ltoreq.<y.ltoreq.+2.A preferred example is a compound oxide system having the following general formula:Bi.sub.4+d Sr.sub.4 Ca.sub.4 Cu.sub.6 O.sub.20+yin which "d" is a number which satisfies the range 0.4.ltoreq.d.ltoreq.1.2 and "y" is a number which satisfies a range of -2.ltoreq.y.ltoreq.+2. The critical current density (J.sub.c) is improved by increasing the amount of bismuth with respect to the stoichiometric amount. A superconducting thin film is deposited on a substrate by physical vapor deposition such as sputtering.

Abstract: An epitaxial structure comprising a silicon containing substrate and a high T.sub.c copper-oxide-based superconducting layer, which may include an intermediate layer between the silicon substrate and the superconductor layer. Epitaxial deposition is accomplished by depositing a superconductor on a (001) surface of silicon in a manner in which the unit cell of the superconductor layer has two out of three of its crystallographic axes rotated 45 degrees with respect to the corresponding axes of the silicon unit cell, the remaining axis of the superconductor unit cell being normal to the Si (001) surface.

Abstract: Fine and homogeneous oxide particles for superconductors which can be sintered at a low temperature are prepared in a liquid phase by the sol-gel method using alkoxides as starting materials. By forming a buffer layer between a substrate and a superconducting film, good-quality and oriented superconducting film can be fabricated. Highly c-axis-oriented superconducting film and bulk products can be prepared from particular starting compositions in Ln-Ae-Cu-O and Bi-Ae-Cu-O systems. The oriented film can be produced by painting a paste of such starting compositions on a substrate followed by sintering, and the bulk form can be produced by pressing the pre-sintered powder of such starting compositions.

Abstract: A method for producing a structured layer of a first material having at least one recess of a predetermined geometrical shape on a substructure formed of at least one second material that includes a metal oxide superconductor material with a high transition temperature which is sensitive to solvents containing acids includes the steps of: forming a first composite by applying a varnish layer to the substructure which is soluble in a first solvent that does not attack the substructure such that the varnish layer has a structure corresponding to the structure of the structured layer of the first material to be produced; cold depositing on the first composite an auxiliary layer of a third material that is soluble in a second solvent which does not attack the first and second materials; forming a second composite from the first composite by removing with the first solvent the varnish layer along with a part of the auxiliary layer resting thereon; applying a coating layer of the first material to the second compos

Abstract: Improvement in a process for fabricating a superconducting junction by depositing successively a first oxide superconductor thin layer, a non-superconducting intermediate thin film layer and a second oxide superconductor thin film layer on a substrate in this order.In the invention, the non-superconducting intermediate thin film layer is composed of MgO and the substrate is preheated at 600.degree.-650.degree. C. for at least 5 minutes in the presence of O.sub.2, and is heated at a temperature between 200.degree. and 400.degree. C. during the non-superconducting intermediate thin film layer is deposited.