Abstract: In a Field Effect Transistor (FET) with a semiconductor channel the use of a high Tc oxide superconductor material in the gate electrode provides both control of parasitic resistance and capacitance and a proper work function when operated at a temperature below the Tc. The 1-2-3 compound oxide superconductors with the general formula Y1Ba2Cu3O7-y where y is approximately 0.1 have the ability in use in FET's to provide convenient work functions, low resistance and capacitance, and to withstand temperatures encountered in processing as the FET is being manufactured.

Abstract: A superconducting device has a substrate, and a superconducting channel provided by an oxide superconductor thin film formed to have an angle with respect to a deposition surface of the substrate. A superconductor source electrode region and a superconductor drain electrode region are formed at opposite ends of the superconducting channel, so that a superconducting current can flow through the superconducting channel between the superconductor source electrode region and the superconductor drain electrode region. A gate electrode region is formed of a oxide superconductor thin film which is deposited in parallel to the deposition surface of the substrate and which has an end portion which abuts with an insulating layer which separates the end portion and the superconducting channel so as to control superconducting current flow through the superconducting channel.

Abstract: An orientative ferroelectric thin film has such a structure that an epitaxial or orientative buffer layer having a double layer structure constituted by two layers is formed on a semiconductor single crystal (100) substrate, and an epitaxial or orientative perovskite ABO.sub.3 type ferroelectric thin film is further formed on the buffer layer. The epitaxial or orientative buffer layer has a structure in which a perovskite ABO.sub.3 type thin film is formed on an MgO thin film. Also, an orientative ferroelectric thin film has such a structure that an opitaxial MgO buffer layer is formed on a single crystal Si (100) substrate, and an epitaxial or orientative perovskite ABO.sub.3 type ferroelectric thin film is formed on the buffer layer.

Abstract: A field-effect structure formed on a substrate and comprising a channel with source and drain as well as a gate that is separated from the channel by an insulating layer. The channel is made of a high T.sub.c metal-oxide superconductor, e.g., YBaCuO, having a carrier density of about 10.sup.21 /cm.sup.3 and a correlation length of about 0.2 nm. The channel thickness is preferrable in the order of 1 nm. The superconductor is preferably a single crystalline and oriented such that the superconducting behavior is strongest in the plane parallel to the substrate. With a signal of a few volts applied to the gate, the entire channel cross-section is depleted of charge carriers whereby the channel resistance can be switched between a "zero resistance" (undepleted, superconducting) state and "very high resistance" (depleted state).

Abstract: A Josephson break junction device suitable for highly sensitive electronic detecting systems. A superconductor film such as YBa.sub.2 Al.sub.3 O.sub.7 is deposited on a substrate such as a single-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 nobel metal is applied across the gap to produce a weak-link junction.

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: A superconducting tunnel junction radiation sensing device includes first and second superconductor electrodes and a tunnel barrier layer interposed therebetween. The tunnel barrier layer is made up of a thin-wall portion and a thick-wall portion each formed of a semiconductor or an insulator, and each having opposite surfaces respectively contacting the first and second superconductor electrodes, and each extending adjacent each other in a same horizontal plane between the first and second electrodes. The thick-wall portion has a vertical thickness which is at least twice that of the thin-wall portion. Furthermore, the thickness of the thin-wall portion is such that a tunnel effect is enabled therethrough form the first electrode to the second electrode, and the thickness of the thick-wall portion is such that a tunnel effect is substantially prohibited therethrough from the first electrode to the second electrode.

Abstract: A Josephson device, comprising a junction formed by forming the first layer-shaped oxide superconductor thin film including a plurality of Cu-O layers on a substrate, a barrier layer thereon and the second layer-shaped oxide superconductor thin film on the barrier layer. The Josephson device according to the present invention is manufactured by forming the first layer-shaped oxide superconductor thin film on a substrate, forming a barrier layer in the same vacuum chamber, defining patterns to said barrier layer and said first layer-shaped oxide superconductor thin film, forming an interlayer insulating film on said barrier layer, removing said interlayer insulating film in a region serving as a junction, effecting exposure to oxygen plasma, forming the second layer-shaped oxide superconductor thin film in contact with a part of the surface of said barrier layer and defining patterns to said second layer-shaped oxide superconductor thin film.

Abstract: Integrated electronic assemblies according to the invention, typically semiconductor IC chips, comprise an air gap transmission line. The line has high propagation speed and low dispersion, and can be readily manufactured. Various embodiments of the inventive transmission line are disclosed. In all cases the semiconductor substrate is etched so as to remove at least a substantial portion of the semiconductor material under and/or adjacent to the conductor line or lines. Insulator material (e.g., SiO.sub.2) serves, inter alia, to support the conductor.