摘要:
An antenna comprises an arrangement of electrically conducting segments, the arrangement including intersection points where two or more electrically conducting segments are in electrical communication. Example antennas include a plurality of capacitors located within some or all of the electrically conducting segments. Capacitance values can be determined using an optimization algorithm to obtain desired values of antenna resonance frequency (or frequencies), bandwidth, and/or radiation pattern, and may be adjusted in order to control an antenna parameter such as beam steering direction.
摘要:
A reconfigurable frequency selective surface (FSS) includes a plurality of conducting patches supported on the surface of a dielectric layer, with selectable electrical interconnections between the conducting patches so as to provide a desired characteristic. The reconfigurable FSS can be used in a reconfigurable artificial magnetic conductor (AMC). A reconfigurable AMC includes a dielectric layer, a conducting back-plane on one surface of the dielectric layer, and a reconfigurable FSS on the other surface of the dielectric layer. A reconfigurable AMC can be used as a dynamically reconfigurable ground plane for a low-profile antenna system.
摘要:
The method of the invention configures a tri-layer thin film transistor (TFT) on a substrate, the TFT including a stack including a gate electrode supported by the substrate, followed by a first layer of insulator, a layer of semiconductor and a second layer of insulator. The method employs a first step of illumination through the substrate, as shadowed by said gate electrode, to enable a patterning of the second layer of insulator into an insulator patch which is aligned with the gate electrode. A next step of illumination through the substrate, as shadowed by said gate electrode, enables a patterning of metallization contacts for the TFT in alignment with the insulator patch.
摘要:
A layer of an amphoteric dopant on the surface of a group III-V intermetallic semiconductor crystal will diffuse into the crystal surface in a heating cycle forming a stable contact. The contact can be ohmic or rectifying depending on the localized presence of an excess of one crystal ingredient. A layer of Si on GaAs upon heating forms a rectifying contact. When the layer of Si contains As, the contact is ohmic.
摘要:
A submicron conductor is formed by placing a metal member over an insulator both terminating at a common defined edge. An angularly deposited metal against the edge provides a broad metal conductor attached along the entire edge of a thin metal member which is positioned on the substrate on a narrow line with the width defined by the horizontal component of the angular deposition. A removal operation removes with respect to the vertical component of the angular deposition the excess angularly deposited metal and leaves a vertical, very narrow metal conductor having a horizontal metal over the dielectric in electrical and supporting contact along the entire length. The asymmetry of the conductor provides field effect transistor advantages.
摘要:
Disclosed herein is an aqueous alkaline etching solution comprising water and an alkaline material being selected from the group consisting of ammonium hydroxide, ammonium phosphate, ammonium carbonate, quaternary ammonium hydroxide, quaternary ammonium phosphate, quaternary ammonium carbonate, an alkali metal hydroxide, an alkaline earth metal hydroxide, or a combination comprising at least one of the foregoing alkaline materials; the aqueous alkaline solution being operative to etch aluminum oxide at a rate greater than or equal to about 2:1 over a rate at which it etches a metal oxide semiconductor to be protected; wherein the aqueous etching solution has a pH of 8 to 13.
摘要:
The present invention discloses plasma enhanced chemical vapor deposition (PECVD) process for depositing n-type and p-type zinc oxide-based transparent conducting oxides (TCOs) at low temperatures with excellent optical and electrical properties on glass and temperature sensitive materials such as plastics and polymers. Specifically, it discloses PECVD process for depositing n-type ZnO by doping it with B or F and p-type ZnO by doping it with nitrogen excellent optical and electrical properties on glass and temperature sensitive materials such as plastics and polymers for TCO application. The process utilizes a mixture of volatile zinc compound, argon and/or helium as a diluent gas, carbon dioxide as an oxidant, and a dopant or reactant to deposit the desired ZnO-based TCOs.
摘要:
Passive or active pixelized antenna structures are described in which the radio-frequency (RF) tuning of individual antenna pixel elements, the connections of individual antenna pixel elements to other antenna elements, and optionally the local phase of individual elements or groups of elements, is varied and controlled using tunable elements. Efficient and low-cost control of a large number of tunable elements is provided by matrix addressing techniques.
摘要:
An electrical device which employs two-dimensional space charge modulation in a semiconductor structure. The device has an approximately Debye length wide contact and a rectifying contact positioned adjacent to each other within a Debye length on a semiconductor body and a contact remotely positioned. A bias on the rectifying contact will effect conduction between the other contacts.
摘要:
Crystalline compound semiconductors are passivated with a layer of the most volatile element thereof to prevent the formation of oxides that would interfere with further processing. A GaAs crystal is provided with a surface layer of arsenic. The arsenic layer is formed by exposure to light having a photon energy greater than 1.8 eV, at a power density of 0.01 to 0.5 watts per cm.sup.2 while the GaAs immersed in a 1:1 HCl:H.sub.2 O solution for a period of 10-30 minutes. The intermediate processing passivated GaAs crystal may be stored and handled in air and the As layer is removed by low temperature baking.