摘要:
Magnetoelectric spin-orbit logic (MESO) devices comprise a magnetoelectric switch capacitor coupled to a spin-orbit coupling structure. The logic state of the MESO device is represented by the magnetization orientation of the ferromagnet of the magnetoelectric switch capacitor and the spin-orbit coupling structure converts the magnetization orientation of the ferromagnet to an output current. MESO devices in which all or at least some of the constituent layers of the device are perovskite materials can provide advantages such as improved control over the manufacturing of MESO devices and high quality interfaces between MESO layers due to the lattice matching of perovskite materials.
摘要:
Technologies for a transistor with a ferroelectric gate dielectric are disclosed. In the illustrative embodiment, a transistor has a ferroelectric gate dielectric that is lattice matched to the channel of the transistor. In one embodiment, the ferroelectric polarization changes when voltage is applied and removed from a gate electrode, facilitating switching of the transistor at a lower applied voltage. In another embodiment, the ferroelectric polarization of a gate dielectric of a transistor changes when the voltage is past a positive threshold value or a negative threshold value. Such a transistor can be used as a one transistor memory cell.
摘要:
A ferroelectric memory cell formed on a monocrystalline silicon underlayer, either an epitaxial silicon contact plug to a transistor source or drain or silicon gate region for which the memory cell forms a non-volatile gate. A conductive barrier layer of doped strontium titanate, whether cationically substituted, such by lanthanum or niobium for strontium and titanium respectively, or anionically deficient, is epitaxially grown over the silicon, and a lower metal oxide electrode layer, a ferroelectric layer and an upper metal oxide electrode layer are epitaxially grown on the barrier layer. No platinum barrier is needed beneath the ferroelectric stack. The invention can be applied to many other functional oxide materials of the Ruddlesden-Popper and devices including micromachined electromechanical (MEM) devices and ferromagnetic tri-layer devices.
摘要:
A media for storing information comprises a substrate, a conductive layer formed over the substrate, and a ferroelectric layer epitaxially formed on the conductive layer. The ferroelectric layer includes an a-lattice constant that is substantially matched to an a-lattice constant of the conductive layer and an average c-lattice constant that is longer than an average c-lattice constant of a bulk-grown ferroelectric layer.
摘要:
A circuit element that includes a ferroelectric device connected to a substrate device. The circuit element is constructed by fabricating the substrate device in a semiconductor substrate and depositing a dielectric layer over the semiconductor substrate. A via is then etched in the dielectric layer to provide access to the substrate device and filled with copper or tungsten. A layer of a conducting metallic oxide is then deposited on the conducting plug, and a layer of ferroelectric material is deposited on the layer of conducting metal oxide. The layer of conducting metallic oxide is deposited at a temperature below 450° C., preferably at room temperature.
摘要:
A ferroelectric cell, particularly one integrated on a silicon substrate, comprising an amorphous barrier layer interposed between the ferroelectric stack and the silicon. Preferably, the ferroelectric stack includes conductive metal oxide electrodes sandwiching the ferroelectric layer. The metal oxide may act as a templating layer to crystallographically orient the ferroelectric layer. Alternatively, the electrodes and ferroelectric layer may be polycrystalline. The amorphous barrier layer may be composed of an intermetallic alloy, such as Ti3Al, a metal-metalloid, such as Pd—Si, a combination of early and later transition metals, such as Ti—Ni, and other related compound metal systems, such as (Ti, Zr)—Be, that form amorphous metals.
摘要:
A ferroelectric memory cell integrated with silicon circuitry which require a forming-gas anneal of the silicon circuitry after the ferroelectric stack has been formed. The ferroelectric layer may have a composition such that there is no space in the lattice of the ferroelectric phase to accommodate atomic hydrogen or have a composition with a Curie temperature below the temperature of the forming-gas anneal. Preferably, there is no upper platinum electrode, or it is deposited after the forming-gas anneal. A metal-oxide upper electrode serves as barrier to the forming-gas anneal, and an intermetallic layer positioned above the ferroelectric stack serves as an even better barrier. Forming-gas damage to the ferroelectric stack can be removed by a recovery anneal in a hydrogen-free environment, preferably performed at a temperature above the Curie temperature.
摘要:
A functional perovskite cell formed on a silicon substrate layer and including a functional layer of bismuth ferrite (BiFeO3 or BFO) sandwiched between two electrode layers. An intermediate template layer, for example, of strontium titanate allows the bismuth ferrite layer to be crystallographically aligned with the silicon substrate layer. Other barrier layers of platinum or an intermetallic alloy produce a polycrystalline BFO layer. The cell may be configured as a non-volatile memory cell or a MEMS structure respectively depending upon the ferroelectric and piezoelectric character of BFO. The films may be grown by MOCVD using a heated vaporizer.
摘要翻译:形成在硅衬底层上并且包含夹在两个电极层之间的铋铁氧体(BiFeO 3 N 3或BFO)的功能层的功能性钙钛矿电池。 中间模板层例如钛酸锶允许铋铁氧体层与硅衬底层结晶地取向。 铂或金属间化合物的其它阻挡层产生多晶BFO层。 可以根据BFO的铁电和压电特性分别将单元配置为非易失性存储单元或MEMS结构。 可以使用加热蒸发器通过MOCVD生长膜。
摘要:
The present invention provides a spacer assembly which is tailored to provide a secondary electron emission coefficient of approximately 1 for the spacer assembly when the spacer assembly is subjected to flat panel display operating voltages. The present invention further provides a spacer assembly which accomplishes the above achievement and which does not degrade severely when subjected to electron bombardment. The present invention further provides a spacer assembly which accomplishes both of the above-listed achievements and which does not significantly contribute to contamination of the vacuum environment of the flat panel display or be susceptible to contamination that may evolve within the tube. Specifically, in one embodiment, the present invention is comprised of a spacer structure which has a specific secondary electron emission coefficient function associated therewith. The material comprising the spacer structure is tailored to provide a secondary electron emission coefficient of approximately 1 for the spacer assembly when the spacer assembly is subjected to flat panel display operating voltages.
摘要:
A ferroelectric capacitor structure and its method of making in which a ferroelectric stack of two metal-oxide electrodes sandwiching a ferroelectric layer is fabricated on a silicon substrate with an intervening barrier layer, preferably of TiN. In one embodiment, a platinum layer is grown between the TiN and the lower metal-oxide electrode at a sufficiently high temperature that provides crystallographically ordered growth of the ferroelectric stack. In another embodiment, the platinum layer was completely eliminated with the lower electrode being grown directly on the TiN. Although the conventional conductive metal-oxide used in the electrode is lanthanum strontium cobalt oxide (LSCO), lanthanum nickel oxide provides good electrical and lifetime characteristics in a ferroelectric cell. Alternatively, the electrodes can be formed of the rock-salt metal oxides, such as neodymium oxide (NdO).