An elementary cell includes a device and a non-volatile resistive memory mounted in a series, the device including an upper selector electrode, a lower selector electrode, a layer made up of a first active material, referred to as an active selecting layer, the device being intended to form a volatile selector; the memory including an upper memory electrode, a lower memory electrode, a layer made of at least a second active material, referred to as an active memory layer, the active selecting layer being in a conductive crystalline state and the memory being in a very strongly resistive state that is more resistive than the strongly resistive state of the memory.

Embodiments of contact structures of a three-dimensional memory device and fabrication method thereof are disclosed. The three-dimensional memory structure includes a film stack disposed on a substrate, wherein the film stack includes a plurality of conductive and dielectric layer pairs, each conductive and dielectric layer pair having a conductive layer and a first dielectric layer. The three-dimensional memory structure also includes a staircase structure formed in the film stack, wherein the staircase structure includes a plurality of steps, each staircase step having two or more conductive and dielectric layer pairs. The three-dimensional memory structure further includes a plurality of coaxial contact structures formed in a first insulating layer over the staircase structure, wherein each coaxial contact structure includes one or more conductive and insulating ring pairs and a conductive core, each conductive and insulating ring pair having a conductive ring and an insulating ring.

An oscillating element includes a substrate, negative resistance elements which are electrically connected to the substrate, antennas which are electrically connected one-to-one to each negative resistance element and which transmit or receive an electromagnetic wave, a pad electrically connected to a power supply source for supplying power to the antennas, and a conductor which electrically connects the pad and the antennas to each other. The conductor is constituted of a common wiring that is common to the antennas and individual wirings from the common wiring to each antenna. The individual wirings differ from each other with respect to a sectional area, resistivity, and a length in accordance with a position on the substrate of an antenna connected to each wiring to reduce a difference in wiring resistances caused based on a distance between the antenna connected to each wiring and the pad.

The present invention discloses a neuron and a neuromorphic system including the same. The neuron according to an embodiment of the present invention includes a metal insulator metal (MIM) device including a metal ion-doped insulating layer and configured to perform integration and fire, and the MIM device is formed to have a negative differential resistance (NDR) region in which current decreases as voltage increases.

A negative differential resistance (NDR) device for non-volatile memory cells in crossbar arrays is provided. Each non-volatile memory cell is situated at a crosspoint of the array. Each non-volatile memory cell comprises a switching layer in series with an NDR material containing fast diffusive atoms that are electrochemically inactive. The switching layer is positioned between two elec-trodes.

An oscillating element includes a substrate, negative resistance elements which are electrically connected to the substrate, antennas which are electrically connected one-to-one to each negative resistance element and which transmit or receive an electromagnetic wave, a pad electrically connected to a power supply source for supplying power to the antennas, and a conductor which electrically connects the pad and the antennas to each other. The conductor is constituted of a common wiring that is common to the antennas and individual wirings from the common wiring to each antenna. The individual wirings differ from each other with respect to a sectional area, resistivity, and a length in accordance with a position on the substrate of an antenna connected to each wiring to reduce a difference in wiring resistances caused based on a distance between the antenna connected to each wiring and the pad.

A vanadium dioxide (VO.sub.2)-based threshold switch device exhibiting current-controlled negative differential resistance (S-type NDR), an electrical oscillator circuit based on the threshold switch device, a wafer including a plurality of said devices, and a method of manufacturing said device are provided. The VO.sub.2-based threshold switch device exhibits volatile resistance switching and current-controlled negative differential resistance from the first time a sweeping voltage or voltage pulse is applied across the device without being treated with an electroforming process. Furthermore, the device exhibits substantially identical switching characteristics over at least 10.sup.3 switching operations between a high resistance state (HRS) and a low resistance state (LRS), and a plurality of threshold switch devices exhibits a threshold voltage V.sub.T spreading of less than about 25%. The threshold switch device may be included in an oscillator circuit to produce an astable oscillator that may serve as a functional building block in spiking-neuron based neuromorphic computing.

Provided is a multi-negative differential resistance device. The multi-negative differential resistance device includes a first negative differential resistance device and a second negative differential resistance device connected in parallel with the first negative differential resistance device, and a peak and a valley of the first negative differential resistance device and a peak and a valley of the second negative differential resistance device are synthesized, and, thus, the multi-negative differential resistance device has two peaks and two valleys.

The present invention features a microwave gain medium having a negative refractive index, which overcompensates for loss exhibited in conventional passive metamaterials. The design consists of sub-wavelength building blocks with embedded microwave tunnel diodes exhibiting a negative refractive index and a stable net gain. The negative resistance may also be used for dispersion compensation that may enable broadband response of metamaterials.

A vanadium dioxide (VO.sub.2)-based threshold switch device exhibiting current-controlled negative differential resistance (S-type NDR), an electrical oscillator circuit based on the threshold switch device, a wafer including a plurality of said devices, and a method of manufacturing said device are provided. The VO.sub.2-based threshold switch device exhibits volatile resistance switching and current-controlled negative differential resistance from the first time a sweeping voltage or voltage pulse is applied across the device without being treated with an electroforming process. Furthermore, the device exhibits substantially identical switching characteristics over at least 10.sup.3 switching operations between a high resistance state (HRS) and a low resistance state (LRS), and a plurality of threshold switch devices exhibits a threshold voltage V.sub.T spreading of less than about 25%. The threshold switch device may be included in an oscillator circuit to produce an astable oscillator that may serve as a functional building block in spiking-neuron based neuromorphic computing.