Abstract: NRAM arrays with nanotube blocks, traces and planes, and methods of making the same are disclosed. In some embodiments, a nanotube memory array includes a nanotube fabric layer disposed in electrical communication with first and second conductor layers. A memory operation circuit including a circuit for generating and applying a select signal on first and second conductor layers to induce a change in the resistance of the nanotube fabric layer between the first and second conductor layers is provided. At least two adjacent memory cells are formed in at least two selected cross sections of the nanotube fabric and conductor layers such that each memory cell is uniquely addressable and programmable. For each cell, a change in resistance corresponds to a change in an informational state of the memory cell. Some embodiments include bit lines, word lines, and reference lines. In some embodiments, 6F2 memory cell density is achieved.

Abstract: Methods and systems of using nanotube elements as joule heating elements for memories and other applications. Under one aspect, a method includes providing an electrical stimulus, regulated by a drive circuit, through a nanotube element in order to heat an adjacent article. Further, a detection circuit electrically gauges the state of the article. The article heated by the nanotube element is, in preferred embodiments, a phase changing material, hi memory applications, the invention may be used as a small-scale CRAM capable of employing small amounts of current to induce rapid, large temperature changes in a chalcogenide material. Under various embodiments of the disclosed invention, the nanotube element is composed of a non-woven nanotube fabric which is either suspended from supports and positioned adjacent to the phase change material or is disposed on a substrate and in direct contact with the phase change material.

Abstract: Under one aspect, a non-volatile nanotube diode device includes first and second terminals; a semiconductor element including a cathode and an anode, and capable of forming a conductive pathway between the cathode and anode in response to electrical stimulus applied to the first conductive terminal; and a nanotube switching element including a nanotube fabric article in electrical communication with the semiconductive element, the nanotube fabric article disposed between and capable of forming a conductive pathway between the semiconductor element and the second terminal, wherein electrical stimuli on the first and second terminals causes a plurality of logic states.

Abstract: Light emitters using nanotubes and methods of making same. A light emitter includes a nanotube article in electrical communication with a first and a second contact, a substrate having a predefined region with a relatively low thermal conductivity said region in predefined physical relation to said nanotube article; and a stimulus circuit in electrical communication with the first and second contacts. The stimulus circuit provides electrical stimulation sufficient to induce light emission from the nanotube article in the proximity of the predefined region. The predefined region is a channel formed in the substrate or a region of material with relatively low thermal conductivity. The light emitter can be integrated with semiconductor circuits including CMOS circuits. The light emitter can be integrated into optical driver circuits (on- and off-chip drivers) and opto-isolators.

Abstract: Embodiments of the present invention provide methods for fabricating graphene nanoelectronic devices with semiconductor compatible processes, which allow wafer scale fabrication of graphene nanoelectronic devices. Embodiments of the present invention also provide methods for passivating graphene nanoelectronic devices, which enable stacking of multiple graphene devices and the creation of high density graphene based circuits. Other embodiments provide methods for producing devices with graphene layer segments having multiple thicknesses.

Abstract: An example of a carbon nanotube capacitor may include (i) a carbon nanotube film having carbon nanotubes and voids with dielectric material, (ii) conductive contacts and (iii) a dielectric layer. The carbon nanotube film may switch from a conductive state to a non-conductive state when a voltage is applied by creating an electrical break within the carbon nanotube film and providing a first conductive region and a second conductive region within the carbon nanotube film. The electrical break may separate the first conductive region from the second conductive region. The first and second conductive regions may store charge. An integrated device may include one or more transistors and one or more carbon nanotube capacitors. A method of making a carbon nanotube capacitor is also disclosed.

Abstract: Carbon Nanotube Films, Layers, Fabrics, Ribbons, Elements and Articles are disclosed. To make various articles, certain embodiments provide a substrate. Preformed nanotubes are applied to a surface of the substrate to create a non-woven fabric of carbon nanotubes. Portions of the non-woven fabric are selectively removed according to a defined pattern to create the article. To make a nanofabric, a substrate is provided. Preformed nanotubes are applied to a surface of the substrate to create a non-woven fabric of carbon nanotubes wherein the non-woven fabric is substantially uniform density. The nanofabrics and articles have characteristics desirable for various electrical systems such as memory circuits and conductive traces and pads.

Abstract: Under one aspect, a system (100) for sensing the presense of an analyte in a fluid includes a nanotube sensor element including a plurality of nanotubes and positioned for exposure to a fluid; an optical source capable of generating optical radiation (102), the radiation having a source frequency and a fluence selected to generate a nonlinear optical response by the nanotube sensor element; an optical detector (110) capable of measuring the nonlinear optical response by the nanotube sensor element; and logic in electrical communications with the optical detector to sense the presense of an analyte in the fluid based on the nonlinear optical response measured by the optical detector.

Abstract: A two terminal switching device includes a first conductive terminal, a second conductive terminal in spaced relation to the first terminal, the first terminal encompassed by the second terminal. The device also includes an electrically insulating spacer that encompasses the first terminal and provides the spaced relation between the second terminal and the first terminal. It also includes a nanotube article comprising at least one carbon nanotube, the nanotube article being arranged to overlap at least a portion of each of the first and second terminals. The device also includes a stimulus circuit in electrical communication with at least one of the first and second terminals that is capable of applying a first electrical stimulus to at least one of the first and second terminals to change the resistance of the device between the first and second terminals from a relatively low resistance to a relatively high resistance.

Abstract: Under one aspect, a non-volatile nanotube switch includes a first terminal; a nanotube block including a multilayer nanotube fabric, at least a portion of which is positioned over and in contact with at least a portion of the first terminal; a second terminal, at least a portion of which is positioned over and in contact with at least a portion of the nanotube block, wherein the nanotube block is constructed and arranged to prevent direct physical and electrical contact between the first and second terminals; and control circuitry capable of applying electrical stimulus to the first and second terminals. The nanotube block can switch between a plurality of electronic states in response to a plurality of electrical stimuli applied by the control circuitry to the first and second terminals. For each different electronic state, the nanotube block provides an electrical pathway of different resistance between the first and second terminals.

Abstract: Nanotube switching devices having nanotube bridges are disclosed. Two-terminal nanotube switches include conductive terminals extending up from a substrate and defining a void in the substrate. Nantoube articles are suspended over the void or form a bottom surface of a void. The nanotube articles are arranged to permanently contact at least a portion of the conductive terminals. An electrical stimulus circuit in communication with the conductive terminals is used to generate and apply selected waveforms to induce a change in resistance of the device between relatively high and low resistance values. Relatively high and relatively low resistance values correspond to states of the device. A single conductive terminal and a interconnect line may be used. The nanotube article may comprise a patterned region of nanotube fabric, having an active region with a relatively high or relatively low resistance value. Methods of making each device are disclosed.

Abstract: A nanotube random access memory (NRAM) structure is provided. The structure includes a substrate, a gate electrode disposed in the substrate, and a first nanotube fabric disposed on the substrate. The first nanotube fabric has a channel region spaced apart from the gate electrode by a portion of the substrate. The structure also includes a drain contact contacting the first nanotube fabric. The structure also includes a second nanotube fabric disposed on the substrate, and is adjacent and connected to the first nanotube fabric. The structure also includes a source contact contacting the second nanotube fabric. The first nanotube fabric is a high-voltage fabric compared to the second nanotube fabric such that when a voltage is applied across the first nanotube fabric and the second nanotube fabric via the drain contact and the source contact, the second nanotube fabric is permitted to switch without switching the first nanotube fabric.

Abstract: Vacuum microelectronic devices with carbon nanotube films, layers, ribbons and fabrics are provided. The present invention discloses microelectronic vacuum devices including triode structures that include three-terminals (an emitter, a grid and an anode), and also higher-order devices such as tetrodes and pentodes, all of which use carbon nanotubes to form various components of the devices. In certain embodiments, patterned portions of nanotube fabric may be used as grid/gate components, conductive traces, etc. Nanotube fabrics may be suspended or conformally disposed. In certain embodiments, methods for stiffening a nanotube fabric layer are used. Various methods for applying, selectively removing (e.g. etching), suspending, and stiffening vertically- and horizontally-disposed nanotube fabrics are disclosed, as are CMOS-compatible fabrication methods. In certain embodiments, nanotube fabric triodes provide high-speed, small-scale, low-power devices that can be employed in radiation-intensive applications.

Abstract: Electromagnetic radiation detecting and sensing systems using carbon nanotube fabrics and methods of making the same are provided. In certain embodiments of the invention, an electromagnetic radiation detector includes a substrate, a nanotube fabric disposed on the substrate, the nanotube fabric comprising a non-woven network of nanotubes, and first and second conductive terminals, each in electrical communication with the nanotube fabric, the first and second conductive terminals disposed in space relation to one another. Nanotube fabrics may be tuned to be sensitive to a predetermined range of electromagnetic radiation such that exposure to the electromagnetic radiation induces a change in impedance between the first and second conductive terminals. The detectors include microbolometers, themistors and resistive thermal sensors, each constructed with nanotube fabric. Nanotube fabric detector arrays may be formed for broad-range electromagnetic radiation detecting.

Abstract: A non-volatile resistive memory is provided. The memory includes at least one non-volatile memory cell and selection circuitry. Each memory cell has a two-terminal nanotube switching device having and a nanotube fabric article disposed between and in electrical communication with two conductive terminals. Selection circuitry is operable to select the two-terminal nanotube switching device for read and write operations. Write control circuitry, responsive to a control signal, supplies write signals to a selected memory cell to induce a change in the resistance of the nanotube fabric article, the resistance corresponding to an informational state of the memory cell. Resistance sensing circuitry in communication with a selected nonvolatile memory cell, senses the resistance of the nanotube fabric article and provides the control signal to the write control circuitry. Read circuitry reads the corresponding informational state of the memory cell.

Abstract: Manufacturers encounter limitations in forming low resistance ohmic electrical contact to semiconductor material P-type Gallium Nitride (p-GaN), commonly used in photonic applications, such that the contact is highly transparent to the light emission of the device. Carbon nanotubes (CNTs) can address this problem due to their combined metallic and semiconducting characteristics in conjunction with the fact that a fabric of CNTs has high optical transparency. The physical structure of the contact scheme is broken down into three components, a) the GaN, b) an interface material and c) the metallic conductor. The role of the interface material is to make suitable contact to both the GaN and the metal so that the GaN, in turn, will make good electrical contact to the metallic conductor that interfaces the device to external circuitry. A method of fabricating contact to GaN using CNTs and metal while maintaining protection of the GaN surface is provided.

Abstract: Under one aspect, a nonvolatile nanotube diode includes: a substrate; a semiconductor element disposed over the substrate, the semiconductor element having an anode and a cathode and capable of forming an electrically conductive pathway between the anode and the cathode; a nanotube switching element disposed over the semiconductor element, the nanotube switching element including a conductive contact and a nanotube fabric element capable of a plurality of resistance states; and a conductive terminal disposed in spaced relation to the conductive contact, wherein the nanotube fabric element is interposed between and in electrical communication with the conductive contact and the conductive contact is in electrical communication with the cathode, and wherein in response to electrical stimuli applied to the anode and the conductive terminal, the nonvolatile nanotube diode is capable of forming an electrically conductive pathway between the anode and the conductive terminal.

Abstract: Under one aspect, a method of cooling a circuit element includes providing a thermal reservoir having a temperature lower than an operating temperature of the circuit element; and providing a nanotube article in thermal contact with the circuit element and with the reservoir, the nanotube article including a non-woven fabric of nanotubes in contact with other nanotubes to define a plurality of thermal pathways along the article, the nanotube article having a nanotube density and a shape selected such that the nanotube article is capable of transferring heat from the circuit element to the thermal reservoir.

Abstract: A non-volatile latch circuit is provided. The non-volatile latch circuit includes a nanotube switching element capable of switching between resistance states and non-volatilely retaining the resistance state. The non-volatile latch circuit includes a volatile latch circuit is capable of receiving and volatilely storing a logic state. When the nanotube switching element is a resistance state, the volatile latch circuit retains a corresponding logic state and outputs that corresponding logic state at an output terminal. A non-volatile register file configuration circuit for use with a plurality of non-volatile register files is also provided. The non-volatile register file configuration circuit includes a selection circuitry and a plurality of nanotube fuse elements, each in electrical communication with one of a plurality of non-volatile register files.

Abstract: Under one aspect, a resonator 400 includes a nanotube element 410 including a non-woven fabric of unaligned nanotubes and having a thickness, and a support structure 404 defining a gap 406 over which the nanotube element 410 is suspended, the thickness of the nanotube element 410 and the length of the gap 406 being selected to provide a pre-specified resonance frequency for the resonator 400 The resonator 400 also includes a conductive element 412 in electrical contact with the nanotube element 410, a drive electrode 408 in spaced relation to the nanotube element 410, and power logic in electrical contact with die at least one drive electrode 408 The power logic provides a series of electrical pulses at a frequency selected to be about the same as the pre-specified resonance frequency of the resonator 400 to the drive electrode 408 during operation of the resonator 400, such that the nanotube element 410 responds to the series of electrical pulses applied to the drive electrode 408 by making a series of mecha