Nantero, Inc.

Lockheed Martin Corporation

Nanotero, Inc.

Mitchell Meinhold

Claude Louis Bertin

Thomas Rueckes

Steven L Konsek

Ramesh Sivarajan

X M Henry Huang

Jonathan Wesley Ward

Frank Guo

Eliodor G Ghenciu

Max Strasburg

Darren K Brock

Brent M Segal

Thomas Ruckes

Benjamin Schlatka

Colin D Yates

Robert F Smith

Christopher L Neville

Steven Konsek

Michael J O'Connor

X M H Huang

X M Huang

Xm Henry Huang

XM Henry Huang

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.

Nonvolatile nanotube switch elements using sidewall contacts

Double density nonvolatile nanotube switch memory cells

Stacked three-dimensional arrays of two terminal nanotube switching devices

Under one aspect, a method of making a nanotube switch includes: providing a substrate having a first conductive terminal; depositing a multilayer nanotube fabric over the first conductive terminal; and depositing a second conductive terminal over the multilayer nanotube fabric, the nanotube fabric having a thickness, density, and composition selected to prevent direct physical and electrical contact between the first and second conductive terminals. In some embodiments, the first and second conductive terminals and the multilayer nanotube fabric are lithographically patterned so as to each have substantially the same lateral dimensions, e.g., to each have a substantially circular or rectangular lateral shape. In some embodiments, the multilayer nanotube fabric has a thickness from 10 nm to 200 nm, e.g., 10 nm to 50 nm. The structure may include an addressable diode provided under the first conductive terminal or deposited over the second terminal.

Nonvolatile nanotube diodes and nonvolatile nanotube blocks and systems using same and methods of making same

A two terminal memory device includes first and second conductive terminals and a nanotube article. The article has at least one nanotube, and overlaps at least a portion of each of the first and second terminals. The device also includes stimulus circuitry in electrical communication with at least one of the first and second terminals. The circuit is capable of applying first and second electrical stimuli to at least one of the first and second terminal(s) to change the relative resistance of the device between the first and second terminals between a relatively high resistance and a relatively low resistance. The relatively high resistance between the first and second terminals corresponds to a first state of the device, and the relatively low resistance between the first and second terminals corresponds to a second state of the device.

Two-terminal nanotube devices and systems and methods of making same

Identifying marks are often used for authentication and tracking purposes with various types of articles, but the marks themselves can sometimes be subject to replication or removal by an outside entity, such as a person or group having malicious intent. This can make it easier for an outside entity to produce a counterfeit article or to sell a stolen article. Carbon nanotubes and other carbon nanomaterials can be used to form identifying marks that are not visible to the naked eye, thereby making the marks more difficult for an outside entity to tamper with. Various articles can include an identifying mark that is localized and not visible to the naked eye, the identifying mark being electrically conductive and containing a carbon nanomaterial. By electrically interrogating the article, such as through spatially measuring eddy currents about the article, the marks can be located and authenticated.

Articles containing non-visible identifying marks formed from carbon nanomaterials and methods utilizing the same

Under one aspect, a nanotube diode includes: a cathode formed of a semiconductor material; and an anode formed of nanotubes. The cathode and anode are in fixed and direct physical contact, and are constructed and arranged such that sufficient electrical stimulus applied to the cathode and the anode creates a conductive pathway between the cathode and the anode. In some embodiments, the anode includes a non-woven nanotube fabric having a plurality of unaligned nanotubes. The non-woven nanotube fabric may have a thickness, e.g., of 0.5 to 20 nm. Or, the non-woven nanotube fabric may include a block of nanotubes. The nanotubes may include metallic nanotubes and semiconducting nanotubes, and the cathode may include an n-type semiconductor material. A Schottky barrier can form between the n-type semiconductor material and the metallic nanotubes and/or a PN junction can form between the n-type semiconductor material and the semiconducting nanotubes.

A memory array includes a plurality of memory cells, each of which receives a bit line, a first word line, and a second word line. Each memory cell includes a cell selection circuit, which allows the memory cell to be selected. Each memory cell also includes a two-terminal switching device, which includes first and second conductive terminals in electrical communication with a nanotube article. The memory array also includes a memory operation circuit, which is operably coupled to the bit line, the first word line, and the second word line of each cell. The circuit can select the cell by activating an appropriate line, and can apply appropriate electrical stimuli to an appropriate line to reprogrammably change the relative resistance of the nanotube article between the first and second terminals. The relative resistance corresponds to an informational state of the memory cell.

Memory arrays using nanotube articles with reprogrammable resistance

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. A plurality of designs using various geometric orientations of nanotube fabrics, phase change materials, and drive and detection circuitry is disclosed. Additionally, methods of fabricating nanotube heat emitters are disclosed.

Method and system of using nanotube fabrics as joule heating elements for memories and other applications

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.

Light emitters using nanotubes and methods of making same

Field effect devices having channels of nanofabric and methods of making same. A nanotube field effect transistor is made to have a substrate, and a drain region and a source region in spaced relation relative to each other. A channel region is formed from a fabric of nanotubes, in which the nanotubes of the channel region are substantially all of the same semiconducting type of nanotubes. At least one gate is formed in proximity to the channel region so that the gate may be used to modulate the conductivity of the channel region so that a conductive path may be formed between the drain and source region. Forming a channel region includes forming a fabric of nanotubes in which the fabric has both semiconducting and metallic nanotubes and the fabric is processed to remove substantially all of the metallic nanotubes.

Field effect device having a channel of nanofabric and methods of making same

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.

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.

Nonvolatile resistive memories having scalable two-terminal nanotube switches

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.

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Arlington, MA, United States of America

Mitchell Meinhold