Thursday, May 29, 2008

US Patent 7378870 - Symmetrical resistance switching crossbar array

In order to create higher density non-volatile memory designs there has been increased interest in RRAM designs which employ materials which can be programmed to have high or low resistance states based on an applied voltage. Hewlett-Packard and Nantero have extended such designs to the nanoscale using molecular materials such as rotaxane molecules (HP) or carbon nanotube ribbons (Nantero). This is one of my patents covering a symmetrical crossbar structure in which reversal of the switching between the high and low conductivity states can be more easily achieved. For licensing information go to this link. Claim 1 reads:

1. A device comprising:

a first crossbar section including a rectifying layer having a first side and a second side, a first array of wires formed above the first side of the rectifying layer, and a second array of wires formed below the second side of the rectifying layer;

a second crossbar section including a symmetrical structure to the first crossbar section; and

a programmable material layer between the first crossbar section and the second crossbar section.


US Patent 7378701 - Phase change CNT memory

Phase change memory was initially proposed several decades ago by Stanford Ovshinsky but only recently have a variety of other companies been exploring the use of phase change and other materials in new non-volatile memory designs. This patent from Samsung teaches using carbon nanotubes as an interconnect element for phase change memory to achieve higher bit densities. Claim 1 reads:

1. An integrated circuit phase changeable memory device comprising:

an integrated circuit substrate;

a first electrode on the integrated circuit substrate;

a second electrode on the integrated circuit substrate and spaced apart from the first electrode; and

a carbon nano tube and a phase changeable layer serially disposed between the first and second electrodes.


Wednesday, May 28, 2008

US Patent 7378192 - Lithium iron nanoparticle electrode

This patent from Matsushita teaches the use of lithium iron nanoparticles in electrodes of electrolytic batteries that enhance the battery capacity while avoiding decomposition of the electrolyte. Claim 1 reads:

1. A material useful as a positive electrode active material, said material comprising pore free primary particles of an iron compound, wherein the primary particles are 1 to 300 nm, and wherein the iron compound comprises lithium.


US Patent 7378075 - Sol gel CNT alignment

This patent from Mitsubishi teaches a simplified method of forming aligned carbon nanotube bundles having smaller nanotube diameters for applications such as field emission using a sol-gel approach. Claim 1 reads:

1. A process for preparing aligned nanotubes on a porous carrier, the process comprising:

preparing a porous carrier having fine pores of 0.1 to 50 nm by a sol-gel method;

loading a catalyst onto the porous carrier by contacting the porous carrier with a base in an aqueous solution of a metal salt and drying and burning the solution within the pores of the porous carrier; and

depositing a carbon compound on the porous carrier to form a nanotube film aligned perpendicular to the porous carrier.

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Tuesday, May 27, 2008

US Patent 7378040 - Method of forming transparent conductive CNT film

In numerous display and sensor applications the use of transparent electrodes such as ITO or conductive polymers is necessary. However, many of these conductors require additional protective layers which make the formation of external contacts difficult. This patent from Eikos Inc. teaches a method of using carbon nanotubes for transparent electrodes that do not contain such deficiencies. Claim 1 reads:

1. A method of forming a conductive optically transparent coating or film comprising applying to a substrate a layer of carbon nanotubes having an open structure and a separate layer of a applying another layer of material to said carbon nanotube layer that interpenetrates and compresses said carbon nanotubes and increases sheet conductivity across a surface of said conductive film.


US Patent 7377176 - Nanoparticle modified pressure transmitter

This patent teaches a fluid pressure transmitter that uses nanoparticles to reduce overall thermal expansion effects of fluids to improve the operating characteristics of the transmitter. Claim 1 reads:

1. A pressure transmitter for measuring a pressure of a process fluid, the pressure transmitter comprising:

a pressure sensor for sensing the pressure of the process fluid;

a hydraulic relay system for providing a communication channel between the process fluid and the pressure sensor; and a pressure sensor fill fluid in the hydraulic relay system, the pressure sensor fill fluid comprising:

a first hydraulic fluid for transmitting a change in the pressure of the process fluid to the sensor; and

a first volume of nano-particles suspended within the first hydraulic fluid for altering properties of the pressure sensor fill fluid.


Thursday, May 22, 2008

US Patent 7375458 - CNT filament light bulb

The first successful light bulb is often credited to Edison who used carbon treated filaments to produce incandescent light with reasonable lifetimes. However, better materials such as tungsten were later found to improve on the performance of carbon filaments. The tide may be turning back to carbon with the development of carbon nanotubes which this patent from HP uses to create still better filaments. Claim 1 reads:

1. A device comprising:

a carbon-nanotube filament spanning approximately an entire length of the device, the filament being formed of an array of carbon-nanotubes, where a length of a carbon-nanotube is approximately equal to a length of the filament, and where the array of carbon-nanotubes are arranged such that approximately the entire lengths of each carbon-nanotubes are adjacent; electrical contacts in electrical communication with the filament; and

an encapsulant encapsulating the filament and electrical contacts, the encapsulant providing a controlled atmosphere, wherein the filament is configured to emit radiation when an electric current is passed between the electrical contacts and through the filament.

Note: Hon Hai Precision have earlier patented a similar carbon nanotube filament configuration.


US Patent 7375417 - Nanoceramic heat sink for IC package

This patent from independent inventor Bao Tran teaches incorporating carbon nanomaterials into a ceramic host material to create an efficient heat sink for IC cooling. Claim 1 reads:

1. A package for an integrated circuit, comprising:

a chip having a plurality of nodes adapted to receive signals from or to output signals to an external circuit; and

a frame having a plurality of contact points each coupled to one node of the chip; and

a nano ceramic material in thermal communication with the chip for removing heat from the chip.


Wednesday, May 21, 2008

US Patent 7374824 - Tellurium-based quantum dots

This patent from M.I.T. has some fairly early priority going back as far as 1997 and is basic to quantum dots formed from tellurium composite material having relatively high quantum efficiency. Claim 1 reads:

1. A nanocrystallite comprising a nanocrystalline core comprising MTe, an overcoating including a semiconductor material, wherein M is selected from the group consisting of Cd, Zn, Mg, and Hg, and the nanocrystallite photoluminesces with a quantum efficiency of at least 20%.


US Patent 7374649 - CNT separation using nucleic acids

One popular way to sort carbon nanotubes is by using DNA that wraps around carbon nanotubes for diameter based separation. This seems to be the basic patent for this approach. Claim 1 reads:

1. A method for the separation of a carbon nanotube-nucleic acid complex comprising on the basis of diameter:

a) providing a carbon nanotube-nucleic acid complex in solution comprising an unfunctionalized carbon nanotube bound to a nucleic acid molecule wherein the solution comprises a densifying agent;

b) loading the carbon nanotube-nucleic acid complex solution of step (a) on to an electrophoresis gel; and

c) separating the loaded complexes of (b) by applying an electric field to the gel, whereby the carbon nanotube-nucleic acid complex is separated on the basis of the diameter of the carbon nanotube.


Tuesday, May 20, 2008

US Patent 7374613 - High density quantum wire device

This patent from Japan Science and Technology Agency teaches a new way to form high density quantum wire devices using dislocations in ceramics or metals formed via compressions and heat treatment. Claim 1 reads:

1. A quantum wire device comprising a single-crystal material made of ceramic or metal, said single-crystal material internally having dislocations arranged one-dimensionally on respective straight lines at a high density of 106 to 1014/cm2, and quantum wires consisting of metal atoms introduced in said single-crystal material through a diffusion treatment, said quantum wires being arranged along said corresponding dislocations at a high density of 106 to 1014/cm2.


US Patent 7374599 - Method of making dendritic nanostructures

Dendrimers are polymeric nanostructures having a fractal geometric structure which are useful for drug delivery and sensing due to their high surface to volume ratio. This patent from Sandia teaches a method of forming metallic dendritic nanostructures which also share high surface to volume ratio useful to applications such as sensors, solar cells, and catalysis. Claim 1 reads:

1. A method for making dendritic metal nanostructures, comprising:

forming a surfactant structure template in an aqueous solution using a surfactant;

introducing a metal ion from a metal salt and an electron donor species into said aqueous solution containing said surfactant structure template to form a reaction solution; and

reducing said metal ion to form a dendritic metal nanostructure on the surfactant structure template.


US Patent 7373819 - MEMS humidity sensor

For proper operation of fuel cells the humidity should be monitored to determine the rate of supplying feed gases. This patent from Honeywell teaches a MEMS based humidity monitor which may allow for miniaturization of fuel cell technology. Claim 1 reads:

1. A humidity sensing apparatus, comprising:

a substrate; and

a MEMS structure supported by said substrate, wherein said MEMS structure comprises a humidity-sensitive material in association with a mechanical movable member such that when said humidity-sensitive material changes with humidity, said MEMS structure moves said mechanical movable member, thereby providing an indication of humidity based on a stress within said MEMS structure.


Monday, May 19, 2008

US Patent 7372562 - Nanoenhanced Raman spectroscopy using turbulance

Raman spectroscopy is a molecular detection and characterization tool that takes advantages of nanoscopically roughened or nanoparticle metallic surfaces to enhance the detection efficiency. this variation from Hewlett-Packard teaches applying vibrations that alters the spacing between metallic nanoparticles used in Raman spectroscopy to further enhance the sensitivity. Claim 1 reads:

1. A nano enhanced Raman spectroscory (NERS) system comprising:

a radiation source;

a radiation detector configured to detect Raman scattered radiation scattered by an analyte;

a container configured to provide a sealed enclosure; and

a turbulence generating device configured to generate mechanical vibrations causing random dynamic motion of a plurality of nanoparticles each comprising a NERS-active material within the container.


US Patent 7372033 - Quantum dot color wheel filter

Color filter wheels are a common component to many multi spectral imaging systems. This patent from Lockheed Martin teaches using quantum dots as the filtering component for such color wheels. Claim 1 reads:

1. A device for filtering radiation from a target region in multiple spectral bands, comprising:

a rotatable disk;

a number of optical quantum dot filters, wherein each of the number of optical quantum dot filters is positioned on the rotatable disk, and wherein each of the number of optical quantum dot filters positioned on the rotatable disk has a particular pass-through wavelength range.


Thursday, May 15, 2008

US Patent 7371696 - Vertically aligning CNTs using self-assembled monolayer

A variety of methods exist for aligning carbon nanotubes for device applications but many rely on either CVD, which requires high temperatures, or electrostatic alignment, which can produce less than satisfactory results. This method from Samsung teaches an alternative based on the use of a self assembled monolayer to facilitate the alignment. Claim 1 reads:

1. A method of vertically aligning Carbon NanoTubes (CNTs), the method comprising:

forming a first conductive substrate;

stacking a CNT support layer having a plurality of pores on the first conductive substrate;

attaching one end of the each of the CNTs to portions of the first conductive substrate exposed through plurality of pores; and

forming a Self-Assembled Monolayer (SAM) including a functional group having a chemical affinity for the plurality of CNTs on the surface of the first conductive substrate after its formation.


US Patent 7371674 - Nanowire template interconnect

In order to grow parallel arrays of vertical nanowires or nanotubes from a substrate one popular method is the use of nanoporous alumina templates. This technique has been applied to form well-ordered dense arrays of carbon nanotube field emitters for displays as will as a variety of sensor structures. This patent from Intel teaches using such templates to form interconnect wiring for IC packaging. Claim 1 reads:

1. A method comprising:

forming a nanostructure bump on a die, the nanostructure bump having a template defining nano-sized openings and metallic nano-wires grown from the nano-sized openings; and

attaching the die to a substrate via the nanostructure bump.


Wednesday, May 14, 2008

US Patent 7371666 - Fabrication of photoluminescent silicon nanoparticles

Photoluminescence is a common phenomena in quantum dots made from a variety of semiconductor materials useful for biotags and electro-optic devices such as sensors and lasers. This patent from the State University of New York teaches a manufacturing process for photoluminescent silicon nanoparticles capable of greater volume of production than prior processes. Claim 1 reads:

1. A process for producing photoluminescent silicon nanoparticles comprising:

reacting a silicon precursor in the presence of a sheath gas with heat from a radiation beam under conditions effective to produce silicon nanoparticles and

acid etching the silicon nanoparticles under conditions effective to produce photoluminescent silicon nanoparticles.


US Patent 7371457 - Core/shell optical nanoparticles

This patent from Rice University has fairly early priority (3/12/1997) and is basic to core/shell optical nanoparticles. Although not the first to teach such particles (see U.S. 5,023,139) the nanoparticles of the prior art are noted as not taking into account surface scattering and to have broader spectra whereas the claimed nanoparticles have a thin metallic shell layer providing a smaller electron mean free path for applications such as Surface Enhanced Raman Spectroscopy. Claim 1 reads:

1. A nanoparticle comprising:

at least one non-conducting inner layer;

at least one conducting shell layer surrounding the inner layer, the thickness of said shell layer being independent of the radius of said inner layer and less than the bulk electron mean free path of the material comprising the shell layer.


Tuesday, May 13, 2008

US Patent 7371456 - Nanoparticle ink with charged particle protective layer

This patent from Kimberly-Clark Worldwide teaches an improved textile ink more resistant to fading and bleeding than prior inks and based on nanoparticulate materials. Claim 1 reads:

1. An ink composition for a printing process comprising:

a nanoparticle having a size less than about 1,000 nanometers comprising a particle template having more than one colorant layer disposed upon the particle template;

a liquid vehicle; and

a protective layer disposed upon the colorant layer; wherein the protective layer is a charged polymer.


US Patent 7370530 - 3-axis MEMS package

One of the most active applications of MEMS devices is in the area of inertial sensors such as gyroscopes and accelerometers. In some application more than one axis of motion needs to be monitored in which case multiple MEMS sensors may be required. This patent from Honeywell teaches a housing structure designed to minimize the size of such multi-dimensional inertial sensors. Claim 1 reads:

1. A package, comprising:

a packaging structure having a first sidewall, a second sidewall, and a third sidewall, joined to define an interior cavity, the packaging structure further having a planar top member coupled to a first end portion of the respective sidewalls and a bottom lid coupled to an opposite end portion of the respective sidewalls, the planar top member distally located from the bottom lid, the respective sidewalls, top member, and bottom lid cooperating to enclose the interior cavity;

a first MEMs device mounted within the interior cavity and on an inner wall surface on the first sidewall;

a second MEMs device mounted within the interior cavity and on an inner wall surface of the second sidewall; and

a third MEMs device mounted within the interior cavity and on an inner wall surface of the third sidewall.


Monday, May 12, 2008

US Patent 7368712 - Functionalized Y-junction carbon nanotube AFM tip

Due to their high-aspect ratio carbon nanotube have been grown on the tips of atomic resolution probes to inspect trench structures more easily. This patent from IBM teaches using a functionalized Y-shaped carbon nanotube as the tip offering additional benefits for chemical detection on the molecular scale. Claim 1 reads:

1. A Y-shaped carbon nanotube atomic force microscope probe tip comprising: a shaft portion; a pair of angled arms extending from a same end of said shaft portion, wherein said shaft portion and said pair of angled arms comprise a chemically modified carbon nanotube, and wherein said chemically modified carbon nanotube is modified with any of an amine, carboxyl, fluorine, and metallic component.


US Patent 7368263 - Nucleic acid circuit element with conductive coatings

The use of nucleic acids for constructing circuit elements is of interest since it allows for self-assembly of the components and provides the possibility of 3D circuit architectures. This patent with fairly old priority (May 1998) seems fairly fundamental to a nucleic acid circuit element.

1. A circuit comprising:

at least one circuit element, the circuit element comprising at least one of a resistor, a diode, a capacitor, a transistor, and an inductor; wherein the at least one circuit element comprises a nucleic acid template with two or more sequential regions which are coated with different materials that are at least partially conductive.


Wednesday, May 07, 2008

US Patent 7367999 - Method of producing nanoparticle film using sputtering

This patent from Fujifilm teaches a method of producing nanoparticles of a larger variety of compositions and which is less subject to agglomeration. Claim 1 reads:

1. A method of producing ultrafine particles by vaporization comprising:

vaporizing a target by sputtering;

causing particles that fly from the target by vaporization to be deposited on an oil surface; and

recovering the oil on which the flown particles have been deposited to obtain individually dispersed ultrafine particles, wherein the target is a multi-element compound.


US Patent 7367934 - Enhancement of tumor treatment using metal nanoparticles

This patent from a company called Nanoprobes teaches using metal nanoparticles to enhance x-rays for treating tumors. Claim 1 reads:

1. A method for enhancing the effects of radiation directed to a tissue or a population of cells in an animal, comprising

administering an amount of metal nanoparticles to said animal to achieve a concentration in said tissue or said population of cells of the animal of at least about 0.1% metal by weight; and

subsequently irradiating the animal with radiation directed to said tissue or said population of cells, wherein said radiation is in the form of x-rays of about 1 keV to about 25,000 keV.


Tuesday, May 06, 2008

US Patent 7367505 - Quantum dot dispensing and detecting

This patent from Caltech (priority June 12, 2003) teaches methodology for using quantum dots for optical coding. Claim 1 reads:

1. A method of dispensing and detecting fluorescent quantum dots, comprising:

dispensing said dots on a surface at a plurality of locations where each location includes quantum dots of a plurality of center wavelengths;

exciting said dots with a UV light until said dots fluoresce; and

analyzing said fluorescence with a spectrometer.

Unfortunately some pertinent prior art may have been overlooked such as:

US Patent 6617583- "A novel encoding system and methods for determining the location and/or identity of a particular item or component of interest is provided. In particular, the present invention utilizes a "barcode" comprising one or more sizes of semiconductor nanocrystals (quantum dots) having characteristic spectral emissions, to either "track" the location of a particular item of interest or to identify a particular item of interest. " (from abstract)


US Patent 7367215 - Nanowire antifuse hydrogen sensor

This patent from Nano-Proprietary teaches using nanowires for a hydrogen sensor in which an increase in hydrogen concentration gradually allows current flow between the nanowire junctions. Claim 1 reads:

1. A method comprising the steps of: a) forming, directly on a dielectric surface, at least one precisely-defined metal-alloy nanowire comprising nanobreakjunctions which close when exposed to predefined threshold concentrations of hydrogen; b) forming a circuit comprising said nanowire; and c) monitoring an electrical property within said circuit so as to determine when said nanobreakjunctions close.


Thursday, May 01, 2008

US Patent 7365632 - Carbon nanotube nanofabric thin film resistor with improved temperature independence

Certain electronic circuits such as voltage regulators and data converters require a high degree of temperature independence to operate properly. This patent from Nantero teaches how to form thin film resistors formed from carbon nanotube fabrics with a sheet resistance in a range of 1 kohm/square - 1 Mohm/square in which the resistance changes by less than 25 parts per million per degree centigrade which is a factor of 10 better than similar thin film resistors. Claim 1 reads:

1. A resistive element, comprising:

a patterned region of nanofabric with a predefined area and a pre-selected sheet resistance, the nanofabric having a pre-selected temperature coefficient of resistance (TCR); and

first and second electrical contacts contacting the patterned region of nanofabric and in spaced relation to each other, wherein

a total resistance of the resistive element between the first and second electrical contacts is determined by the predefined area of the patterned region of nanofabric, the pre-selected sheet resistance of the patterned region of nanofabric between the first and second electrical contacts, and the pre-selected TCR of the nanofabric, and the spaced relation of the first and second electrical contacts; and

wherein the total resistance of the resistive element is tunable to a pre-selected total resistance.


US Patent 7365395 - Dielectric composites including core/shell nanowires

This patent from Nanosys teaches the creation of artificial high-k dielectrics formed from nanowire composites. Advantageously by controlling the density and the distribution of the nanowires the dielectric constant of the composite may be tuned to various values depending on the application. Claim 1 reads:

1. An artificial dielectric device, comprising:

a first conducting element and a second conducting element spaced apart from and opposing said first conducting element;

a dielectric disposed between said first and second conducting elements and comprising a material selected from the group comprising a plastic, a metal oxide, a glass, a semiconductor, diamond, sapphire or quartz; and

a plurality of nanostructures embedded in said dielectric material, said nanostructures comprising a plurality of nanowires each comprising a semiconductor core and an insulating shell comprising an oxide, carbide or nitride coating disposed about said core, wherein said nanowires are oriented substantially parallel to each other with their long axes substantially perpendicular to the first and second conducting elements such that said nanowires have anisotropic orientations within said dielectric, wherein at least subset of said nanowires do not make direct contact to either said first or second conducting element.