Friday, November 30, 2007

US Patent 7302513 - Programmable crossbar architecture for signal processing

Crossbar architectures have been used in signal interconnects in a variety of communication applications and, more recently, in forming arrays for molecular and thin film memories. This patent is based on ideas I had a couple of years ago for implementing a molecular or thin film crossbar array to perform the function of a programmable linear transform for signal processing which has applications in the areas of waveform generation, programmable filter design, and frequency hopping communication schemes. Claim 1 reads:

1. A signal processor comprising:

a crossbar array including one or more materials or molecular components formed between intersections of the crossbar array wherein the one or more materials or molecular components is programmable so as to have a corresponding programmed impedance value Zij at each of the intersections, where i is an integer ranging from 1 to N, j is an integer ranging from 1 to M, N corresponds to a number of input wires in the crossbar array, M corresponds to a number of output wires in the crossbar array, at least one of N or M is equal or greater than 2 and the other one of N or M is equal to or greater than 1;

an input unit providing a set of N input signals Vin(i) directed toward the input wires of the crossbar array; and

an output unit outputting a set of M output signals Vout(j) derived from the output wires of the crossbar array,

wherein the crossbar array, input unit, and output unit are constructed so that each of the programmed impedance values Zij uniquely determines a corresponding value Tij such that Vout(j)= SUM [Tij x Vin(i)], which is a summation performed for i from 1 to N.


Thursday, November 29, 2007

US Patent 7301779 - CNT chip interconnects

In order to connect multiple electronic circuit chips together a variety of methods are known using solder and wire bond connections. This patent from Infineon teaches using carbon nanotubes as electrical interconnect elements to provide better mechanical flexibility and current carrying ability than prior interconnect materials. Claim 1 reads:

1. An electronic chip assembly comprising: a first electronic chip; a second electronic chip; the first electronic chip having a plurality of external chip contacts to which a multiplicity of nanotubes are applied in order to make contact between the first electronic chip and the second electronic chip; the second electronic chip having a plurality of external chip contacts that are free of nanotubes and that can be brought into contact with the nanotubes that have been applied to the external chip contacts of the first electronic chip; and wherein the nanotubes of one external chip contact of the first electronic chip are brought into contact with one external chip contact of the second electronic chip.


US Patent 7301199 - Nanowire FETs with uniform diameter

This patent from Charles Lieber's group at Harvard teaches catalytically grown uniform diameter nanowires used in forming field emission transisistor structures. Claim 1 reads:

1. An electrical component comprising a plurality of field-effect transistors each comprising first and second electrodes and a non-nanotube semiconductor nanoscale wire electrically coupling the first and second electrodes, wherein each of the nanoscale wires of the component comprises at least one portion having a smallest width of less than 500 nanometers, and wherein each of the nanoscale wires of the component is taken from a population of nanoscale wires having a variation in average diameter of less than 20% relative to each other, the population of nanoscale wires being grown catalytically from a population of catalyst particles having a variation in diameter of less than 20%, wherein the diameter of each of the nanoscale wires is determined by the diameter of the catalyst particle from which the nanoscale wire is grown, and wherein each of the nanoscale wires is doped during growth of the nanoscale wire from the catalyst particle.


Wednesday, November 28, 2007

US Patent 7301172 - Sequentially charged nanocrystal LED

In order to produce more efficient LEDs using quantum dots this patent from CalTech teaches separating the electrons and holes injections by using an AC excitation method. Claim 26 reads:

26. A method of emitting light from a light emitting device including a transistor structure formed on a semiconductor substrate and having a source region, a drain region, a channel region between the source and drain regions, a gate oxide on the channel region, and a plurality of nanocrystals embedded in the gate oxide, the method comprising: injecting first type charge carriers into the nanocrystals; and after injecting the first type charge carriers, injecting second type charge carriers into the nanocrystals, such that the first and second type charge carriers form excitons used to emit the light.


US Patent 7301109 - CNT/Ni/Cu/Ni EMI shield

With the increase in mobile wireless electronics problems related to electromagnetic interference (EMI) are increasing. This patent from Hon Hai Precision teaches an EMI shield for electronics devices that uses carbon nanotubes a laminate structure which is resistant to wear. Claim 1 reads:

1. A wear resistant electromagnetic interference (EMI) shield for application to various substrate surfaces of electronic equipment, comprising sequentially: a metallic film or multiple metallic films in which at least one film contains nickel; and a carbon-nanotube (CNT) coating formed on a surface of said metallic film or multiple metallic films; wherein said metallic film or multiple metallic films cooperate with the carbon-nanotube coating to shield EMI coming from the electronic equipment; and said multiple metallic films include one copper film and two nickel films, with the EMI shield having a structure of CNT/Ni/Cu/Ni/.


Tuesday, November 27, 2007

US Patent 7300860 - Nanotube IC formed using spin coating

This patent from Intel teaches a process for incorporating carbon nanotubes into the fabrication processes for integrated circuits. Claim 1 reads:

1. A method of fabricating an integrated circuit comprising: forming or providing a solution containing metal ions and carbon nanotubes; and co-depositing the metal ions and carbon nanotubes onto a substrate utilizing the solution to form a metal layer, said co-depositing including spin-coating onto the substrate at a rotation speed of between about 20 and about 100 rpm for a time of between about 1 and about 5 minutes and annealing the substrate at a temperature of between about 200 and about C. for a time of between about 1 and about 200 minutes.


US Patent 7300634 - CNT field emission for air purification

Ultraviolet light is used in various purification systems. Many of these systems use fluorescent lamps as the source of the ultraviolet light which have limited life expectancies, take time to fully turn on and can be toxic to the environment. This patent form Nano-proprietary teaches an alternative using field emission cathodes (such as carbon nanotubes) in ultraviolet sources for air or water purification. Claim 1 reads:

1. A photocatalytic cleaner for air or water, comprising: a photocatalytic material coating a substrate; an anode, positioned a predetermined distance from the substrate, comprising a phosphor adapted to emit ultraviolet light in response to bombardment by electrons; and a field emission cathode, positioned a predetermined distance from the anode, operable for emitting electrons in response to an electric field.


Wednesday, November 21, 2007

US Patent 7298016 - Patterned nanotube ribbons for crossbar circuit

Nantero continues to dominate carbon nanotube electronics (at least in terms of # of patents) with this latest patent focusing on lithographically patterned nanotubes formed relative to a conductive trace. Claim 1 reads:

1. A circuit comprising: a structure having a conductive trace; and lithographically patterned element of pre-defined shape formed from a nanotube layer disposed in spaced separation from the conductive trace.


US Patent 7298014 - MEMS noise reduction using viscoeleastic polymer

Some micromechanical applications can be very sensitive to noise or vibration. This patent from Honeywell teaches using visco-elastic polymer coatings for MEMS devices which can absorb such noise or vibrations and avoid help error. Claim 1 reads:

1. A component, comprising: a microelectromechanical system (MEMS) device positioned within an enclosure; and one or more layers of a visco-elastic polymer situated around at least part of an outer surface of the enclosure, said visco-elastic polymer configured to convert acoustic energy and vibration energy into heat.


Tuesday, November 20, 2007

US Patent 7297946 - Automated nanoassembly

Tools for nanomanipulation have been developed since the late 1980's and 1990's by researchers at IBM working with scanning tunneling and atomic force microscopes. More recently companies such as Daiken Chemical and Zyvex have made proposals for alternative systems using nanotweezers and other scanning probe tools. This patent from researchers at Michigan State University proposes an automated system of nanoassembly starting from a random distribution of nanostructures and which takes advantage of computer aided design (CAD) techniques. Claim 1 reads:

1. An automated nanomanipulation system for manufacturing a nanoscale structure, comprising: a design model for a nanoscale structure comprised of two or more nanoobjects; image data of a sample surface upon which the nanoscale structure is to be manufactured, the sample surface having a plurality of randomly distributed nanoobjects from which the nanoscale structure is formed; a movable member configured to perform a nanomanipulation operation on the sample surface; a path planning subsystem adapted to receive the design model and the image data and operable to generate path data is indicative of a path for traversing the movable member along the sample surface such that the movable member manipulates one or more randomly distributed nanoobjects in accordance with the design model, and the path data.


US Patent 7297281 - Nanoporous inner coating for filtering

A variety of nanoporous materials have been proposed for filters in which a fluid to be filtered is passed through the nanoporous material to remove impurities. This invention presents a somewhat interesting alternative in which the nanoporous material is placed on an inner surface of a water bottle (or similar container) and acts to absorb contaminants from the water passing across (but not through) the inner surface. Claim 1 reads:

1. A system for purification of fluid, the system comprising:
a receptacle;
a chamber situated within the receptacle and into which a volume of fluid to be treated may be placed; and
a porous matrix, positioned within the chamber, having a plurality of nanoscaled pores dispersed therein, such that fluid having particulates and/or contaminants flowing across one surface of the matrix flows back out along the same surface of the matrix substantially without the particulates and contaminants;
wherein the nanoscaled pores of the porous matrix are dispersed between a fluid contact surface across which fluid may flow and a substantially fluid impermeable surface, such that fluid flowing across the contact surface into the pores of the matrix flows back out along the contact surface.


Monday, November 19, 2007

US Patent 7295506 - Elliptical nanotip for scanning probe memory

Scanning probe tips can have radius of curvature in the nanometer range which allows them to produce high resolution marks useful in data storage. However tips with faceted or narrow cross-sectional diameter may be difficult to accurately position relative to a pit of a storage medium during a read operation. This patent from Hewlett-Packard discloses an elliptical shape tip to aid in positioning. Claim 1 reads:

1. A device comprising: a substrate comprising at least one pit having a substantially elliptical shape; a probe having a tip, wherein the tip contains a substantially elliptical cross-sectional shape, and wherein the tip is used to create the at least one pit in the substrate; and wherein one or both of the substrate and the probe are configured to move with respect to each other such that the tip is moved into and out of the at least one pit through the relative movement.

However some relevant prior art such as US 5,503,010 (Figs. 3, 4, 10) and US 6,218,086 (Fig. 2) may have been overlooked during the examination.


US Patent 7295503 - Electron emitting nanotubes for data storage

One of the key properties of carbon nanotubes that is being exploited in proposed commercial devices is their capacity for high electron emission with low threshold voltages. This is one of a group of related patents to Hewlett Packard which capture the use of such field emission nanotube arrays for data storage. Claim 1 reads:

1. A data storage device comprising an array of nanotubes as electron field emission sources.


Thursday, November 15, 2007

US Patent 7295419 - Inorganic nanofiber capacitor

Due to their high surface-to-volume ratio nanomaterials have been used in forming a variety of capacitor structures which depend on large surface area to achieve high capacitances. This patent goes to Nanosys for an embodiment of a capacitor including inorganic nanofibers in a dielectric matrix. Claim 1 reads:

1. A capacitor comprising first and second opposing electrodes and a dielectric layer disposed between the first and second electrodes, wherein the dielectric layer comprises a plurality of inorganic nanofibers and a dielectric which covers substantially all members of the plurality of nanofibers.


US Patent 7294899 - Nanowire filament fused conductor

This patent from Hewlett-Packard teaches using fused nanowires to connect two closely spaced metal conductors to construct a Wheatstone Bridge circuit, a thermocouple, or other circuitry. Claim 1 reads:

1. A circuit, comprising: first and second close proximity metal conductors; and a nanowire filament fused between the close proximity conductors, the nanowire filament comprising a fusion of metal from the first close proximity conductor and metal from the second close proximity conductor.


Wednesday, November 14, 2007

US Patent 7294417 - Branching metal oxide nanostructures

There are a variety of metal oxide nanostructures known but most are in the form of simple particulate or one-dimensional structures. This patent from Boston College teaches the formation of more complex metal oxide nanostructures having high surface to volume characteristics. Claim 24 is representative.

24. A metal oxide material comprising: a central three-dimensional nanostructure having a linear axis formed from at least one metallic oxide; and at least three three-dimensional nanostructures formed from at least one metallic oxide, wherein a distal end of each of the three-dimensional nanostructures is attached to the central three-dimensional nanostructure between a first end and a second end of the central three-dimensional nanostructure.


US Patent 7294388 - Resin and nanoparticle lubrication material

This patent focuses on the use of silica nanoparticles in high coefficient of friction materials for continuous torque transmission systems which can withstand high speeds and have high heat resistance. Claim 1 reads:

1. An oil lubricated friction material for use in a clutch or brake comprising a first layer comprising a fibrous base material and at least one resin material, and a second layer comprising nanoparticle-sized friction modifying particles on a top surface of the base material, the second layer of the nanoparticle-sized friction modifying particles having a thickness of about 10 nm to about 250 .mu.m, wherein the nanoparticle-sized friction modifying particles have an average diameter size from 10 nm to 150 nm, and wherein the nanoparticle layer covers 3 to 99%, by area, of the base material.


Tuesday, November 13, 2007

US Patent 7294372 - Carbon nanotubes for color filter

Conductive color filters are useful in display applications to provide conductive paths to control circuitry while regulating the colors of display pixels. This patent from Kodak discloses the use of carbon nanotubes with a resin colorant to construct such filters. Claim 1 reads:

1. An array of electrically connected conductive color filters, wherein each conductive color filter is in electrical contact with a transparent conductive electrode, at least one conductive color filter comprising an unpatterned layer of carbon nanotubes covered by a patterned layer of colored polymeric resin binder, wherein the color of the colored polymeric binder is black, red, green or blue.


US Patent 7294340 - Nanodiamonds for cosmetics

Several companies such as L'Oreal have been working with polymeric and metallic nanoparticles for cosmetic applications. This patent discloses the use of nanostructured diamond for similar purposes. Claim 1 reads:

1. A remedial healthcare nanodiamond composition, comprising: a) a biologically acceptable carrier; and b) a plurality of nanodiamond particles dispersed in the carrier with a dispersant, said nanodiamond particles having an average size of from about 0.5 nm to about 50 nm.

US Patent 7294248 - Electron emission nanostructure formed using electrophoretic deposition

For field emission displays and other devices that employ nanostructures for electron emission there are two methodologies of manufacture - 1) prefabrication of the nanostructure which is used as an emissive coating for electrodes on a substrate or 2) direct fabrication of the nanostructure on the substrate. The first method has several advantages in that the manufacturing process can be performed more cheaply using printing and deposition technologies at lower temperatures than direct fabrication. However, deposited nanostructures have a random orientation that are not optimal for directed field emission. This patent from Xintek, Inc. teaches a method of nanostructure deposition that can form directed field emission nanostructures. Claim 1 reads:

1. A method of forming an electron emitter, the method comprising the steps of: (i) forming a nanostructure-containing material; (ii) forming a mixture comprising nanostructure-containing material and a matrix material; (iii) depositing a layer of the mixture onto at least a portion of at least one surface of a substrate by electrophoretic deposition; (iv) sintering or melting the layer thereby forming a composite; and (v) electrochemically etching the composite to remove matrix material from a surface thereof, thereby exposing nanostructure-containing material.

Labels: ,

Monday, November 12, 2007

VirtualRealityIP - New patent blog

I recently started a new patent blog focusing on a review of recently issued U.S. patents devoted to important (in my humble opinion) or broad patents in the area of interactive audio and visual electronic systems. Check it out at -

and don't forget to check out my other blog for reviews of important U.S. patents in pattern recognition, robotics, and A.I. at

Friday, November 09, 2007

US Patent 7292440 - Heat dissipating carbon fiber sheet for plasma display

This patent from Samsung focuses on using intersecting carbon fibers separated by resin material to form a better heat dissipation sheet for plasma displays and other electronic devices. Claim 9 reads:

9. A heat dissipating sheet installed at a heat generator for dissipating heat, the heat dissipating sheet comprising: a resin material; and carbon fibers fixed in the resin material; wherein the carbon fibers are arranged along at least two different directions relative to each other, and are entirely separated from each other by the resin material.


US Patent 7292334 - Enhanced Raman spectroscopy using plural nanoparticle types

This patent from Hewlett Packard finds a combination of metallic nanoparticles (Au, Ag, Cu) with inactive nanoparticles (colbolt, silica, alumina) has the effect of enhancing Raman spectroscopy. Claim 1 reads:

1. A two-dimensional array of nanoparticles usable for enhancing Raman scattered radiation in NERS comprising: a first plurality of nanoparticles; and a second plurality of nanoparticles of size and shape substantially similar to the size and shape of the first plurality of nanoparticles, the second plurality of nanoparticles exhibiting a plasmon frequency differing from any plasmon frequency exhibited by the first plurality of nanoparticles, the second plurality of nanoparticles being interspersed among the first plurality of nanoparticles in the two-dimensional array of nanoparticles.


Thursday, November 08, 2007

US Patent 7291598 - Nanoparticles for insulin delivery

This patent from GP Medical and National Tsing Hua University discloses a chemical composition for nanoparticulate insulin delivery to treat diabetes. Claim 1 reads:

1. A method of treating diabetes of a patient comprising orally administering insulin containing nanoparticles with a dosage effective amount of said insulin to treat said diabetes, wherein at least a portion of said nanoparticles comprises chitosan substrate and poly(glutamic acid).

Labels: ,

US Patent 7291319 - Arc shaped CNT stacks

This patent from researchers of Tsinghua University and Hon Hai Precision Industry teaches that the thickness of catalyst layers can be used to control growth rates of carbon nanotube arrays. This can be useful in creating bent and arcing shapes of carbon nanotubes which may be useful in forming electrical interconnects and other structures. Claim 1 reads:

1. A carbon nanotube-based device comprising: a substrate; a catalyst layer formed on the substrate, the catalyst layer comprising a plurality of catalyst blocks, each catalyst blocks being thicker gradually from a first end thereof to an opposite second end thereof, and the catalyst blocks each having a region with a thickness approximately equal to an optimum thickness for growing carbon nanotubes; and a plurality of carbon nanotube arrays extending from the catalyst blocks, the carbon nanotube arrays being arc-shaped, and bending in respective directions of deviating from the region of optimum thickness.

Labels: ,

Wednesday, November 07, 2007

US Patent 7291318 - Transforming nanopeapods to double wall nanotubes

Some fullerene manufacturing processes produce peapod carbon structures with C60 (buckyballs) encapsulated within a single walled carbon nanotube. This patent from Toyota teaches a method to transform these "nanopeapods" into double walled carbon nanotubes. Claim 1 reads:

1. A method for manufacturing multi-wall carbon nanotubes comprising: a process for preparing fullerene/carbon nanotube hybrid structures wherein assembled fullerenes, these being fullerenes that are linked, are housed within carbon nanotubes, and a process whereby the hybrid structures are subjected to electron beam irradiation while in a heated state, thereby forming interior tubes from the assembled fullerenes; wherein the hybrid structures are subjected to irradiation with the electron beams while in a state of being heated to


US Patent 7291284 - Resist coating using dip pen nanolithography

Scanning probe instruments such as atomic force microscopes and near-field probes have been proposed since the 1980's for a variety of semiconductor manufacturing processes such as etching and curing of resists. Nanoink is a company that is expanding on the capability of scanning probe tools by using a process called dip pen nanolithography (DPN) that is adapted to use the tip of atomic force microscopes to transfer chemical substances with nanoscale line widths to a substrate. This patent seems fairly fundamental and captures the use of DPN in forming resist patterns for high resolution lithography processes. Claim 1 reads:

1. A method of nanolithography comprising: providing a substrate and a nanoscopic or SPM tip; using the tip to apply a patterning compound from said tip to the substrate so as to produce a desired pattern which is a chemical etching resist; and chemically etching the substrate.


Tuesday, November 06, 2007

US Patent 7290916 - Field emission nanotip light source

While much of the interest in field emission nanomaterials has so far focused on flat panel displays, a variety of other applications are emerging such as for lighting. This patent from Hon Hai Precision teaches backlighting and other illumination devices using nanotips formed of electron emissive metals such as molybdenum, niobium, or tungsten formed on SiC or diamondlike carbon isolation posts. Claim 1 reads:

1. A light source comprising: a substrate having a surface; a cathode with at least one substantially solid-cross-section electron emitter formed thereon, the cathode being located on the surface of the substrate, each electron emitter including an isolating post extending from the isolating layer and a nano-tip formed on a top end of the respective isolating post, the nano-tip being comprised of an emissive metal material; an isolating layer formed on the cathode; a light-permeable anode facing the field emitters and being spaced from the cathode to form a vacuum chamber; and at least one fluorescent layer formed on the anode.


US Patent 7290667 - CNT filter for microfluidics

This patent from the University of California teaches a carbon nanotube filter formed in a microfluidic channel. The carbon nanotube mesh can be dimensionally tuned and functionalized to allow for selective discrimination of molecules in a variety of applications. Claim 1 reads:

1. A microfluidic sieve comprising: a substrate having a microfluidic channel; and a compressed carbon nanotube mesh comprising a plurality of intertwined free-standing carbon nanotubes fixedly attached within and randomly extending from the surface of said channel to form irregularly sized mesh pores between the intertwined nanotubes for separating, concentrating, and/or filtering molecules flowed therethrough; and a cover layer sealably capping said microfluidic channel to thereby pack and compress the carbon nanotube mesh in the microfluidic channel, wherein said mesh partially fills a cross-section of the channel to form a central gap therethrough.


Friday, November 02, 2007

US Patent 7289357 - Output isolation for nanotube switch

This patent from Nantero deals with electrical isolation between the an output terminal and carbon nanotube mechanical switches which is important for the construction of a variety of logic circuits. Claim 1 reads:

1. An isolation structure for a deflectable nanotube element, comprising: a pair of electrodes disposed on opposite sides of a deflectable nanotube element, at least a portion of the deflectable nanotube element being anchored to a support structure, at least one of said pair of electrodes being an output terminal for a signal carried on the deflectable nanotube element, said pair producing substantially the same but opposing electrostatic forces on the deflectable nanotube element, so that the position of the deflectable nanotube element near the pair of electrodes is substantially unaffected by the electrical state of the output terminal; and a control electrode disposed between the support structure and one of the pair of electrodes so as to control the position of the deflectable nanotube element.


Thursday, November 01, 2007

US Patent 7288970 - Volatile switch using nanotube channel

Usually non-volatile memory is more desirable than volatile memory because the store of information is independent of a continued supply of power. However, this patent from Nantero claims carbon nanotube switches in a volatile configuration which may be beneficial to higher speed switching electronics.

1. An integrated switching device, comprising: a signal input terminal; an output terminal; and a control structure including at least one control input terminal, electrical stimulation of said control structure controlling formation of a controllably-formable electrically conductive channel between the signal input terminal and the output terminal, a first portion of the electrically conductive channel including a nanotube channel element and a second portion of the electrically conductive channel including a field modulatable semiconductor channel element, wherein the integrated switching device is volatile.


US Patent 7288783 - Quantum dots formed on a curved surface

In optical communication systems a wide band of wavelengths introduce differences in polarization which can limit optical amplification. The inventor behind this patent from Fujitsu Ltd. realized that formation of quantum dots on a curved surface can provide optical amplification independent in polarization allowing for use in wideband applications . Claim 1 reads:

1. An optical semiconductor device comprising: an active layer including a plurality of quantum dots; a lower clad layer formed below the active layer; and an upper clad layer formed above the active layer, said plurality of quantum dots being formed on a plurality of surfaces whose normal directions are different from each other, wherein each surface has a normal direction different from a normal direction of any one of the other surfaces, and said plurality of quantum dots are formed on each surface, respectively, the quantum dots are formed on a curved surface.