Tuesday, October 31, 2006

US Patent 7128889 - Nanodiamond Film

http://www.freepatentsonline.com/7128889.pdf

Diamond films are useful for protective films and other coatings for their hardness and thermal conductivity. Ultrananocrystalline diamond has been used for these films in the past but such films have included microcrystalline diamond as well. This patent teaches using a plasma enhanced CVD method to form nanocrystalline diamond films of higher purity. Claim 1 reads:

1. An ultrananocrystalline diamond (UNCD) film having an average grain size between 3 and 5 nanometers (nm) with not more than about 8% by volume diamond having an average grain size larger than 10 nm.

Monday, October 30, 2006

US Patent 7126207 - Capacitor with Carbon Nanotubes

http://www.freepatentsonline.com/7126207.pdf

High capacitance circuit elements are useful for decoupling power supplies from high frequency noise. Since capacitance is directly related to the interface area between two separated electrodes, very high capacitances can be achieved using high surface-to-volume materials. This patent from Intel teaches the formation of a capacitor from an array of vertically oriented nanotubes. Claim 1 reads:

1. A capacitor, comprising: a substrate defining a first electrical terminal; a catalyst layer disposed on the substrate; a plurality of carbon nanotubes disposed on the catalyst layer and electrically coupled through the catalyst layer to the substrate; a dielectric layer disposed over the plurality of carbon nanotubes; and a conductive layer disposed on the dielectric layer and defining a second electrical terminal.

Thursday, October 26, 2006

US Patent 7126136 - Nanoparticle Optical Storage Medium

http://www.freepatentsonline.com/7126136.pdf

DVDs and CDs are examples of optical storage media that operate based on reflection or non-reflection of light depending on the location of pits on the surface of the CD/DVD. This patent proposes a similar system except it uses nanoparticles instead of pits for a higher resolution memory. Claim 1 reads:

1. An imaging plate for use in a digital imaging system to store energy patterns, comprising: a substrate; and a nanoparticle thin film supported by the substrate, the nanoparticle thin film formed of nanoparticles which cooperate to store energy that is indicative of latent images when the nanoparticles are exposed to such energy.

US Patent 7125605 - >30% Quantum Yield Nanocrystals

http://www.freepatentsonline.com/7125605.pdf

Quantum dots (i.e. nanocrystals) are useful for biological tags and in optoelectronic applications such as lasers, radiation sensors, and displays. The size of the quantum dots can be tuned to emit or absorb light of specific frequencies. An important parameter characterizing quantum dots is "quantum yield" which refers the ratio of emitted photons (light) to absorbed photons. This patent from M.I.T. claims-

1. A population of coated nanocrystals each comprising a size-selected core including a first semiconductor material and an overcoating including a second semiconductor material, wherein the population of coated nanocrystals exhibit photoluminescence having a quantum yield of greater than about 30%.

Tuesday, October 24, 2006

US Patent 7125534 - Double Walled Carbon Nanotube Fabrication

http://www.freepatentsonline.com/7125534.pdf

Usually carbon nanotubes are characterized in terms of single walled and multiwalled types. The single walled nanotubes can be conductive or semiconductive depending on their chirality, while multiwalled tubes are conductive. However, their is also some interest in a subcategory of multiwalled tubes which include only two carbon layers. These double walled carbon nanotubes (DWNTs) may be more pristine then large multiwall tubes and more conducive to ballistic electron transport which would produce less heat in electronics applications. This patent from Rice University teaches a method of producing such DWNTs. Claim 1 reads:


1. A method for producing carbon nanotubes comprising: contacting metal catalyst particles in a reaction zone maintained at an elevated temperature with a carbon-containing compound to produce carbon nanotubes, wherein the carbon nanotubes predominately have no more than two walls and wherein at least about 30% of the carbon nanotubes are double-wall carbon nanotubes.

US Patent 7125308 - Electron Emittion Nanotube Formed By Sand Blasting

http://www.freepatentsonline.com/7125308.pdf

Electron emitting nanotubes have many potential applications in flat panel displays, electron beam lithography, vacuum electronics, etc. Conventionally, the nanotubes are grown from catalytic particles on a substrate using CVD methodology. However, CVD is a high temperature process and cheaper manufacturing methods are being sought. This patent teaches deposition of a nanotube paste via inkjet of silkscreening and exposure of the nanotubes used for electron emission by particle bombardment. Claim 1 reads:

1. A method for enhancing field emission properties of a cold cathode by bead blasting a surface of the cold cathode material, wherein the cold cathode material includes carbon nanotubes.

Monday, October 23, 2006

Top Ten Broadest US Patents for Microelectromechanical Systems (MEMS)

The following is based on a review of 2,642 patents related to MEMS and is based on patent breadth which does not necessarily indicate technical or economic value (or validity) of the patents.

1. US Patent 6481570 - Nortel Networks Limited, priority Sept. 29, 2000

Claim 1 - "A packaging atmosphere packaging a MEMS device, the packaging atmosphere selected to have a thermal conductivity exceeding the thermal conductivity of air."

2. US Patent 6441405 - Cavendish Kinetics Limited, priority June 4, 1998

Claim 1 - "A micro-mechanical element comprising: a discrete switching element; and a switching means for applying force to the switching element to move the switching element between two stable positions. "

3. US Patent 6904191 - Xerox, priority March 19, 2003

Claim 1 - "A micro-electro-mechanical system optical switch, comprising: a cantilever beam optical switch associated with a plurality of optical waveguides formed on a flexible cantilever beam for switching optical states. "

4. US Patent 6004912 - Silicon Light Machines, priority June 5, 1998

Claim 1 - "A method of lubricating a micro machine comprising the step of applying a lubricant to the micro machine wherein the lubricant is a compound having a permanent electric dipole moment."

5. US Patent 6433411 - Agere Systems Guardian Corp. and Lucent Technologies Inc. , priority May 22, 2000

Claim 1 - "A micro-electronic machined mechanical (MEMS) assembly comprising a silicon chamber having a silicon base and silicon sidewalls, and a MEMS device mounted on the silicon base within the silicon chamber."

6. US Patent 6707351 - Motorola, priority March 27, 2002

Claim 1 - "A microelectromechanical resonator comprising: a microelectromechanical resonant structure characterized by a mass and one or more selectively doped regions; a vaporizable material for altering the mass of the resonant structure."

7. US Patent 7019955 - Carnegie Mellon University, priority Sept. 13, 1999

Claim 1 - "An acoustic transducer, comprising: a substrate; a micromachined mesh fabricated on said substrate; a layer of material sealing said mesh to form a flexible diaphragm; and electronics connected to said diaphragm."

8. US Patent 7053736 - Teravicta Technologies, Inc., priority Sept. 30, 2002

Claim 1 - "A microelectromechanical device, comprising a beam configured to apply an opening force on a closed switch, wherein the opening force is substantially independent of a force stored in the closed switch."

9. US Patent 6445006 - Advanced Technology Materials, Inc., priority July 27, 1999 (possibly earlier due to CIP)

Claim 1 - " A microelectronic or microelectromechanical device, comprising: a substrate, wherein the substrate includes an oxide layer and an etch stop layer for the oxide layer; and a fiber formed of a carbon-containing material."

10. US Patent 7114397 - General Electric Company, priority March 12, 2004

Claim 1 - "An apparatus, comprising: a substrate defining a plane; a first conducting plate substantially normal to the substrate; and a second conducting plate substantially normal to the substrate and deformable in response to a pressure."

Sunday, October 22, 2006

US Patent 7123826 - Temperature Controlled Pipe Using Nanotubes

http://www.freepatentsonline.com/7123826.pdf

For pipes used to transport oil or gas undersea the ambient environment can become problematic. The low temperatures can lead to freezing of the material to be transported while the high pressures can lead to compression of the tube if the tube is not sufficiently durable. This patent teaches employing nanotube material to form a conductive layer of the tubing to heat such a tube and reduce the problem of freezing.

Claim 1 reads:

1. A flexible pipe configured to convey hydrocarbon fluids in subsea environments, the pipe comprising a tubular member formed of a plastic material, and a plurality of electrical current conductive materials dispersed in the plastic material for increasing the electrical conductivity of the tubular layer, wherein the electrical current conductive materials are carbon nanotubes.

US Patent 7123359 - Optical Devices Using Nanoparticulate Fractal Medium

http://www.freepatentsonline.com/7123359.pdf

Fractals are geometrical structures that exhibit scale invariance such that a part of the structure is representative of the whole structure. Fractals are common in nature and can be found in the structure of snowflakes, trees, coastlines, and various other natural shapes. This patent takes advantage of optical enhancing properties exhibited by nanoparticle aggregates that exhibit fractal properties. Claim 1 reads:

1. A light emitting apparatus comprising: at least one light source; a fractal medium; and a microcavity, wherein said medium is located in the vicinity of said microcavity.

Thursday, October 19, 2006

US Patent 7122791 - Carbon Nanotube Coatings for Mass Spectroscopy Tips

http://www.freepatentsonline.com/7122791.pdf

Mass spectroscopy is a useful technique to characterize biomolecules by ionizing the biomolecules and determining the mass via analysis of the trajectory of the biomolecules in an electric field. Nanotubes, which have favorable electron emission properties, have previously been proposed as the ionization source. While this patent also proposes the use of nanotubes in mass spectroscopy, rather than using the nanotubes as the emission source it uses the hydrophobic properties on nanotube coatings to reduce the effects of ion spray.

Claim 1 reads:

1. A capillary for a mass spectrometry system, comprising: a channel and a tip, at least one of the channel and the tip comprising a coating of a carbon nanotube material that provides a hydrophobic surface.

US Patent 7122461 - Nanofabrication Using Carbon Nanotubes and DNA

http://www.freepatentsonline.com/7122461.pdf

Nanotubes and DNA have separately been proposed as candidates for new forms of nanoelectronics. This patent from Intel combines these materials for facilitating the selective placement of nanotubes on a substrate by functionalizing nanotubes with DNA.

Claim 14 reads:


14. A method to assemble an interconnect, comprising: functionalizing a first end and a second end of a first set of carbon nanotubes with a first set of DNA segments; providing a platform having an individually addressable array of nano-electrodes, the electrodes having a surface with a second set of DNA segments that are complementary to the first set of DNA segments; applying voltages to the electrodes to couple the first end of the carbon nanotubes with the electrodes to form a first layer selectively; coupling a second set of carbon nanotubes having a third set of DNA segments to the second end of the first set of carbon nanotubes to form a second layer; wherein coupling comprises selectively coupling specific nano-materials to the semiconductor device being formed by applying different electrical potentials to individually addressable electrodes and by providing nano-materials of varied lengths and dimensions; repeating a coupling of additional sets of carbon nanotubes to the first and second sets of carbon nanotubes until the interconnect is formed on the platform; detaching the interconnect from the platform; disposing the detached interconnect on a substrate; and plating the interconnect.

Tuesday, October 17, 2006

US Patent 7122165 - Ozone Functionalization of Nanotube Sidewall

http://www.freepatentsonline.com/7122165.pdf

Oxygen based functioalizaton of carbon nanotubes has been found useful for purposes of purification. However, usually the oxygen moiety attach to the endcaps or defect locations of the nanotubes. This patent discloses methodology to cover the sidewalls of nanotubes as well leading to more robust nanotube purification.

Claim 1 reads:

1. An ozonized carbon nanotube wherein about 3% to 30% of the sidewall carbon atoms have a primary ozonide attached.

US Patent 7121474 - Optically Readable Nanocrystal Memory

http://www.freepatentsonline.com/7121474.pdf

There is much interest in interfacing electronic and optical devices to optimize the advantages of optical circuits (e.g. high bandwidth, no heat generation) with the advantages of electrical circuits (e.g. well established fabrication, high density integration) This patent proposes such a hybrid system that includes a nancrystal electrical memory readable via optical detection.
Claim 1 reads:

1. A method of reading a memory device, comprising: directing a beam of first photons onto an array of insulated nanocrystals formed proximate to a substrate; and sensing an optical response to the beam of the first photons from the array of insulated nanocrystals to determine whether the memory device is in one of a first logic state or a second logic state, wherein the first photons have an energetic level equal to at least a band gap energy between a valence band and a conduction band of the insulated nanocrystals and wherein the optical response includes second photons emitted from the insulated nanocrystals, an absence of a threshold amount of the second photons indicating that the memory device is in the first logic state, a presence of at least the threshold amount of the second photons indicating that the memory device is in the second logic state.

Sunday, October 15, 2006

US Patent 7120047 - Nanotube Ribbon Selector Circuit

http://www.freepatentsonline.com/7120047.pdf

Nanotube-based electronics is one of the most active areas of nanotechnology patenting in the U.S. and Nantero is quickly becoming the dominant player within this area. Nantero's devices focus on the use of arrays of nanotube ribbons and this patent focuses on addressing of the nanotube ribbons. Claim 1 reads:

1. A selection system, comprising: a set of devices; a selector circuit to select at least one of the devices for access, the selector circuit comprising switches, each switch having a nanotube ribbon switching element.

US Patent 7119357 - Nanotube Multi-level Memory

http://www.freepatentsonline.com/7119357.pdf

Kia Silverbrook is an Australian inventor who use to work for Canon in inkjet printing technology. Since that time Silverbrook has begun his own company and has developed an impressive patent portfolio in MEMS-based technologies. In addition, it appears as if Mr.Silverbrook has some interest to nanotube-based electronics. This patent with priority back to 1999 teaches forming 3D memory structures from intersecting nanotubes. Claim 1 reads:

1. A multi-level memory structure comprising the junction of a series of metallic type nanotube structures attached to a semiconductive nanotube so that electrons are substantially captured in said junction.

Thursday, October 12, 2006

US Patent 7118693 - Nanotube EMI Shielding (>10dB)

http://www.freepatentsonline.com/7118693.pdf

Due to the various environments in which electronic circuits are required to operate there is a great interest in materials capable of providing protection from electric shock and interference. Several patents have already been issued toward the use of fullerenes and nanotubes toward this purpose. This patent provides enhanced EMI dissipation (>10dB) using a single or double walled nanotube composite film. Claim 1 reads:

1. A conformal coating that provides EMI shielding, wherein said coating comprises: an insulating layer; and a conductive layer wherein said conductive layer comprises an electrically conductive material and said electrically conductive material comprises carbon nanotubes having an outer diameter of 3.5 nm or less, wherein the EMI shielding is at least 10 dB.

US Patent 7118611 - Dual Nanoparticles for Hydrogen Storage

http://www.freepatentsonline.com/7118611.pdf

Hydrogen fuel cells require materials capable of storing hydrogen efficiently. Fullerenes and carbon nanotubes have already been experimented with as candidate materials for such storage and this patent exploits the high surface to volume ratio of nanoparticle mixtures to achieve hydrogen storage. Claim 1 reads:

1. A material for storing hydrogen as a hydride, wherein the material comprises: a physical mixture of a plurality of non-graphitic first nanoparticles capable of storing hydrogen as a hydride, having an average diameter of about 2 nm to about 200 nm; and a plurality of second nanoparticles, wherein the second nanoparticles are essentially all different from the first nanoparticles by at least one member selected from the group consisting of chemistry structure, average shape, average size, crystallinity, coating, aggregation, and combinations thereof, the second nanoparticle has an average critical dimension of about 200 to about 950 nanometers, and the second particle is capable of storing hydrogen as a hydride.

Monday, October 09, 2006

Top Ten Broadest US Patents for Electrical Applications of Nanotechnology

The following is based on a review of 880 US patents classified by the USPTO as related to electrical applications of nanotechnology. The listed patents are based on the claim breadth and are not necessarily indicative of technical importance or economic value.

1. US Patent 6818821 - Hitachi, priority - Feb.15, 2002

Claim 1 - " Electromagnetic wave absorption material comprising a multi-layer hollow globule of carbon."

2. Reissued US Patent RE 38561 - Till Keesman, priority - Aug. 23, 1996

Claim 10 - "A field emission cathode comprising an electron-emitting part of the cathode formed at least in part as a carbon nano-cylinder."

3. US Patent 6928042 - Hewlett Packard, priority - July 6, 2001

Claim 1 - "A data storage device comprising an array of nanotubes as electron sources; and a phase-change storage layer proximate tips of the electron sources."

4. US Patent 6969504 - Rice University, priority - Sept. 8, 1995

Claim 1 - "An electrical conductor comprising single-wall carbon nanotubes, wherein at least 10% of the single-wall carbon nanotubes in the electrical conductor are armchair single-wall carbon nanotubes."

5. US Patent 6921575 - Fuji Xerox, priority - May 21, 2001

Claim 1 - "A device, which comprises two or more carbon nanotube structure layers comprising carbon nanotube structures in which a network is formed by plural carbon nanotubes intercrossed."

6. US Patent 6239547 - Ise Electronics Corporation, priority - Sept. 30, 1997

Claim 1 - "An electron-emitting source comprising: a carbon nanotube formed from a columnar graphite layer formed from a multilayer graphite column whose tip is open. "

7. US Patent 6798127 - Nano Proprietary, Inc., priority - Oct. 9, 2002

Claim 1 - "A field emission cathode comprising: a) a substrate; and b) a field emission cathode material comprising a mixture of carbon nanotubes and particles. "

8. US Patent 6486597 - N.V. Bekaert S.A., priority - May 9, 1997

Claim 1 - "An electrical device comprising a substrate and coating, said coating comprising carbon and silicon, and having a secondary electron emission coefficient less than about one."

9. US Patent 6919730 - Honeywell International, Inc., priority - Mar. 18, 2002

Claim 1 - "An IR sensor comprising: a plurality of carbon nanotubes; and a temperature sensor positioned proximate the nanotubes for detecting heating caused by IR radiation falling on the nanotubes."

10. US Patent 5260957 - The Charles Stark Draper Laboratory, Inc., priority-Oct. 29, 1992

Claim 1 - "A quantum dot laser comprising: a laser host material; a plurality of quantum dots disposed in said host material; and a pumping source for exciting a population inversion in said quantum dots."

Sunday, October 08, 2006

US Patent 7117454 - Molecular AC Logic Gates

http://www.freepatentsonline.com/7117454.pdf

Hewlett-Packard is leading the way in molecular electronics by creating an enabling platform for the creation of complex molecular logic devices. This patent uses AC signals to enhance the detection of DC logic in a molecular logic system. Claim 1 reads:

1. A nanoscale logic gate comprising: an alternating-current source; two or more input signal lines connected through resistive elements to the alternating-current source and carrying direct-current logical states; a signal line connected to the alternating-current source and two or more input signal lines through a switch element that is either in a high-impedance state or a low-impedance state; and an output signal line that outputs an AC logical state.

US Patent 7116546 - Nanofiber Electrode

Every now and then I see a patent issue with claims that are so improper that I think everyone involved in the patent's issuance should be eliminated from the patent system altogether. I really think that there is a serious failure in accountability for both patent attorneys and patent examiners and while I usually wouldn't mention any names, the claims of this patent have reached a new low. So listed below are the two individuals responsible for the quality of this so-called "patent" and the first claim of the patent.

Attorney:
Andrew L. Filler (Reg. No. 44,107)

Examiner:
Nguyen T. Ha


1. An electrode comprising a first surface including a plurality of nanofibers, wherein a density of the plurality of nanofibers ranges from about 0.11 nanofiber per square micron or less to at least about 1000 nanofibers per square micron, from about 1 nanofiber per square micron or less to at least about 500 nanofibers per square micron, from about 10 nanofibers per square micron or less to at least about 250 nanofibers per square micron, or from about 50 nanofibers per square micron or less to at least about 100 nanofibers per square micron.

Noted problems with the above claim -

1) 35 USC 112 2nd para. - Narrow and broader ranges in the same claim. See MPEP 2173.05(c)

2) 35 USC 102(b) - the claim cites numerous different ranges in the alternative, each of which cites "or less" in referring to the density of nanofibers, which can broadly be read as none. But even ignoring this flaw the specification teaches that carbon nanotubes are a candidate for the claimed nanofibers and arrays of nanotubes have been known far earlier than the earliest priority date (March 18, 2004) of this patent. For example, Agere Systems has US 6,283,812 (see column 12, lines 15-32) and there are numerous other prior art examples in the scientific and patent literature of nanofiber arrays on electrodes.

While I do think that the Examiner responsible for issuance of this patent should be fired (or at least severely reprimanded and have his signatory authority revoked) I also think that Nantero (the company that owns this patent) should really consider new attorneys. This is not the first time I have seen obviously bad patent claims issue from them and it is quite possible that improper practice by their patent attorneys may screw up a company which otherwise seems to be producing interesting ideas in nanoelectronics.

US Patent 7116273 - Microwave Antenna Using Nanotubes

http://www.freepatentsonline.com/7116273.pdf

Use of fractal based geometries for antenna design have led to increased efficiency. However, the bandwidth is limited due to the minimum size of the elements used in the fractal antenna. This patent proposes a 3D network of carbon nanotubes to help improve the bandwidth of such antennas. Claim 1 reads:

1. A microwave antenna comprising: a substrate; an antenna element which is supported on a surface of the substrate and includes a carbon nanotube structure constituting a network structure having a plurality of carbon nanotubes electrically connected to each other; and a power feeding electrode connected to the antenna element.

Thursday, October 05, 2006

US Patents 7115901 and 7115960 - Electromechanical Nanotube FETs

http://www.freepatentsonline.com/7115901.pdf
http://www.freepatentsonline.com/7115960.pdf

Nantero is a company that is making great strides in nanotube-based electronics and is arguably the world leader in the field. Their technology uses nanotubes as electromechanical switches and provides such benefits as resistance to electrostatic shock and reconfigurable electronic architectures. While initially exploited in memory devices, these two recent patents seem fairly fundamental to this technology with applications outside of memory and should place the company on good footing for such new applications.

Claim 1 of US 7115901:

1. A non-volatile field effect device, comprising: a source, drain and gate with a field-modulatable channel between the source and drain, each of the source, drain, and gate having a corresponding terminal; an electromechanically-deflectable, nanotube switching element electrically positioned between one of the source, drain and gate and its corresponding terminal, the others of said source, drain and gate being directly connected to their corresponding terminals; wherein the nanotube switching element is electromechanically-deflectable in response to electrical stimulation at two control terminals to create one of a non-volatile open and non-volatile closed electrical communication state between the one of the source, drain and gate and its corresponding terminal.

Claim 1 of US 7115960:

1. A switching element, comprising an input node; an output node; a nanotube channel element having at least one electrically conductive nanotube; a control electrode disposed in relation to the nanotube channel element to form an electrically conductive channel between said input node and said output node, wherein said channel at least includes said nanotube channel element; and wherein said output node is constructed and arranged so that channel formation is substantially unaffected by the electrical state of the output node.

Tuesday, October 03, 2006

US Patent 7115864 - SWNT Purification Using Heating Under Oxidizing Conditions

http://www.freepatentsonline.com/7115864.pdf

During fabrication procedures of single walled nanotubes often amorphous carbon particles will be formed among an aggregation of the nanotubes. This patent from Smalley's group at Rice (with priority all the back to 1996) claims a basic method of purifying the nanotubes. Claim 1 reads:

1. A method for purifying single-wall carbon nanotubes comprising: a) providing a mixture containing single-wall carbon nanotubes and at least one other reaction product formed in a method for producing single-wall carbon nanotubes; b) heating the mixture under oxidizing conditions; and c) recovering a purified product having a higher concentration of single wall carbon nanotubes than the mixture.

US Patent 7114397 - MEMS Parallel Plate Pressure Sensor

http://www.freepatentsonline.com/7114397.pdf

Parallel plate capacitive sensors are commonly employed to MEMS sensors to detect changes in pressure or as motion sensors. As the displacement between the plates changes due to pressure or motion, the capacitance formed by the plates also changes. This patent teaches forming such a pressure sensor so that it may fit in a smaller area by forming the capacitive plates perpendicular to a base substrate, rather than in parallel to the substrate which is more typical. Claim 1 reads:

1. An apparatus, comprising: a substrate defining a plane; a first conducting plate substantially normal to the substrate; and a second conducting plate substantially normal to the substrate and deformable in response to a pressure.

Speaking as a registered patent agent (and former patent examiner), I find claims such as the above kind of disturbing. On the one hand, given the full context and advantages of the invention (i.e. a MEMS sensors requiring less substrate area) and given the difficulty of fabrication of vertical plates on a substrate, I can see why the invention may be patent worthy. However, the attorney or agent who drafted the above claim clearly did not phrase the claim in such a context and instead opted for a much broader scope. In my opinion, this is bad practice and a failure of common sense on the part of the attorney/agent leading to a claim that is begging to be invalidated or ridiculed for undue breadth. I mean c'mon. Two metal plates held perpendicular to a support. I don't know whether to laugh or cry.

Monday, October 02, 2006

Top Ten Broadest US Patents in Biological Applications of Nanotechnology

The following patents are based on a review of 805 patents classified by the U.S. patent office as involved in biological or medical applications of nanotechnology (class 977, subclasses 904-931). The results are based on claim breadth and are not necessarily indicative of technological or economic importance.

1. U.S. Patent 6,541,617 - Clinical Micro Sensors, Inc. (priority October 27, 1998)

Claim 1 - "A colloid particle comprising at least one covalently attached electron transfer moiety (ETM)."

2. U.S. Patent 5,310,669 - The Trustees of Dartmouth College (priority June 22, 1992)

Claim 1 - "A substrate comprising a fullerene-coated surface having a biological substance attached to the fullerene-coated surface."

3. U.S. Patent 5,972,720 - Roche Diagnostics GmbH (priority June 5, 1996)

Claim 1 - "Colloidal particles to the surface of which are co-adsorbed: 1) biomolecules and 2) polyethylene glycol substituted by thiol and/or disulfide groups."

4. U.S. Patent 6,397,102 - CeramOptec Industries, Inc. (priority Sept. 18, 1998)

Claim 1 - "A photoactivatible drug delivery system comprising: a photoactivatible fullerene molecule containing a photosensitive element within its structure; and a drug compound is complexed with said photoactivatible fullerene molecule."

5. U.S. Patent 6,180,389 - The Research and Development Institute, Inc. (priority Jan. 3, 1997)

Claim 1 - "A virion-constrained nanoparticle comprising a plant virion coat protein shell surrounding a nanopartice of non-viral origin selected from the group consisting of organic, inorganic and organo- metallic materials."

6. U.S. Patent 6,403,653 - The United States of America as represented by the Secretary of the Army and Nanoscale Materials, Inc. (priority June 2, 2000)

Claim 1 - "A topical skin protectant formulation for neutralizing chemical warfare agents into less toxic products comprising: a barrier base cream; and one or more metal oxide reactive nanoparticles as an active moiety."

7. U.S. Patent 6,379,683 - L'Oreal (priority - March 2, 1999)

Claim 1 - "Nanocapsules comprising a lipid core forming or containing a lipophilic active principle, and a water-insoluble continuous polymeric envelope, wherein said polymeric envelope comprises at least one dendritic polyester polymer which contains terminal hydroxyl groups."

8. U.S. Patent 6,544,732 - Illumina, Inc. (priority - May 20, 1999)

Claim 1 - "A composition comprising: a) a substrate with a surface comprising discrete sites, wherein said discrete sites are wells; and b) a population of microspheres randomly distributed on said discrete sites, wherein at least one of said microspheres comprises a nanocrystal."

9. U.S. Patent 6,254,890 - Massachusetts Institute of Technology (priority - Dec. 12, 1997)

Claim 1 - "A method for the delivery of nucleic acids comprising: forming nucleic acid containing nanospheres, wherein said nanospheres are sub-150 nm polymer spheres of which at least 50% of the size distribution of nanospheres is sub-100 nm; and releasing said nucleic acids from said nanospheres over a period of time."

10. U.S. Patent 5,993,856 - FemmePharma (priority - Jan. 15, 1997)

Claim 1 - "A micro or nanoparticulate drug formulation for local or regional topical administration of an effective amount to provide relief from symptoms associated with a disease or disorder in a region in patients in need thereof, wherein the effective amount is less than the effective amount when the drug is administered systemically."

Next week - Top Ten Broadest U.S. Patents for Electronics Applications of Nanotechnology