Patents by Inventor Benjamin Y. H. Liu

Benjamin Y. H. Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20110220811
    Abstract: A method and apparatus are disclosed for exposing particles in a gas in order to cause the charge on the particles to change, the apparatus comprising a chamber with an inlet for the gas to enter and an outlet for the gas to exit. The chamber is surrounded by an enclosure with a conductive wall, the wall being held at a ground potential. An electrode with an exposed tip is in contact with the gas in the chamber, the electrode being held at a different potential from the ground potential. The electrode is connected to a source of voltage sufficient to cause a corona discharge to occur forming ions in the chamber, and creating a region of space with a high electric field intensity and another region of space in which the electric field intensity is lower. The inlet and outlet define a gas flow path from the inlet to the outlet such that the gas flow path passes mainly through the region with the lower electric field intensity.
    Type: Application
    Filed: October 12, 2010
    Publication date: September 15, 2011
    Applicant: MSP Corporation
    Inventors: William Dick, Francisco J. Romay, Benjamin Y.H. Liu
  • Publication number: 20110192909
    Abstract: The present disclosure relates to an apparatus and a method for forming a droplet aerosol for vaporization and subsequent thin film deposition on a substrate. The apparatus includes a mechanism to control the rate of liquid flow through the apparatus, the mechanism including a piezoelectric actuator to adjust the rate of liquid flow and an atomizing mechanism drawing gas from a compressed gas source such that when the gas source conjoins with the liquid, the liquid is atomized to form droplets suspended in the gas thereby forming a droplet aerosol suitable for subsequent thin film deposition on a substrate. The method includes drawing a gas from a compressed gas source and drawing a liquid from a liquid source. The liquid and gas are conjoined in either a coaxial flow relationship or a radial flow relationship or an angular relationship between radial and coaxial flow wherein the gas engages the liquid to faun droplets suitable for vaporization and subsequent thin film deposition on a substrate.
    Type: Application
    Filed: February 1, 2011
    Publication date: August 11, 2011
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, Thuc M. Dinh, Yamin Ma
  • Publication number: 20110097507
    Abstract: A method for establishing a calibrating standard for wafer inspection includes depositing solid ionized particles of a known size range with an aerosol onto a wafer. The method also includes depositing particles onto a wafer in a deposition chamber by using an aerosol stream and the solid particles suspended in a gas; ionizing the aerosol stream with a negative or positive charge polarity or both by passing the aerosol stream through a non-radioactive ionizer to produce charged particles and supplying such aerosol stream to the deposition chamber.
    Type: Application
    Filed: January 5, 2011
    Publication date: April 28, 2011
    Applicant: MSP Corporation
    Inventors: William Dick, Benjamin Y.H. Liu
  • Publication number: 20110091649
    Abstract: The present disclosure describes a method and apparatus for detecting particles in a gas by saturating the gas with vapor and causing the gas to flow through a chamber with walls that are at a temperature different than the temperature of the entering gas creating a gas turbulence within the chamber resulting in the gas becoming super-saturated with vapor and causing said super-saturated vapor to condense on said particles and form droplets, which are then detected and counted by an optical light-scattering detector.
    Type: Application
    Filed: August 31, 2010
    Publication date: April 21, 2011
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, Thuc M. Dinh, William D. Dick, Aaron M. Collins, Francisco J. Romay
  • Patent number: 7882799
    Abstract: A method for establishing a calibrating standard for wafer inspection includes depositing solid ionized particles of a known size range with an aerosol onto a wafer. The method also includes depositing particles onto a wafer in a deposition chamber by using an aerosol stream and the solid particles suspended in a gas; ionizing the aerosol stream with a negative or positive charge polarity or both by passing the aerosol stream through a non-radioactive ionizer to produce charged particles and supplying such aerosol stream to the deposition chamber. An apparatus for producing charged particles includes an atomizer and a non-radioactive ionizer in fluid communication with each other. The apparatus may also include an electrospray droplet generator for producing an aerosol with dry-solid particles and an ionizer that ionizes the molecules of the gas.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: February 8, 2011
    Assignee: MSP Corporation
    Inventors: William Dick, Benjamin Y. H. Liu
  • Patent number: 7830510
    Abstract: The present disclosure has an apparatus for detecting fibers in a gas flowing along a passageway. A laser beam is provided at one end of the passageway and the beam is directed along a length of the passageway through which the gas flows. An electrode system, as disclosed, a quadrupole electrode system is mounted along the passageway to cause fibers carried in the gas to oscillate in a detection zone. A photo detector is positioned laterally of the passageway and detects light scattered by the oscillating fibers and projected through an opening in the passageway to provide an output signal that is a function of the light scattered by the fibers in the detection zone.
    Type: Grant
    Filed: February 3, 2009
    Date of Patent: November 9, 2010
    Assignee: MSP Corporation
    Inventors: Benjamin Y. H. Liu, William D. Dick, Francisco J. Romay, Mark J. Battista, Pedro Lilienfeld
  • Publication number: 20100203244
    Abstract: The present invention involves injecting a liquid and gas into a vapor holding chamber held at a sufficiently high temperature to insure all the liquid injected is vaporized and held in the chamber as a vapor. The gas/vapor mixture is then delivered to the deposition chamber in which the deposition substrate is held.
    Type: Application
    Filed: April 19, 2010
    Publication date: August 12, 2010
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, Yamin Ma
  • Publication number: 20100085569
    Abstract: The present disclosure has an apparatus for detecting fibers in a gas flowing along a passageway. A laser beam is provided at one end of the passageway and the beam is directed along a length of the passageway through which the gas flows. An electrode system, as disclosed, a quadrupole electrode system is mounted along the passageway to cause fibers carried in the gas to oscillate in a detection zone. A photo detector is positioned laterally of the passageway and detects light scattered by the oscillating fibers and projected through an opening in the passageway to provide an output signal that is a function of the light scattered by the fibers in the detection zone.
    Type: Application
    Filed: February 3, 2009
    Publication date: April 8, 2010
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, William D. Dick, Francisco J. Romay, Mark Battista
  • Publication number: 20100065972
    Abstract: An apparatus for atomizing a precursor liquid for vapor generation and thin film deposition on a substrate. The precursor liquid is atomized by a carrier gas to form a droplet aerosol comprised of small precursor liquid droplets suspended in the carrier gas. The droplet aerosol is then heated to form vapor, producing a gas/vapor mixture that can be introduced into a deposition chamber to form thin films on a substrate. The liquid is introduced into the atomizing apparatus in such a manner as to avoid excessive heating that can occur or lead to the formation of undesirable by-products due to material degradation as result of thermal decomposition. The apparatus is particularly suited for vaporizing high molecular weight substances with a low vapor pressure that requires a high vaporization temperature for the liquid to vaporize. The apparatus can also be used to vaporize solid precursors dissolved in a solvent for vaporization.
    Type: Application
    Filed: September 11, 2009
    Publication date: March 18, 2010
    Applicant: MSP Corporation
    Inventor: Benjamin Y.H. Liu
  • Publication number: 20090293807
    Abstract: An apparatus removes particles from a gas/vapor mixture while at the same time improves the uniformity of gas/vapor mixture to create a more uniformly-mixed mixture stream for thin film deposition and semiconductor device fabrication.
    Type: Application
    Filed: May 26, 2009
    Publication date: December 3, 2009
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, Yamin Ma, Thuc Dinh
  • Publication number: 20090084315
    Abstract: This disclosure pertains to a method and apparatus to permit changing a filter on the input line to a vacuum deposition chamber without breaking or reducing the vacuum for the deposition chamber and other components in the deposition system. Isolation valves are provided at the inlet and outlet of the filter so the filter can be isolated from the source of vacuum and the deposition chamber for removal and replacement of the filter.
    Type: Application
    Filed: September 22, 2008
    Publication date: April 2, 2009
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, Yamin Ma, Thuc M. Dinh
  • Patent number: 7363828
    Abstract: The present invention includes an apparatus for aerosol measurement having a high concentration of particles the apparatus comprising a diluter for diluting the concentration of particles in a sample aerosol stream to form a diluted aerosol stream, and a sensor for detecting the particles in the diluted aerosol stream by vapor condensation, droplet growth and optical detection. Such apparatus may be housed in a common housing along with the electronics for operating the apparatus and components such as pumps and filters that may be necessary. The diluter includes an input for an aerosol stream having an initial particle concentration, and a dilution stream. The aerosol stream and the dilution stream flow through a restriction which is sized such that turbulent flow is created so that the dilution stream and the aerosol stream are mixed to produce a diluted aerosol stream.
    Type: Grant
    Filed: August 25, 2005
    Date of Patent: April 29, 2008
    Assignee: MSP Corporation
    Inventor: Benjamin Y. H. Liu
  • Patent number: 7325441
    Abstract: A personal mask testing system (PMTS) is of a size of a human hand. The PMTS has several energy efficient features that permit running the PMTS from a battery source within the housing. The PMTS also includes a replaceable vapor source.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: February 5, 2008
    Assignee: MSP Corporation
    Inventors: Benjamin Y. H. Liu, Daryl L. Roberts
  • Patent number: 7276224
    Abstract: Methods of producing nanoporous particles by spray pyrolysis of a precursor composition including a reactive precursor salt and a nonreactive matrix salt are provided, wherein the matrix salt is used as a templating medium. Nanoporous aluminum oxide particles produced by the methods are also provided.
    Type: Grant
    Filed: June 11, 2002
    Date of Patent: October 2, 2007
    Assignee: Regents of the University of Minnesota
    Inventors: Michael R. Zachariah, Benjamin Y. H. Liu
  • Patent number: 7267711
    Abstract: A compact electrostatic precipitator is designed specifically for use in connection with eliminating particles from crankcase emissions of a Diesel engine. Such emissions may carry solid soot particles as well as suspended oil droplets. The electrostatic precipitator has an electrode housing in which a high voltage electrode is mounted, and the emissions from the crankcase of a Diesel engine are passed across the electrode to an outlet. A high voltage power supply is mounted in a separate housing, and the output of the high voltage power supply is connected to the electrode only when the electrode housing and the power supply housing are properly mated, to thereby disable the high voltage connection to the electrode when the power supply housing is removed.
    Type: Grant
    Filed: August 25, 2004
    Date of Patent: September 11, 2007
    Assignee: MSP Corporation
    Inventor: Benjamin Y. H. Liu
  • Patent number: 7082811
    Abstract: A cascade impactor apparatus has a series of vertically stacked impactor housing sections. Each of the impactor housing sections has an upper portion that supports a motor for driving an impactor plate that is positioned below a nozzle through which flow passes. Each housing section also has an outlet passageway leading to a lower impactor chamber for the next in a series of impactor chambers, except the last outlet passageway is coming through a filter to exhaust. The impactor chambers are defined by a skirt that seals on the neck of the next downstream housing section. The impactor plates are each driven by a separate motor, and held onto a hub on the motor output shaft with a magnetic coupling so the plates can be removed when the housings are separated.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: August 1, 2006
    Assignee: MSP Corporation
    Inventors: Virgil A. Marple, Benjamin Y. H. Liu
  • Patent number: 6902604
    Abstract: An electrostatic precipitator, including for a diesel engine electrostatic crankcase ventilation system for blowby gas, includes a corona discharge electrode assembly in a housing, an insulator extending along an internal surface of a wall of the housing, a power supply in the housing on the opposite side of the insulator from the housing wall such that the insulator is between the housing wall and the power supply, and a low voltage lead extending through the housing wall and through the insulator to the power supply, eliminating pass-through of a high voltage lead through the housing wall and through the insulator. The power supply is preferably provided in the hollow interior of the corona discharge electrode assembly.
    Type: Grant
    Filed: May 15, 2003
    Date of Patent: June 7, 2005
    Assignees: Fleetguard, Inc., MSP Corporation
    Inventors: Scott P. Heckel, Gregory Hoverson, Benjamin Y. H. Liu
  • Publication number: 20040250634
    Abstract: A compact cascade impactor is formed to classify particles carried in a flow through the impactor. The impactor has collection chambers that are arranged to conserve space and yet provide a large flow passageway. The collection chamber may be tear drop shaped and being nested together. The impactor includes nozzles that are used across a desired range without.
    Type: Application
    Filed: April 13, 2004
    Publication date: December 16, 2004
    Applicant: MSP Corporation
    Inventors: Benjamin Y.H. Liu, Virgil A. Marple, Daryl L. Roberts
  • Patent number: 6829044
    Abstract: A condensation nucleus counter has a series of flow passageways forming a flow path, including a first passageway for carrying the gas stream having the particles to be detected which is preferably preheated A saturator is positioned to receive the flow of the gas stream and is made of a porous material of a controlled pore size having a portion immersed in a liquid working fluid. The liquid working fluid moves by capillary action along the length of the saturator. Vapor from the working liquid will be transferred to the gas stream as it moves through the saturator. The gas stream then passes to a condenser that reduces the temperature of the gas stream and causes the working fluid vapor to condense on the particles in the gas stream to form droplets that can be detected and counted.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: December 7, 2004
    Assignee: MSP Corporation
    Inventor: Benjamin Y. H. Liu
  • Publication number: 20040226449
    Abstract: An electrostatic precipitator, including for a diesel engine electrostatic crankcase ventilation system for blowby gas, includes a corona discharge electrode assembly in a housing, an insulator extending along an internal surface of a wall of the housing, a power supply in the housing on the opposite side of the insulator from the housing wall such that the insulator is between the housing wall and the power supply, and a low voltage lead extending through the housing wall and through the insulator to the power supply, eliminating pass-through of a high voltage lead through the housing wall and through the insulator. The power supply is preferably provided in the hollow interior of the corona discharge electrode assembly.
    Type: Application
    Filed: May 15, 2003
    Publication date: November 18, 2004
    Inventors: Scott P. Heckel, Gregory Hoverson, Benjamin Y. H. Liu