Patents Represented by Attorney Gerald M. Fisher
  • Patent number: 5302826
    Abstract: Method and apparatus for inducing collisional disassociation of isolated ions in a QIT which employs low frequency modulation of the secular frequency of oscillation of the trapped ions so as to permit sufficient frequency coincidence with the fixed frequency tickle generator to induce collisional disassociation.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: April 12, 1994
    Assignee: Varian Associates, Inc.
    Inventor: Gregory J. Wells
  • Patent number: 5302900
    Abstract: Improved NMR sample tube shapes and inserts for standard tubes to shape the sample for greater homogeneity to provide symmetry of liquid sample and tube to a greater distance from the observe region for the same volume of sample as used in the prior art.
    Type: Grant
    Filed: December 23, 1992
    Date of Patent: April 12, 1994
    Assignee: Varian Associates Inc.
    Inventor: Michael D. Cummings
  • Patent number: 5303281
    Abstract: A mammography X-ray tube providing increased X-ray intensity for shortening patient exposure times to eliminate motion artifacts. The cathode design permits superpositioning of electron beam from multiple filaments.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: April 12, 1994
    Assignee: Varian Associates, Inc.
    Inventors: Thomas J. Koller, Robert C. Treseder
  • Patent number: 5300772
    Abstract: A method for improving sensivity of a QIT by overcoming deleterious space charge effects on the collection of higher mass ions in a QIT by rejecting residual air gas ions during ionization and by rejecting other ions during ionization employing a 1/m/z weighting of the amplitude of each secular frequency, where m/z is the mass to charge ratio of the ions.
    Type: Grant
    Filed: July 31, 1992
    Date of Patent: April 5, 1994
    Assignee: Varian Associates, Inc.
    Inventor: Sidney E. Buttrill, Jr.
  • Patent number: 5291017
    Abstract: An ion trap mass spectrometer system providing superposition of an AC dipole and/or monopole field on the quadrupole field to provide one preferential ejection direction.
    Type: Grant
    Filed: January 27, 1993
    Date of Patent: March 1, 1994
    Assignee: Varian Associates, Inc.
    Inventors: Mingda Wang, Edward G. Marquette
  • Patent number: 5281320
    Abstract: Semiconductor wafers having patterns of steps and grooves defining microcircuit elements thereon are coated with metallic film by supporting the wafers individually adjacent a respective ring-shaped sputtering source in stationary relationship thereto. To effectuate such individual wafer processing on a continuous basis and preserve the evacuated argon environment, a vacuum chamber sputter coating apparatus is provided which has a number of work stations therein, at least one of which includes said ring-shaped sputtering source. Also included is a load lock, and an intermittently rotting vertical plate-like wafer carrier means therewithin positioned closely adjacent the chamber entrance, and carrying wafers in turn from the load lock to the work stations. The carrier includes apertures each accepting a wafer therewithin in an upright position, with the wafers edgewise resiliently supported by clip means, without the use of any externally-originating supports such as platens.
    Type: Grant
    Filed: April 4, 1991
    Date of Patent: January 25, 1994
    Assignee: Varian Associates Inc.
    Inventors: Frederick T. Turner, Martin A. Hutchinson, R. Howard Shaw, Lawrence T. Lamont, Jr.
  • Patent number: 5270798
    Abstract: A high-electron mobility transistor or HEMT has a top surface layer between its gate and drain arranged to produce a channel to drain conductance that is close to the ungated channel conductance to lower the output conductance and reduce gate leakage and gate capacitance. The transistor has a high band-gap active layer to produce a 2DEG channel in an adjacent layer, and source, gate and drain electrodes on the active layer. An undoped or lightly doped surface layer in the region between the gate and the drain produces a low conductance for a region of a few hundred .ANG. from the drain-side edge of the gate. This spreads the electric field domain over at least this few hundred .ANG. distance.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: December 14, 1993
    Assignee: Varian Associates, Inc.
    Inventors: Yi-Ching Pao, James S. Harris
  • Patent number: 5266414
    Abstract: An impregnated thermionic cathode includes a porous matrix of sintered tungsten-alloy particles containing less than six percent iridium and/or other platinum-group metal. The pores of the matrix are impregnated with a temporary process impregnant such as molten copper or an organic monomer, and upon solidification is machined to a desired shape. Thereafter the temporary process impregnant is removed, and the matrix pores again infiltrated with a barium oxide such as molten barium aluminate, or other alkaline earth. A thin, iridium-rich surface activating layer, preferably of about 50% iridium, is then applied to the emitting surface. The diffusion of surface activating iridium is substantially blocked; superior emission and lifetime is provided; and the cathode is relatively low cost and easy to fabricate.
    Type: Grant
    Filed: March 18, 1988
    Date of Patent: November 30, 1993
    Assignee: Varian Associates, Inc.
    Inventors: Gerard A. Goeser, Michael C. Green
  • Patent number: 5262727
    Abstract: An NMR probe having RF shield means to confine the RF magnetic field to an axial region having a length less than the length of the coil form.
    Type: Grant
    Filed: February 20, 1992
    Date of Patent: November 16, 1993
    Assignee: Varian Associates, Inc.
    Inventors: Ali Behbin, Michael D. Cummings
  • Patent number: 5238362
    Abstract: A high vacuum pump comprising an in-line connection on a single drive shaft of an axial turbomolecular compressor and a peripheral compressor where the pump provides better than 10.sup.-7 Pascal inlet when exhausting to atmosphere. The peripheral compressor has a two stage optimized Gaede design which encloses the impellers in a shroud reducing the top and bottom volume surrounding the impellers and providing a large separation pressure drop region between stages of said peripheral compressors to reduce axial leakage.
    Type: Grant
    Filed: July 21, 1992
    Date of Patent: August 24, 1993
    Assignee: Varian Associates, Inc.
    Inventors: Fausto Casaro, Luigi Dolcino, Mars Hablanian, Giampaolo Levi
  • Patent number: 5237274
    Abstract: For reduction of noise in proton resonance measurements, high voltage RF capacitors in the NMR probe comprised a fluorinated oil or grease dielectric.
    Type: Grant
    Filed: November 22, 1991
    Date of Patent: August 17, 1993
    Assignee: Varian Associates, Inc.
    Inventor: Ali Behbin
  • Patent number: 5215135
    Abstract: A new type of fuel pellet and method and apparatus for manufacturing. Pellets are cut directly from logs without requiring grinding and extruding. A veneer type lathe and rolls hold a log and the rolls incise the log surface to a depth larger than the veneer cut prior to cut off with the veneer knife so that all three dimensions of the pellet are precisely controlled as well as being clean cuts.
    Type: Grant
    Filed: June 8, 1992
    Date of Patent: June 1, 1993
    Assignee: Gerald M. Fisher
    Inventors: Robert D. Coakley, Gerald M. Fisher
  • Patent number: 5198665
    Abstract: A method for isolating an ion in a QIT (1) employing values from a mass axis calibration chart to establish the maximum DAC value to scan to in order to scan out m(p)-1 and less during ramp up of RF trapping field while applying a specifically selected fixed supplemental frequency applied during said calibration; and employing values from the calibration curve to establish the DAC value to scan out m(p)+1 and greater during ramping down of RF trapping field, while applying a previously determined fixed broadband spectrum to the QIT end caps.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: March 30, 1993
    Assignee: Varian Associates, Inc.
    Inventor: Gregory J. Wells
  • Patent number: 5118200
    Abstract: Remote measurement of temperature of a process chamber provided with a substrate exhibiting a temperature dependent band gap which substrate is illuminated by a source of continuous spectrum light with a spectrum which overlaps the band gap edge of the substrate. The light which exits the substrate is focused by a lens and is picked up by a fiber optic which takes it to a spectrometer where the spectrum is analyzed to ascertain the intensity versus wavelength histograph for exit rays in the wavelength region of the equivalent band gap of the substrate. The wavelength at the point of infection in the region of band gap edge of the substrate in the histograph of the wavelength versus intensity characteristic of exit rays determines the real time substrate temperature from predetermined calibration data which correlates the wavelength at the point of inflection to actual temperature of the substrates.
    Type: Grant
    Filed: June 13, 1990
    Date of Patent: June 2, 1992
    Assignee: Varian Associates, Inc.
    Inventors: Dimitry M. Kirillov, Ronald A. Powell
  • Patent number: 5102626
    Abstract: A matrix modifier of finely-divided metallic palladium dispersed to contact a metal constituent to improve analysis of the constituent during graphite furnace atomic absorption spectroscopy. The palladium interacts with a variety of metals in a sample to increase the vaporization temperatures of the metals. One way of contacting palladium with the metal analyte is to introduce it as a salt in solution with the sample into the graphite furnace along with a surfactant. A finely-divided metallic palladium having high surface area is produced in the furnace by introduction of hydrogen gas, which acts as a reducing agent, to reduce and maintain palladium in its metallic form at an early point in the temperature program, prior to evaporation of the surfactant.
    Type: Grant
    Filed: October 17, 1988
    Date of Patent: April 7, 1992
    Assignee: Varian Associates, Inc.
    Inventor: Lucinda M. Beach
  • Patent number: 5096364
    Abstract: A wafer handler arm conveys a wafer from a horizontal orientation to a vertical orientation for wafer processing. The arm includes a wafer holding member which is rigidly attached to a first shaft. The first shaft is rotatable about its longitudinal axis and the first shaft is rotatable about a second axis perpendicular to the first axis.
    Type: Grant
    Filed: October 11, 1990
    Date of Patent: March 17, 1992
    Assignee: Varian Associates, Inc.
    Inventors: Mark G. Messer, Lawrence R. Stark
  • Patent number: 5038105
    Abstract: A double-tuned circuit is realized from 1/2.lambda..sub.1 transmission lines for connecting a pair of inductors in series at a first frequency and in parallel for a second frequency where said first and second frequencies are in the ratio of a power of two.
    Type: Grant
    Filed: February 9, 1990
    Date of Patent: August 6, 1991
    Assignee: Spectroscopy Imaging Systems Corporation
    Inventors: Robert S. Codrington, Alan R. Rath
  • Patent number: 5023768
    Abstract: A high voltage, high power DC power supply includes a single turn primary winding driven through a resonating capacitor by an AC source having a frequency in excess of about 100 kHz. The primary winding includes a pair of concentric cylindrical metal walls having opposite ends electrically connected to each other. A volume between the walls includes plural secondary winding assemblies, having different axial positions along the walls. Each of the assemblies includes an annular magnetic core surrounding the interior wall, a winding on the core and a voltage doubler rectifier. DC voltages developed across each secondary winding assembly by the rectifier are added together to provide the high voltage, high power output. The power supply energizes an X-ray tube having a grounded anode and a cathode at a DC voltage of approximately -150 kV, with a power requirement of between 15 and 60 kW.
    Type: Grant
    Filed: December 13, 1989
    Date of Patent: June 11, 1991
    Assignee: Varian Associates, Inc.
    Inventor: John C. Collier
  • Patent number: 4981408
    Abstract: A dual track substrate handling and processing system includes an entrance load lock station, an exit load lock station and a plurality of substrate processing stations, all positioned above a transfer vacuum chamber. The load lock station and each processing station are configured to hold two vertically oriented workpieces. A transport system conveys workpieces two at a time from parallel input cassettes to the entrance load lock station. The transport system includes a transport assembly that simultaneously advances two workpieces from each station to the next station; thus workpieces are processed two at a time in the same environment in each processing station and system throughput is correspondingly increased.
    Type: Grant
    Filed: December 18, 1989
    Date of Patent: January 1, 1991
    Assignee: Varian Associates, Inc.
    Inventors: John L. Hughes, Thomas E. Shula, Carlos E. Rodriguez
  • Patent number: 4952814
    Abstract: A microwave electron accelerator has a very limited range over which pulse beam current can be adjusted without destabilizing the operation of the machine. Therefore, means must be devised to reduce current without seriously reducing energy, or producing unwanted x-rays. One means includes spreading the beam in a scattering foil and subsequently absorbing the outer portion with a blocking wall. In order to make the means adjustable the foil thickness, the size of a passing aperture in the blocking wall or the position of the blocking wall can be adjusted.
    Type: Grant
    Filed: June 14, 1989
    Date of Patent: August 28, 1990
    Assignee: Varian Associates, Inc.
    Inventor: Calvin J. Huntzinger