Patents by Inventor Seksan Dheandhanoo

Seksan Dheandhanoo 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: 20050161060
    Abstract: The present invention is a process for cleaning equipment surfaces in a semiconductor material processing chamber after deposition of a porous film containing a porogen, comprising; contacting the equipment surfaces with a proton donor containing atmosphere to react with the porogen deposited on the equipment surfaces; contacting the equipment surfaces with a fluorine donor containing atmosphere to react with the film deposited on the equipment surfaces.
    Type: Application
    Filed: December 22, 2004
    Publication date: July 28, 2005
    Inventors: Andrew Johnson, Seksan Dheandhanoo, Mark Bitner, Raymond Vrtis
  • Patent number: 6639214
    Abstract: A method for eliminating interference when analyzing a test sample of a bulk inert gas in an ion mobility spectrometer is disclosed which includes the steps of providing an ionization source for the spectrometer to form ions of the bulk inert gas, mixing a reagent gas with the test sample prior to entry into the spectrometer to alter the nature of the ions formed by the bulk inert gas to shift the location of a bulk inert gas mobility peak such that a bulk inert gas mobility peak does not overlap with an impurity mobility peak of the ions of a trace impurity of interest, whereby bulk inert gas ions are quenched and a clusters of the reagent gas and the bulk gas are formed. Alternatively, the reagent gas may be mixed with the drift gas in the ion mobility spectrometer, rather than with the test sample.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: October 28, 2003
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Suhas Narayan Ketkar, Seksan Dheandhanoo
  • Patent number: 6606899
    Abstract: A device for measuring a total concentration of impurities in a sample gas is provided which includes a housing having an inlet to allow the sample gas to enter the housing, an emitter to generate ions from the sample gas, a field gradient to accelerate the ions toward a collector, the collector adapted to measure total ions, and an outlet to allow the sample gas to exit the housing, whereby a change in total ions received by the collector indicates a change in the total concentration of impurities in the sample gas.
    Type: Grant
    Filed: July 7, 2000
    Date of Patent: August 19, 2003
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Suhas Narayan Ketkar, Seksan Dheandhanoo
  • Patent number: 6518581
    Abstract: A gas sampling and inlet device for a mass spectrometer has a hollow housing sleeve with an open inside region and a hollow inner sleeve with an open inside region, with the inner sleeve coaxial to the housing sleeve. One end of the housing sleeve and one end of the inner sleeve are connected with a single first end cap. The second end of the housing sleeve has a second end cap, but the second end of the inner sleeve is open such that the inside of the inner sleeve is open to the inside of the housing sleeve. The first end cap has a small diameter orifice adapted to receive a gaseous fluid. The second end cap is connected to a mass spectrometer. The second end cap has an orifice adapted to receive a gaseous fluid into the mass spectrometer that is substantially smaller in diameter than the orifice in the first end cap. The housing sleeve has a vacuum pump port to allow a vacuum to be created in the interior of the inlet device.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: February 11, 2003
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Seksan Dheandhanoo, Ralph J. Ciotti, Suhas Narayan Ketkar, Richard Vincent Pearce
  • Patent number: 5661225
    Abstract: An apparatus for generating a low concentration calibration gas mixture containing percent, ppm, ppb or ppt amounts of a desired analyte from a high concentration gas mixture and a high purity diluent using a series of source gas containing vessels and a series of parallel gas or chemical conduits controlled by mass flow controllers in a purged enclosure with conduits to purge gas conduits of residual gases or corrosive gases.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: August 26, 1997
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Robert Gordon Ridgeway, Richard Vincent Pearce, Peter James Maroulis, Seksan Dheandhanoo, Suhas Narayan Ketkar