Patents by Inventor Weitung Wang

Weitung Wang 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).

  • Patent number: 7338624
    Abstract: A method of producing a green form for use in manufacturing a composite, ceramic ion transport membrane is provided in which first and second ceramic powder mixtures are used to produce first and second layers of the green form. The first and second ceramic powder mixtures have ceramic particles and a pore former. After formation of each of the first and second layers or after formation of the second layer, heat is applied to burn out the binder and form pores. This heating is completed prior to application of a dense layer to prevent production of defects within the dense layer. The dense layer contains an ion transport material. Defects are also prevented by grading particle size from the first layer to the dense layer. This allows the second intermediate layer to fill in larger pores of the first layer and to present a smooth surface to the dense layer. Additionally, the second ceramic powder mixture contains in part material used in forming the dense layer for thermal expansion compatibility purposes.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: March 4, 2008
    Assignee: Praxair Technology Inc.
    Inventors: Hancun Chen, Jack C. Chen, Weitung Wang
  • Patent number: 7234224
    Abstract: A method is provided for forming grooves in a polishing pad useful for planarizing a substrate in a chemical mechanical planarization process. The method maintains average velocity as a function of bit diameter to enable groove formation using a rotating bit, whereby grooves can be formed at a higher rate while maintaining high groove quality and low defectivity.
    Type: Grant
    Filed: November 3, 2006
    Date of Patent: June 26, 2007
    Assignee: Rohm and Haas Electronic Materials CMP Holdings, Inc.
    Inventors: Steven Naugler, Steven J. Pufka, Jeffrey R. Stack, Weitung Wang
  • Patent number: 7195794
    Abstract: A method of making an electrolytic cell in which an electrolyte layer of an intermediate sintered form is coated with a pre-coat layer containing electrically non-conductive particles of less than about one-tenth of a micron in size to fill in defects existing within the electrolyte layer. The pre-coat layer is removed so that the electrically non-conductive particles remain within the defects of the electrolyte layer. The cathode layer is then applied to the electrolyte layer with the electrically non-conductive particles in place within the defects. The intermediate sintered form is fired with the applied cathode layer to produce the electrolytic cell.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: March 27, 2007
    Assignee: Praxair Technology, Inc.
    Inventors: Hancun Chen, Weitung Wang
  • Publication number: 20070034614
    Abstract: The present invention provides a method of forming a polishing pad for chemical mechanical planarization utilizing laser ablation. In particular, the method includes providing a laser to cut a groove into the polishing pad and providing a beam splitter to split a laser beam from the laser. Further, the method provides splitting the beam from the laser to provide multiple laser beams onto the polishing pad and wherein the multiple laser beams have effective cutting areas that at least overlap each other.
    Type: Application
    Filed: July 25, 2006
    Publication date: February 15, 2007
    Inventors: Harry McClain, Alan Saikin, Jeffrey Stack, Weitung Wang
  • Publication number: 20050244573
    Abstract: A method of making an electrolytic cell in which an electrolyte layer of an intermediate sintered form is coated with a pre-coat layer containing electrically non-conductive particles of less than about one-tenth of a micron in size to fill in defects existing within the electrolyte layer. The pre-coat layer is removed so that the electrically non-conductive particles remain within the defects of the electrolyte layer. The cathode layer is then applied to the electrolyte layer with the electrically non-conductive particles in place within the defects. The intermediate sintered form is fired with the applied cathode layer to produce the electrolytic cell.
    Type: Application
    Filed: April 30, 2004
    Publication date: November 3, 2005
    Inventors: Hancun Chen, Weitung Wang
  • Patent number: 6858045
    Abstract: A method of manufacturing an electrolytic cell in which an intermediate sintered form is produced that comprises a porous anode layer and an electrolyte layer having a prespecified shape of the electrolytic cell. The electrolyte layer has defects extending through the electrolyte layer. A substance by way of a pressure, a solvent, particle suspended in a solvent or particles introduced by way of thermal spray are introduced into defects within the electrolyte layer. Thereafter, a green cathode layer is applied to the electrolyte layer while the substance is in place, within the defects. The intermediate sintered form with the applied green cathode layer is then fired to produce the electrolytic cell.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: February 22, 2005
    Assignee: Praxair Technology, Inc.
    Inventors: Hancun Chen, Weitung Wang
  • Patent number: 6852204
    Abstract: A wall construction for an electrolytic cell to separate oxygen from an oxygen containing gas in which an electrolyte layer of less than 200 microns and a cathode layer of less than 500 microns are supported by an anode that can have a sufficient thickness to also contain the separated oxygen at pressure. The cathode is formed from the same material as the electrolyte and also a noble metal or noble metal alloy and a mixed conductor. The cathode contains a sufficient amount of the noble metal or noble metal allow and the mixed conductor that the total resistance thereof is not greater than about 70 percent of the total resistance of the anode and the cathode. In a preferred embodiment, first and second porous interfacial layers are situated between an anode layer and the electrolyte and the electrolyte and a cathode layer, respectively.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: February 8, 2005
    Assignee: Praxair Technology, Inc.
    Inventors: Weitung Wang, Hancun Chen, Jack C. Chen
  • Publication number: 20040104519
    Abstract: A method of manufacturing an electrolytic cell in which an intermediate sintered form is produced that comprises a porous anode layer and an electrolyte layer having a prespecified shape of the electrolytic cell. The electrolyte layer has defects extending through the electrolyte layer. A substance by way of a pressure, a solvent, particle suspended in a solvent or particles introduced by way of thermal spray are introduced into defects within the electrolyte layer. Thereafter, a green cathode layer is applied to the electrolyte layer while the substance is in place, within the defects. The intermediate sintered form with the applied green cathode layer is then fired to produce the electrolytic cell.
    Type: Application
    Filed: November 29, 2002
    Publication date: June 3, 2004
    Inventors: Hancun Chen, Weitung Wang
  • Publication number: 20040020766
    Abstract: A wall construction for an electrolytic cell to separate oxygen from an oxygen containing gas in which an electrolyte layer of less than 200 microns and a cathode layer of less than 500 microns are supported by an anode that can have a sufficient thickness to also contain the separated oxygen at pressure. The cathode is formed from the same material as the electrolyte and also a noble metal or noble metal alloy and a mixed conductor. The cathode contains a sufficient amount of the noble metal or noble metal allow and the mixed conductor that the total resistance thereof is not greater than about 70 percent of the total resistance of the anode and the cathode. In a preferred embodiment, first and second porous interfacial layers are situated between an anode layer and the electrolyte and the electrolyte and a cathode layer, respectively.
    Type: Application
    Filed: July 31, 2002
    Publication date: February 5, 2004
    Inventors: Weitung Wang, Hancun Chen, Jack C. Chen
  • Publication number: 20040021240
    Abstract: A method of producing a green form for use in manufacturing a composite, ceramic ion transport membrane is provided in which first and second ceramic powder mixtures are used to produce first and second layers of the green form. The first and second ceramic powder mixtures have ceramic particles and a pore former. After formation of each of the first and second layers or after formation of the second layer, heat is applied to burn out the binder and form pores. This heating is completed prior to application of a dense layer to prevent production of defects within the dense layer. The dense layer contains an ion transport material. Defects are also prevented by grading particle size from the first layer to the dense layer. This allows the second intermediate layer to fill in larger pores of the first layer and to present a smooth surface to the dense layer. Additionally, the second ceramic powder mixture contains in part material used in forming the dense layer for thermal expansion compatibility purposes.
    Type: Application
    Filed: July 31, 2002
    Publication date: February 5, 2004
    Inventors: Hancun Chen, Jack C. Chen, Weitung Wang
  • Patent number: 6264811
    Abstract: The present invention provides an ion conducting ceramic membrane selectively permeable to a gas, for instance oxygen and a method of treating such a membrane to improve permeation through the membrane. The membrane is formed by a mass of a substance through which ions of the gas migrate. The mass has two opposed surfaces where dissociation and ionization of the gas occurs and gas ions release electrons and recombine to form molecules of the gas, respectively. At least one of said two opposed surfaces is treated by a removal of surface material to produce surface irregularities of increased area and therefore an increase in total surface area of a treated surface to in turn increase permeation of the gas. Preferably, both surfaces of the membrane are treated by chemical etching techniques, although sand blasting and ion etching are other possible surface treatments in accordance with the present invention.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: July 24, 2001
    Assignees: Praxair Technology, Inc., BP Amoco Corporation
    Inventors: Weitung Wang, Jack C. Chen, Prasad Apte, Terry Joseph Mazanec