Patents by Inventor Osamu Sekizawa

Osamu Sekizawa 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: 8820122
    Abstract: A titania-doped quartz glass suited as an EUV lithographic member is prepared by feeding a silicon-providing reactant gas and a titanium-providing reactant gas through a burner along with hydrogen and oxygen, subjecting the reactant gases to oxidation or flame hydrolysis to form synthetic silica-titania fine particles, depositing the particles on a rotating target, and concurrently melting and vitrifying the deposited particles to grow an ingot of titania-doped quartz glass. The target is retracted such that the growth front of the ingot may be spaced a distance of at least 250 mm from the burner tip.
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: September 2, 2014
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Shigeru Maida, Hisatoshi Otsuka, Osamu Sekizawa, Naoki Yanagisawa
  • Patent number: 8596095
    Abstract: A synthetic quartz glass ingot is prepared by vapor phase hydrolyzing or oxidatively decomposing a silica feedstock in a flame to form fine particles of silica, depositing the silica particles on a target and melting and vitrifying the particles to form a synthetic quartz glass ingot on the target while the target is moved back and forth. The method further comprises: (i) continuously feeding the silica feedstock at a predetermined rate, (ii) keeping the flame in constant contact with an overall growing face, (iii) cyclically repeating the back and forth movement of the target at a predetermined speed, and (iv) maintaining the shape of the growing ingot unchanged.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: December 3, 2013
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa
  • Publication number: 20120058419
    Abstract: A titania-doped quartz glass suited as an EUV lithographic member is prepared by feeding a silicon-providing reactant gas and a titanium-providing reactant gas through a burner along with hydrogen and oxygen, subjecting the reactant gases to oxidation or flame hydrolysis to form synthetic silica-titania fine particles, depositing the particles on a rotating target, and concurrently melting and vitrifying the deposited particles to grow an ingot of titania-doped quartz glass. The target is retracted such that the growth front of the ingot may be spaced a distance of at least 250 mm from the burner tip.
    Type: Application
    Filed: September 1, 2011
    Publication date: March 8, 2012
    Applicant: SHIN-ETSU CHEMICAL CO., LTD.
    Inventors: Shigeru Maida, Hisatoshi Otsuka, Osamu Sekizawa, Naoki Yanagisawa
  • Patent number: 7954340
    Abstract: When a synthetic quartz glass substrate is prepared from a synthetic quartz glass block, (I) the block has a hydrogen molecule concentration of 5×1017-1×1019 molecules/cm3, (II) the substrate has a hydrogen molecule concentration of 5×1015-5×1017 molecules/cm3, (III) the substrate has an in-plane variation of its internal transmittance at 193.4 nm which is up to 0.2%, and (IV) the substrate has an internal transmittance of at least 99.6% at 193.4 nm. The synthetic quartz glass substrate has a high transmittance and a uniform transmittance distribution, and is adapted for use with excimer lasers, particularly ArF excimer lasers.
    Type: Grant
    Filed: April 2, 2009
    Date of Patent: June 7, 2011
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa
  • Patent number: 7827824
    Abstract: A synthetic quartz glass substrate having (i) an OH concentration of 1-100 ppm and a hydrogen molecule concentration of 1×1016-1×1019 molecules/cm3, (ii) an in-plane variation of its internal transmission at wavelength 193.4 nm which is up to 0.2%, and (iii) an internal transmission of at least 99.6% at wavelength 193.4 nm is suited for use with excimer lasers.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: November 9, 2010
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa
  • Publication number: 20090188281
    Abstract: When a synthetic quartz glass substrate is prepared from a synthetic quartz glass block, (I) the block has a hydrogen molecule concentration of 5×1017-1×1019 molecules/cm3, (II) the substrate has a hydrogen molecule concentration of 5×1015-5×1017 molecules/cm3, (III) the substrate has an in-plane variation of its internal transmittance at 193.4 nm which is up to 0.2%, and (IV) the substrate has an internal transmittance of at least 99.6% at 193.4 nm. The synthetic quartz glass substrate has a high transmittance and a uniform transmittance distribution, and is adapted for use with excimer lasers, particularly ArF excimer lasers.
    Type: Application
    Filed: April 2, 2009
    Publication date: July 30, 2009
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa
  • Publication number: 20080115533
    Abstract: A synthetic quartz glass ingot is prepared by vapor phase hydrolyzing or oxidatively decomposing a silica feedstock in a flame to form fine particles of silica, depositing the silica particles on a target and melting and vitrifying the particles to form a synthetic quartz glass ingot on the target while the target is moved back and forth. The method further comprises: (i) continuously feeding the silica feedstock at a predetermined rate, (ii) keeping the flame in constant contact with an overall growing face, (iii) cyclically repeating the back and forth movement of the target at a predetermined speed, and (iv) maintaining the shape of the growing ingot unchanged.
    Type: Application
    Filed: September 6, 2007
    Publication date: May 22, 2008
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa
  • Publication number: 20080119346
    Abstract: A synthetic quartz glass substrate having (i) an OH concentration of 1-100 ppm and a hydrogen molecule concentration of 1×1016-1×1019 molecules/cm3, (ii) an in-plane variation of its internal transmission at wavelength 193.4 nm which is up to 0.2%, and (iii) an internal transmission of at least 99.6% at wavelength 193.4 nm is suited for use with excimer lasers.
    Type: Application
    Filed: September 6, 2007
    Publication date: May 22, 2008
    Applicant: Shin-Etsu Chemical Co., Ltd.
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa
  • Publication number: 20070049482
    Abstract: When a synthetic quartz glass substrate is prepared from a synthetic quartz glass block, (I) the block has a hydrogen molecule concentration of 5×1017-1×1019 molecules/cm3, (II) the substrate has a hydrogen molecule concentration of 5×1015-5×1017 molecules/cm3, (III) the substrate has an in-plane variation of its internal transmittance at 193.4 nm which is up to 0.2%, and (IV) the substrate has an internal transmittance of at least 99.6% at 193.4 nm. The synthetic quartz glass substrate has a high transmittance and a uniform transmittance distribution, and is adapted for use with excimer lasers, particularly ArF excimer lasers.
    Type: Application
    Filed: August 10, 2006
    Publication date: March 1, 2007
    Inventors: Hisatoshi Otsuka, Kazuo Shirota, Osamu Sekizawa