Patents by Inventor Eiichirou Ishimizu

Eiichirou Ishimizu 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: 9133366
    Abstract: An object is to provide a polishing liquid composition that can provide hydrophilicity to a wafer surface and effectively improve a haze in polishing of wafers for substrates in electronics industry. The present invention is a polishing liquid composition for wafers, comprising: water; silica particles; an alkaline compound; a polyvinyl alcohol; an anion-modified polyvinyl alcohol; and a surfactant, wherein the mass ratio of the anion-modified polyvinyl alcohol to the polyvinyl alcohol is 0.6 to 5.5. The anion-modified polyvinyl alcohol is preferably a polyvinyl alcohol modified with a carboxy group or a sulfonic acid group.
    Type: Grant
    Filed: May 21, 2013
    Date of Patent: September 15, 2015
    Assignee: NISSAN CHEMICAL INDUSTRIES, LTD.
    Inventors: Hiroaki Sakaida, Eiichirou Ishimizu
  • Publication number: 20150123027
    Abstract: An object is to provide a polishing liquid composition that can provide hydrophilicity to a wafer surface and effectively improve a haze in polishing of wafers for substrates in electronics industry. The present invention is a polishing liquid composition for wafers, comprising: water; silica particles; an alkaline compound; a polyvinyl alcohol; an anion-modified polyvinyl alcohol; and a surfactant, wherein the mass ratio of the anion-modified polyvinyl alcohol to the polyvinyl alcohol is 0.6 to 5.5. The anion-modified polyvinyl alcohol is preferably a polyvinyl alcohol modified with a carboxy group or a sulfonic acid group.
    Type: Application
    Filed: May 21, 2013
    Publication date: May 7, 2015
    Inventors: Hiroaki Sakaida, Eiichirou Ishimizu
  • Publication number: 20090127501
    Abstract: The present invention relates to a polishing composition for silicon wafer comprising silica, a basic compound, a polyaminopolycarboxylic acid compound having hydroxy group, and water. The polishing composition can prevent metal contamination by nickel, chromium, iron, copper or the like, particularly copper contamination in polishing of silicon wafer.
    Type: Application
    Filed: May 17, 2006
    Publication date: May 21, 2009
    Applicant: Nissan Chemical Industries, Ltd.
    Inventors: Yoshiyuki Kashima, Masaaki Ohshima, Eiichirou Ishimizu, Naohiko Suemura
  • Publication number: 20080115423
    Abstract: The present invention relates to a polishing composition for silicon wafer comprising silica; a basic compound; at least one compound selected from the group consisting of amino acid derivatives represented by formula (1) wherein R1, R2 and R3 are identical or different one another, C1-12alkylene group that may be substituted by hydroxyl group, carboxyl group, phenyl group or amino group, and formula (2) wherein R4 and R5 are identical or different each other, hydrogen atom, or C1-12alkyl group that may be substituted by hydroxyl group, carboxyl group, phenyl group or amino group, with a proviso that both R4 and R5 are not hydrogen at the same time, and R6 is C1-12alkylene group that may be substituted by hydroxyl group, carboxyl group, phenyl group or amino group, and the salts of the amino acid derivatives; and water. The polishing composition can prevent metal contamination, particularly copper contamination in polishing of silicon wafer.
    Type: Application
    Filed: October 27, 2005
    Publication date: May 22, 2008
    Applicant: NISSAN CHEMICAL INDUSTRIES, LTD.
    Inventors: Yoshiyuki Kashima, Masaaki Ohshima, Eiichirou Ishimizu, Naohiko Suemura