Patents by Inventor Hiroto Yukawa

Hiroto Yukawa 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: 20020028407
    Abstract: Disclosed is a novel positive-working chemical-amplification photoresist composition capable of giving an extremely finely patterned resist layer in the manufacturing process of semiconductor devices. The photoresist composition comprises: (A) 100 parts by weight of a copolymeric resin consisting of from 50 to 85% by moles of (a) hydroxyl group-containing styrene units, from 15 to 35% by moles of (b) styrene units and from 2 to 20% by moles of (c) acrylate or methacrylate ester units each having a solubility-reducing group capable of being eliminated in the presence of an acid; and (B) from 1 to 20 parts by weight of a radiation-sensitive acid-generating agent which is an onium salt containing a fluoroalkyl sulfonate ion having 3 to 10 carbon atoms as the anion such as bis(4-tert-butylphenyl) iodonium nonafluorobutane sulfonate.
    Type: Application
    Filed: August 3, 2001
    Publication date: March 7, 2002
    Inventors: Katsumi Oomori, Hiroto Yukawa, Ryusuke Uchida, Kazufumi Sato
  • Patent number: 6340553
    Abstract: Disclosed is a novel positive-working chemical-amplification photoresist composition used in the photolithographic patterning works in the manufacture of semiconductor devices capable of giving an excellently patterned resist layer with remarkably small film thickness reduction by the development treatment with an aqueous alkaline developer solution in the areas unexposed to patternwise exposure to light. Characteristically, the resinous ingredient in the composition, which is formulated in combination with a radiation-sensitive acid-generating agent and imparted with an increase in the solubility in an alkaline developer solution, is a ternary copolymeric resin consisting of the monomeric units of (a) hydroxystyrene units, (b) styrene units and (c) 1-alkylcyclohexyl (meth)acrylate units each in a specified molar fraction.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: January 22, 2002
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Katsumi Oomori, Hiroto Yukawa, Akiyoshi Yamazaki, Kazuo Tani, Yohei Kinoshita, Tomotaka Yamada
  • Patent number: 6284430
    Abstract: Disclosed is a novel positive-working chemical-amplification photoresist composition capable of giving an extremely finely patterned resist layer in the manufacturing process of semiconductor devices and a method for forming a finely patterned resist layer therewith. The photoresist composition comprises: (A) 100 parts by weight of a copolymeric resin consisting of from 50 to 85% by moles of (a) hydroxyl group-containing styrene units, from 15 to 35% by moles of (b) styrene units and from 2 to 20% by moles of (c) tert-butyl (meth)acrylate units; and (B) from 1 to 20 parts by weight of a radiation-sensitive acid-generating agent which is an onium salt containing a fluoroalkyl sulfonate ion having 1 to 10 carbon atoms as the anion such as diphenyliodonium trifluoromethane sulfonate.
    Type: Grant
    Filed: September 7, 2000
    Date of Patent: September 4, 2001
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Katsumi Oomori, Hiroto Yukawa, Ryusuke Uchida, Kazufumi Sato
  • Patent number: 6255041
    Abstract: Disclosed is a method for forming an extremely finely patterned resist layer on a substrate surface by using a positive-working chemical-amplification photoresist composition in the manufacturing process of semiconductor devices.
    Type: Grant
    Filed: April 14, 1999
    Date of Patent: July 3, 2001
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Katsumi Oomori, Hiroto Yukawa, Ryusuke Uchida, Kazufumi Sato
  • Patent number: 6180313
    Abstract: Disclosed is a poly(disulfonyl diazomethane) compound as a class of novel compounds represented by the general formula R-SO2-C(N2)-SO2&Brketopenst; Z-SO2-C(N2)-SO2&Brketclosest; nR in which the subscript n is 1 to 5, each R is a monovalent hydrocarbon group and Z is a divalent hydrocarbon group. The invention also discloses a chemical-amplification positive-working photoresist composition which comprises the above mentioned poly(disulfonyl diazomethane) compound as the radiation-sensitive acid-generating agent in combination with a film-forming resin capable of being imparted with increased solubility in an aqueous alkaline solution by the interaction with an acid, such as a polyhydroxystyrene resin of which a part of the hydroxyl groups are substituted by acid-dissociable solubility-reducing groups, e.g., tert-butoxycarbonyl groups.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: January 30, 2001
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Hiroto Yukawa, Waki Ohkubo, Kouki Tamura
  • Patent number: 6153733
    Abstract: Disclosed is a poly(disulfonyl diazomethane) compound as a class of novel compounds represented by the general formula ##STR1## in which the subscript n is 1 to 5, each R is a monovalent hydrocarbon group and Z is a divalent hydrocarbon group. The invention also discloses a chemical-amplification positive-working photoresist composition which comprises the above mentioned poly(disulfonyl diazomethane) compound as the radiation-sensitive acid-generating agent in combination with a film-forming resin capable of being imparted with increased solubility in an aqueous alkaline solution by the interaction with an acid, such as a polyhydroxystyrene resin of which a part of the hydroxyl groups are substituted by acid-dissociable solubility-reducing groups, e.g., tert-butoxycarbonyl groups.
    Type: Grant
    Filed: May 13, 1999
    Date of Patent: November 28, 2000
    Assignees: Tokyo Ohka Kogyo Co., Ltd., Daito Chemix Corporation
    Inventors: Hiroto Yukawa, Waki Ohkubo, Kouki Tamura, Toshiharu Shimamaki, Kei Mori