Patents by Inventor Akinobu Tanaka

Akinobu Tanaka 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: 5356753
    Abstract: A positive resists material for high energy-sensitive positive resists which can be developed in aqueous alkali solution, said material comprising (A) a polyhydroxystyrene resin wherein some hydroxyl groups are substituted by t-butoxycarbonyloxy groups, (B) a solution blocking agent, and (C) an onium salt, and being characterized in that said solution blocking agent contains at least one t-butoxycarbonyloxy group per molecule, said onium salt is bis(p-t-butylphenyl) iodinium trifluormethylsulfonate represented by the following formula (1): ##STR1## and the weight proportions of (A), (B), (C) are given by the relations: 0.07.ltoreq.B-.ltoreq.0.40, 0.005.ltoreq.C.ltoreq.0.15, 0.55.ltoreq.A, A+B+C=1. As the resist has low absorption at the exposure wavelength of a KrF exima laser, a fine pattern having vertical walls is easily formed.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: October 18, 1994
    Assignees: Shin-Etsu Chemical Co., Ltd., Nippon Telegraph and Telephone Corp.
    Inventors: Motoyuki Yamada, Osamu Watanabe, Akinobu Tanaka, Hiroshi Ban, Yoshio Kawai
  • Patent number: 5290899
    Abstract: A silicon-containing polymer comprising repeating units of silicon-containing cyclic compound, represented by a general formula (I) ##STR1## (wherein m and n are zero or a positive integer, respectively, however m+n>0, and X is any of an alkyl group, alkoxy group, phenyl group, naphthyl group, substituted phenyl group and substituted naphthyl group or a mixture of these, and the substituent of said substituted phenyl group or substituted naphthyl group indicates any of halogen atom, halogenated alkyl group, amino group, aminoalkyl group and nitro group or a mixture of these), and a photosensitive material containing said silicon-containing polymer are disclosed.
    Type: Grant
    Filed: September 28, 1992
    Date of Patent: March 1, 1994
    Assignees: Tosoh Corporation, Nippon Telegraph and Telephone Corporation
    Inventors: Akinobu Tanaka, Masazumi Hasegawa
  • Patent number: 5158854
    Abstract: Present invention provides a photosensitive and high energy beam sensitive resin composition which may be used as a resist material for forming both of the positive and negative patterns. The resin composition comprises: a substituted polysiloxane having the main polysiloxane chain and a substituent hydrophilic group or groups; and a solvent for the substituted polysiloxane. The substituted polysiloxane used in preferred embodiments of the invention are produced by acylating polysiloxanes including polydiphenylsiloxane and polyphenylsilsesquioxane to introduce acyl groups, followed by oxidation of the thus introduced acyl groups to convert them into carboxyl groups or by reducing the thus introduced acyl groups to convert them into alpha-hydroxyalkyl groups. The acyl, carboxyl or alpha-hydroxyalkyl groups are further substituted to obtain substituted polysiloxanes which are soluble in an aqueous alkali.
    Type: Grant
    Filed: August 29, 1990
    Date of Patent: October 27, 1992
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Saburo Imamura, Akinobu Tanaka, Katsuhide Onose
  • Patent number: 5057396
    Abstract: A silicon-containing polymer comprising repeating units of silicon-containing cyclic compound, represented by a general formula (I) ##STR1## (wehrein m and n are positive integers including 0, respectively, however m+n>0, and X is any of alkyl group, alkoxy group, phenyl group, naphthyl group, substituted phenyl group and substituted naphthyl group or a mixture of these, and the substituent of said substituted phenyl group or substituted naphthyl group indicates any of halogen atom, halogenated alkyl group, amino group, aminoalkyl group and nitro group or a mixture of these), and a photosensitive material containing said silicon-containing polymer are disclosed.
    Type: Grant
    Filed: September 21, 1989
    Date of Patent: October 15, 1991
    Assignees: Tosoh Corporation, Nippon Telegraph and Telephone Corporation
    Inventors: Akinobu Tanaka, Masazumi Hasegawa
  • Patent number: 4702990
    Abstract: The present invention provides a photosensitive resin composition used to form a top resist layer of a multilayer resist system, the composition comprising a photosensitive polyphenylsilsesquioxane represented by the following general formula (I) of: ##STR1## wherein X is selected from the group consisting of acryloyloxymethyl, methacryloyloxymethyl, and cinnamoyloxymethyl; and l, m and n are zero or positive integers but l and m do not take the value of zero simultaneously; and a bisazide compound added to act as a cross-linking agent.The photosensitive resin composition has high sensitivity to UV light and excellent resistance to reactive ion etching under oxygen gas (O.sub.2 RIE).
    Type: Grant
    Filed: May 10, 1985
    Date of Patent: October 27, 1987
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Akinobu Tanaka, Masao Morita, Saburo Imamura, Toshiaki Tamamura, Osamu Kogure
  • Patent number: 4564579
    Abstract: A pattern forming material contains a siloxane polymer having the general formula: ##STR1## [wherein R, R' and R" are the same or different and are respectively one member selected from hydrogen, an alkyl group or a phenyl group; X is one member selected from fluorine, chlorine, bromine, iodine and a --CH.sub.2 Y group (wherein Y is one member selected from chlorine, fluorine, bromine, iodine, an acryloyloxy group, a methacryloyloxy group, and a cinnamoyloxy group); and l, m and n are respectively 0 or a positive integer, l and m not being simultaneously 0]. The material has a high sensitivity to high-energy radiation, a high contrast, and an excellent resistance to reactive ion etching under oxygen gas. The material is conveniently used as a negative resist for forming a submicron pattern having a high aspect ratio.
    Type: Grant
    Filed: December 12, 1984
    Date of Patent: January 14, 1986
    Assignee: Nippon Telegraph & Telephone Public Corporation
    Inventors: Masao Morita, Akinobu Tanaka, Saburo Imamura, Toshiaki Tamamura, Osamu Kogure
  • Patent number: 4507384
    Abstract: A pattern forming material contains a siloxane polymer having the general formula: ##STR1## [wherein R, R' and R" are the same or different and are respectively one member selected from hydrogen, an alkyl group or a phenyl group; X is one member selected from fluorine, chlorine, bromine, iodine and a --CH.sub.2 Y group (wherein Y is one member selected from chlorine, fluorine, bromine, iodine, an acryloyloxy group, a methacryloyloxy group, and a cinnamoyloxy group); and l, m and n are respectively 0 or a positive integer, l and m not being simultaneously 0]. The material has a high sensitivity to high-energy radiation, a high contrast, and an excellent resistance to reactive ion etching under oxygen gas. The material is conveniently used as a negative resist for forming a submicron pattern having a high aspect ratio.
    Type: Grant
    Filed: February 15, 1984
    Date of Patent: March 26, 1985
    Assignee: Nippon Telegraph & Telephone Public Corporation
    Inventors: Masao Morita, Akinobu Tanaka, Saburo Imamura, Toshiaki Tamamura, Osamu Kogure
  • Patent number: 4238385
    Abstract: This invention is directed to coating compositions for electrocoating electroconductive substrates for printed circuits comprising a pigment-containing finely divided synthetic resin powder in which the resin comprises an epoxy resin, and the pigment comprises pigments with 2-10 weight parts of finely divided silica, admixed with a water-dilutable cationic resin, and to methods of utilizing the composition for forming an insulating film on an electroconductive substrate.
    Type: Grant
    Filed: August 14, 1979
    Date of Patent: December 9, 1980
    Assignees: Nippon Telegraph and Telephone Public Corporation, Shinto Paint Co., Ltd.
    Inventors: Yasuomi Okado, Ken Nishizaki, Akinobu Tanaka