Patents by Inventor Taku Nakao

Taku Nakao 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: 7402372
    Abstract: A positive resist composition includes a resin (A) that increases alkali solubility due to action of an acid, wherein the resin comprises a copolymer containing a first structural unit (a1) derived from hydroxystyrene, and a second structural unit (a2) derived from a (meth)acrylate with an alcoholic hydroxyl group, and a weight average molecular weight of the copolymer is within a range from 2000 to 8500, and 10 mol % to 25 mol % of a combined total of hydroxyl groups within the structural units (a1) and alcoholic hydroxyl groups within the structural units (a2) are protected with acid dissociable, dissolution inhibiting groups, an acid generator (B) that generates an acid on exposure to light, and polypropylene glycol (C).
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: July 22, 2008
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Mitsuo Hagihara, Taku Nakao, Kazuyuki Nitta
  • Patent number: 7364831
    Abstract: A positive resist composition includes a resin component (A) whose alkaline solubility changes by an action of an acid, an acid generator component (B), and polypropylene glycol, wherein the component (A) includes a resin component (A1) including a constitutional unit (a1) represented by general formula (I), a constitutional unit (a2) represented by general formula (II), and a constitutional unit (a3) having an acid dissociable dissolution inhibiting group, wherein R represents a hydrogen atom or a methyl group, and m represents an integer of 1 to 3, wherein R represents a hydrogen atom or a methyl group, and R1 represents alkyl group having a carbon number of 1 to 5, and l represents an integer of 0 to 3.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: April 29, 2008
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kouji Yonemura, Taku Nakao
  • Patent number: 7094924
    Abstract: Disclosed is a method for decreasing the surface defects of a patterned photoresist layer on a substrate surface obtained by the procedure comprising the steps of (a) forming a photoresist layer of a positive-working chemical-amplification photoresist composition on the substrate surface, (b) patternwise exposing the photoresist layer to actinic rays, (c) subjecting the patternwise-exposed photoresist layer to a post-exposure baking treatment and (d) a development treatment. The improvement can be accomplished by bringing the photoresist layer after the post-exposure baking treatment into contact with an aqueous acidic solution having a pH of 3.5 or lower for 1 to 90 seconds. The acid contained in the aqueous acidic solution is preferably an aromatic sulfonic acid or, more preferably, a diphenyl ether sulfonic acid such as dodecyl(diphenyl ether) disulfonic acids.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: August 22, 2006
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kazuyuki Nitta, Taku Nakao, Satoshi Maemori, Tatsuya Matsumi
  • Publication number: 20060014100
    Abstract: A positive resist composition includes a resin component (A) whose alkaline solubility changes by an action of an acid, an acid generator component (B), and polypropylene glycol, wherein the component (A) includes a resin component (A1) including a constitutional unit (a1) represented by general formula (I), a constitutional unit (a2) represented by general formula (II), and a constitutional unit (a3) having an acid dissociable dissolution inhibiting group, wherein R represents a hydrogen atom or a methyl group, and m represents an integer of 1 to 3, wherein R represents a hydrogen atom or a methyl group, and R1 represents alkyl group having a carbon number of 1 to 5, and 1 represents an integer of 0 to 3.
    Type: Application
    Filed: May 6, 2005
    Publication date: January 19, 2006
    Inventors: Kouji Yonemura, Taku Nakao
  • Publication number: 20050042541
    Abstract: A positive resist composition includes a resin (A) that increases alkali solubility due to action of an acid, wherein the resin comprises a copolymer containing a first structural unit (a1) derived from hydroxystyrene, and a second structural unit (a2) derived from a (meth)acrylate with an alcoholic hydroxyl group, and a weight average molecular weight of the copolymer is within a range from 2000 to 8500, and 10 mol % to 25 mol % of a combined total of hydroxyl groups within the structural units (a1) and alcoholic hydroxyl groups within the structural units (a2) are protected with acid dissociable, dissolution inhibiting groups, an acid generator (B) that generates an acid on exposure to light, and polypropylene glycol (C).
    Type: Application
    Filed: June 10, 2004
    Publication date: February 24, 2005
    Inventors: Mitsuo Hagihara, Taku Nakao, Kazuyuki Nitta
  • Publication number: 20040072103
    Abstract: Disclosed is a novel chemical-amplification positive-working photoresist composition capable of giving a patterned resist layer with excellent properties such as photosensitivy, pattern resolution, heat resistance and cross sectional profile of the patterned resist layer. The composition is characterized by the use of, as the film-forming resinous component, a hydroxyl-containing resinous ingredient which is a combination of a first resin of which from 30 to 60% of the hydroxyl groups are substituted by acid-dissociable solubility-reducing groups and a second resin of which from 5 to 20% of the hydroxyl groups are substituted by acid-dissociable groups of the same kind as in the first resin in a weight proportion of 1.9 to 9:1.
    Type: Application
    Filed: November 20, 2003
    Publication date: April 15, 2004
    Inventors: Kazufumi Sato, Satoshi Maemori, Taku Nakao, Kazuyuki Nitta
  • Patent number: 6677103
    Abstract: Disclosed is a novel chemical-amplification positive-working photoresist composition capable of giving a patterned resist layer with excellent properties such as photosensitivity, pattern resolution, heat resistance and cross sectional profile of the patterned resist layer. The composition is characterized by the use of, as the film-forming resinous component, a hydroxyl-containing resinous ingredient which is a combination of a first resin of which from 30 to 60% of the hydroxyl groups are substituted by acid-dissociable solubility-reducing groups and a second resin of which from 5 to 20% of the hydroxyl groups are substituted by acid-dissociable groups of the same kind as in the first resin in a weight proportion of 1.9 to 9:1.
    Type: Grant
    Filed: April 3, 2002
    Date of Patent: January 13, 2004
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kazufumi Sato, Satoshi Maemori, Taku Nakao, Kazuyuki Nitta
  • Patent number: 6605417
    Abstract: Disclosed is a method for decreasing the surface defects of a patterned photoresist layer on a substrate surface obtained by the procedure comprising the steps of (a) forming a photoresist layer of a positive-working chemical-amplification photoresist composition on the substrate surface, (b) patternwise exposing the photoresist layer to actinic rays, (c) subjecting the patternwise-exposed photoresist layer to a post-exposure baking treatment and (d) a development treatment. The improvement can be accomplished by bringing the photoresist layer after the post-exposure baking treatment into contact with an aqueous acidic solution having a pH of 3.5 or lower for 1 to 90 seconds. The acid contained in the aqueous acidic solution is preferably an aromatic sulfonic acid or, more preferably, a diphenyl ether sulfonic acid such as dodecyl(diphenyl ether)disulfonic acids.
    Type: Grant
    Filed: January 30, 2001
    Date of Patent: August 12, 2003
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kazuyuki Nitta, Taku Nakao, Satoshi Maemori, Tatsuya Matsumi
  • Publication number: 20030138736
    Abstract: Disclosed is a method for decreasing the surface defects of a patterned photoresist layer on a substrate surface obtained by the procedure comprising the steps of (a) forming a photoresist layer of a positive-working chemical-amplification photoresist composition on the substrate surface, (b) patternwise exposing the photoresist layer to actinic rays, (c) subjecting the patternwise-exposed photoresist layer to a post-exposure baking treatment and (d) a development treatment. The improvement can be accomplished by bringing the photoresist layer after the post-exposure baking treatment into contact with an aqueous acidic solution having a pH of 3.5 or lower for 1 to 90 seconds. The acid contained in the aqueous acidic solution is preferably an aromatic sulfonic acid or, more preferably, a diphenyl ether sulfonic acid such as dodecyl(diphenyl ether) disulfonic acids.
    Type: Application
    Filed: January 31, 2003
    Publication date: July 24, 2003
    Inventors: Kazuyuki Nitta, Taku Nakao, Satoshi Maemori, Tatsuya Matsumi
  • Patent number: 6444394
    Abstract: Disclosed is a novel chemical-amplification positive-working photoresist composition capable of giving a patterned resist layer with excellent properties such as photosensitivity, pattern resolution, heat resistance and cross sectional profile of the patterned resist layer. The composition is characterized by the use of, as the film-forming resinous component, a hydroxyl-containing resinous ingredient which a combination of a first resin of which from 30 to 60% the hydroxyl groups are substituted by acid-dissociable solubility-reducing groups and a second resin of which from 5 to 20% of the hydroxyl groups are substituted by acid-dissociable groups of the same kind as in the first resin a weight proportion of 1.9 to 9:1.
    Type: Grant
    Filed: March 8, 2000
    Date of Patent: September 3, 2002
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kazufumi Sato, Satoshi Maemori, Taku Nakao, Kazuyuki Nitta
  • Publication number: 20020110750
    Abstract: Disclosed is a novel chemical-amplification positive-working photoresist composition capable of giving a patterned resist layer with excellent properties such as photosensitivity, pattern resolution, heat resistance and cross sectional profile of the patterned resist layer. The composition is characterized by the use of, as the film-forming resinous component, a hydroxyl-containing resinous ingredient which is a combination of a first resin of which from 30 to 60% of the hydroxyl groups are substituted by acid-dissociable solubility-reducing groups and a second resin of which from 5 to 20% of the hydroxyl groups are substituted by acid-dissociable groups of the same kind as in the first resin in a weight proportion of 1.9 to 9:1.
    Type: Application
    Filed: April 3, 2002
    Publication date: August 15, 2002
    Inventors: Kazufumi Sato, Satoshi Maemori, Taku Nakao, Kazuyuki Nitta
  • Publication number: 20010014431
    Abstract: Disclosed is a method for decreasing the surface defects of a patterned photoresist layer on a substrate surface obtained by the procedure comprising the steps of (a) forming a photoresist layer of a positive-working chemical-amplification photoresist composition on the substrate surface, (b) patternwise exposing the photoresist layer to actinic rays, (c) subjecting the patternwise-exposed photoresist layer to a post-exposure baking treatment and (d) a development treatment. The improvement can be accomplished by bringing the photoresist layer after the post-exposure baking treatment into contact with an aqueous acidic solution having a pH of 3.5 or lower for 1 to 90 seconds. The acid contained in the aqueous acidic solution is preferably an aromatic sulfonic acid or, more preferably, a diphenyl ether sulfonic acid such as dodecyl(diphenyl ether) disulfonic acids.
    Type: Application
    Filed: January 30, 2001
    Publication date: August 16, 2001
    Inventors: Kazuyuki Nitta, Taku Nakao, Satoshi Maemori, Tatsuya Matsumi
  • Patent number: 5702862
    Abstract: A positive photoresist coating solution comprising (a) an alkali-soluble resin, (b) a quinone diazide group-containing compound, and (c) an organic solvent in an amount sufficient for dissolving said (a) and (b) components, wherein said organic solvent contains (i) propylene glycol monopropyl ether and (ii) 2-heptanone. The solution of the present invention exhibits excellent coating ability, sensitivity, thermostability, focal depth range, shape-profiling ability, and the like.
    Type: Grant
    Filed: January 31, 1997
    Date of Patent: December 30, 1997
    Assignee: Tokyo Ohka Kogyo Co., LTD.
    Inventors: Hayato Ohno, Taku Nakao, Hisanobu Harada, Shinichi Hidesaka, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 5601961
    Abstract: Disclosed is an improved positive-working photoresist composition comprising an alkali-soluble resin as a film-forming agent and a quinone diazide group-containing compound as a photosensitive agent. The most characteristic feature of the inventive composition consists in the unique formulation of the alkali-soluble resin which is a combination of two or three kinds of novolac resins selected from novolac resins (a), (b1) or (b2) and (c1) or (c2), each of which is characterized by the unique formulation of the phenolic compounds as a mixture to be subjected to a condensation reaction with an aldehyde compound to form the novolac resin.
    Type: Grant
    Filed: March 29, 1995
    Date of Patent: February 11, 1997
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kazuhiko Nakayama, Taku Nakao, Kousuke Doi, Nobuo Tokutake, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 5599653
    Abstract: An improvement is proposed in a double-coated patterning plate, which consists of a substrate, an undercoat levelling layer and a photoresist layer thereon, as well as in the patterning method therewith. Different from conventional double-coated patterning plate in which the undercoat levelling layer is formed from poly(methyl methacrylate) resin, the layer in the invention is formed from a copolymeric resin of methyl methacrylate and glycidyl methacrylate in a specified copolymerization ratio and the resin is admixed with 2,2',4,4'-tetrahydroxybenzophenone. By virtue of the use of this unique resin composition for the undercoat levelling layer, the troubles due to intermixing between the undercoat levelling layer and the photoresist layer thereon can be avoided to impart the patterned resist layer with excellent properties.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: February 4, 1997
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Taku Nakao, Hiroyuki Yamazaki, Nobuo Tokutake, Masato Saito, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 5498514
    Abstract: An improvement is proposed in a double-coated patterning plate, which consists of a substrate, an undercoat levelling layer and a photoresist layer thereon, as well as in the patterning method therewith. Different from conventional double-coated patterning plate in which the undercoat levelling layer is formed from poly(methyl methacrylate) resin, the layer in the invention is formed from a copolymeric resin of methyl methacrylate and glycidyl methacrylate in a specified copolymerization ratio and the resin is admixed with 2,2',4,4'-tetrahydroxybenzophenone. By virtue of the use of this unique resin composition for the undercoat levelling layer, the troubles due to intermixing between the undercoat levelling layer and the photoresist layer thereon can be avoided to impart the patterned resist layer with excellent properties.
    Type: Grant
    Filed: August 9, 1994
    Date of Patent: March 12, 1996
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Taku Nakao, Hiroyuki Yamazaki, Nobuo Tokutake, Masato Saito, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 5478692
    Abstract: Proposed is a novel positive-working photoresist composition suitable for use in the fine patterning works in the manufacture of electronic devices and capable of exhibiting excellent performance with high resolution, high sensitivity, wide range of focusing depth, large exposure dose latitude and other characteristics. The photoresist composition is formulated, in addition to the basic ingredients of an alkali-soluble novolac resin as a film-forming agent and photosensitive ingredient such as an ester of naphthoquinone-1,2-diazide sulfonic acid and a polyhydroxy compound, with a limited amount of 4,4'-bis(dialkylamino) benzophenone, e.g., 4,4'-bis(diethylamino) benzophenone, preferably, in combination with a polyhydroxy compound such as 4,6-bis[1-methyl-1-(4-hydroxyphenyl)ethyl]-1,3-dihydroxy phenol.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: December 26, 1995
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kousuke Doi, Taku Nakao, Remi Numata, Nobuo Tokutake, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 5434031
    Abstract: Disclosed is a positive-working photoresist composition suitable for use in the photolithographic fine patterning work in the manufacture of electronic devices such as VLSIs. The composition comprises, in addition to an alkali-soluble novolac resin as a film-forming ingredient and an esterification product of naphthoquinone-1,2-diazide sulfonic acid as a photosensitive ingredient, a unique additive compound which is an alkyl or aralkyl ester of 2-hydroxy benzoic acid, such as benzyl salicylate, or a phenol compound substituted at least one alkyl group such as 2-tert-butyl-4-methyl phenol. By virtue of the addition of this unique additive, the inventive photoresist composition exhibits an excellent performance of suppressing the standing wave effect in addition to the excellent photosensitivity, resolving power and depth of focusing in the patterning exposure to light as well as good heat resistance of the patterned resist layer.
    Type: Grant
    Filed: November 17, 1993
    Date of Patent: July 18, 1995
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Taku Nakao, Remi Numata, Kousuke Doi, Nobuo Tokutake, Hidekatsu Kohara, Toshimasa Nakayama