Patents by Inventor Hidekatsu Kohara

Hidekatsu Kohara 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: 6939926
    Abstract: A phenol novolak resin has a peak intensity ratio of ortho-ortho bond (o-o)/ortho-para bond (o-p)/para-para bond (p-p) in a resin structure not substantially varying in each molecular weight fraction and has a weight average molecular weight (Mw) of 3000 to 20000 in terms of polystyrene, which peak intensity ratio is detected by 13C-NMR analysis. The phenol novolak resin can form both dense pattern and isolation pattern with good shapes in the formation of a fine resist pattern of not more than 0.35 ?m and has satisfactory sensitivity, definition, and focal depth range properties, and has a resin composition being uniform in each molecular weight fraction. A process for producing the phenol novolak resin, and a positive photoresist composition using the resin are also provided.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: September 6, 2005
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Ken Miyagi, Yasuhide Ohuchi, Atsuko Hirata, Kousuke Doi, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6884566
    Abstract: A novel copolymer includes a repeating unit (B) derived from an unsaturated carboxylic anhydride, a repeating unit (C) represented by Formula (II), and a repeating unit (D) represented by Formula (III).
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: April 26, 2005
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Tsuyoshi Nakamura, Taeko Ikegawa, Atsushi Sawano, Kousuke Doi, Hidekatsu Kohara
  • Publication number: 20040167312
    Abstract: A phenol novolak resin has a peak intensity ratio of ortho-ortho bond (o-o)/ortho-para bond (o-p)/para-para bond (p-p) in a resin structure not substantially varying in each molecular weight fraction and has a weight average molecular weight (Mw) of 3000 to 20000 in terms of polystyrene, which peak intensity ratio is detected by 13C-NMR analysis. The phenol novolak resin can form both dense pattern and isolation pattern with good shapes in the formation of a fine resist pattern of not more than 0.35 &mgr;m and has satisfactory sensitivity, definition, and focal depth range properties, and has a resin composition being uniform in each molecular weight fraction. A process for producing the phenol novolak resin, and a positive photoresist composition using the resin are also provided.
    Type: Application
    Filed: February 9, 2004
    Publication date: August 26, 2004
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Ken Miyagi, Yasuhide Ohuchi, Atsuko Hirata, Kousuke Doi, Hidekatsu Kohara, Toshimasa Nakayama
  • Publication number: 20040096772
    Abstract: A novel copolymer includes a repeating unit (B) derived from an unsaturated carboxylic anhydride, a repeating unit (C) represented by Formula (II), and a repeating unit (D) represented by Formula (III).
    Type: Application
    Filed: October 16, 2003
    Publication date: May 20, 2004
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Tsuyoshi Nakamura, Taeko Ikegawa, Atsushi Sawano, Kousuke Doi, Hidekatsu Kohara
  • Publication number: 20030186171
    Abstract: A novel copolymer includes a repeating unit (B) derived from an unsaturated carboxylic anhydride, a repeating unit (C) represented by Formula (II), and a repeating unit (D) represented by Formula (III).
    Type: Application
    Filed: March 4, 2003
    Publication date: October 2, 2003
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Tsuyoshi Nakamura, Taeko Ikegawa, Atsushi Sawano, Kousuke Doi, Hidekatsu Kohara
  • Patent number: 6620978
    Abstract: The present invention provides a positive photoresist composition including (A) an alkali-soluble resin and (B) a photosensitizer, and the ingredient (B) is a quinonediazide ester of, for example, 2,6-bis[4-hydroxy-3-(2-hydroxy-3,5-dimethylbenzyl)-2,5-dimethylbenzyl]-4-methylphenol, where the average degree of esterification of 20% to 80%.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: September 16, 2003
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Satoshi Shimatani, Ken Miyagi, Satoshi Niikura, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6566031
    Abstract: A positive photoresist composition includes (A) an alkali-soluble resin, (B) a photosensitizer including, for example, a quinonediazide ester of bis[2,5-dimethyl-3-(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane, and (C) a compound having a gram absorption coefficient of 5 to 60 with respect to light with a wavelength of 365 nm.
    Type: Grant
    Filed: September 26, 2000
    Date of Patent: May 20, 2003
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Takako Suzuki, Kousuke Doi, Hidekatsu Kohara, Toshimasa Nakayama
  • Publication number: 20030054283
    Abstract: The present invention provides a positive photoresist composition including (A) an alkali-soluble resin and (B) a photosensitizer, and the ingredient (B) is a quinonediazide ester of, for example, 2,6-bis[4-hydroxy-3-(2-hydroxy-3,5-dimethylbenzyl)-2,5-dimethylbenzyl]-4-methylphenol, where the average degree of esterification of 20% to 80%.
    Type: Application
    Filed: July 31, 2002
    Publication date: March 20, 2003
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Satoshi Shimatani, Ken Miyagi, Satoshi Niikura, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6517993
    Abstract: A novel copolymer includes a repeating unit (A) represented by, for example, Formula (I) below, and a repeating unit (B) derived from an unsaturated carboxylic anhydride. The novel copolymer is suitable for the preparation of a photoresist composition that has satisfactory transparency, high sensitivity and definition and exhibits satisfactory DOF properties in the field of photolithography using a deep UV light source. By the use of the photoresist composition, a process forms a resist pattern with a high aspect ratio.
    Type: Grant
    Filed: July 11, 2001
    Date of Patent: February 11, 2003
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Tsuyoshi Nakamura, Taeko Ikegawa, Atsushi Sawano, Kousuke Doi, Hidekatsu Kohara
  • Patent number: 6492085
    Abstract: The present invention provides a positive photoresist composition including (A) an alkali-soluble resin and (B) a photosensitizer, and the ingredient (B) is a quinonediazide ester of, for example, 2,6-bis[4-hydroxy-3-(2-hydroxy-3,5-dimethylbenzyl)-2,5-dimethylbenzyl]-4-methylphenol, where the average degree of esterification of 20% to 80%.
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: December 10, 2002
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Satoshi Shimatani, Ken Miyagi, Satoshi Niikura, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6475694
    Abstract: A positive photoresist composition includes (A) an alkali-soluble resin, in which part of phenolic hydroxyl groups is protected by an acid-decomposable group; (B) a quinonediazide ester; and (C) a compound which generates an acid upon irradiation of light with a wavelength of 365 nm. This positive photoresist composition can form a fine pattern of about 0.35 &mgr;m in the photolithographic process using i-ray (365 nm), is excellent in focal depth range properties in such an ultrafine region, and has a high sensitivity.
    Type: Grant
    Filed: May 24, 2001
    Date of Patent: November 5, 2002
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Kousuke Doi, Ken Miyagi, Atsuko Hirata, Hidekatsu Kohara, Toshimasa Nakayama
  • Publication number: 20020119390
    Abstract: Disclosed are a positive photoresist composition including (A) an alkali-soluble resin, (B) a photosensitizer containing a quinonediazide ester of, e.g., bis[2,5-dimethyl-3-(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane and (C) e.g., 2,6-bis(2,5-dimethyl-4-hydroxybenzyl)-4-methylphenol; and a process including the steps of coating the composition onto a 8 to 12-inch substrate, drying, exposing and developing the same. The composition which can form a pattern having a good shape whose dimensional changes are minimized in a wide range over surface of the substrate, particularly in processes using a large-diameter substrate, and the process for forming a resist pattern using the composition are provided.
    Type: Application
    Filed: February 28, 2002
    Publication date: August 29, 2002
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Takako Suzuki, Sachiko Tamura, Kousuke Doi, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6417317
    Abstract: A novolak resin precursor is composed of bonded phenolic moieties, one of the hydrogen atoms in the o- or p-positions relative to the hydroxy group of each phenolic moiety is substituted with an alkyl or alkenyl group having 1 to 3 carbon atoms, and the other two hydrogen atoms are bonded through methylene bonds. The content of ortho-ortho bonding is 30 to 70% relative to the number of total methylene bonds and the weight average molecular weight of the precursor is 300 to 10,000. A novolak resin is obtained from this precursor, and a positive photoresist composition comprises this novolak resin. The invention provides a positive photoresist composition that comprises less binuclear compounds, suppresses scum formation, is excellent in terms of definition and coating performance and provides a resist pattern having satisfactory heat resistance.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: July 9, 2002
    Assignee: Togyo Ohka Kogyo Co., Ltd.
    Inventors: Ken Miyagi, Kousuke Doi, Ryuusaku Takahashi, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6406827
    Abstract: A positive photoresist composition includes (A) an alkali-soluble resin, (B) a quinonediazide ester of, e.g., bis[2,5-dimethyl-3-(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane and/or 2,4-bis[4-hydroxy-3-(4-hydroxybenzyl)-5-methylbenzyl]-6-cyclohexylphenol, and (C) 4,4′-bis(diethylamino)benzophenone. The composition exhibits high sensitivity and definition and improved focal depth range properties and underexposure margin.
    Type: Grant
    Filed: May 28, 1999
    Date of Patent: June 18, 2002
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Takako Suzuki, Kousuke Doi, Hidekatsu Kohara, Toshimasa Nakayama
  • Patent number: 6379859
    Abstract: Disclosed are a positive photoresist composition including (A) an alkali-soluble resin, (B) a photosensitizer containing a quinonediazide ester of, e.g., bis[2,5-dimethyl-3-(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane and (C) e.g., 2,6-bis(2,5-dimethyl-4-hydroxybenzyl)-4-methylphenol; and a process including the steps of coating the composition onto a 8 to 12-inch substrate, drying, exposing and developing the same. The composition which can form a pattern having a good shape whose dimensional changes are minimized in a wide range over surface of the substrate, particularly in processes using a large-diameter substrate, and the process for forming a resist pattern using the composition are provided.
    Type: Grant
    Filed: June 1, 1999
    Date of Patent: April 30, 2002
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Takako Suzuki, Sachiko Tamura, Kousuke Doi, Hidekatsu Kohara, Toshimasa Nakayama
  • Publication number: 20020031719
    Abstract: A novel copolymer includes a repeating unit (A) represented by, for example, Formula (I) below, and a repeating unit (B) derived from an unsaturated carboxylic anhydride. The novel copolymer is suitable for the preparation of a photoresist composition that has satisfactory transparency, high sensitivity and definition and exhibits satisfactory DOF properties in the field of photolithography using a deep UV light source. By the use of the photoresist composition, a process forms a resist pattern with a high aspect ratio.
    Type: Application
    Filed: July 11, 2001
    Publication date: March 14, 2002
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Tsuyoshi Nakamura, Taeko Ikegawa, Atsushi Sawano, Kousuke Doi, Hidekatsu Kohara
  • Publication number: 20020031720
    Abstract: A novel copolymer includes a repeating unit (B) derived from an unsaturated carboxylic anhydride, a repeating unit (C) represented by Formula (II), and a repeating unit (D) represented by Formula (III).
    Type: Application
    Filed: July 11, 2001
    Publication date: March 14, 2002
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Tsuyoshi Nakamura, Taeko Ikegawa, Atsushi Sawano, Kousuke Doi, Hidekatsu Kohara
  • Publication number: 20020012865
    Abstract: Disclosed are a positive photoresist composition including (A) an alkali-soluble resin, (B) a photosensitizer containing a quinonediazide ester of, e.g., bis[2,5-dimethyl-3-(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane and (C) e.g., 2,6-bis(2,5-dimethyl-4-hydroxybenzyl)-4-methylphenol; and a process including the steps of coating the composition onto a 8 to 12-inch substrate, drying, exposing and developing the same. The composition which can form a pattern having a good shape whose dimensional changes are minimized in a wide range over surface of the substrate, particularly in processes using a large-diameter substrate, and the process for forming a resist pattern using the composition are provided.
    Type: Application
    Filed: June 1, 1999
    Publication date: January 31, 2002
    Inventors: TAKAKO SUZUKI, SACHIKO TAMURA, KOUSUKE DOI, HIDEKATSU KOHARA, TOSHIMASA NAKAYAMA
  • Publication number: 20020001769
    Abstract: A positive photoresist composition includes (A) an alkali-soluble resin, in which part of phenolic hydroxyl groups is protected by an acid-decomposable group; (B) a quinonediazide ester; and (C) a compound which generates an acid upon irradiation of light with a wavelength of 365 nm. This positive photoresist composition can form a fine pattern of about 0.35 &mgr;m in the photolithographic process using i-ray (365 nm), is excellent in focal depth range properties in such an ultrafine region, and has a high sensitivity.
    Type: Application
    Filed: May 24, 2001
    Publication date: January 3, 2002
    Applicant: TOKYO OHKA KOGYO CO., LTD.
    Inventors: Kousuke Doi, Ken Miyagi, Atsuko Hirata, Hidekatsu Kohara, Toshimasa Nakayama
  • Publication number: 20010053493
    Abstract: A positive photoresist composition includes (A) an alkali-soluble resin, (B) a quinonediazide ester of, e.g., bis[2,5-dimethyl-3-(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane and/or 2,4-bis[4-hydroxy-3-(4-hydroxybenzyl)-5-methylbenzyl]-6-cyclohexylphenol, and (C) 4,4′-bis(diethylamino)benzophenone. The composition exhibits high sensitivity and definition and improved focal depth range properties and underexposure margin.
    Type: Application
    Filed: May 28, 1999
    Publication date: December 20, 2001
    Inventors: TAKAKO SUZUKI, KOUSUKE DOI, HIDEKATSU KOHARA, TOSHIMASA NAKAYAMA