Patents by Inventor Akira Fujimura

Akira Fujimura 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: 10431422
    Abstract: A method for mask process correction or forming a pattern on a reticle using charged particle beam lithography is disclosed, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern, and where pattern exposure information is modified to increase edge slope of the reticle pattern where sensitivity of the wafer pattern is high. A method for fracturing or mask data preparation is also disclosed, where pattern exposure information is determined that can form a pattern on a reticle using charged particle beam lithography, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, and where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern.
    Type: Grant
    Filed: December 13, 2017
    Date of Patent: October 1, 2019
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Kazuyuki Hagiwara, Robert C. Pack
  • Publication number: 20190237299
    Abstract: A method for fracturing or mask data preparation is disclosed in which a plurality of single-beam charged particle beam shots is used to create a plurality of multi-beam shots, where multi-beam exposure information is determined for each of the single-beam shots, and then the resulting multi-beam exposure information is used to generate a set of multi-beam shots. Additionally, a method for fracturing or mask data preparation is disclosed in which a plurality of single-beam shots is used to generate a set of multi-beam shots by calculating an image which the single-beam shots would form on a surface.
    Type: Application
    Filed: April 10, 2019
    Publication date: August 1, 2019
    Applicant: D2S, Inc.
    Inventor: Akira Fujimura
  • Patent number: 10317790
    Abstract: A method for optical proximity correction includes inputting a physical design having a plurality of shapes. Each shape has a plurality of corners, and the physical design is to be exposed on a surface of a substrate. A set of sub-resolution assist features (SRAFs) for the physical design is determined, where a plurality of SRAFs in the set of SRAFs interact. The plurality of SRAFs together provide better dimensional control of one corner of one shape in the plurality of shapes, when exposed on the substrate, compared to using a single SRAF to control a dimension of the one corner. The plurality of SRAFs includes a positive SRAF and a negative SRAF. A modified physical design is output, where the modified physical design comprises the physical design, as modified by the set of SRAFs.
    Type: Grant
    Filed: September 11, 2017
    Date of Patent: June 11, 2019
    Assignee: D2S, Inc.
    Inventors: Leo Pang, Akira Fujimura
  • Patent number: 10290467
    Abstract: A method for fracturing or mask data preparation is disclosed in which a plurality of single-beam charged particle beam shots is used to create a plurality of multi-beam shots, where multi-beam exposure information is determined for each of the single-beam shots, and then the resulting multi-beam exposure information is used to generate a set of multi-beam shots. Additionally, a method for fracturing or mask data preparation is disclosed in which a plurality of single-beam shots is used to generate a set of multi-beam shots by calculating an image which the single-beam shots would form on a surface.
    Type: Grant
    Filed: March 10, 2015
    Date of Patent: May 14, 2019
    Assignee: D2S, Inc.
    Inventor: Akira Fujimura
  • Publication number: 20180374675
    Abstract: A method and system for fracturing or mask data preparation or optical proximity correction or proximity effect correction or mask process correction is disclosed in which a set of shaped beam shots is determined that is capable of forming a pattern on a surface, where the set of shots provides different dosages to different parts of the pattern, and where the dose margin from the set of shots is calculated. A method for forming patterns on a surface is also disclosed.
    Type: Application
    Filed: August 30, 2018
    Publication date: December 27, 2018
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable
  • Patent number: 10101648
    Abstract: A method and system for fracturing or mask data preparation is disclosed in which a desired substrate pattern for a substrate is input. A plurality of charged particle beam shots is then determined which will form a reticle pattern on a reticle, where the reticle pattern will produce a substrate pattern on the substrate using an optical lithography process, wherein the substrate pattern is within a predetermined tolerance of the desired substrate pattern. A similar method and a similar system for forming a pattern on a reticle are also disclosed.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: October 16, 2018
    Assignee: D2S, Inc.
    Inventor: Akira Fujimura
  • Patent number: 10031413
    Abstract: A method for mask data preparation (MDP) is disclosed, in which a set of shots is determined that will form a pattern on a reticle, where the determination includes calculating the pattern that will be formed on a substrate using an optical lithographic process with a reticle formed using the set of shots. A method for optical proximity correction (OPC) or MDP is also disclosed, in which a preliminary set of charged particle beam shots is generated using a preliminary mask model, and then the shots are modified by calculating both a reticle pattern using a final mask model, and a resulting substrate pattern. A method for OPC is also disclosed, in which an ideal pattern for a photomask is calculated from a desired substrate pattern, where the model used in the calculation includes only optical lithography effects and/or substrate processing effects.
    Type: Grant
    Filed: July 25, 2016
    Date of Patent: July 24, 2018
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Anatoly Aadamov, Eldar Khaliullin, Ingo Bork
  • Publication number: 20180108513
    Abstract: A method for mask process correction or forming a pattern on a reticle using charged particle beam lithography is disclosed, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern, and where pattern exposure information is modified to increase edge slope of the reticle pattern where sensitivity of the wafer pattern is high. A method for fracturing or mask data preparation is also disclosed, where pattern exposure information is determined that can form a pattern on a reticle using charged particle beam lithography, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, and where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern.
    Type: Application
    Filed: December 13, 2017
    Publication date: April 19, 2018
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Kazuyuki Hagiwara, Robert C. Pack
  • Publication number: 20180074393
    Abstract: A method for optical proximity correction includes inputting a physical design having a plurality of shapes. Each shape has a plurality of corners, and the physical design is to be exposed on a surface of a substrate. A set of sub-resolution assist features (SRAFs) for the physical design is determined, where a plurality of SRAFs in the set of SRAFs interact. The plurality of SRAFs together provide better dimensional control of one corner of one shape in the plurality of shapes, when exposed on the substrate, compared to using a single SRAF to control a dimension of the one corner. The plurality of SRAFs includes a positive SRAF and a negative SRAF. A modified physical design is output, where the modified physical design comprises the physical design, as modified by the set of SRAFs.
    Type: Application
    Filed: September 11, 2017
    Publication date: March 15, 2018
    Applicant: D2S, Inc.
    Inventors: Leo Pang, Akira Fujimura
  • Patent number: 9859100
    Abstract: A method for mask process correction or forming a pattern on a reticle using charged particle beam lithography is disclosed, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern, and where pattern exposure information is modified to increase edge slope of the reticle pattern where sensitivity of the wafer pattern is high. A method for fracturing or mask data preparation is also disclosed, where pattern exposure information is determined that can form a pattern on a reticle using charged particle beam lithography, where the reticle is to be used in an optical lithographic process to form a pattern on a wafer, and where sensitivity of the wafer pattern is calculated with respect to changes in dimension of the reticle pattern.
    Type: Grant
    Filed: May 17, 2016
    Date of Patent: January 2, 2018
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Kazuyuki Hagiwara, Robert C. Pack
  • Publication number: 20170322485
    Abstract: A method and system for fracturing or mask data preparation is disclosed in which a desired substrate pattern for a substrate is input. A plurality of charged particle beam shots is then determined which will form a reticle pattern on a reticle, where the reticle pattern will produce a substrate pattern on the substrate using an optical lithography process, wherein the substrate pattern is within a predetermined tolerance of the desired substrate pattern. A similar method and a similar system for forming a pattern on a reticle are also disclosed.
    Type: Application
    Filed: July 20, 2017
    Publication date: November 9, 2017
    Applicant: D2S, Inc.
    Inventor: Akira Fujimura
  • Patent number: 9797453
    Abstract: A wheel bearing apparatus has an outer member, an inner member, at least one inner ring fit onto the inner member. Double row rolling elements are rollably arranged between the outer and inner raceway surfaces, via cages. A seal is mounted on one end of the outer member. The seal has side lips adapted to be in sliding contact with the wheel hub. The seal has three inclined side lips each extending radially outward from the seal body. The lips are adapted to be in sliding contact with the base of the wheel mounting flange. Interference of the side lips against the base of the wheel mounting flange is set so that the radially inner side lip has a smaller interference than that of the radially outer side lips, in order.
    Type: Grant
    Filed: October 3, 2006
    Date of Patent: October 24, 2017
    Assignee: NTN Corporation
    Inventors: Takayuki Norimatsu, Hiroaki Itakura, Hironori Imanaka, Syougo Suzuki, Isao Hirai, Hiroya Kato, Akira Fujimura, Kikuo Fukada
  • Publication number: 20170213698
    Abstract: A method and system for fracturing or mask data preparation or optical proximity correction or proximity effect correction or mask process correction is disclosed in which a set of shaped beam shots is determined that is capable of forming a pattern on a surface, where the set of shots provides different dosages to different parts of the pattern, and where the dose margin from the set of shots is calculated. A method for forming patterns on a surface is also disclosed.
    Type: Application
    Filed: April 7, 2017
    Publication date: July 27, 2017
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable
  • Patent number: 9715169
    Abstract: A method and system for fracturing or mask data preparation is disclosed in which a desired substrate pattern for a substrate is input. A plurality of charged particle beam shots is then determined which will form a reticle pattern on a reticle, where the reticle pattern will produce a substrate pattern on the substrate using an optical lithography process, wherein the substrate pattern is within a predetermined tolerance of the desired substrate pattern. A similar method and a similar system for forming a pattern on a reticle are also disclosed.
    Type: Grant
    Filed: May 17, 2016
    Date of Patent: July 25, 2017
    Assignee: D2S, Inc.
    Inventor: Akira Fujimura
  • Publication number: 20170124247
    Abstract: In some embodiments, data is received defining a plurality of shot groups that will be delivered by a charged particle beam writer during an overall time period, where a first shot group will be delivered onto a first designated area at a first time period. A temperature of the first designated area at a different time period is determined. In some embodiments, the different time period is when secondary effects of exposure from a second shot group are received at the first designated area. In some embodiments, transient temperatures of a target designated area are determined at time periods when exposure from a shot group is received. An effective temperature of the target area is determined, using the transient temperatures and applying a compensation factor based on an amount of exposure received during that time period. A shot in the target shot group is modified based on the effective temperature.
    Type: Application
    Filed: October 20, 2016
    Publication date: May 4, 2017
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Ryan Pearman, William Guthrie
  • Patent number: 9625809
    Abstract: A method and system for fracturing or mask data preparation or optical proximity correction or proximity effect correction or mask process correction is disclosed in which a set of shaped beam shots is determined that is capable of forming a pattern on a surface, where the set of shots provides different dosages to different parts of the pattern, and where the dose margin from the set of shots is calculated. A method for forming patterns on a surface is also disclosed.
    Type: Grant
    Filed: June 16, 2016
    Date of Patent: April 18, 2017
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable
  • Patent number: 9612530
    Abstract: A method and system for fracturing or mask data preparation are presented in which a set of shots is determined for a multi-beam charged particle beam writer. The edge slope of a pattern formed by the set of shots is calculated. An edge of the pattern which has an edge slope below a target level is identified, and the dosage of a beamlet in a shot in the set of shots is increased to improve the edge slope. The improved edge slope remains less than the target level.
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: April 4, 2017
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Kazuyuki Hagiwara, Stephen F. Meier, Ingo Bork
  • Publication number: 20170023862
    Abstract: In a method for fracturing or mask data preparation or mask process correction for charged particle beam lithography, a plurality of shots are determined that will form a pattern on a surface, where shots are determined so as to reduce sensitivity of the resulting pattern to changes in beam blur (?f). In some embodiments, the sensitivity to changes in ?f is reduced by varying the charged particle surface dosage for a portion of the pattern. Methods for forming patterns on a surface, and for manufacturing an integrated circuit are also disclosed, in which pattern sensitivity to changes in ?f is reduced.
    Type: Application
    Filed: October 8, 2016
    Publication date: January 26, 2017
    Inventors: Akira Fujimura, Ingo Bork
  • Patent number: 9534635
    Abstract: A wheel bearing apparatus has an outer member, an inner member, at least one inner ring fit onto the inner member. Double row rolling elements are rollably arranged between the outer and inner raceway surfaces, via cages. A seal is mounted on one end of the outer member. The seal has side lips adapted to be in sliding contact with the wheel hub. The seal has three inclined side lips each extending radially outward from the seal body. The lips are adapted to be in sliding contact with the base of the wheel mounting flange. Interference of the side lips against the base of the wheel mounting flange is set so that the radially inner side lip has a smaller interference than that of the radially outer side lips, in order.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: January 3, 2017
    Assignee: NTN Corporation
    Inventors: Takayuki Norimatsu, Hiroaki Itakura, Hironori Imanaka, Syougo Suzuki, Isao Hirai, Hiroya Kato, Akira Fujimura, Kikuo Fukada
  • Publication number: 20160334700
    Abstract: A method for mask data preparation (MDP) is disclosed, in which a set of shots is determined that will form a pattern on a reticle, where the determination includes calculating the pattern that will be formed on a substrate using an optical lithographic process with a reticle formed using the set of shots. A method for optical proximity correction (OPC) or MDP is also disclosed, in which a preliminary set of charged particle beam shots is generated using a preliminary mask model, and then the shots are modified by calculating both a reticle pattern using a final mask model, and a resulting substrate pattern. A method for OPC is also disclosed, in which an ideal pattern for a photomask is calculated from a desired substrate pattern, where the model used in the calculation includes only optical lithography effects and/or substrate processing effects.
    Type: Application
    Filed: July 25, 2016
    Publication date: November 17, 2016
    Inventors: Akira Fujimura, Anatoly Aadamov, Eldar Khaliullin, Ingo Bork