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: 11604451
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. The area comprises a plurality of pixels, and the original set of exposure information comprises dosages for the plurality of pixels in the area. A backscatter is calculated for a sub area of the area based on the original set of exposure information. A dosage for at least one pixel in a plurality of pixels in the sub area is increased, in a location where the backscatter of the sub area is below a pre-determined threshold, thereby increasing the backscatter of the sub area. A modified set of exposure information is output, including the increased dosage of the at least one pixel in the sub area.
    Type: Grant
    Filed: March 24, 2021
    Date of Patent: March 14, 2023
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, Abhishek Shendre, William E. Guthrie, Ryan Pearman
  • Patent number: 11592802
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.
    Type: Grant
    Filed: December 28, 2020
    Date of Patent: February 28, 2023
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Publication number: 20230032510
    Abstract: Some embodiments provide a method for calculating parasitic parameters for a pattern to be manufactured on an integrated circuit (IC) substrate. The method receives a definition of a wire structure as input. The method rasterizes the wire structure (e.g., produces pixel-based definition of the wire structure) to produce several images. Before rasterizing the wire structure, the method in some embodiments decomposes the wire structure into several components (e.g., several wires, wire segments or wire structure portions), which it then individually rasterizes. The method then uses the images as inputs to a neural network, which then calculates parasitic parameters associated with the wire structure. In some embodiments, the parasitic parameters include unwanted parasitic capacitance effects exerted on the wire structure. Conjunctively, or alternatively, these parameters include unwanted parasitic resistance and/or inductance effects on the wire structure.
    Type: Application
    Filed: August 16, 2022
    Publication date: February 2, 2023
    Inventors: Akira Fujimura, Nagesh Shirali, Donald Oriordan
  • Publication number: 20230035090
    Abstract: Methods for reticle enhancement technology (RET) for use with variable shaped beam (VSB) lithography include inputting a desired pattern to be formed on a substrate; determining an initial mask pattern from the desired pattern for the substrate; optimizing the initial mask pattern for wafer quality using a VSB exposure system; and outputting the optimized mask pattern. Methods for fracturing a pattern to be exposed on a surface using VSB lithography include inputting an initial pattern; overlaying the initial pattern with a two-dimensional grid, wherein an initial set of VSB shots are formed by the union of the initial pattern with locations on the grid; merging two or more adjacent shots in the initial set of VSB shots to create a larger shot in a modified set of VSB shots; and outputting the modified set of VSB shots.
    Type: Application
    Filed: July 30, 2021
    Publication date: February 2, 2023
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, P. Jeffrey Ungar, Nagesh Shirali
  • Publication number: 20230034170
    Abstract: Methods for reticle enhancement technology (RET) for use with variable shaped beam (VSB) lithography include inputting a desired pattern to be formed on a substrate; determining an initial mask pattern from the desired pattern for the substrate; optimizing the initial mask pattern for wafer quality using a VSB exposure system; and outputting the optimized mask pattern. Methods for fracturing a pattern to be exposed on a surface using VSB lithography include inputting an initial pattern; overlaying the initial pattern with a two-dimensional grid, wherein an initial set of VSB shots are formed by the union of the initial pattern with locations on the grid; merging two or more adjacent shots in the initial set of VSB shots to create a larger shot in a modified set of VSB shots; and outputting the modified set of VSB shots.
    Type: Application
    Filed: July 30, 2021
    Publication date: February 2, 2023
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, P. Jeffrey Ungar, Nagesh Shirali
  • Publication number: 20230027655
    Abstract: Some embodiments provide a method for calculating parasitic parameters for a pattern to be manufactured on an integrated circuit (IC) substrate. The method receives a definition of a wire structure as input. The method rasterizes the wire structure (e.g., produces pixel-based definition of the wire structure) to produce several images. Before rasterizing the wire structure, the method in some embodiments decomposes the wire structure into several components (e.g., several wires, wire segments or wire structure portions), which it then individually rasterizes. The method then uses the images as inputs to a neural network, which then calculates parasitic parameters associated with the wire structure. In some embodiments, the parasitic parameters include unwanted parasitic capacitance effects exerted on the wire structure. Conjunctively, or alternatively, these parameters include unwanted parasitic resistance and/or inductance effects on the wire structure.
    Type: Application
    Filed: July 22, 2022
    Publication date: January 26, 2023
    Inventors: Akira Fujimura, Nagesh Shirali, Donald Oriordan
  • Publication number: 20230024684
    Abstract: Some embodiments provide a method for calculating parasitic parameters for a pattern to be manufactured on an integrated circuit (IC) substrate. The method receives a definition of a wire structure as input. The method rasterizes the wire structure (e.g., produces pixel-based definition of the wire structure) to produce several images. Before rasterizing the wire structure, the method in some embodiments decomposes the wire structure into several components (e.g., several wires, wire segments or wire structure portions), which it then individually rasterizes. The method then uses the images as inputs to a neural network, which then calculates parasitic parameters associated with the wire structure. In some embodiments, the parasitic parameters include unwanted parasitic capacitance effects exerted on the wire structure. Conjunctively, or alternatively, these parameters include unwanted parasitic resistance and/or inductance effects on the wire structure.
    Type: Application
    Filed: August 16, 2022
    Publication date: January 26, 2023
    Inventors: Akira Fujimura, Nagesh Shirali, Donald Oriordan
  • Publication number: 20220128899
    Abstract: Methods for calculating a pattern to be manufactured on a substrate include inputting a physical design pattern, determining a plurality of possible neighborhoods for the physical design pattern, generating a plurality of possible mask designs for the physical design pattern, calculating a plurality of possible patterns on the substrate, calculating a variation band from the plurality of possible patterns, and modifying the physical design pattern to reduce the variation band. Embodiments also include inputting a set of parameters for a neural network to calculate a pattern to be manufactured on a substrate, calculating a plurality of patterns to be manufactured on the substrate for the physical design in each possible neighborhood of the plurality of possible neighborhoods, training the neural network with the calculated plurality of patterns, and adjusting the set of parameters to reduce the manufacturing variation for the calculated plurality of patterns to be manufactured on a substrate.
    Type: Application
    Filed: October 22, 2020
    Publication date: April 28, 2022
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Nagesh Shirali, Donald Oriordan
  • Patent number: 11264206
    Abstract: Methods for fracturing or mask data preparation are disclosed in which a set of single-beam charged particle beam shots is input; a calculated image is calculated using a neural network, from the set of single-beam charged particle beam shots; and a set of multi-beam shots is generated based on the calculated image, to convert the set of single-beam charged particle beam shots to the set of multi-beam shots which will produce a surface image on the surface. Methods for training a neural network include inputting a set of single-beam charged particle beam shots; calculating a set of calculated images using the set of single-beam charged particle beam shots; and training the neural network with the set of calculated images.
    Type: Grant
    Filed: October 17, 2019
    Date of Patent: March 1, 2022
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Thang Nguyen, Ajay Baranwal, Michael J. Meyer, Suhas Pillai
  • Publication number: 20210313143
    Abstract: Methods for exposing a desired shape in an area on a surface using a charged particle beam system include determining a local pattern density for the area of the desired shape based on an original set of exposure information. A backscatter for a sub area is calculated, based on the original set of exposure information. Dosage for at least one pixel in a plurality of pixels in the sub area is increased, in a location where the backscatter of the sub area is below a pre-determined threshold, thereby increasing the backscatter of the sub area. A pre-PEC maximum dose is determined for the local pattern density, based on a pre-determined target post-PEC maximum dose. The original set of exposure information is modified with the pre-PEC maximum dose and the increased dosage of the at least one pixel in the sub area to create a modified set of exposure information.
    Type: Application
    Filed: June 17, 2021
    Publication date: October 7, 2021
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, Abhishek Shendre, William E. Guthrie, Ryan Pearman
  • Patent number: 11062878
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes determining a local pattern density for the area of the pattern based on an original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PLC maximum dose.
    Type: Grant
    Filed: July 21, 2020
    Date of Patent: July 13, 2021
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Publication number: 20210208569
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. The area comprises a plurality of pixels, and the original set of exposure information comprises dosages for the plurality of pixels in the area. A backscatter is calculated for a sub area of the area based on the original set of exposure information. A dosage for at least one pixel in a plurality of pixels in the sub area is increased, in a location where the backscatter of the sub area is below a pre-determined threshold, thereby increasing the backscatter of the sub area. A modified set of exposure information is output, including the increased dosage of the at least one pixel in the sub area.
    Type: Application
    Filed: March 24, 2021
    Publication date: July 8, 2021
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, Abhishek Shendre, William E. Guthrie, Ryan Pearman
  • Publication number: 20210116884
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.
    Type: Application
    Filed: December 28, 2020
    Publication date: April 22, 2021
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Patent number: 10884395
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.
    Type: Grant
    Filed: December 22, 2018
    Date of Patent: January 5, 2021
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Publication number: 20200373122
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes determining a local pattern density for the area of the pattern based on an original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PLC maximum dose.
    Type: Application
    Filed: July 21, 2020
    Publication date: November 26, 2020
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Patent number: 10748744
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam system is disclosed and includes inputting an original set of exposure information for the area and inputting a target post-proximity effect correction (PEC) maximum dose. A local pattern density is calculated for the area of the pattern based on the original set of exposure information. A pre-PEC maximum dose is determined for the area. The original set of exposure information is modified with the pre-PEC maximum dose.
    Type: Grant
    Filed: May 24, 2019
    Date of Patent: August 18, 2020
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Publication number: 20200201286
    Abstract: A method for exposing a pattern in an area on a surface using a charged particle beam lithography is disclosed and includes inputting an original set of exposure information for the area. A backscatter is calculated for the area of the pattern based on the exposure information. An artificial background dose is determined for the area. The artificial background dose comprises additional exposure information and is combined with the original set of exposure information creating a modified set of exposure information. A system for exposing a pattern in an area on a surface using a charged particle beam lithography is also disclosed.
    Type: Application
    Filed: December 22, 2018
    Publication date: June 25, 2020
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Nagesh Shirali, William E. Guthrie, Ryan Pearman
  • Publication number: 20200051781
    Abstract: Methods for fracturing or mask data preparation are disclosed in which a set of single-beam charged particle beam shots is input; a calculated image is calculated using a neural network, from the set of single-beam charged particle beam shots; and a set of multi-beam shots is generated based on the calculated image, to convert the set of single-beam charged particle beam shots to the set of multi-beam shots which will produce a surface image on the surface. Methods for training a neural network include inputting a set of single-beam charged particle beam shots; calculating a set of calculated images using the set of single-beam charged particle beam shots; and training the neural network with the set of calculated images.
    Type: Application
    Filed: October 17, 2019
    Publication date: February 13, 2020
    Applicant: D2S, Inc.
    Inventors: Akira Fujimura, Thang Nguyen, Ajay Baranwal, Michael J. Meyer, Suhas Pillai
  • Patent number: 10460071
    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: Grant
    Filed: October 20, 2016
    Date of Patent: October 29, 2019
    Assignee: D2S, Inc.
    Inventors: Akira Fujimura, Harold Robert Zable, Ryan Pearman, William Guthrie
  • 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