Patents by Inventor Xuelong Shi

Xuelong Shi 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).

  • Publication number: 20060080633
    Abstract: A method of generating a mask for use in an imaging process pattern. The method includes the steps of: (a) obtaining a desired target pattern having a plurality of features to be imaged on a substrate; (b) simulating a wafer image utilizing the target pattern and process parameters associated with a defined process; (c) defining at least one feature category; (d) identifying features in the target pattern that correspond to the at least one feature category, and recording an error value for each feature identified as corresponding to the at least one feature category; and (e) generating a statistical summary which indicates the error value for each feature identified as corresponding to the at least one feature category.
    Type: Application
    Filed: September 14, 2005
    Publication date: April 13, 2006
    Inventors: Michael Hsu, Thomas Laidig, Kurt Wampler, Duan-Fu Hsu, Xuelong Shi
  • Publication number: 20050210437
    Abstract: A method for modeling a photolithography process which includes the steps of generating a calibrated model of the photolithography process capable of estimating an image to be produced by the photolithography process when utilized to image a mask pattern containing a plurality features; and determining an operational window of the calibrated model, which defines whether or not the calibrated model can accurately estimate the image to be produced by a given feature in the mask pattern.
    Type: Application
    Filed: January 27, 2005
    Publication date: September 22, 2005
    Inventors: Xuelong Shi, Jang Chen
  • Publication number: 20050196682
    Abstract: A method of generating a mask for use in a photolithography process. The method includes the steps of determining a target mask pattern having a plurality of features to be imaged and an illumination system to be utilized to image the mask; identifying a critical pitch within the target pattern and optimizing illumination settings of the illumination system for imaging the critical pitch; identifying a forbidden pitch within the target pattern; and modifying the transmittance of the features having a pitch equal to or substantially equal to the forbidden pitch such that the exposure latitude of the features equal to or substantially equal to the forbidden pitch is increased.
    Type: Application
    Filed: November 5, 2004
    Publication date: September 8, 2005
    Inventors: Stephen Hsu, Jang Chen, Xuelong Shi, Douglas Van Den Broeke
  • Publication number: 20050179886
    Abstract: A method for generating models for simulating the imaging performance of a plurality of exposure tools. The method includes the steps of: generating a calibrated model for a first exposure tool capable of estimating an image to be produced by the first exposure tool for a given photolithography process, where the calibrated model includes a first set of basis functions; generating a model of a second exposure tool capable of estimating an image to be produced by the second exposure tool for the photolithography process, where the model includes a second set of basis functions; and representing the second set of basis functions as a linear combination of the first set of basis functions so as to generate an equivalent model function corresponding to the second exposure tool, where the equivalent model function produces a simulated image corresponding to the image generated by the second exposure tool for the photolithography process.
    Type: Application
    Filed: January 28, 2005
    Publication date: August 18, 2005
    Inventors: Xuelong Shi, Jang Chen
  • Publication number: 20050149902
    Abstract: Model OPC is developed based on eigen decomposition of an aerial image expected to be produced by a mask pattern on a surface of a resist. With the eigen decomposition method the aerial image intensity distribution around a point (x, y) is accurately described in the model. A scalar approach may be used in the eigen decomposition model which treats the light wave through the mask as a scalar quantity. A eigen decomposition alternatively may use a vector approach which utilizes a vector to describe the light wave and the pupil function. A predicted SPIF may be generated from the aerial image which may be used to verify the mask modeling process by comparing the predicted SPIF to an experimentally determined SPIF. The model OPC, once calibrated, may be used to evaluate performance of a mask and refine features of the mask.
    Type: Application
    Filed: November 5, 2004
    Publication date: July 7, 2005
    Inventors: Xuelong Shi, Robert Socha, Thomas Laidig, Douglas Broeke
  • Publication number: 20050142449
    Abstract: A method of generating a mask design having optical proximity correction features disposed therein.
    Type: Application
    Filed: September 3, 2004
    Publication date: June 30, 2005
    Inventors: Xuelong Shi, Jang Chen, Thomas Laidig, Kurt Wampler, Douglas Broeke
  • Publication number: 20050142470
    Abstract: Disclosed concepts include a method of, and program product for, optimizing an illumination profile of a pattern to be formed in a surface of a substrate relative to a given mask. Steps include mathematically representing resolvable feature(s) from the given mask, generating an interference map representation from the previous step, modifying the interference map representation to maximize intensity corresponding to the resolvable features, and determining assist feature size(s) such that intensity side lobes do not print.
    Type: Application
    Filed: October 29, 2004
    Publication date: June 30, 2005
    Inventors: Robert Socha, Xuelong Shi, Douglas Broeke, Jang Chen
  • Publication number: 20050053848
    Abstract: Disclosed concepts include a method, program product and apparatus for generating assist features for a pattern to be formed on the surface of a substrate by generating an image field map corresponding to the pattern. Characteristics are extracted from the image field map, and assist features are generated for the pattern in accordance with the characteristics extracted in step. The assist features may be oriented relative to a dominant axis of a contour of the image field map. Also, the assist features may be polygon-shaped and sized to surround the contour or relative to the inside of the contour. Moreover, the assist features may be placed in accordance with extrema identified from the image field map. Utilizing the image field map, a conventional and complex two-dimensional rules-based approach for generating assist feature can be obviated.
    Type: Application
    Filed: June 29, 2004
    Publication date: March 10, 2005
    Inventors: Kurt Wampler, Douglas Van Den Broeke, Uwe Hollerbach, Xuelong Shi, Jang Chen
  • Publication number: 20050034096
    Abstract: Optical proximity effects (OPEs) are a well-known phenomenon in photolithography. OPEs result from the structural interaction between the main feature and neighboring features. It has been determined by the present inventors that such structural interactions not only affect the critical dimension of the main feature at the image plane, but also the process latitude of the main feature. Moreover, it has been determined that the variation of the critical dimension as well as the process latitude of the main feature is a direct consequence of light field interference between the main feature and the neighboring features. Depending on the phase of the field produced by the neighboring features, the main feature critical dimension and process latitude can be improved by constructive light field interference, or degraded by destructive light field interference. The phase of the field produced by the neighboring features is dependent on the pitch as well as the illumination angle.
    Type: Application
    Filed: September 13, 2004
    Publication date: February 10, 2005
    Applicant: ASML Masktools Netherlands B.V.
    Inventors: Xuelong Shi, Jang Chen, Duan-Fu Hsu
  • Publication number: 20040229133
    Abstract: Disclosed concepts include a method of optimizing an illumination profile of a pattern to be formed in a surface of a substrate. Illumination is optimized by defining a transmission cross coefficient (“TCC”) function determined in accordance with an illumination pupil and a projection pupil corresponding to an illuminator, representing at least one resolvable feature of a mask to be printed on the substrate by at least one impulse function, and creating an interference map of a predetermined order based on the at least one impulse function and the TCC function, wherein the interference map represents the at least one resolvable feature to be printed on the substrate and areas of destructive interference.
    Type: Application
    Filed: January 14, 2004
    Publication date: November 18, 2004
    Inventors: Robert John Socha, Xuelong Shi, Douglas Van Den Broeke, Jang Fung Chen
  • Patent number: 6792591
    Abstract: Optical proximity effects (OPEs) are a well-known phenomenon in photolithography. OPEs result from the structural interaction between the main feature and neighboring features. It has been determined by the present inventors that such structural interactions not only affect the critical dimension of the main feature at the image plane, but also the process latitude of the main feature. Moreover, it has been determined that the variation of the critical dimension as well as the process latitude of the main feature is a direct consequence of light field interference between the main feature and the neighboring features. Depending on the phase of the field produced by the neighboring features, the main feature critical dimension and process latitude can be improved by constructive light field interference, or degraded by destructive light field interference. The phase of the field produced by the neighboring features is dependent on the pitch as well as the illumination angle.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: September 14, 2004
    Assignee: ASML Masktools B.V.
    Inventors: Xuelong Shi, Jang Fung Chen, Duan-Fu Stephen Hsu
  • Publication number: 20040139418
    Abstract: A method of automatically applying optical proximity correction techniques to a reticle design containing a plurality of features. The method comprises the steps of: (1) generating a first set of rules for applying scatter bar assist features to the plurality of features for a given illumination setting; (2) generating a second set of rules for applying biasing to the plurality of features for said given illumination setting; (3) forming a look-up table containing the first set of rules and the second set of rules; and (4) analyzing each of the plurality of features with the first set of rules and the second set of rules contained in the look-up table to determine if either the first set of rules or the second set of rules is applicable to a given feature. If either the first set of rules or the second set of rules is applicable to the given feature, the given feature is modified in accordance with the applicable rule.
    Type: Application
    Filed: July 25, 2003
    Publication date: July 15, 2004
    Inventors: Xuelong Shi, Jang Fung Chen
  • Publication number: 20030082463
    Abstract: A method for generating a photolithography mask for optically transferring a pattern formed in the mask onto a substrate utilizing an imaging system.
    Type: Application
    Filed: October 9, 2002
    Publication date: May 1, 2003
    Inventors: Thomas Laidig, Jang Fung Chen, Xuelong Shi, Ralph Schlief, Uwe Hollerbach, Kurt E. Wampler
  • Patent number: 6519760
    Abstract: Optical proximity effects (OPEs) are a well-known phenomenon in photolithography. OPEs result from the structural interaction between the main feature and neighboring features. It has been determined by the present inventors that such structural interactions not only affect the critical dimension of the main feature at the image plane, but also the process latitude of the main feature. Moreover, it has been determined that the variation of the critical dimension as well as the process latitude of the main feature is a direct consequence of light field interference between the main feature and the neighboring features. Depending on the phase of the field produced by the neighboring features, the main feature critical dimension and process latitude can be improved by constructive light field interference, or degraded by destructive light field interference. The phase of the field produced by the neighboring features is dependent on the pitch as well as the illumination angle.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: February 11, 2003
    Assignee: ASML Masktools, B.V.
    Inventors: Xuelong Shi, Jang Fung Chen, Stephen Hsu
  • Publication number: 20020157081
    Abstract: Optical proximity effects (OPEs) are a well-known phenomenon in photolithography. OPEs result from the structural interaction between the main feature and neighboring features. It has been determined by the present inventors that such structural interactions not only affect the critical dimension of the main feature at the image plane, but also the process latitude of the main feature. Moreover, it has been determined that the variation of the critical dimension as well as the process latitude of the main feature is a direct consequence of light field interference between the main feature and the neighboring features. Depending on the phase of the field produced by the neighboring features, the main feature critical dimension and process latitude can be improved by constructive light field interference, or degraded by destructive light field interference. The phase of the field produced by the neighboring features is dependent on the pitch as well as the illumination angle.
    Type: Application
    Filed: February 27, 2002
    Publication date: October 24, 2002
    Inventors: Xuelong Shi, Jang Fung Chen, Duan-Fu Stephen Hsu
  • Publication number: 20020152451
    Abstract: Optical proximity effects (OPEs) are a well-known phenomenon in photolithography. OPEs result from the structural interaction between the main feature and neighboring features. It has been determined by the present inventors that such structural interactions not only affect the critical dimension of the main feature at the image plane, but also the process latitude of the main feature. Moreover, it has been determined that the variation of the critical dimension as well as the process latitude of the main feature is a direct consequence of light field interference between the main feature and the neighboring features. Depending on the phase of the field produced by the neighboring features, the main feature critical dimension and process latitude can be improved by constructive light field interference, or degraded by destructive light field interference. The phase of the field produced by the neighboring features is dependent on the pitch as well as the illumination angle.
    Type: Application
    Filed: April 24, 2001
    Publication date: October 17, 2002
    Inventors: Xuelong Shi, Jang Fung Chen, Stephen Hsu
  • Patent number: 6245491
    Abstract: Acid diffusion induced critical dimension change in a chemically amplified photoresist process is suppressed by lowering the reaction activation energy barrier. Energy required to overcome the reaction activation energy barrier is provided directly to the chemical bonds that are involved in the chemical reactions, rather than providing energy solely by thermal heating, thereby significantly increasing reaction rate without increasing acid diffusion.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: June 12, 2001
    Assignee: National Semiconductor Corp.
    Inventor: Xuelong Shi
  • Patent number: 6100012
    Abstract: A photolithographic process for use in semiconductor device manufacturing that includes an infrared radiation-based post exposure bake (PEB) of a chemically amplified resist layer and that improves critical dimension control of a patterned resist layer. The use of infrared radiation with a wavenumber that is preferentially absorbed in the DUV-exposed regions of the chemically amplified resist selectively increases the temperature of the DUV-exposed regions, while maintaining the temperature in the DUV-unexposed regions relatively low. The increased temperature initiates and accelerates acid catalyzed chemical transformation of the resist polymer in the DUV-exposed regions. The lower temperature in the DUV-unexposed regions suppresses the diffusion/migration of acid catalyst into those regions from the DUV-exposed regions.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: August 8, 2000
    Assignee: National Semiconductor Corporation
    Inventor: Xuelong Shi