Patents by Inventor David Tien

David Tien 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: 10725385
    Abstract: A method may include, but is not limited to, receiving a measurement including a metrology parameter for a layer of a metrology target and an alignment mark from an overlay metrology tool prior to a lithography process; deriving a merit figure from the metrology parameter and the alignment mark; deriving a correction factor from the merit figure; providing the correction factor to the lithography process via a feed forward process; receiving an additional measurement including an additional metrology parameter for the layer and an additional layer from an additional overlay metrology tool after the lithography process; deriving an adjustment from the additional metrology parameter; and providing the adjustment to the lithography process via a feedback process.
    Type: Grant
    Filed: August 10, 2018
    Date of Patent: July 28, 2020
    Assignee: KLA-Tencor Corporation
    Inventors: Tsachy Holovinger, Liran Yerushalmi, David Tien, DongSub Choi
  • Patent number: 10295993
    Abstract: The invention may be embodied in a system and method for monitoring and controlling feedback control in a manufacturing process, such as an integrated circuit fabrication process. The process control parameters may include translation, rotation, magnification, dose and focus applied by a photolithographic scanner or stepper operating on silicon wafers. Overlay errors are used to compute measured parameters used in the feedback control process. Statistical parameters are computed, normalized and graphed on a common set of axes for at-a-glance comparison of measured parameters and process control parameters to facilitate the detection of problematic parameters. Parameter trends and context relaxation scenarios are also compared graphically. Feedback control parameters, such as EWMA lambdas, may be determined and used as feedback parameters for refining the APC model that computes adjustments to the process control parameters based on the measured parameters.
    Type: Grant
    Filed: August 29, 2012
    Date of Patent: May 21, 2019
    Assignee: KLA-Tencor Corporation
    Inventors: Dongsub Choi, David Tien
  • Publication number: 20180348649
    Abstract: A method may include, but is not limited to, receiving a measurement including a metrology parameter for a layer of a metrology target and an alignment mark from an overlay metrology tool prior to a lithography process; deriving a merit figure from the metrology parameter and the alignment mark; deriving a correction factor from the merit figure; providing the correction factor to the lithography process via a feed forward process; receiving an additional measurement including an additional metrology parameter for the layer and an additional layer from an additional overlay metrology tool after the lithography process; deriving an adjustment from the additional metrology parameter; and providing the adjustment to the lithography process via a feedback process.
    Type: Application
    Filed: August 10, 2018
    Publication date: December 6, 2018
    Inventors: Tsachy Holovinger, Liran Yerushalmi, David Tien, DongSub Choi
  • Patent number: 10095121
    Abstract: Methods and corresponding metrology modules and systems, which measure metrology parameter(s) of a previous layer of a metrology target and/or an alignment mark, prior to producing a current layer of the metrology target, derive merit figure(s) from the measured metrology parameter(s) to indicate an inaccuracy, and compensate for the inaccuracy to enhance subsequent overlay measurements of the metrology target. In an example embodiment, methods and corresponding metrology modules and systems use stand-alone metrology tool(s) and track-integrated metrology tool(s) at distinct measurement patterns to address separately different aspects of variation among wafers.
    Type: Grant
    Filed: January 20, 2016
    Date of Patent: October 9, 2018
    Assignee: KLA-Tencor Corporation
    Inventors: Tsachy Holovinger, Liran Yerushalmi, David Tien, DongSub Choi
  • Patent number: 9709903
    Abstract: An overlay target for use in imaging based metrology is disclosed. The overlay target includes a plurality of target structures including three or more target structures, each target structure including a set of two or more pattern elements, wherein the target structures are configured to provide metrology information pertaining to different pitches, different coverage ratios, and linearity. Pattern elements may be separated from adjacent pattern elements by non-uniform distance; pattern elements may have non-uniform width; or pattern elements may be designed to demonstrate a specific offset as compared to pattern elements in a different layer.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: July 18, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: DongSub Choi, David Tien
  • Patent number: 9476838
    Abstract: Metrology targets, design files, and design and production methods thereof are provided. The metrology targets are hybrid in that they comprise at least one imaging target structure configured to be measurable by imaging and at least one scatterometry target structure configured to be measurable by scatterometry. Thus, the hybrid targets may be measured by imaging and scatterometry simultaneously or alternatingly and/or the measurement techniques may be optimized with respect to wafer regions and other spatial parameters, as well as with respect to temporal process parameters. The hybrid targets may be used to monitor process parameters, for example via comparative overlay measurements and/or high resolution measurements.
    Type: Grant
    Filed: July 22, 2014
    Date of Patent: October 25, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: DongSub Choi, Tal Itzkovich, David Tien
  • Patent number: 9466100
    Abstract: A method for monitoring mask focus includes measuring profile asymmetries in a target feature including sub-resolution assist features and deriving a focus response based on a known correlation between the profile and focus of a corresponding mask. A computer system in a lithographic process may adjust mask focus based on such derived information to conform to a desired fabrication process.
    Type: Grant
    Filed: June 3, 2013
    Date of Patent: October 11, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: DongSub Choi, Bill Pierson, David Tien, James Manka, Dongsuk Park
  • Publication number: 20160131983
    Abstract: Methods and corresponding metrology modules and systems, which measure metrology parameter(s) of a previous layer of a metrology target and/or an alignment mark, prior to producing a current layer of the metrology target, derive merit figure(s) from the measured metrology parameter(s) to indicate an inaccuracy, and compensate for the inaccuracy to enhance subsequent overlay measurements of the metrology target. In an example embodiment, methods and corresponding metrology modules and systems use stand-alone metrology tool(s) and track-integrated metrology tool(s) at distinct measurement patterns to address separately different aspects of variation among wafers.
    Type: Application
    Filed: January 20, 2016
    Publication date: May 12, 2016
    Inventors: Tsachy Holovinger, Liran Yerushalmi, David Tien, DongSub Choi
  • Patent number: 9291920
    Abstract: The present disclosure is directed to a method of determining one or more focus values for a lithographic scanner. An optical signal including at least a first variable and a second variable is detected by an optical analysis system from at least one test sample for a plurality of programmed focus error values. A first variable value showing sensitivity to focus is selected based upon a corresponding responsiveness of the second variable to change of focus and/or a corresponding linearity of raw focus with respect to the programmed focus error. At least one focus value for the lithographic scanner is determined based upon at least one determined raw focus value corresponding to the selected first variable value.
    Type: Grant
    Filed: August 30, 2013
    Date of Patent: March 22, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: James Manka, David Tien, Christian Sparka
  • Publication number: 20140375984
    Abstract: Metrology targets, design files, and design and production methods thereof are provided. The metrology targets are hybrid in that they comprise at least one imaging target structure configured to be measurable by imaging and at least one scatterometry target structure configured to be measurable by scatterometry. Thus, the hybrid targets may be measured by imaging and scatterometry simultaneously or alternatingly and/or the measurement techniques may be optimized with respect to wafer regions and other spatial parameters, as well as with respect to temporal process parameters. The hybrid targets may be used to monitor process parameters, for example via comparative overlay measurements and/or high resolution measurements.
    Type: Application
    Filed: July 22, 2014
    Publication date: December 25, 2014
    Inventors: DongSub Choi, Tal Itzkovich, David Tien
  • Publication number: 20140063478
    Abstract: The present disclosure is directed to a method of determining one or more focus values for a lithographic scanner. According to an embodiment, an optical signal including at least a first variable and a second variable is detected by a optical analysis system from at least one test sample for a plurality of programmed focus error values. A first variable value showing sensitivity to focus is selected based upon a corresponding responsiveness of the second variable to change of focus and/or a corresponding linearity of raw focus with respect to the programmed focus error. At least one focus value for the lithographic scanner is determined based upon at least one determined raw focus value corresponding to the selected first variable value.
    Type: Application
    Filed: August 30, 2013
    Publication date: March 6, 2014
    Applicant: KLA-Tencor Corporation
    Inventors: James Manka, David Tien, Christian Sparka
  • Patent number: 8655469
    Abstract: A method for automatic process control (APC) performance monitoring may include, but is not limited to: computing one or more APC performance indicators for one or more production lots of semiconductor devices; and displaying a mapping of the one or more APC performance indicators to the one or more production lots of semiconductor devices.
    Type: Grant
    Filed: June 9, 2011
    Date of Patent: February 18, 2014
    Assignee: KLA-Tencor Corporation
    Inventors: DongSub Choi, Amir Widmann, Daniel Kandel, David Tien
  • Publication number: 20130336572
    Abstract: A method for monitoring mask focus includes measuring profile asymmetries in a target feature including sub-resolution assist features and deriving a focus response based on a known correlation between the profile and focus of a corresponding mask. A computer system in a lithographic process may adjust mask focus based on such derived information to conform to a desired fabrication process.
    Type: Application
    Filed: June 3, 2013
    Publication date: December 19, 2013
    Inventors: DongSub Choi, Bill Pierson, David Tien, James Manka, Dongsuk Park
  • Publication number: 20130107259
    Abstract: An overlay target for use in imaging based metrology is disclosed. The overlay target includes a plurality of target structures including three or more target structures, each target structure including a set of two or more pattern elements, wherein the target structures are configured to provide metrology information pertaining to different pitches, different coverage ratios, and linearity. Pattern elements may be separated from adjacent pattern elements by non-uniform distance; pattern elements may have non-uniform width; or pattern elements may be designed to demonstrate a specific offset as compared to pattern elements in a different layer.
    Type: Application
    Filed: April 13, 2012
    Publication date: May 2, 2013
    Applicant: KLA-Tencor Corporation
    Inventors: Dongsub Choi, David Tien
  • Publication number: 20130060354
    Abstract: The invention may be embodied in a system and method for monitoring and controlling feedback control in a manufacturing process, such as an integrated circuit fabrication process. The process control parameters may include translation, rotation, magnification, dose and focus applied by a photolithographic scanner or stepper operating on silicon wafers. Overlay errors are used to compute measured parameters used in the feedback control process. Statistical parameters are computed, normalized and graphed on a common set of axes for at-a-glance comparison of measured parameters and process control parameters to facilitate the detection of problematic parameters. Parameter trends and context relaxation scenarios are also compared graphically. Feedback control parameters, such as EWMA lambdas, may be determined and used as feedback parameters for refining the APC model that computes adjustments to the process control parameters based on the measured parameters.
    Type: Application
    Filed: August 29, 2012
    Publication date: March 7, 2013
    Applicant: KLA-TENCOR CORPORATION
    Inventors: Dongsub Choi, David Tien
  • Publication number: 20120022679
    Abstract: A method for automatic process control (APC) performance monitoring may include, but is not limited to: computing one or more APC performance indicators for one or more production lots of semiconductor devices; and displaying a mapping of the one or more APC performance indicators to the one or more production lots of semiconductor devices.
    Type: Application
    Filed: June 9, 2011
    Publication date: January 26, 2012
    Applicant: KLA-TENCOR CORPORATION
    Inventors: DongSub Choi, Amir Widmann, Daniel Kandel, David Tien
  • Publication number: 20060242313
    Abstract: Packets received over a network are routed using a packet engine of the invention based on information contained in layer 4 or above. The information for switching is contained in the header information of the packet. Based on this higher level information, the packet engine may drop the packet, redirect the packet, load balance the packet, perform bandwidth provisioning (e.g., limit the speed of a connection), or adjust quality of service (e.g., change priority or rearrange a queue of packets to be handled), or combinations of these.
    Type: Application
    Filed: June 7, 2006
    Publication date: October 26, 2006
    Applicant: LeWiz Communications
    Inventors: Chinh Le, David Tien, Thanh Truong
  • Patent number: 6978535
    Abstract: A pressing device for thin-film circuits and terminals includes the characteristics of a machine base provided with a bottom panel, and a cutting block and a pressing block capable of intermittent up-and-down displacement at an interior thereof; an inner modular base capable of elastic displacement and flexibly disposed in a projecting column on the bottom panel; and an outer modular base fixed at an outer side of the inner modular base. Wherein, the outer modular base presses onto an upper pressing plane using downward displacement of the pressing block, and a cutting-edge portion slides upward along a rear sliding wall of the inner modular base, thereby accurately puncturing, stamping and connecting a plurality of terminals onto silvered wires of a thin-film circuit at a time.
    Type: Grant
    Filed: May 12, 2003
    Date of Patent: December 27, 2005
    Inventor: David Tien
  • Publication number: 20040226168
    Abstract: A pressing device for thin-film circuits and terminals includes the characteristics of a machine base provided with a bottom panel, and a cutting block and a pressing block capable of intermittent up-and-down displacement at an interior thereof; an inner modular base capable of elastic displacement and flexibly disposed in a projecting column on the bottom panel; and an outer modular base fixed at an outer side of the inner modular base. Wherein, the outer modular base presses onto an upper pressing plane using downward displacement of the pressing block, and a cutting-edge portion slides upward along a rear sliding wall of the inner modular base, thereby accurately puncturing, stamping and connecting a plurality of terminals onto silvered wires of a thin-film circuit at a time.
    Type: Application
    Filed: May 12, 2003
    Publication date: November 18, 2004
    Inventor: David Tien