Patents by Inventor Stanley E. Stokowski

Stanley E. Stokowski 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: 9886764
    Abstract: The invention relates to an image acquisition system and an image acquisition method, as well as to an inspection system having at least one such image acquisition system. A projector projects a pattern on a surface of a sample, a camera records light intensity information from within at least two detection fields defined by the camera on the surface of the sample. A relative motion between the sample on the one hand and the camera and projector on the other hand is generated. From the acquired at least one image a height profile of the surface of the sample may be inferred. The pattern may comprise a number of sub-patterns related to each other by a phase shift. Alternatively, the pattern may be a fringe pattern.
    Type: Grant
    Filed: October 29, 2015
    Date of Patent: February 6, 2018
    Assignee: KLA-Tencor Corporation
    Inventors: Guoheng Zhao, Stanley E. Stokowski, Andrew Hill, Johan De Greeve, Maarten Van Der Burgt, Karel Van Gils
  • Patent number: 9679372
    Abstract: Disclosed are methods and apparatus for inspecting an extreme ultraviolet (EUV) reticle is disclosed. An inspection tool for detecting electromagnetic waveforms is used to obtain a phase defect map for the EUV reticle before a pattern is formed on the EUV reticle, and the phase defect map identifies a position of each phase defect on the EUV reticle. After the pattern is formed on the EUV reticle, a charged particle tool is used to obtain an image of each reticle portion that is proximate to each position of each phase defect as identified in the phase defect map. The phase defect map and one or images of each reticle portion that is proximate to each position of each phase defect are displayed or stored so as to facilitate analysis of whether to repair or discard the EUV reticle.
    Type: Grant
    Filed: January 7, 2015
    Date of Patent: June 13, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Stanley E. Stokowski, Mehdi Vaez-Iravani
  • Patent number: 9645097
    Abstract: Disclosed are methods and apparatus for inspecting and processing semiconductor wafers. The system includes an edge detection system for receiving each wafer that is to undergo a photolithography process. The edge detection system comprises an illumination channel for directing one or more illumination beams towards a side, top, and bottom edge portion that are within a border region of the wafer. The edge detection system also includes a collection module for collecting and sensing output radiation that is scattered or reflected from the edge portion of the wafer and an analyzer module for locating defects in the edge portion and determining whether each wafer is within specification based on the sensed output radiation for such wafer. The photolithography system is configured for receiving from the edge detection system each wafer that has been found to be within specification. The edge detection system is coupled in-line with the photolithography system.
    Type: Grant
    Filed: June 17, 2015
    Date of Patent: May 9, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Lena Nicolaides, Ben-ming Benjamin Tsai, Prashant A. Aji, Michael Gasvoda, Stanley E. Stokowski, Guoheng Zhao, Youxian Wen, Mohan Mahadevan, Paul D. Horn, Wolfgang Vollrath, Isabella T. Lewis
  • Patent number: 9619878
    Abstract: Optical inspection methods and apparatus for high-resolution photomasks using only a test image. A filter is applied to an image signal received from radiation that is transmitted by or reflected from a photomask having a test image. The filter may be implemented using programmed control to adjust and control filter conditions, illumination conditions, and magnification conditions.
    Type: Grant
    Filed: April 11, 2014
    Date of Patent: April 11, 2017
    Assignee: KLA-Tencor Corporation
    Inventors: Fred Stanke, Ilya Toytman, David Alles, Gregg Anthony Inderhees, Stanley E. Stokowski, Mehdi Vaez-Iravani
  • Publication number: 20160048969
    Abstract: The invention relates to an image acquisition system and an image acquisition method, as well as to an inspection system having at least one such image acquisition system. A projector projects a pattern on a surface of a sample, a camera records light intensity information from within at least two detection fields defined by the camera on the surface of the sample. A relative motion between the sample on the one hand and the camera and projector on the other hand is generated. From the acquired at least one image a height profile of the surface of the sample may be inferred. The pattern may comprise a number of sub-patterns related to each other by a phase shift. Alternatively, the pattern may be a fringe pattern.
    Type: Application
    Filed: October 29, 2015
    Publication date: February 18, 2016
    Inventors: Guoheng ZHAO, Stanley E. Stokowski, Andrew HILL, Johan DE GREEVE, Maarten VAN DER BURGT, Karel VAN GILS
  • Publication number: 20150370175
    Abstract: Disclosed are methods and apparatus for inspecting and processing semiconductor wafers. The system includes an edge detection system for receiving each wafer that is to undergo a photolithography process. The edge detection system comprises an illumination channel for directing one or more illumination beams towards a side, top, and bottom edge portion that are within a border region of the wafer. The edge detection system also includes a collection module for collecting and sensing output radiation that is scattered or reflected from the edge portion of the wafer and an analyzer module for locating defects in the edge portion and determining whether each wafer is within specification based on the sensed output radiation for such wafer. The photolithography system is configured for receiving from the edge detection system each wafer that has been found to be within specification. The edge detection system is coupled in-line with the photolithography system.
    Type: Application
    Filed: June 17, 2015
    Publication date: December 24, 2015
    Applicant: KLA-Tencor Corporation
    Inventors: Lena Nicolaides, Ben-ming Benjamin Tsai, Prashant A. Aji, Michael Gasvoda, Stanley E. Stokowski, Guoheng Zhao, Youxian Wen, Mohan Mahadevan, Paul D. Horn, Wolfgang Vollrath, Isabella T. Lewis
  • Publication number: 20150117754
    Abstract: Disclosed are methods and apparatus for inspecting an extreme ultraviolet (EUV) reticle is disclosed. An inspection tool for detecting electromagnetic waveforms is used to obtain a phase defect map for the EUV reticle before a pattern is formed on the EUV reticle, and the phase defect map identifies a position of each phase defect on the EUV reticle. After the pattern is formed on the EUV reticle, a charged particle tool is used to obtain an image of each reticle portion that is proximate to each position of each phase defect as identified in the phase defect map. The phase defect map and one or images of each reticle portion that is proximate to each position of each phase defect are displayed or stored so as to facilitate analysis of whether to repair or discard the EUV reticle.
    Type: Application
    Filed: January 7, 2015
    Publication date: April 30, 2015
    Applicant: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Stanley E. Stokowski, Mehdi Vaez-Iravani
  • Patent number: 8953869
    Abstract: Disclosed are methods and apparatus for inspecting an extreme ultraviolet (EUV) reticle is disclosed. An optical inspection tool is used to obtain a phase defect map for the EUV reticle before a pattern is formed on the EUV reticle, and the phase defect map identifies a position of each phase defect on the EUV reticle. After the pattern is formed on the EUV reticle, a charged particle tool is used to obtain an image of each reticle portion that is proximate to each position of each phase defect as identified in the phase defect map. The phase defect map and one or images of each reticle portion that is proximate to each position of each phase defect are displayed or stored so as to facilitate analysis of whether to repair or discard the EUV reticle.
    Type: Grant
    Filed: May 30, 2013
    Date of Patent: February 10, 2015
    Assignee: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Stanley E. Stokowski, Mehdi Vaez-Iravani
  • Publication number: 20140307943
    Abstract: Optical inspection methods and apparatus for high-resolution photomasks using only a test image. A filter is applied to an image signal received from radiation that is transmitted by or reflected from a photomask having a test image. The filter may be implemented using programmed control to adjust and control filter conditions, illumination conditions, and magnification conditions.
    Type: Application
    Filed: April 11, 2014
    Publication date: October 16, 2014
    Applicant: KLA-Tencor Corporation
    Inventors: Fred Stanke, Ilya Toytman, David Alles, Gregg Anthony Inderhees, Stanley E. Stokowski, Mehdi Vaez-Iravani
  • Patent number: 8785082
    Abstract: An EUV integrated circuit fabrication method and system EUV that includes blank inspection, defect characterization, simulation, pattern compensation, modification of the mask writer database, inspection and simulation of patterned masks, and patterned mask repair. The system performs blank inspection to identify defects at multiple focal planes within the blank. The mask can be relocated on the blank and alterations to the pattern can be developed to compensate for the defects prior to prior to patterning the mask. Once the mask has been patterned, the reticle is inspected to identify any additional or remaining defects that were not picked up during blank inspection or fully mitigated through pattern compensation. The patterned reticle can then be repaired prior to integrated circuit fabrication.
    Type: Grant
    Filed: March 12, 2012
    Date of Patent: July 22, 2014
    Assignee: KLA-Tencor Corporation
    Inventors: Yalin Xiong, Stanley E. Stokowski
  • Patent number: 8711346
    Abstract: Provided are novel inspection methods and systems for inspecting unpatterned objects, such as extreme ultraviolet (EUV) mask blanks, for surface defects, including extremely small defects. Defects may include various phase objects, such as bumps and pits that are only about 1 nanometer in height, and small particles. Inspection is performed at wavelengths less than about 250 nanometers, such as a reconfigured deep UV inspection system. A partial coherence sigma is set to between about 0.15 and 0.5. Phase defects can be found by using one or more defocused inspection passes, for example at one positive depth of focus (DOF) and one negative DOF. In certain embodiments, DOF is between about ?1 to ?3 and/or +1 to +3. The results of multiple inspection passes can be combined to differentiate defect types. Inspection methods may involve applying matched filters, thresholds, and/or correction factors in order to improve a signal to noise ratio.
    Type: Grant
    Filed: June 10, 2010
    Date of Patent: April 29, 2014
    Assignee: KLA-Tencor Corporation
    Inventor: Stanley E. Stokowski
  • Publication number: 20130336574
    Abstract: Disclosed are methods and apparatus for inspecting an extreme ultraviolet (EUV) reticle is disclosed. An optical inspection tool is used to obtain a phase defect map for the EUV reticle before a pattern is formed on the EUV reticle, and the phase defect map identifies a position of each phase defect on the EUV reticle. After the pattern is formed on the EUV reticle, a charged particle tool is used to obtain an image of each reticle portion that is proximate to each position of each phase defect as identified in the phase defect map. The phase defect map and one or images of each reticle portion that is proximate to each position of each phase defect are displayed or stored so as to facilitate analysis of whether to repair or discard the EUV reticle.
    Type: Application
    Filed: May 30, 2013
    Publication date: December 19, 2013
    Inventors: Mehran Nasser-Ghodsi, Stanley E. Stokowski, Mehdi Vaez-Iravani
  • Publication number: 20120238096
    Abstract: An EUV integrated circuit fabrication method and system EUV that includes blank inspection, defect characterization, simulation, pattern compensation, modification of the mask writer database, inspection and simulation of patterned masks, and patterned mask repair. The system performs blank inspection to identify defects at multiple focal planes within the blank. The mask can be relocated on the blank and alterations to the pattern can be developed to compensate for the defects prior to prior to patterning the mask. Once the mask has been patterned, the reticle is inspected to identify any additional or remaining defects that were not picked up during blank inspection or fully mitigated through pattern compensation. The patterned reticle can then be repaired prior to integrated circuit fabrication.
    Type: Application
    Filed: March 12, 2012
    Publication date: September 20, 2012
    Applicant: KLA-TENCOR CORPORATION
    Inventors: Yalin Xiong, Stanley E. Stokowski
  • Publication number: 20110181868
    Abstract: Provided are novel inspection methods and systems for inspecting unpatterned objects, such as extreme ultraviolet (EUV) mask blanks, for surface defects, including extremely small defects. Defects may include various phase objects, such as bumps and pits that are only about 1 nanometer in height, and small particles. Inspection is performed at wavelengths less than about 250 nanometers, such as a reconfigured deep UV inspection system. A partial coherence sigma is set to between about 0.15 and 0.5. Phase defects can be found by using one or more defocused inspection passes, for example at one positive depth of focus (DOF) and one negative DOF. In certain embodiments, DOF is between about ?1 to ?3 and/or +1 to +3. The results of multiple inspection passes can be combined to differentiate defect types. Inspection methods may involve applying matched filters, thresholds, and/or correction factors in order to improve a signal to noise ratio.
    Type: Application
    Filed: June 10, 2010
    Publication date: July 28, 2011
    Applicant: KLA - TENCOR TECHNOLOGIES CORPORATION
    Inventor: Stanley E. Stokowski
  • Patent number: 7564545
    Abstract: Disclosed are apparatus and methods for finding lithographically significant defects on a reticle. In general, at least a pair of related intensity images of the reticle in question are obtained using an inspection apparatus. The intensity images are obtained such that each of the images experience different focus settings for the reticle so that there is a constant focus offset between the two focus values of the images. These images are then analyzed to obtain a transmission function of the reticle. This transmission function is then input into a model of the lithography system (e.g., a stepper, scanner, or other related photolithography system) to then produce an aerial image of the reticle pattern. The aerial image produced can then be input to a photoresist model to yield a “resist-modeled image” that corresponds to an image pattern to be printed onto the substrate using the reticle. This resist-modeled image can then be compared with a reference image to obtain defect information.
    Type: Grant
    Filed: March 15, 2007
    Date of Patent: July 21, 2009
    Assignee: KLA-Tencor Technologies Corp.
    Inventor: Stanley E. Stokowski
  • Publication number: 20080226157
    Abstract: Disclosed are apparatus and methods for finding lithographically significant defects on a reticle. In general, at least a pair of related intensity images of the reticle in question are obtained using an inspection apparatus. The intensity images are obtained such that each of the images experience different focus settings for the reticle so that there is a constant focus offset between the two focus values of the images. These images are then analyzed to obtain a transmission function of the reticle. This transmission function is then input into a model of the lithography system (e.g., a stepper, scanner, or other related photolithography system) to then produce an aerial image of the reticle pattern. The aerial image produced can then be input to a photoresist model to yield a “resist-modeled image” that corresponds to an image pattern to be printed onto the substrate using the reticle. This resist-modeled image can then be compared with a reference image to obtain defect information.
    Type: Application
    Filed: March 15, 2007
    Publication date: September 18, 2008
    Inventor: Stanley E. Stokowski
  • Publication number: 20080218747
    Abstract: An optical system and method configured to detect surface height variations on a mask blank. The optical system comprises a Wollaston prism, optics and first and second detectors. The Wollaston prism splits an incident beam of radiation into a first beam and a second beam. The first beam has a first polarization. The second beam has a second polarization. The optics directs the first and second beams along first and second paths onto first and second illuminated areas on a surface of the mask blank. The first and second illuminated areas reflect or transmit portions of the first and second beams to produce first and second reflected or transmitted beams. The first and second detectors detect the first and second reflected or transmitted beams and produce first and second signals in response to the first and second reflected or transmitted beams. A multiple way coupler may also be used for detecting height variation or other features on a mask blank.
    Type: Application
    Filed: May 23, 2008
    Publication date: September 11, 2008
    Inventor: Stanley E. Stokowski
  • Patent number: 7319229
    Abstract: Disclosed are apparatus and methods for illuminating a sample, e.g., during an inspection of such sample for defects. In one aspect, the illumination apparatus includes a bundle of fibers that each has a first end and a second end. The illumination apparatus further includes an illumination selector for selectively transmitting one or more incident beams into one or more corresponding first ends of the optical fibers so that the selected one or more incident beams are output from one or more corresponding second ends of the fibers. The illumination apparatus also includes a lens arrangement for receiving the selected one or more incidents beams output from the corresponding one or more second ends of the fibers and directing the selected one or more incident beams towards the sample. The lens arrangement and the fibers are arranged with respect to each other so as to image an imaging plane of the sample at the second ends of the fibers. In one aspect, the incident beams are laser beams.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: January 15, 2008
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Mehdi Vaez-Iravani, Guoheng Zhao, Stanley E. Stokowski
  • Patent number: 7303842
    Abstract: Disclosed are systems and methods for modifying a reticle. In general, inspection results from a plurality of wafers or prediction results from a lithographic model are used to individually decrease the dose or any other optical property at specific locations of the reticle. In one embodiment, any suitable optical property of the reticle is modified by an optical beam, such as a femto-second laser, at specific locations on the reticle so as to widen the process window for such optical property. Examples of optical properties include dose, phase, illumination angle, and birefringence. Techniques for adjusting optical properties at specific locations on a reticle using an optical beam may be practiced for other purposes besides widening the process window.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: December 4, 2007
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Sterling G. Watson, Ady Levy, Chris A. Mack, Stanley E. Stokowski, Zain K. Saidin, Larry S. Zurbrick
  • Patent number: 7300725
    Abstract: Disclosed are techniques for determining and correcting reticle variations using a reticle global variation map generated by comparing a set of measured reticle parameters to a set of reference reticle parameters. The measured reticle parameters are obtained by reticle inspection, and the variation map identifies reticle regions and associated levels of correction. In one embodiment, the variation data is communicated to a system which modifies the reticle by embedding scattering centers within the reticle at identified reticle regions, thereby improving the variations. In another embodiment the variation data is transferred to a wafer stepper or scanner which in turn modifies the conditions under which the reticle is used to manufacture wafers, thereby compensating for the variations and producing wafers that are according to design.
    Type: Grant
    Filed: March 29, 2006
    Date of Patent: November 27, 2007
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Sterling G. Watson, Ady Levy, Chris A. Mack, Stanley E. Stokowski, Zain K. Saidin