Patents by Inventor Daniel Kavaldjiev
Daniel Kavaldjiev 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).
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Patent number: 11733172Abstract: A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.Type: GrantFiled: May 6, 2021Date of Patent: August 22, 2023Assignee: KLA CorporationInventors: Anatoly Romanovsky, Jenn-Kuen Leong, Daniel Kavaldjiev, Chunhai Wang, Bret Whiteside, Zhiwei Xu
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Patent number: 11441893Abstract: A system for analyzing a sample includes an illumination source with a plurality of transmitting optical fibers optically coupled to the illumination source and a detector with a plurality of receiving optical fibers optically coupled to the detector. The system further includes a plurality of probes coupled to respective ones of the plurality of transmitting optical fibers and respective ones of the plurality of receiving optical fibers. The plurality of probes are configured to illuminate respective portions of a surface of the sample and configured to receive illumination reflected, refracted, or radiated from the respective portions of the surface of the sample. The system may further include one or more switches and/or splitters configured to optically couple respective ones of the plurality of transmitting optical fibers to the illumination source and/or configured to optically couple respective ones of the plurality of receiving optical fibers to the detector.Type: GrantFiled: June 26, 2018Date of Patent: September 13, 2022Assignee: KLA CorporationInventors: Prasanna Dighe, Dieter Mueller, Dong Chen, Dengpeng Chen, Steve Zamek, Daniel Kavaldjiev, Alexander Buettner
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Patent number: 11243175Abstract: A system may include illumination optics to direct an illumination beam to a sample at an off-axis angle, collection optics to collect scattered light from the sample, and a phase mask located at a first pupil plane to provide different phase shifts for light in two or more pupil regions of a collection area to reshape a point spread function of light scattered from one or more particles on a surface of the sample. The system may further include a polarization rotator located at a second pupil plane, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from the surface of the sample to a selected polarization angle, a polarizer to reject light polarized along the selected polarization angle, and a detector to generate a dark-field image of the sample based on light passed by the polarizer.Type: GrantFiled: February 12, 2021Date of Patent: February 8, 2022Assignee: KLA CorporationInventors: Xuefeng Liu, Jenn-Kuen Leong, Daniel Kavaldjiev, John Fielden
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Publication number: 20210356406Abstract: A dark-field optical system may include a rotational objective lens assembly with a dark-field objective lens to collect light from a sample within a collection numerical aperture, where the dark-field objective lens includes an entrance aperture and an exit aperture at symmetrically-opposed azimuth angles with respect to an optical axis, a rotational bearing to allow rotation of at least a part of the dark-field objective lens including the entrance aperture and the exit aperture around the optical axis, and a rotational driver to control a rotational angle of the entrance aperture. The system may also include a multi-angle illumination sub-system to illuminate the sample with an illumination beam through the entrance aperture at two or more illumination azimuth angles, where an azimuth angle of the illumination beam on the sample is selectable by rotating the objective lens to any of the two or more illumination azimuth angles.Type: ApplicationFiled: May 6, 2021Publication date: November 18, 2021Inventors: Anatoly Romanovsky, Jenn-Kuen Leong, Daniel Kavaldjiev, Chunhai Wang, Bret Whiteside, Steve Xu
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Publication number: 20210164918Abstract: A system may include illumination optics to direct an illumination beam to a sample at an off-axis angle, collection optics to collect scattered light from the sample, and a phase mask located at a first pupil plane to provide different phase shifts for light in two or more pupil regions of a collection area to reshape a point spread function of light scattered from one or more particles on a surface of the sample. The system may further include a polarization rotator located at a second pupil plane, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from the surface of the sample to a selected polarization angle, a polarizer to reject light polarized along the selected polarization angle, and a detector to generate a dark-field image of the sample based on light passed by the polarizer.Type: ApplicationFiled: February 12, 2021Publication date: June 3, 2021Applicant: KLA CorporationInventors: Xuefeng Liu, Jenn-Kuen Leong, Daniel Kavaldjiev, John Fielden
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Patent number: 10948423Abstract: A dark-field inspection system may include an illumination source to generate an illumination beam, illumination optics configured to direct the illumination beam to a sample at an off-axis angle along an illumination direction, collection optics to collect scattered light from the sample in response to the illumination beam in a dark-field mode, a polarization rotator located at a pupil plane of the one or more collection optics, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from a surface of the sample to a selected polarization angle, a polarizer aligned to reject light polarized along the selected polarization angle to reject the light scattered from a surface of the sample, and a detector to generate a dark-field image of the sample based on scattered light from the sample passed by the polarizer.Type: GrantFiled: September 20, 2019Date of Patent: March 16, 2021Assignee: KLA CorporationInventors: Xuefeng Liu, Jenn-Kuen Leong, Daniel Kavaldjiev, John Fielden
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Patent number: 10942135Abstract: A dark field inspection system may include an illumination source to generate an illumination beam, one or more illumination optics to direct the illumination beam to a sample at an off-axis angle along an illumination direction, a detector, one or more collection optics to generate a dark-field image of the sample on the detector based on light collected from the sample in response to the illumination beam, and a radial polarizer located at a pupil plane of the one or more collection optics, where the radial polarizer rejects light with radial polarization with respect to an apex point in the pupil plane corresponding to specular reflection of the illumination beam from the sample.Type: GrantFiled: September 20, 2019Date of Patent: March 9, 2021Assignee: KLA CorporationInventors: Jenn-Kuen Leong, Daniel Kavaldjiev, Guoheng Zhao
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Publication number: 20200264109Abstract: A dark-field inspection system may include an illumination source to generate an illumination beam, illumination optics configured to direct the illumination beam to a sample at an off-axis angle along an illumination direction, collection optics to collect scattered light from the sample in response to the illumination beam in a dark-field mode, a polarization rotator located at a pupil plane of the one or more collection optics, where the polarization rotator provides a spatially-varying polarization rotation angle selected to rotate light scattered from a surface of the sample to a selected polarization angle, a polarizer aligned to reject light polarized along the selected polarization angle to reject the light scattered from a surface of the sample, and a detector to generate a dark-field image of the sample based on scattered light from the sample passed by the polarizer.Type: ApplicationFiled: September 20, 2019Publication date: August 20, 2020Inventors: Xuefeng Liu, Jenn-Kuen Leong, Daniel Kavaldjiev, John Fielden
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Publication number: 20200150054Abstract: A dark field inspection system may include an illumination source to generate an illumination beam, one or more illumination optics to direct the illumination beam to a sample at an off-axis angle along an illumination direction, a detector, one or more collection optics to generate a dark-field image of the sample on the detector based on light collected from the sample in response to the illumination beam, and a radial polarizer located at a pupil plane of the one or more collection optics, where the radial polarizer rejects light with radial polarization with respect to a reference point in the pupil plane corresponding to specular reflection of the illumination beam from the sample.Type: ApplicationFiled: September 20, 2019Publication date: May 14, 2020Inventors: Jenn-Kuen Leong, Daniel Kavaldjiev, Guoheng Zhao
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Patent number: 10488348Abstract: Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered light that can be imaged on the entire area of the sensor, and wherein the sensor is configured to generate output responsive to the integrated pulses of scattered light; and a computer subsystem configured to detect defects on the wafer using the output generated by the sensor.Type: GrantFiled: January 29, 2018Date of Patent: November 26, 2019Assignee: KLA-Tencor Corp.Inventors: Anatoly Romanovsky, Ivan Maleev, Daniel Kavaldjiev, Yury Yuditsky, Dirk Woll, Stephen Biellak, Mehdi Vaez-Iravani, Guoheng Zhao
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Publication number: 20190331592Abstract: A system for analyzing a sample includes an illumination source with a plurality of transmitting optical fibers optically coupled to the illumination source and a detector with a plurality of receiving optical fibers optically coupled to the detector. The system further includes a plurality of probes coupled to respective ones of the plurality of transmitting optical fibers and respective ones of the plurality of receiving optical fibers. The plurality of probes are configured to illuminate respective portions of a surface of the sample and configured to receive illumination reflected, refracted, or radiated from the respective portions of the surface of the sample. The system may further include one or more switches and/or splitters configured to optically couple respective ones of the plurality of transmitting optical fibers to the illumination source and/or configured to optically couple respective ones of the plurality of receiving optical fibers to the detector.Type: ApplicationFiled: June 26, 2018Publication date: October 31, 2019Inventors: Prasanna Dighe, Dieter Mueller, Dong Chen, Dengpeng Chen, Steve Zamek, Daniel Kavaldjiev, Alexander Buettner
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Publication number: 20180164228Abstract: Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered light that can be imaged on the entire area of the sensor, and wherein the sensor is configured to generate output responsive to the integrated pulses of scattered light; and a computer subsystem configured to detect defects on the wafer using the output generated by the sensor.Type: ApplicationFiled: January 29, 2018Publication date: June 14, 2018Inventors: Anatoly Romanovsky, Ivan Maleev, Daniel Kavaldjiev, Yury Yuditsky, Dirk Woll, Stephen Biellak, Mehdi Vaez-Iravani, Guoheng Zhao
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Patent number: 9915622Abstract: Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered light that can be imaged on the entire area of the sensor, and wherein the sensor is configured to generate output responsive to the integrated pulses of scattered light; and a computer subsystem configured to detect defects on the wafer using the output generated by the sensor.Type: GrantFiled: August 27, 2015Date of Patent: March 13, 2018Assignee: KLA-Tencor Corp.Inventors: Anatoly Romanovsky, Ivan Maleev, Daniel Kavaldjiev, Yury Yuditsky, Dirk Woll, Stephen Biellak, Mehdi Vaez-Iravani, Guoheng Zhao
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Patent number: 9891177Abstract: A wafer scanning system includes imaging collection optics to reduce the effective spot size. Smaller spot size decreases the number of photons scattered by the surface proportionally to the area of the spot. Air scatter is also reduced. TDI is used to produce a wafer image based on a plurality of image signals integrated over the direction of linear motion of the wafer. An illumination system floods the wafer with light, and the task of creating the spot is allocated to the imaging collection optics.Type: GrantFiled: October 3, 2014Date of Patent: February 13, 2018Assignee: KLA-Tencor CorporationInventors: Jijen Vazhaeparambil, Guoheng Zhao, Daniel Kavaldjiev, Anatoly Romanovsky, Ivan Maleev, Christian Wolters, Stephen Biellak, Bret Whiteside, Donald Pettibone, Yung-Ho Alex Chuang, David W. Shortt
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Publication number: 20160097727Abstract: A wafer scanning system includes imaging collection optics to reduce the effective spot size. Smaller spot size decreases the number of photons scattered by the surface proportionally to the area of the spot. Air scatter is also reduced. TDI is used to produce a wafer image based on a plurality of image signals integrated over the direction of linear motion of the wafer. An illumination system floods the wafer with light, and the task of creating the spot is allocated to the imaging collection optics.Type: ApplicationFiled: October 3, 2014Publication date: April 7, 2016Inventors: Jijen Vazhaeparambil, Guoheng Zhao, Daniel Kavaldjiev, Anatoly Romanovsky, Ivan Maleev, Christian Wolters, Stephen Biellak, Bret Whiteside, Donald Pettibone, Yung-Ho Alex Chuang, David W. Shortt
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Patent number: 9279774Abstract: Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to simultaneously form multiple illumination areas on the wafer with substantially no illumination flux between each of the areas. The system also includes a scanning subsystem configured to scan the multiple illumination areas across the wafer. In addition, the system includes a collection subsystem configured to simultaneously and separately image light scattered from each of the areas onto two or more sensors. Characteristics of the two or more sensors are selected such that the scattered light is not imaged into gaps between the two or more sensors. The two or more sensors generate output responsive to the scattered light. The system further includes a computer subsystem configured to detect defects on the wafer using the output of the two or more sensors.Type: GrantFiled: July 9, 2012Date of Patent: March 8, 2016Assignee: KLA-Tencor Corp.Inventors: Anatoly Romanovsky, Ivan Maleev, Daniel Kavaldjiev, Yury Yuditsky, Dirk Woll, Stephen Biellak, Mehdi Vaez-Iravani, Guoheng Zhao
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Publication number: 20150369753Abstract: Systems configured to inspect a wafer are provided. One system includes an illumination subsystem configured to direct pulses of light to an area on a wafer; a scanning subsystem configured to scan the pulses of light across the wafer; a collection subsystem configured to image pulses of light scattered from the area on the wafer to a sensor, wherein the sensor is configured to integrate a number of the pulses of scattered light that is fewer than a number of the pulses of scattered light that can be imaged on the entire area of the sensor, and wherein the sensor is configured to generate output responsive to the integrated pulses of scattered light; and a computer subsystem configured to detect defects on the wafer using the output generated by the sensor.Type: ApplicationFiled: August 27, 2015Publication date: December 24, 2015Inventors: Anatoly Romanovsky, Ivan Maleev, Daniel Kavaldjiev, Yury Yuditsky, Dirk Woll, Stephen Biellak, Mehdi Vaez-Iravani, Guoheng Zhao
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Patent number: 8934091Abstract: Methods, systems, and structures for monitoring incident beam position in a wafer inspection system are provided. One structure includes a feature formed in a chuck configured to support a wafer during inspection by the wafer inspection system. The chuck rotates the wafer in a theta direction and simultaneously translates the wafer in a radial direction during the inspection. An axis through the center of the feature is aligned with a radius of the chuck such that a position of the axis relative to an incident beam of the wafer inspection system indicates changes in the incident beam position in the theta direction.Type: GrantFiled: March 11, 2013Date of Patent: January 13, 2015Assignee: KLA-Tencor Corp.Inventors: Juergen Reich, Aleksey Petrenko, Richard Fong, Bret Whiteside, Jien Cao, Christian Wolters, Anatoly Romanovsky, Daniel Kavaldjiev
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Patent number: 8786842Abstract: A system for inspecting specimens such as semiconductor wafers is provided. The system provides scanning of dual-sided specimens using a diffraction grating that widens and passes nth order (n>0) wave fronts to the specimen surface and a reflective surface for each channel of the light beam. Two channels and two reflective surfaces are preferably employed, and the wavefronts are combined using a second diffraction grating and passed to a camera system having a desired aspect ratio. The system preferably comprises a damping arrangement which filters unwanted acoustic and seismic vibration, including an optics arrangement which scans a first portion of the specimen and a translation or rotation arrangement for translating or rotating the specimen to a position where the optics arrangement can scan the remaining portion(s) of the specimen. The system further includes-means for stitching scans together, providing for smaller and less expensive optical elements.Type: GrantFiled: February 5, 2007Date of Patent: July 22, 2014Assignee: KLA-Tencor CorporationInventors: Dieter Muller, Daniel Kavaldjiev, Rainer Schierle
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Patent number: 8629384Abstract: Disclosed herein is a PhotoMultiplier Tube (PMT) designed for use with a surface inspection system such as the Surfscan system, which operates at 266 nm wavelength. The inventive PMT is high efficiency, low noise, and low gain, a combination of features that is specific to the application and contrary to the features of PMT's in the art. The inventive PMT is designed to be tuned to a specific narrow band wavelength of incident light, thereby optimizing the QE at that wavelength. It is further designed to combine a small number of dynodes each having substantially higher secondary electron gain than typical dynodes. By designing the PMT in this way, the excess noise factor is dramatically reduced, yielding a much improved S/N, while still maintaining the overall PMT gain in the lower range suitable for use in a surface inspection system.Type: GrantFiled: October 22, 2010Date of Patent: January 14, 2014Assignee: KLA-Tencor CorporationInventors: Stephen Biellak, Daniel Kavaldjiev, Stuart Friedman