Patents by Inventor Xuedong Liu
Xuedong Liu 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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Publication number: 20110291007Abstract: The present invention generally relates to a detection unit of a charged particle imaging system. More particularly, portion of the detection unit can move into or out of the detection system as imaging condition required. With the assistance of a Wein filter (also known as an E×B charged particle analyzer) and a movable detector design, the present invention provides a stereo imaging system that suitable for both low current, high resolution mode and high current, high throughput mode. Merely by way of example, the invention has been applied to a scanning electron beam inspection system. But it would be recognized that the invention could apply to other system using charged particle beam as an observation tool.Type: ApplicationFiled: May 25, 2010Publication date: December 1, 2011Applicant: HERMES MICROVISION, INC.Inventors: YI-XIANG WANG, JOE WANG, XUEDONG LIU, ZHONGWEI CHEN
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Patent number: 8003953Abstract: The present invention relates to a multi-axis magnetic lens for a charged particle beam system. The apparatus eliminates the undesired non-axisymmetric transverse magnetic field components from the magnetic field generated by a common excitation coil and leaves the desired axisymmetric field for focusing each particle beam employed within the system.Type: GrantFiled: December 11, 2009Date of Patent: August 23, 2011Assignee: Hermes Microvision, Inc.Inventors: Zhongwei Chen, Weiming Ren, Kenichi Kanai, Xuedong Liu
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Publication number: 20110139996Abstract: The present invention relates to a multi-axis magnetic lens for a charged particle beam system. The apparatus eliminates the undesired non-axisymmetric transverse magnetic field components from the magnetic field generated by a common excitation coil and leaves the desired axisymmetric field for focusing each particle beam employed within the system.Type: ApplicationFiled: December 11, 2009Publication date: June 16, 2011Applicant: HERMES MICROVISION, INC.Inventors: ZHONGWEI CHEN, WEIMING REN, KENICHI KANAI, XUEDONG LIU
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Patent number: 7960697Abstract: The present invention relates to a charged particle beam apparatus which employs a scanning electron microscope for sample inspection and defect review. The present invent provides solution of improving imaging resolution by utilizing a field emission cathode tip with a large tip radius, applying a large accelerating voltage across ground potential between the cathode and anode, positioning the beam limit aperture before condenser lens, utilizing condenser lens excitation current to optimize image resolution, applying a high tube bias to shorten electron travel time, adopting and modifying SORIL objective lens to ameliorate aberration at large field of view and under electric drifting and reduce the urgency of water cooling objective lens while operating material analysis. The present invent provides solution of improving throughput by utilizing fast scanning ability of SORIL and providing a large voltage difference between sample and detectors.Type: GrantFiled: October 23, 2008Date of Patent: June 14, 2011Assignee: Hermes-Microvision, Inc.Inventors: Zhongwei Chen, Weiming Ren, Joe Wang, Xuedong Liu, Juying Dou, Fumin He, Feng Cao, Yan Ren, Xiaoli Guo, Wei He, Qingpo Xi
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Patent number: 7825386Abstract: System and method for charged particle beam. According an embodiment, the present invention provides a charged particle beam apparatus. The apparatus includes a charged particle source for generating a primary charged particle beam. The apparatus also includes at least one condenser lens for pre-focusing the primary charge particle beam. Furthermore, the apparatus includes a compound objective lens for forming the magnetic field and the electrostatic field to focus the primary charged particle beam onto a specimen in the charged particle beam path. The specimen includes a specimen surface. The compound objective lens includes a conical magnetic lens, an immersion magnetic lens, and an electrostatic lens, the conical magnetic lens including an upper pole piece, a shared pole piece being electrically insulated from the upper pole piece, and an excitation coil.Type: GrantFiled: October 24, 2007Date of Patent: November 2, 2010Assignee: Hermes-Microvision, Inc.Inventors: Xuedong Liu, Xu Zhang, Joe Wang, Edward Tseng, Zhongwei Chen
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Publication number: 20100270468Abstract: System and method for charged particle beam. According an embodiment, the present invention provides a charged particle beam apparatus. The apparatus includes a charged particle source for generating a primary charged particle beam. The apparatus also includes at least one condenser lens for pre-focusing the primary charge particle beam. Furthermore, the apparatus includes a compound objective lens for forming the magnetic field and the electrostatic field to focus the primary charged particle beam onto a specimen in the charged particle beam path. The specimen includes a specimen surface. The compound objective lens includes a conical magnetic lens, an immersion magnetic lens, and an electrostatic lens, the conical magnetic lens including an upper pole piece, a shared pole piece being electrically insulated from the upper pole piece, and an excitation coil.Type: ApplicationFiled: July 8, 2010Publication date: October 28, 2010Applicant: Hermes-Microvision, Inc.Inventors: Xuedong Liu, Xu Zhang, Joe Wang, Edward Tseng, Zhongwei Chen
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Patent number: 7759653Abstract: The present invention includes an electron beam device for examining defects on semiconductor devices. The device includes an electron source for generating a primary electron beam, wherein the total acceleration potential is divided and is provided across the ground potential. Also included is at least one condenser lens for pre-focusing the primary electron beam, an aperture for confining the primary electron beam to ameliorate electron-electron interaction, wherein the aperture is positioned right underneath the last condenser lens, and a SORIL objective lens system for forming immersion magnetic field and electrostatic field to focus the primary beam onto the specimen in the electron beam path. A pair of grounding rings for providing virtual ground voltage potential to those components within the electron beam apparatus installed below a source anode and above a last polepiece of the SORIL objective lens.Type: GrantFiled: May 30, 2008Date of Patent: July 20, 2010Assignee: Hermes Microvision, Inc.Inventors: Zhong-Wei Chen, Xuedong Liu, Xu Zhang, Weiming Ren, Juying Dou
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Publication number: 20100150429Abstract: The present invention relates to a defect review system, and/or particularly, to an apparatus and method of defect review sampling, review method and classification on a semiconductor wafer or a pattern lithography reticle during integrated circuit fabrication. These objects are achieved in comparing a reviewed image with a reference image pick-up through a smart sampling filter. A clustering computer system base on high speed network will provide data cache and save operation time and memory. A smart review sampling filter automatically relocate abnormal pattern or defects and classify the device location extracted from design database and/or from golden die image on the same substrate. The column of the present defect review system is comprised of the modified SORIL type objective lens. This column provides solution of improving throughput during sample review, material identification better image quality, and topography image of defect.Type: ApplicationFiled: December 15, 2008Publication date: June 17, 2010Applicant: HERMES-MICROVISION, INC.Inventors: Jack JAU, Zhongwei CHEN, Yi Xiang WANG, Chung-Shih PAN, Joe WANG, Xuedong LIU, Weiming REN, Wei FANG
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Publication number: 20100102227Abstract: The present invention relates to a charged particle beam apparatus which employs a scanning electron microscope for sample inspection and defect review. The present invent provides solution of improving imaging resolution by utilizing a field emission cathode tip with a large tip radius, applying a large accelerating voltage across ground potential between the cathode and anode, positioning the beam limit aperture before condenser lens, utilizing condenser lens excitation current to optimize image resolution, applying a high tube bias to shorten electron travel time, adopting and modifying SORIL objective lens to ameliorate aberration at large field of view and under electric drifting and reduce the urgency of water cooling objective lens while operating material analysis. The present invent provides solution of improving throughput by utilizing fast scanning ability of SORIL and providing a large voltage difference between sample and detectors.Type: ApplicationFiled: October 23, 2008Publication date: April 29, 2010Applicant: HERMES-MICROVISION, INCInventors: ZHONGWEI CHEN, WEIMING REN, JOE WANG, XUEDONG LIU, JUYING DOU, FUMIN HE, FENG CAO, YAN REN, XIAOLI GUO, WEI HE, QINGPO XI
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Electron beam apparatus to collect side-view and/or plane-view image with in-lens sectional detector
Patent number: 7705301Abstract: An electron beam apparatus and method are presented for collecting side-view and plane-view SEM imagery. The electron beam apparatus includes an electron source, some intermediate lenses if needed, an objective lens and an in-lens sectional detector. The electron source will provide an electron beam. The intermediate lenses focus the electron beam further. The objective lens is a combination of an immersion magnetic lens and a retarding electrostatic lens focuses the electron beam onto the specimen surface. The in-lens detector will be divided into two or more sections to collect secondary electrons emanating from the specimen with different azimuth and polar angle so that side-view SEM imagery can be obtained.Type: GrantFiled: May 30, 2007Date of Patent: April 27, 2010Assignee: Hermes Microvision, Inc.Inventors: Chi-Hua Tseng, Zhong-Wei Chen, Xuedong Liu -
Patent number: 7705298Abstract: This invention relates to apparatus and method to fast determine focus parameters in one pre-scan during an e-beam inspection practice. More specifically, embodiments of the present invention provide an apparatus and method that provide accurate focus tuning after primary focusing has been done.Type: GrantFiled: November 13, 2007Date of Patent: April 27, 2010Assignee: Hermes Microvision, Inc. (Taiwan)Inventors: Xuedong Liu, Zhonghua Dong, Wei Fang, Zhong-Wei Chen
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Publication number: 20090294664Abstract: The present invention includes an electron beam device for examining defects on semiconductor devices. The device includes an electron source for generating a primary electron beam, wherein the total acceleration potential is divided and is provided across the ground potential. Also included is at least one condenser lens for pre-focusing the primary electron beam, an aperture for confining the primary electron beam to ameliorate electron-electron interaction, wherein the aperture is positioned right underneath the last condenser lens, and a SORIL objective lens system for forming immersion magnetic field and electrostatic field to focus the primary beam onto the specimen in the electron beam path. A pair of grounding rings for providing virtual ground voltage potential to those components within the electron beam apparatus installed below a source anode and above a last polepiece of the SORIL objective lens.Type: ApplicationFiled: May 30, 2008Publication date: December 3, 2009Applicant: HERMES MICROVISION, INC.Inventors: Zhong-Wei Chen, Xuedong Liu, Xu Zhang, Weiming Ren, Juying Dou
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Publication number: 20090108199Abstract: This invention relates to apparatus and method to fast determine focus parameters in one pre-scan during an e-beam inspection practice. More specifically, embodiments of the present invention provide an apparatus and method that provide accurate focus tuning after primary focusing has been done.Type: ApplicationFiled: November 13, 2007Publication date: April 30, 2009Applicant: Hermes Microvision, Inc. (TAIWAN)Inventors: Xuedong LIU, Zhonghua DONG, Wei FANG, Zhong-Wei CHEN
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Publication number: 20080121810Abstract: System and method for charged particle beam. According an embodiment, the present invention provides a charged particle beam apparatus. The apparatus includes a charged particle source for generating a primary charged particle beam. The apparatus also includes at least one condenser lens for pre-focusing the primary charge particle beam. Furthermore, the apparatus includes a compound objective lens for forming the magnetic field and the electrostatic field to focus the primary charged particle beam onto a specimen in the charged particle beam path. The specimen includes a specimen surface. The compound objective lens includes a conical magnetic lens, an immersion magnetic lens, and an electrostatic lens, the conical magnetic lens including an upper pole piece, a shared pole piece being electrically insulated from the upper pole piece, and an excitation coil.Type: ApplicationFiled: October 24, 2007Publication date: May 29, 2008Applicant: Hermes-Microvision, Inc.Inventors: Xuedong Liu, Xu Zhang, Joe Wang, Edward Tseng, Zhongwei Chen
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ELECTRON BEAM APPARATUS TO COLLECT SIDE-VIEW AND/OR PLANE-VIEW IMAGE WITH IN-LENS SECTIONAL DETECTOR
Publication number: 20080006771Abstract: An electron beam apparatus and method are presented for collecting side-view and plane-view SEM imagery. The electron beam apparatus includes an electron source, some intermediate lenses if needed, an objective lens and an in-lens sectional detector. The electron source will provide an electron beam. The intermediate lenses focus the electron beam further. The objective lens is a combination of an immersion magnetic lens and a retarding electrostatic lens focuses the electron beam onto the specimen surface. The in-lens detector will be divided into two or more sections to collect secondary electrons emanating from the specimen with different azimuth and polar angle so that side-view SEM imagery can be obtained.Type: ApplicationFiled: May 30, 2007Publication date: January 10, 2008Applicant: Hermes Microvision, Inc. (TAIWAN)Inventors: Chi-Hua Tseng, Zhong-Wei Chen, Xuedong Liu -
Patent number: 5914267Abstract: A chimeric RNA molecule comprising at least one pre-mRNA processing element is disclosed. A gene construct comprising a DNA sequence encoding at least one pre-mRNA processing enhancer is also disclosed. A method of enhancing cytoplasmic RNA accumulation is disclosed. This method comprises the step of inserting a DNA sequence encoding the RNA into the vector described and expressing the DNA sequence.Type: GrantFiled: July 2, 1997Date of Patent: June 22, 1999Assignee: Wisconsin Alumni Research FoundationInventors: Janet E. Mertz, Xuedong Liu
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Patent number: 5686120Abstract: A chimeric RNA molecule comprising at least one pre-mRNA processing element is disclosed. A gene construct comprising a DNA sequence encoding at least one pre-mRNA processing enhancer is also disclosed. A method of enhancing cytoplasmic RNA accumulation is disclosed. This method comprises the step of inserting a DNA sequence encoding the RNA into the vector described and expressing the DNA sequence.Type: GrantFiled: May 22, 1995Date of Patent: November 11, 1997Assignee: Wisconsin Alumni Research FoundationInventors: Janet E. Mertz, Xuedong Liu