Patents by Inventor Mehran Nasser-Ghodsi

Mehran Nasser-Ghodsi 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: 8698094
    Abstract: A permanent magnetic lens array for charged-particle focusing includes a first sheet of soft magnetic material, wherein the first sheet of soft magnetic material includes a plurality of snorkel cone protrusions arranged in an array pattern, wherein each snorkel cone is axially symmetric and includes an opening passing from a first surface of the first sheet of soft magnetic material to a second surface of soft magnetic material, and a plurality of permanent magnetic elements, wherein each permanent magnetic element is axially symmetric and arranged concentrically with a snorkel cone of the first sheet of soft magnetic material, wherein the snorkel cones of the first sheet of soft magnetic material and the plurality of permanent magnetic elements are configured to form a plurality of magnetic lenses, wherein each magnetic lens has a magnetic field with an axial component oriented perpendicular to the first surface of the soft magnetic material.
    Type: Grant
    Filed: July 20, 2011
    Date of Patent: April 15, 2014
    Assignee: KLA-Tencor Corporation
    Inventors: Christopher Sears, Mehran Nasser-Ghodsi, Khashayar Shadman
  • Patent number: 8658973
    Abstract: System and methods for decomposing an Auger electron spectrum into elemental and chemical components, includes conditioning and input spectrum to generate a normalized input spectrum; determining statistical correlation between the normalized input spectrum and stored elemental spectral signatures; and characterizing elemental or chemical species in the input spectrum from the statistical correlation, wherein said conditioning the input spectrum includes estimating a background signal of non-Auger electrons in the input spectrum and subtracting the estimated background signal from the input spectrum.
    Type: Grant
    Filed: June 7, 2013
    Date of Patent: February 25, 2014
    Assignee: KLA-Tencor Corporation
    Inventors: Mark Neil, Mehran Nasser-Ghodsi, Christopher Sears
  • Patent number: 8633457
    Abstract: A background reduction system may include, but is not limited to: a charged particle source configured to generate a charged-particle beam; a louvered structure including one or more apertures configured to selectively transmit charged particles according to their angle of incidence; and a charged-particle detector configured to receive charged particles selectively transmitted by the louvered structure.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: January 21, 2014
    Assignee: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Christopher Sears, Robert Haynes
  • Patent number: 8618513
    Abstract: One embodiment disclosed relates to an apparatus forming an electrical conduction path through an insulating layer on a surface of a substrate. A first radiation source is configured to emit radiation to a first region of the insulating layer, and a first electrical contact is configured to apply a first bias voltage to the first region. A second radiation source is configured to emit radiation to a second region of the insulating layer, and a second electrical contact is configured to apply a second bias voltage to the second region. The conductivities of the regions are increased by the radiation such that conductive paths are formed through the insulating layer at those regions. In one implementation, the apparatus may be used in an electron beam instrument. Another embodiment relates to a method of forming an electrical conduction path through an insulating layer. Other embodiments, aspects and features are also disclosed.
    Type: Grant
    Filed: May 10, 2012
    Date of Patent: December 31, 2013
    Assignee: KLA-Tencor Corporation
    Inventors: Tomas Plettner, Mehran Nasser-Ghodsi, Robert G. Haynes, Rudy F. Garcia
  • Publication number: 20130341504
    Abstract: System and methods for decomposing an Auger electron spectrum into elemental and chemical components, includes conditioning and input spectrum to generate a normalized input spectrum; determining statistical correlation between the normalized input spectrum and stored elemental spectral signatures; and characterizing elemental or chemical species in the input spectrum from the statistical correlation, wherein said conditioning the input spectrum includes estimating a background signal of non-Auger electrons in the input spectrum and subtracting the estimated background signal from the input spectrum.
    Type: Application
    Filed: June 7, 2013
    Publication date: December 26, 2013
    Applicant: KLA -Tencor Corporation,
    Inventors: Mark Neill, Mehran Nasser-Ghodsi, Christopher Sears
  • 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
  • Patent number: 8530867
    Abstract: Contamination may be removed from a field emitter unit during operation of the emitter unit in an environment at a pressure that lies within a range between 10?6 torr and 10?8 torr. At regular predetermined intervals an electron beam from an emitter tip may be deflected away from a path through a beam defining aperture and onto an electron collector. An electron beam current to the electron collector may be determined and the emitter unit may be flash heated if the current to the electron collector is below a threshold. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: September 10, 2013
    Assignee: KLA-Tencor Corporation
    Inventor: Mehran Nasser-Ghodsi
  • Patent number: 8513619
    Abstract: One embodiment disclosed relates to an electron source for generating an electron beam. The electron source includes an electron emitter having a tip from which an electron beam is extracted. The electron further includes a non-planar extractor with an extractor opening and a built-in beam-limiting aperture. The extractor opening is larger than the beam-limiting aperture, and central axes of both the extractor opening and the beam-limiting aperture are aligned with the tip along a beam axis. Another embodiment relates to a method of generating an electron beam using an electron source having a non-planar extractor. Another embodiment relates to an array of electron sources for generating an array of electron beams. The array of electron sources includes an array of electron emitters and an array of non-planar extractor structures. Other embodiments, aspects and features are also disclosed.
    Type: Grant
    Filed: May 10, 2012
    Date of Patent: August 20, 2013
    Assignee: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Tomas Plettner, Robert G. Haynes, Christopher Malcolm Stanley Sears
  • Patent number: 8455838
    Abstract: One embodiment disclosed relates an apparatus which includes an electromagnet arranged to provide a large-scale magnetic field in a region. The apparatus further includes an array of multiple electron beam columns formed in the region using an array of bores through magnetic material. Another embodiment relates to a method of generating an array of electron beams. A large-scale magnetic field is generated in a region using at least two magnetic poles. The array of electron beams is generated using an array of columns formed using bores through a magnetic material positioned in the region. Other embodiments, aspects and features are also disclosed.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: June 4, 2013
    Assignee: KLA-Tencor Corporation
    Inventors: Khashayar Shadman, Robert G. Haynes, Christopher Malcolm Stanley Sears, Mehran Nasser-Ghodsi
  • Patent number: 8421030
    Abstract: One embodiment relates to a charged-particle energy analyzer apparatus. A first mesh is arranged to receive the charged particles on a first side and pass the charged particles to a second side, and a first electrode is arranged such that a first cavity is formed between the second side of the first mesh and the first electrode. A second mesh is arranged to receive the charged particles on a second side and pass the charged particles to a first side, and a second electrode is arranged such that a second cavity is formed between the first side of the second mesh and the second electrode. Finally, a third mesh is arranged to receive the charged particles on a first side and pass the charged particles to a second side, and a position-sensitive charged-particle detector is arranged to receive the charged particles after the charged particles pass through the third mesh.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: April 16, 2013
    Assignee: KLA-Tencor Corporation
    Inventors: Khashayar Shadman, Robert Haynes, Gabor D. Toth, Christopher Sears, Mehran Nasser Ghodsi
  • Publication number: 20130001417
    Abstract: A background reduction system may include, but is not limited to: a charged particle source configured to generate a charged-particle beam; a louvered structure including one or more apertures configured to selectively transmit charged particles according to their angle of incidence; and a charged-particle detector configured to receive charged particles selectively transmitted by the louvered structure.
    Type: Application
    Filed: June 30, 2011
    Publication date: January 3, 2013
    Applicant: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Christopher Sears, Robert Haynes
  • Publication number: 20130001418
    Abstract: One embodiment disclosed relates an apparatus which includes an electromagnet arranged to provide a large-scale magnetic field in a region. The apparatus further includes an array of multiple electron beam columns formed in the region using an array of bores through magnetic material. Another embodiment relates to a method of generating an array of electron beams. A large-scale magnetic field is generated in a region using at least two magnetic poles. The array of electron beams is generated using an array of columns formed using bores through a magnetic material positioned in the region. Other embodiments, aspects and features are also disclosed.
    Type: Application
    Filed: June 25, 2012
    Publication date: January 3, 2013
    Inventors: Khashayar SHADMAN, Robert G. HAYES, Christopher Malcolm Stanley SEARS, Mehran NASSER-GHODSI
  • Publication number: 20120298879
    Abstract: One embodiment disclosed relates to an apparatus forming an electrical conduction path through an insulating layer on a surface of a substrate. A first radiation source is configured to emit radiation to a first region of the insulating layer, and a first electrical contact is configured to apply a first bias voltage to the first region. A second radiation source is configured to emit radiation to a second region of the insulating layer, and a second electrical contact is configured to apply a second bias voltage to the second region. The conductivities of the regions are increased by the radiation such that conductive paths are formed through the insulating layer at those regions. In one implementation, the apparatus may be used in an electron beam instrument. Another embodiment relates to a method of forming an electrical conduction path through an insulating layer. Other embodiments, aspects and features are also disclosed.
    Type: Application
    Filed: May 10, 2012
    Publication date: November 29, 2012
    Inventors: Tomas PLETTNER, Mehran NASSER-GHODSI, Robert HAYNES, Rudy F. GARCIA
  • Patent number: 8283631
    Abstract: A spectrometer having an electron beam generator for generating an electron beam that is directed at a sample. An electron beam positioner directs the electron beam onto a position of the sample, and thereby produces a secondary emitted stream from the sample, where the secondary emitted stream includes at least one of electrons and x-rays. An secondary emitted stream positioner positions the secondary emitted stream onto a detector array, which receives the secondary emitted stream and detects both the amounts and the received positions of the secondary emitted stream. A modulator modulates the electron beam that is directed onto the sample, and thereby sweeps the electron beam between a first position and a second position on the sample. An extractor is in signal communication with both the modulator and the detector array, and extracts a differential signal that represents a difference between the signals that are received from the first position and the signals that are received from the second position.
    Type: Grant
    Filed: January 9, 2009
    Date of Patent: October 9, 2012
    Assignee: KLA-Tencor Corporation
    Inventors: Mehdi Vaez-Iravani, Mehran Nasser-Ghodsi, Guoheng Zhao
  • Patent number: 8237120
    Abstract: A defect may be characterized using primary radiation directed from a primary electron source to a measurement location on the sample. An electron energy analyzer may capture secondary electrons emitted from the measurement location in a focusing direction by an electron energy analyzer. A transverse focusing device may focus electrons emitted from the measurement location in a transverse direction that is perpendicular to the focusing direction.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: August 7, 2012
    Assignee: KLA-Tencor Corporation
    Inventors: Gabor Toth, Rudy Garcia, Mehran Nasser-Ghodsi, Khashayar Shadman, Ming Lun Yu, Stuart Friedman
  • Patent number: 8202440
    Abstract: Disclosed are methods and apparatus for etching a sample, such as a semiconductor device or wafer. In general terms, embodiments of the present invention allow dry etching of a material on a sample, such as a copper material, at room temperature using a reactive substance, such as a chorine based gas. For example, the mechanisms of the present invention allow precise etching of a copper material to produce fine feature patterns without heating up the whole device or substrate to an elevated temperature such as 50° C. and above. The etching is assisted by simultaneously scanning a charged particle beam, such as an electron beam, and a photon beam, such as a laser beam, over a same target area of the sample while the reactive substance is introduced near the same target area. The reactive substance, charged particle beam, and photon beam act in combination to etch the sample at the target area. For example, a copper layer may be etched using the mechanisms of the present invention.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: June 19, 2012
    Assignee: KLA-Tencor Corporation
    Inventors: Mehran Nasser-Ghodsi, Ying Wang, Harrison Chin, Anne Testoni, R. Chris Burns
  • Patent number: 8188451
    Abstract: Contamination may be removed from an emitter tip of a field emitter during operation of the emitter tip in a system having an electron beam column having an electrode with a beam defining aperture, an electron collector located proximate to the beam defining aperture between the electrode and the field emitter, and an electron deflector located between the emitter tip and the electron collector. At regular predetermined intervals an electron beam from the emitter tip may be deflected away from a path through the beam defining aperture and onto the electron collector. An electron beam current to the electron collector may be determined and the emitter tip may be flash heated if the current to the electron collector is below a threshold.
    Type: Grant
    Filed: September 17, 2009
    Date of Patent: May 29, 2012
    Assignee: KLA-Tencor Corporation
    Inventor: Mehran Nasser-Ghodsi
  • Patent number: 8008207
    Abstract: A method for controlling chemical dry etching to improve smoothness of an etched surface is disclosed. Ions are implanted into a surface to form a volatilizable compound at a temperature low enough to avoid, reduce, or eliminate formation of three-dimensional structures of the volatilizable compound that might create the roughness at an etched surface of the volatilizable compound. The ions are applied in a sufficient energy to penetrate to a predetermined depth of material that is to be removed from the surface in an etching cycle, and in a sufficient dosage to achieve full formation of the volatilizable compound. The surface of the volatilizable compound is exposed to a gas composition for a time duration sufficient to completely etch the volatilizable compound.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: August 30, 2011
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Ming Lun Yu, Mehran Nasser-Ghodsi
  • Publication number: 20110168886
    Abstract: One embodiment relates to a charged-particle energy analyzer apparatus. A first mesh is arranged to receive the charged particles on a first side and pass the charged particles to a second side, and a first electrode is arranged such that a first cavity is formed between the second side of the first mesh and the first electrode. A second mesh is arranged to receive the charged particles on a second side and pass the charged particles to a first side, and a second electrode is arranged such that a second cavity is formed between the first side of the second mesh and the second electrode. Finally, a third mesh is arranged to receive the charged particles on a first side and pass the charged particles to a second side, and a position-sensitive charged-particle detector is arranged to receive the charged particles after the charged particles pass through the third mesh.
    Type: Application
    Filed: July 16, 2010
    Publication date: July 14, 2011
    Inventors: Khashayar Shadman, Robert Haynes, Gabor D. Toth, Christopher Sears, Mehran Nasser Ghodsi
  • Patent number: 7945086
    Abstract: A first embodiment of the invention relates to a method for evaluating the quality of structures on an integrated circuit wafer. Test structures formed on either on the integrated or on a test wafer are exposed to an electron beam and an electron-beam activated chemical etch. The electron-beam activated etching gas or vapor etches the test structures, which are analyzed after etching to determine a measure of quality of the test structures. The measure of quality may be used in a statistical process control to adjust the parameters used to form device structures on the integrated circuit wafer. The test structures are formed on an integrated circuit wafer having two or more die. Each die has one or more integrated circuit structures. The test structures are formed on scribe lines between two or more adjacent die. Each test structure may correspond in dimensions and/or composition to one or more of the integrated circuit structures.
    Type: Grant
    Filed: January 12, 2007
    Date of Patent: May 17, 2011
    Assignee: KLA-Tencor Technologies Corporation
    Inventors: Yehiel Gotkis, Sergey Lopatin, Mehran Nasser-Ghodsi