Photocathode Projection Patents (Class 250/492.24)
  • Patent number: 6573516
    Abstract: Disclosed are an electron-beam lithography method and system having precision in exposure improved by correcting a beam drift even within the same column of chips, and an electron-beam lithography system having the frequency of correcting a beam drift minimized without causing degradation of precision. In the electron-beam lithography method and electron-beam lithography system, a beam drift is measured frequently. When a beam drift is measured during exposure of each column of chips, a positional deviation is not corrected at the time but is corrected, step by step, while a plurality of stripes is defined. It is thus prevented that a misalignment between adjoining stripes gets larger. Moreover, a beam drift is measured a plurality of times in order to measure a variation in beam drift. If a beam drift is small, a measurement interval is extended. If a beam drift is large, the measurement interval is shortened.
    Type: Grant
    Filed: October 21, 1999
    Date of Patent: June 3, 2003
    Assignee: Advantest Corporation
    Inventor: Kenichi Kawakami
  • Patent number: 6566666
    Abstract: A method and an apparatus for pyroelectric lithography using a patterned emitter is provided. In the apparatus for pyroelectric lithography, a pyroelectric emitter or a ferroelectric emitter is patterned using a mask and it is then heated. Upon heating, electrons are not emitted from that part of the emitter covered by the mask, but are emitted from the exposed part of the emitter not covered by the mask so that the shape of the emitter pattern is projected onto the substrate. To prevent dispersion of emitted electron beams, which are desired to be parallel, the electron beams are controlled using a magnet or a projection system, thereby achieving exact a one-to-one projection or a x-to-one projection of the desired pattern etched on the substrate.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: May 20, 2003
    Assignees: Samsung Electronics Co., Ltd., Virginia Tech Intellectual Properties
    Inventor: In-Kyeong Yoo
  • Patent number: 6538256
    Abstract: A method and system for electron beam lithography at high throughput with shorter electron beam column length, reduced electron-electron interactions, and higher beam current. The system includes a photocathode having a pattern composed of a periodic array of apertures with a specific geometry. The spacing of the apertures is chosen so as to maximize the transmission of the laser beam through apertures significantly smaller than the photon wavelength. The patterned photocathode is illuminated by an array of laser beams to allow blanking and gray-beam modulation of the individual beams at the source level by the switching of the individual laser beams in the array. Potential applications for this invention include electron beam direct write on wafers and mask patterning.
    Type: Grant
    Filed: August 17, 2000
    Date of Patent: March 25, 2003
    Assignee: Applied Materials, Inc.
    Inventors: Marian Mankos, Vidhya Krishnamurthi, Kim Y. Lee
  • Publication number: 20030042434
    Abstract: An electron beam lithography system includes a laser for generating a laser beam, and a beam splitter for splitting the laser beam into a plurality of light beams. The intensity of the light beams is individually modulated. The light beams are of sufficient energy such that, when they impinge on a photocathode, electrons are emitted. Modulation of the light beams controls modulation of the resulting electron beams. The electron beams are provided to an electron column for focusing and scanning control. Finally, the electron beams are used to write a scanning surface, for example, using an interlaced writing strategy.
    Type: Application
    Filed: January 22, 2002
    Publication date: March 6, 2003
    Inventors: Marian Mankos, Steven T. Coyle, Andres Fernandez, Allan L. Sagle, Paul C. Allen, Xiaolan Chen, Douglas Holmgren, Windsor Owens, Jeffrey Sullivan, Tim Thomas, Mark A. Gesley
  • Patent number: 6528804
    Abstract: An ion implanter for low energy ion implantation includes an ion beam generator, a older for supporting a workpiece, such as a semiconductor wafer, and a voltage source electrically connected to the workpiece. The ion beam generator includes an ion source for generating ions and an extraction electrode having an extraction voltage applied thereto for accelerating the ions to form an ion beam. The voltage source applies to the workpiece a bias voltage that is of opposite polarity and smaller magnitude than the extraction voltage. The ions in the ion beam are implanted in the workpiece with an energy that is a function of the difference between the extraction voltage and the bias voltage.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: March 4, 2003
    Assignee: Varian Semiconductor Equipment Associate, Inc.
    Inventors: Philip Sullivan, George M. Gammel, Damian F. Brennan
  • Publication number: 20030030014
    Abstract: A lithography system comprising a converter element (7) for receiving light and converting said light in a plurality of electron beams (15) to be directed towards and focused on a substrate (10) to be processed, said plurality of electron beams (15) being used to define a pattern in a resist layer (20) on said substrate (10), wherein said lithography system is provided with a protective foil with holes at the positions of the electron beams (23) being arranged to protect, in use, said converter element (7) from contamination with material from the resist layer (21).
    Type: Application
    Filed: August 13, 2002
    Publication date: February 13, 2003
    Inventors: Marco Wieland, Bert Jan Kampherbeek, Pieter Kruit
  • Patent number: 6515292
    Abstract: A photocathode electron projector is formed with a sample attached to an anode and a patterned quartz mask attached to a cathode. The quartz mask is patterned with Au—Pd layers that emit electrons when illuminated by ultraviolet light. The ultraviolet light is filtered to just above the work function of the Au—Pd material. This has the effect of causing substantially monochromatic electrons to be emitted. The electrons are brought under influence of a parallel electric and magnetic field to thereby undergo a cyclotronic orbit. An integer number of cyclotronic orbits insures that the electrons hit the sample substantially at the same location as they were on mask.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: February 4, 2003
    Assignee: California Institute of Technology
    Inventors: Axel Scherer, Elena Vuckovic
  • Publication number: 20030006381
    Abstract: A method and an apparatus for pyroelectric lithography using a patterned emitter is provided. In the apparatus for pyroelectric lithography, a pyroelectric emitter or a ferroelectric emitter is patterned using a mask and it is then heated. Upon heating, electrons are not emitted from that part of the emitter covered by the mask, but are emitted from the exposed part of the emitter not covered by the mask so that the shape of the emitter pattern is projected onto the substrate. To prevent dispersion of emitted electron beams, which are desired to be parallel, the electron beams are controlled using a magnet or a projection system, thereby achieving exact a one-to-one projection or a x-to-one projection of the desired pattern etched on the substrate.
    Type: Application
    Filed: August 29, 2002
    Publication date: January 9, 2003
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: In-Kyeong Yoo
  • Patent number: 6476401
    Abstract: A moving photoconverter device that converts an incident light image into an equivalent electron or other charged particle beam image. The moving photoconverter is ring shaped and is rotated by using a motor such that the incident light image exposes a moving photoconverter surface. The photoconverter may additionally or alternatively move in an X-Y motion or radially. Continuous regeneration is provided at a site remote from the region of moving photoconverter device that converts an incident light image into an equivalent electron or other charged particle beam image.
    Type: Grant
    Filed: September 16, 1999
    Date of Patent: November 5, 2002
    Assignee: Applied Materials, Inc.
    Inventors: Lee H. Veneklasen, Marian Mankos, Bart Scholte van Mast
  • Patent number: 6476402
    Abstract: A method and an apparatus for pyroelectric lithography using a patterned emitter is provided. In the apparatus for pyroelectric lithography, a pyroelectric emitter or a ferroelectric emitter is patterned using a mask and it is then heated. Upon heating, electrons are not emitted from that part of the emitter covered by the mask, but are emitted from the exposed part of the emitter not covered by the mask so that the shape of the emitter pattern is projected onto the substrate. To prevent dispersion of emitted electron beams, which are desired to be parallel, the electron beams are controlled using a magnet or a projection system, thereby achieving exact a one-to-one projection or a x-to-one projection of the desired pattern etched on the substrate.
    Type: Grant
    Filed: July 19, 2000
    Date of Patent: November 5, 2002
    Assignees: Samsung Electronics Co., Ltd., Virginia Tech Intellectual Properties, Inc.
    Inventor: In-Kyeong Yoo
  • Patent number: 6448568
    Abstract: A lithography apparatus including both a laser beam source and an electron beam column, where the electron beam column has a support(in one embodiment a window in the column housing) having an index of refraction n. The support, having a photocathode source material disposed on its remote surface, is located in some embodiments such that the internal angle of the incident laser beam is &thgr; with respect to a line perpendicular to the remote surface. The numerical aperture of the substrate(equal to nsin &thgr;) is greater than one in one embodiment, resulting in a high resolution spot size diameter incident on the photocathode source material at the remote surface. Incident energy from the laser beam thereby emits a corresponding high resolution electron beam from the photocathode source material. Electromagnetic lens components are disposed downstream in the electron beam column to demagnify the electron beam.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: September 10, 2002
    Assignee: Applied Materials, Inc.
    Inventors: Paul C. Allen, Xiaolan Chen, Douglas E. Holmgren, Samuel C. Howells
  • Patent number: 6448722
    Abstract: A compact high energy photoelectron injector integrates the photocathode directly into a multicell linear accelerator with no drift space between the injection and the linac. High electron beam brightness is achieved by accelerating a tightly focused electron beam in an integrated, multi-cell, X-band rf linear accelerator (linac). The photoelectron linac employs a Plane-Wave-Transformer (PWT) design which provides strong cell-to-cell coupling, easing manufacturing tolerances and costs.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: September 10, 2002
    Assignee: Duly Research Inc.
    Inventors: David U. L. Yu, James Rosenzweig
  • Patent number: 6429443
    Abstract: Multiple beam electron beam lithography uses an array of vertical cavity surface emitting lasers (VCSELS) to generate laser beams, which are then converted to electron beams using a photocathode. The electron beams are scanned across a semiconductor substrate or lithography mask to imprint a pattern thereon. The use of VCSELs simplifies the design of the electron beam column and improves the throughput and writing resolution of the lithography system.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: August 6, 2002
    Assignee: Applied Materials, Inc.
    Inventors: Marian Mankos, Steven T Coyle, Andres Fernandez, Tai-Hon P Chang
  • Patent number: 6373072
    Abstract: A lithographic projection apparatus has a radiation system for supplying a projection beam of radiation, a mask table provided with a mask holder for holding a mask, a substrate table provided with a substrate holder for holding a substrate, a projection system for imaging an irradiated portion of the mask onto a target portion of the substrate, first driving means, for moving the mask table in a given reference direction substantially parallel to the plane of the table, second driving means, for moving the substrate table parallel to the reference direction so as to be synchronous with the motion of the mask table.
    Type: Grant
    Filed: June 21, 1999
    Date of Patent: April 16, 2002
    Assignee: ASM Lithography B.V.
    Inventors: Hans Butler, Thomas Petrus Hendricus Warmerdam
  • Patent number: 6215128
    Abstract: An improved compact tandem photon and electron beam lithography system includes a field lens adjacent the photoemission source which is utilized in combination with an objective lens to minimize field aberrations in the usable emission pattern and minimize the interaction between electrons to improve the throughput of the system. If desired, a demagnifying lens can be utilized between the field lens and the objective lens to increase the demagnification ratio of the system.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: April 10, 2001
    Assignee: Etec Systems, Inc.
    Inventors: Marian Mankos, Lee H. Veneklasen