Plasma Containment Patents (Class 315/111.71)
  • Publication number: 20020149317
    Abstract: The performance of a plasma processing apparatus which is disassembled, transferred, and reassembled is evaluated. The plasma processing apparatus has a plasma processing chamber having an electrode for exciting a plasma, a radiofrequency generator connected to the electrode, and an impedance matching circuit for performing the impedance matching between the plasma processing chamber and the radiofrequency generator. The performance of the apparatus is evaluated whether or not three times the first series resonant frequency of the plasma processing chamber is larger than the power frequency supplied to the plasma processing chamber.
    Type: Application
    Filed: September 20, 2001
    Publication date: October 17, 2002
    Inventors: Akira Nakano, Tadahiro Ohmi
  • Patent number: 6465964
    Abstract: A plasma treatment apparatus can generate atmospheric pressure plasma with reliability by help of an ignition electrode to facilitate starting the apparatus without using an expensive impedance matching device. The apparatus comprises a plasma-generation chamber having an aperture from which the plasma blows out, a gas supply unit for supplying a gas for plasma generation into the chamber, a pair of electrodes, a power source for applying an AC electric field between the electrodes to maintain the plasma in the chamber, a pulse generator for providing a pulse voltage, and the ignition electrode for applying the pulse voltage to the gas supplied in the chamber to generate the plasma.
    Type: Grant
    Filed: October 24, 2000
    Date of Patent: October 15, 2002
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Noriyuki Taguchi, Yasushi Sawada, Keiichi Yamazaki, Yoshiyuki Nakazono, Yukiko Inooka, Kazuya Kitayama
  • Patent number: 6456010
    Abstract: A discharge plasma generating method includes (a) opposing a discharge electrode having a substantially plane discharge portion to a substrate to be processed in a vacuum reaction vessel such that the discharge electrode and the substrate are substantially parallel to each other, (b) evacuating the vacuum reaction vessel and supplying a process gas to a space between the discharge electrode and the substrate, and (c) applying HF power to the discharge electrode such that an envelope representing the spatial distribution of a HF voltage &phgr; on the discharge electrode in a split second changes in accordance with a function including time as a parameter, thereby generating a discharge plasma of the process gas between the discharge electrode and the substrate, with substantially no standing wave of the HF voltage &phgr; generated on the discharge electrode.
    Type: Grant
    Filed: January 10, 2001
    Date of Patent: September 24, 2002
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hideo Yamakoshi, Koji Satake, Yoshiaki Takeuchi, Hiroshi Mashima, Tatsufumi Aoi, Masayoshi Murata
  • Patent number: 6452315
    Abstract: An improved apparatus is provided for in-situ cleaning of electron microscopes and other vacuum chambers. A special RF plasma electrode is housed in a compact cylinder constructed of standard vacuum components and a electrical feedthrough. The device allows oxygen radicals to be generated from air by a low powered RF plasma. The oxygen radical flow by convection into the electron microscope or vacuum chamber to be cleaned and react with hydrocarbons to form CO and H2O vapor which is pumped away.
    Type: Grant
    Filed: February 8, 2000
    Date of Patent: September 17, 2002
    Inventor: Ronald A. Vane
  • Patent number: 6445134
    Abstract: A plasma pinch having an inner/outer coaxial tube arrangement, which nested tube arrangement yields a higher-performance pinchlamp than is capable with a single-tube configuration. Further, each tube contains a separate gas, the inner tube filled with Argon, and the outer tube filled with Helium. The inner/outer coaxial tube arrangement of the present invention facilitates the use of an inner tube to contain a volume of Argon gas as the working gas. The outer tube is coaxial with the inner tube, surrounding the inner tube with contained Helium gas. The configuration of an outer tube filled with Helium presents external pressures to the inner tube. The contained Helium gas in the outer tube, among other things, compresses and supports the walls of the inner tube, enabling the inner tube to be smaller in diameter than prior art plasma chambers, which chambers would shatter if made with as small a diameter as the present inner tube.
    Type: Grant
    Filed: November 30, 2000
    Date of Patent: September 3, 2002
    Assignee: Environmental Surface Technologies
    Inventor: John F. Asmus
  • Patent number: 6441552
    Abstract: A persistent ionization plasma generator is described that forms a plasma in a cavity that persists for a time after termination of the exciting RF electric field. The plasma generator includes a RF cavity that is in fluid communication with a source of ionizing gas. The RF cavity can be at substantially atmospheric pressure. An RF power source that generates an RF electric field is electromagetically coupled to the RF cavity. An ultraviolet light source is positioned in optical communication to the cavity. An antenna is positioned within the cavity adjacent to the ultraviolet light source. A chamber for confining the plasma can be positioned in the cavity around the antenna.
    Type: Grant
    Filed: April 29, 1999
    Date of Patent: August 27, 2002
    Assignee: Physical Sciences Inc.
    Inventors: John E. Brandenburg, John F. Kline, Joshua H. Resnick
  • Patent number: 6436230
    Abstract: A process device and a method for processing a substrate. A dipole ring magnet (DRM) is arranged in a manner so that a leakage magnetic field in the neighborhood of the process device and at a position a prescribed distance therefrom is minimized. The dipole ring magnet (DRM) rotates around an outer periphery of a process chamber which has a plasma generation device, a substantially cylindrical shield plate covering an outer periphery of the dipole ring magnet. The shield is rotated coaxially with the dipole ring magnet and in a direction opposite to the rotation of the dipole ring magnet. In this way a magnetic field is generated in a direction that cancels leakage magnetic flux generated outside the dipole ring magnet.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: August 20, 2002
    Assignee: Tokyo Electron Limited
    Inventors: Tomomi Kondo, Hidetoshi Kimura
  • Patent number: 6433484
    Abstract: A plasma processing chamber is provided which provides improved wafer area pressure control. The plasma processing chamber is a vacuum chamber with a device connected for generating and sustaining a plasma. Part of this device would be an etchant gas source and an exhaust port. A confinement ring defines an area above a wafer. The wafer area pressure is dependent on the pressure drop across the confinement ring. The confinement ring is part of a confinement device that provides wafer area pressure control greater than 40%. Such a confinement device may be a fixed vertical restriction ring in addition to the confinement ring, where the confinement ring is adjustable. In the alternative, three adjustable confinement rings may be used to provide the desired wafer area pressure control.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: August 13, 2002
    Assignee: Lam Research Corporation
    Inventors: Fangli Hao, Eric Lenz, Bruno Morel
  • Patent number: 6422825
    Abstract: A plasma pumping cell and method for pumping ions from a first region containing a plasma to a second region when the plasma pumping cell is interposed between the first and second regions, the plasma pumping cell including: a partition member (4) positioned between the first and second regions, the partition member (4) having a through opening defining a conduit (22); a plurality of magnets (24) positioned relative to the conduit in a manner to provide lines of magnetic force that extend through the conduit; a source of free electrons in communication with the conduit; and an electric potential source (34) disposed relative to the conduit to create an electrostatic field which accelerates ions from the conduit (22) to the second region.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: July 23, 2002
    Assignee: Tokyo Electron Limited
    Inventors: Raphael A. Dandl, Wayne L. Johnson, Gareth Guest
  • Patent number: 6418874
    Abstract: A toroidal plasma source (28) within a substrate processing chamber (10). The toroidal plasma source forms a poloidal plasma with theta symmetry. The poloidal plasma current is essentially parallel to a surface of the plasma generating structure, thus reducing sputtering erosion of the inner walls. The plasma current is similarly essentially parallel to a process surface (32) of a substrate (34) within the chamber. In a further embodiment, a shaped member (66) between the substrate and the plasma source controls the plasma density in a selected fashion to enhance plasma processing uniformity.
    Type: Grant
    Filed: May 25, 2000
    Date of Patent: July 16, 2002
    Assignee: Applied Materials, Inc.
    Inventors: Michael S. Cox, Canfeng Lai, Robert B. Majewski, David P. Wanamaker, Christopher T. Lane, Peter Loewenhardt, Shamouil Shamouilian, John P. Parks
  • Patent number: 6417625
    Abstract: An apparatus for producing a stable, high pressure plasma column with long length, and high axial uniformity. Rotating a gas-filled tube about an horizontal axis creates a vortex with minimal, or no shear flow. Such a vortex provides a stable equilibrium for a central column of high temperature gas and plasma when, for a given rotation speed, the centrifugal force dominates over the gravitational force inside the smallest radial dimension of the containment envelope. High pressure discharges inside a rotating envelope may be sustained by a variety of energy sources, including electrical, electromagnetic and chemical; they may find application in plasma torches, light sources, etc.
    Type: Grant
    Filed: August 4, 2000
    Date of Patent: July 9, 2002
    Assignee: General Atomics
    Inventors: Neil H. Brooks, Torkil H. Jensen, Charles P. Moeller
  • Patent number: 6404134
    Abstract: A plasma processing system includes a processing vessel for housing therein an object to be processed. In the upper portion of the processing vessel, a substantially disk-shaped electrode plate having a facing surface facing the object is provided. A radio-frequency wave supply unit supplies radio-frequency waves having a flattened waveform which forms substantially a sinusoidal wave whose crest and trough portions are substantially horizontally flattened. The radio-frequency waves supplied from the supply unit are propagated in diametrically opposite directions on the facing surface of the electrode to form standing waves. Similar to the supplied radio-frequency waves, the standing waves also have a waveform which forms substantially a sinusoidal wave whose crest and trough portions are substantially horizontally flattened.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: June 11, 2002
    Assignee: Tokyo Electron Limited
    Inventor: Nobuo Ishii
  • Publication number: 20020063530
    Abstract: A discharge tube (11) made of a dielectric material extends through a hole (3) of a rectangular waveguide (1) and through a coaxial microwave cavity (4) so as to be coaxial with the central axis of the cavity (4). This discharge tube (11) has a double-tube structure including an outer tube (12) and an inner tube (13). The sectional area of an annular gap formed between the outer tube (12) and the inner tube (13) is held constant over the entire length of the inner tube (13). This allows the generation of a stable thermal plasma when a reaction gas containing an organic halide and water vapor is supplied into the outer tube through the annular gap with a microwave transmitted from the rectangular waveguide (1) into the cavity (4).
    Type: Application
    Filed: December 12, 2001
    Publication date: May 30, 2002
    Applicant: Mitsubishi Heavy Industries, Inc.
    Inventors: Tetsuya Ikeda, Minoru Danno
  • Patent number: 6396214
    Abstract: A device for generating a free cold plasma beam having a high-frequency plasma source and a hollow body transparent to electromagnetic radiation, which is provided with at least one gas inlet opening and at least one beam outlet opening is proposed. The high-frequency plasma source is in particular a microwave plasma source or a high-frequency plasma source and initially generates at least within the hollow body a cold gas plasma, which is conducted as a free cold plasma beam via the beam outlet opening from the hollow body and enters the work chamber. The work chamber is under vacuum. The free plasma beam remains bundled in the work chamber and can be used there for cleaning, etching, or plasma coating with a reactive gas.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: May 28, 2002
    Assignee: Robert Bosch GmbH
    Inventors: Stefan Grosse, Thomas Weber, Astrid Gahl
  • Patent number: 6380685
    Abstract: The design and manufacturing processes for Hollow Cathode Assemblies (HCA's) that operate over a broad range of emission currents up to 30 Amperes, at low potentials, with lifetimes in excess of 17,500 hours. The processes include contamination control procedures which cover hollow cathode component cleaning procedures, gas feed system designs and specifications, and hollow cathode activation and operating procedures to thereby produce cathode assemblies that have demonstrated stable and repeatable operating conditions, for both the discharge current and voltage. The HCA of this invention provides lifetimes of greater than 10,000 hours, and expected lifetimes of greater than 17,500 hours, whereas the present state-of-the-art is less than 500 hours at emission currents in excess of 1 Ampere.
    Type: Grant
    Filed: December 28, 2000
    Date of Patent: April 30, 2002
    Assignee: United States of America as represented by the Administrator of National Aeronautics and Space Administration
    Inventors: Michael J. Patterson, Timothy R. Verhey, George C. Soulas
  • Publication number: 20020047543
    Abstract: A plasma density information measuring method capable of easily measuring the plasma density information over the long term, a probe for measuring the plasma density information, and a plasma density information measuring apparatus are disclosed. A measuring probe is set such that a tip end of a glass tube of the measuring probe is brought into contact with plasma PM to be measured. High-frequency power sent through a coaxial cable is supplied to the plasma PM from a loop antenna through a wall of the tube, and reflection power of the high-frequency power is received by the loop antenna to obtain a counter frequency variation of reflection coefficient of the high-frequency power. In the obtained reflection coefficient, a portion thereof in which the reflection coefficient is largely reduced is a peak at which strong absorption of high-frequency power is caused due to the plasma density. The plasma density can be obtained from the plasma absorption frequency.
    Type: Application
    Filed: October 10, 2001
    Publication date: April 25, 2002
    Applicant: NISSIN INC.
    Inventors: Hideo Sugai, Seiichi Takasuga, Naoki Toyoda
  • Publication number: 20020039006
    Abstract: For insertion into a lamp housing, a radiator module (1) is provided inside of the module with at least one discharge lamp as radiation source, which puts out an ultraviolet radiation produced by plasma within a discharge chamber (2), the plasma being formed by coupling an electromagnetic field into the discharge chamber (2) and the radiation produced by the plasma exits along a given optical axis through at least one body (12) transparent to ultraviolet radiation as a window. In the range of the plasma at least one diaphragm opaque to radiation is provided with a through-bore along the axis (6), an additional thermal radiation source is fixedly arranged in a given position within the module along the optical axis (6); the additionally produced radiation penetrates through a second transparent body (13) as entry window into the discharge chamber, and then exits along the axis through the first transparent body (12) together with the ultraviolet radiation produced by the plasma.
    Type: Application
    Filed: November 30, 2000
    Publication date: April 4, 2002
    Inventors: Beate Herter, Anke Schnabl, Karsten Ernesti, Dieter Steck
  • Patent number: 6351075
    Abstract: A plasma processing apparatus includes at least one pair of a first rotary permanent magnet system (1) and a second rotary permanent magnet system (2) The rotary permanent magnet systems further include individual permanent magnets (3) and are positioned opposite to each other. The individual permanent magnets (3) have a maximum magnetic induction of more than 10−1 Tesla. Additionally a driver system (4) for driving a motion of the rotary magnet systems (1, 2) is used in combination with a basic plasma processing device (5). By means of the rotary permanent magnet systems time variable magnetic flux lines (6) will be formed for affecting the plasma (7) produced by the plasma processing device (5).
    Type: Grant
    Filed: August 8, 2000
    Date of Patent: February 26, 2002
    Inventors: Hana Barankova, Ladislav Bardos
  • Patent number: 6293090
    Abstract: A radio frequency (RF) plasma thruster for use in electric propulsion for spacecraft. The thruster operates by heating plasma in a magnetic field, which then flows out along magnetic field lines, producing axial thrust. The present invention greatly increases the efficiency of the RF plasma thruster compared to previous thrusters of this type, while retaining the advantages of RF plasma thrusters over other types of electric and chemical propulsion systems. The present invention utilizes a lower hybrid wave for heating of the electrons, rather than electron cyclotron resonance (ECR) heating. The lower hybrid wave is used because it creates high-density plasmas and the antennas used to couple RF energy to the plasma are relatively simple to construct. This allows much better efficiency because no hot electron population is created to siphon off much of the RF power applied to the plasma.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: September 25, 2001
    Assignee: New England Space Works, Inc.
    Inventor: Lynn B. Olson
  • Publication number: 20010017524
    Abstract: A plasma processing system includes a processing vessel for housing therein an object to be processed. In the upper portion of the processing vessel, a substantially disk-shaped electrode plate having a facing surface facing the object is provided. A radio-frequency wave supply unit supplies radio-frequency waves having a flattened waveform which forms substantially a sinusoidal wave whose crest and trough portions are substantially horizontally flattened. The radio-frequency waves supplied from the supply unit are propagated in diametrically opposite directions on the facing surface of the electrode to form standing waves. Similar to the supplied radio-frequency waves, the standing waves also have a waveform which forms substantially a sinusoidal wave whose crest and trough portions are substantially horizontally flattened.
    Type: Application
    Filed: February 22, 2001
    Publication date: August 30, 2001
    Applicant: TOKYO ELECTRON LIMITED
    Inventor: Nobuo Ishii
  • Patent number: 6265831
    Abstract: A tendency for a discontinuity to occur in the amount of power reflected back to an r.f. bias source of a vacuum plasma processor is overcome by controlling the r.f. bias source output power so the power delivered to plasma in a vacuum processing chamber remains substantially constant. The r.f bias source output power is changed much faster than changes in capacitors of a matching network connecting the r.f. bias power source to an electrode of a workpiece holder processor. A capacitive impedance component of the plasma is determined by optically measuring the thickness of a plasma sheath in the chamber.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: July 24, 2001
    Assignee: Lam Research Corporation
    Inventors: Arthur M. Howald, John P. Holland, Christopher Olson
  • Patent number: 6262539
    Abstract: Apparatus for feeding a target into a chamber of a cathode arc source comprises support structure (22, 23, 24) attached to or integral with the cathode arc source (10), a cathode station (16, 17, 18) for receiving a target (18) in electrical connection with an arc power supply, wherein the cathode station is mounted for movement (21, 37) on the support structure relative to the chamber so as to feed the target into the chamber. The apparatus can also have a target cutter in the chamber for removing an upper portion of the target. A graphite target for feeding into the source is a composite of at least inner and outer sections, the inner section comprising graphite powder and having a density in the range 1.7-2.0 g/cm3 and the outer section comprising graphite powder and having a density that is at least 0.1 g/cm3 less than that of the inner section.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: July 17, 2001
    Assignee: Filplas Vacuum Technology PTE Ltd
    Inventors: Xu Shi, Beng Kang Tay, Hong Siang Tan
  • Patent number: 6262523
    Abstract: Large area atmospheric-pressure plasma jet. A plasma discharge that can be operated at atmospheric pressure and near room temperature using 13.56 MHz rf power is described. Unlike plasma torches, the discharge produces a gas-phase effluent no hotter than 250° C. at an applied power of about 300 W, and shows distinct non-thermal characteristics. In the simplest design, two planar, parallel electrodes are employed to generate a plasma in the volume therebetween. A “jet” of long-lived metastable and reactive species that are capable of rapidly cleaning or etching metals and other materials is generated which extends up to 8 in. beyond the open end of the electrodes. Films and coatings may also be removed by these species. Arcing is prevented in the apparatus by using gas mixtures containing He, which limits ionization, by using high flow velocities, and by properly spacing the rf-powered electrode.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: July 17, 2001
    Assignee: The Regents of the University of California
    Inventors: Gary S. Selwyn, Ivars Henins, Steve E. Babayan, Robert F. Hicks
  • Patent number: 6213050
    Abstract: A novel plasma treatment system (200) including one or more novel computer codes. These codes provide a high density plasma for plasma immersion ion implantation applications.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: April 10, 2001
    Assignee: Silicon Genesis Corporation
    Inventors: Wei Liu, Michael A. Bryan, Ian S. Roth
  • Patent number: 6211621
    Abstract: A microwave energy plasma source comprises a cylinder with a top lid that allows a centrally located plasma tube to be supplied with a process gas. On opposite sides of the cylinder walls are located a pair of push-pull air fans that provide a cooling air flow through the inside chamber of the cylinder. Orthogonal to the pair of fans, a microwave energy applicator is mounted to the cylinder walls and has a ring type slow wave structure which surrounds the plasma tube. The bottoms of the cylinder and the plasma tube are connected through a coupler to a process chamber in which is situated a semiconductor wafer being processed. In alternative embodiments, the cylinder has included a movable planar floor and ceiling between which is formed a tunable microwave cavity. Such top and bottom tuning plates are adjusted such that the microwave source impedance is optimally matched to the microwave applicator terminating impedance by affecting the tuned frequency of the ring type slow wave structure.
    Type: Grant
    Filed: March 18, 1999
    Date of Patent: April 3, 2001
    Assignee: GaSonics International
    Inventors: James W. Caughran, Terry L. White, Daniel G. Nagal, Sidney Hung Luu
  • Patent number: 6211622
    Abstract: A plurality of extracting orifices 42 for extracting the electron beam from a discharge portion 2 into a plasma process chamber 3 via a compartment 4 are provided radially. A plurality of accelerating electrodes 36, 37 are arranged in the process chamber 3. The electron extracting direction from the extracting orifices 42 is set in substantially parallel with an object surface 35. The number and the arrangement of the accelerating electrodes 36, 37 are set such that a density distribution of the excited plasma has an oprimal state for processing the object. The object having a large area can be processed appropriately.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: April 3, 2001
    Assignee: Kawasaki Jukogyo Kabushiki Kaisha
    Inventors: Makoto Ryoji, Takeshi Hasegawa, Masahito Ban, Yukitaka Mori
  • Patent number: 6204605
    Abstract: Voltage is applied to conducting loops wrapped around the outside of a non-conducting chamber (e.g., a glass tube) to generate a capacitively coupled discharge plasma inside the chamber. In one embodiment, a seed gas is injected into the chamber through an inlet in an otherwise closed end of the chamber, while the other end is open to the ambient atmosphere. In such an embodiment, the seed gas is used to ignite the plasma in air at essentially atmospheric pressure. The present invention has different applications, including, but not limited to, (a) passivating toxic or polluting gases that are injected into the chamber along with the seed gas and (b) treating materials placed within a second chamber that is connected to the open end of the plasma-generating chamber such that active species migrate into the second chamber to interact with the materials placed therein.
    Type: Grant
    Filed: March 24, 1999
    Date of Patent: March 20, 2001
    Assignee: The University of Tennessee Research Corporation
    Inventors: Mounir Laroussi, Gary S. Sayler, Battle B. Glascock
  • Patent number: 6194836
    Abstract: The invention relates to a device for generating a magnetic field {right arrow over (B)}, comprising a multi-pole structure (M1, M2, M3) in which the elements have polarities such that the vector sum of the fields created at each point by each of these elements is sufficient to define at least one closed line of minima B inside a surface with constant modulus (70) closed in the space. Application for an ECR source.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: February 27, 2001
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Jean-Yves Pacquet, Renan Leroy
  • Patent number: 6175183
    Abstract: A device for producing plasma in a vacuum chamber (13) with the help of electromagnetic alternating fields, in which a rod-shaped conductor (3) that is inside a pipe (2) and is made of an insulating material and is guided into the vacuum chamber (13). The inner diameter of the insulating pipe (2) is larger than the diameter of the conductor (3). The insulating pipe (2) is held in the wall (1) of the vacuum chamber (13) at one end, and its outer surface is sealed across from the vacuum chamber wall. The conductor (3) is connected to a source (9) for producing the electromagnetic alternating field. A pipe-shaped conductor (4) extends coaxially to the rod-shaped conductor (3) in the annulus formed by the rod-shaped conductor (3) and the insulating pipe (2), whereby the radial inner ring slot (14) formed between the rod-shaped conductor (3) and the pipe-shaped conductor (4) corresponds to the waveguide (10) of the source (9).
    Type: Grant
    Filed: May 20, 1999
    Date of Patent: January 16, 2001
    Assignee: Leybold Systems GmbH
    Inventor: Michael Liehr