Patents Represented by Attorney, Agent or Law Firm Roland Tso
  • Patent number: 6716765
    Abstract: A method useful for the cleaning of the inner surfaces, including the deposition station or showerhead area of a deposition chamber, are described herein. According to one embodiment of the invention, a fluorine-containing source gas, such as NF3, SF6, or C2F6, for example, is supplied to the deposition chamber, and energized by a radio frequency to form a plasma that contains fluorine atoms and ions. The radio frequency power is modulated between a maximum value (for a “plasma-ON period”) and a minimum value of zero (for a “plasma-OFF period”) at a frequency from about 150 Hz to about 50 kHz and a duty cycle of from about 40% to about 90%. The maximum value of RF power may be from about 300 to about 2500 Watts per deposition station or showerhead, and the minimum value is typically zero. The modulated-RF clean process may be conducted in situ after the deposition of a film on wafers, and may be followed by a conventional continuous-RF clean process.
    Type: Grant
    Filed: November 12, 2002
    Date of Patent: April 6, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Aree Hanprasopwattana, Edward J. Augustyniak, Jason L. Tian, Bart J. Van Schravendijk
  • Patent number: 6693043
    Abstract: A unique photoresist strip sequence using a downstream plasma system is described. The sequence can include a RF directional plasma alone, downstream plasma alone or combine both RF plasma and downstream plasma together. The process sequence can be a single step or multiple steps, which produce high strip rates while maintaining the dielectric properties of the film. The process can be an oxidizing process carried out at low temperature and low pressure, which reduces the reactivity of the oxygen with the low-k film. Furthermore, by adding a small percentage of an additive gas, such as a fluorine-containing gas, to the plasma, the inorganic residues from the strip process are removed, leaving a clean film cleared of photoresist and residue.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: February 17, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Senzi Li, Helmuth Treichel, Kirk Ostrowski, Chevan Goonetilleke, Jim Su, David L. Chen
  • Patent number: 6660245
    Abstract: Structure-directing agents, such as quaternary ammonium, are removed from silicalite or zeolite crystals by oxidative attack (e.g., using CO2, H2O or NH3) first, by using a combination of ammonia, water and hydrogen peroxide at an elevated temperature; second, by using choline, hydrogen peroxide and a surfactant; third, by using ozonated water; and fourth, by exposing the crystals to an oxygen-containing plasma. Thin porous films of silicalite or zeolite crystals are useful, for example, in forming low dielectric constant insulating layers in semiconductor chip fabrication. In order for the silicalite or zeolite crystals to form a low dielectric constant film, however, the entrained molecules of the structure-directing agent must be removed.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: December 9, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Justin F. Gaynor, Patrick Vancleemput
  • Patent number: 6589401
    Abstract: An apparatus for electroplating a wafer surface includes a cup having a central aperture defined by an inner perimeter, a compliant seal adjacent the inner perimeter, contacts adjacent the compliant seal and a cone attached to a rotatable spindle. The compliant seal forms a seal with the perimeter region of the wafer surface preventing plating solution from contaminating the wafer edge, wafer backside and the contacts. As a further measure to prevent contamination, the region behind the compliant seal is pressurized. By rotating the wafer during electroplating, bubble entrapment on the wafer surface is prevented. Further, the contacts can be arranged into banks of contacts and the resistivity between banks can be tested to detect poor electrical connections between the contacts and the wafer surface.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: July 8, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Evan E. Patton, Wayne Fetters
  • Patent number: 6569299
    Abstract: An anode includes an anode cup, a membrane and ion source material, the anode cup and membrane forming an enclosure in which the ion source material is located. The anode cup includes a base section having a central aperture and the membrane also has a central aperture. A jet is passed through the central apertures of the base section of the anode cup and through the membrane allowing plating solution to be directed at the center of a wafer being electroplated.
    Type: Grant
    Filed: May 18, 2000
    Date of Patent: May 27, 2003
    Assignees: Novellus Systems, Inc., International Business Machines, Corp.
    Inventors: Jonathan David Reid, Robert J. Contolini, John Owen Dukovic
  • Patent number: 6561796
    Abstract: Bowing of semiconductor wafers during heating is reduced by heating the wafers in a gas with a thermal conductivity and mean free path greater than that of oxygen, or by heating the wafers in a processing chamber under a pressure less than 0.1 Torr. In one embodiment, the high thermal conductivity gas is helium and heating in the helium takes place at a pressure less than 2.4 Torr.
    Type: Grant
    Filed: September 6, 2000
    Date of Patent: May 13, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Martin M. Barrera, George Kamian, Edward J. McInerney, Craig L. Stevens
  • Patent number: 6521106
    Abstract: Sputtering apparatus using a collimating filter to limit the angles at which sputtered particles will reach the surface of the substrate or workpiece being processed is shown. The sputtering apparatus relies on a combination of a planar sputter source larger in size than the workpiece and having highly uniform emission characteristics across the much of its surface, including its center; a collimating filter; and low operating pressure to avoid scattering of sputtered atoms after they have passed through the collimation filter. In the preferred embodiment, the collimation filter is made from a material which has substantially the same thermal coefficient of expansion as the film which is deposited on the substrate. In one specific embodiment, a titanium collimation filter is used when the sputtering system is used to deposit films of titanium, titanium nitride or titanium/tungsten alloy.
    Type: Grant
    Filed: June 18, 1996
    Date of Patent: February 18, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Geri M. Actor, Ronald R. Cochran, Vance E. Hoffman, Jr.
  • Patent number: 6461155
    Abstract: A heater for heating a substrate in a supercritical fluid reactor includes a heater body having a heater chamber initially open to the interior of the reactor. The heater chamber is sized to match the substrate and includes a seal around its perimeter that seals against the perimeter of the substrate and forms a closed heater chamber with the backside of the substrate. A heating element, insulated from the heater body, preferably with pyrolytic graphite, is located in the heater chamber to heat the substrate from the backside. A clamp ring with a seal around its inner perimeter cooperates with the heater body to seal the substrate to the heater body. The heater is preferably spaced apart from the substrate, as well as the walls of the eater chamber and the insulator, to provide uniform heating by transferring heat through the supercritical fluid.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: October 8, 2002
    Assignee: Novellus Systems, Inc.
    Inventor: E. Derryck Settles
  • Patent number: 6333268
    Abstract: Adherent matrix layers such as post-etch and other post-process residues are removed from a substrate by exposing them to a vapor phase solvent to allow penetration of the vapor phase solvent into the adherent matrix layers and condensing the vapor phase solvent into the adherent matrix layers and revaporized to promote fragmentation of the matrix and facilitate removal. Megasonic energy may be transmitted via a transmission member to the adherent matrix through the solvent condensed thereon to loosen fragments and particles. The substrate is typically rotated to improve contact between the megasonic energy transmission member and the condensed solvent and achieve more uniform cleaning. A co-solvent which is soluble in the vapor phase solvent may be added to enhance removal of specific adherent matrix materials.
    Type: Grant
    Filed: August 1, 2000
    Date of Patent: December 25, 2001
    Assignee: Novellus Systems, Inc.
    Inventors: Vladimir Starov, Shmuel Erez, Syed S. Basha, Arkadiy I. Shimanovich, Ravi Vellanki, Krishnan Shrinivasan, Karen A. Reinhardt, Aleksandr Kabansky
  • Patent number: 6287643
    Abstract: An apparatus and method for injecting gas within a plasma reactor and tailoring the distribution of an active species generated by the remote plasma source over the substrate or wafer. The distribution may be uniform, wafer-edge concentrated, or wafer-center concentrated. A contoured plate or profiler modifies the distribution. The profiler is an axially symmetric plate, having a narrow top end and a wider bottom end, shaped to redistribute the gas flow incident upon it. The method for tailoring the distribution of the active species over the substrate includes predetermining the profiler diameter and adjusting the profiler height over the substrate.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: September 11, 2001
    Assignee: Novellus Systems, Inc.
    Inventors: Ronald Allan Powell, Gabriel I. Font-Rodriguez, Simon Selitser, Emerson Derryck Settles
  • Patent number: 6258653
    Abstract: A method of making a capacitor on a conductive surface, preferably on a polysilicon surface includes contamination cleaning the surface with a high density plasma (HDP) of a first gaseous agent, such as hydrogen, then growing a silicon nitride barrier layer on the surface using a high density plasma (HDP) of nitrogen. A layer of tantalum oxide is then deposited on the silicon nitride layer to form a capacitor dielectric layer. A second silicon nitride layer is then grown on the capacitor dielectric layer, also using an HDP nitrogen plasma with the addition of a silicon containing gas, such as silane. Finally, a conductive layer is deposited on the second silicon nitride layer to form the capacitor. The HDP plasma is heated using an inductively coupled radio frequency generator. The invention also includes a capacitor constructed on a conductive surface by the method of the invention.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: July 10, 2001
    Assignee: Novellus Systems, Inc.
    Inventors: Kok Heng Chew, Patrick van Cleemput, Kathy Konjuh, Tirunelveli Subramaniam Ravi
  • Patent number: 6228779
    Abstract: A dense and stable dielectric layer of silicon nitride and silicon dioxide suitable for use in transistors of ULSI circuits is fabricated by a high pressure process in which a nitride layer is first formed on a surface of a silicon substrate and then a silicon dioxide layer is formed on the silicon surface under the nitride layer. By placing the nitride layer above the silicon dioxide and next to a doped polysilicon gate, diffusion of dopant ions such as boron from the gate into the silicon dioxide is reduced. As semiconductor devices are scaled down, the thermal budget required for the process steps is reduced.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: May 8, 2001
    Assignee: Novellus Systems, Inc.
    Inventors: John A. Bloom, Dim-Lee Kwong, Robert K. Evans, Bruce T. Acker
  • Patent number: 6225169
    Abstract: A method of constructing a gate dielectric on a semiconductor surface includes cleaning a silicon surface then growing a silicon nitride barrier layer on the silicon surface using a high density plasma (HDP) of nitrogen. A gate dielectric layer is then deposited on the silicon nitride layer and a second silicon nitride layer is then grown on the dielectric layer, also using an HDP nitrogen plasma, followed by deposition of the conductive gate layer. The HDP nitrogen plasma is heated using an inductively coupled radio frequency generator. The invention also includes a gated device including a gate dielectric constructed on a semiconductor surface by the method of the invention.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: May 1, 2001
    Assignee: Novellus Systems, Inc.
    Inventors: Kok Heng Chew, Patrick van Cleemput
  • Patent number: 6217716
    Abstract: Magnetic field lines within a hollow cathode magnetron sputtering device are modified by various means to improve the full-face erosion profile of the hollow cathode target. These means include, varying the magnetic field of the main magnetic source, extending the magnetic field beyond the opening in the hollow cathode and adding a stationary or mobile magnetic field source adjacent to the closed end surface of the hollow cathode target. The present invention employs various embodiments which when implemented individually or in combination improve the full face erosion of a target cathode in a hollow cathode magnetron sputtering source.
    Type: Grant
    Filed: May 6, 1998
    Date of Patent: April 17, 2001
    Assignee: Novellus Systems, Inc.
    Inventor: Kwok Fai Lai
  • Patent number: 6024843
    Abstract: A magentron sputtering apparatus includes a rotatable magnet which is either concave or convex. For one magnet structure, at least a portion of the centerline of the magnet lies along a curve defined by ##EQU1## where .xi.(r) is a preselected erosion profile. When stationary, the magnet generates a localized magnetic field of approximately constant width. In operation, when the magnet is rotated, it generates the preselected erosion profile in the target. The preselected erosion profile may be constant.
    Type: Grant
    Filed: August 27, 1992
    Date of Patent: February 15, 2000
    Assignee: Novellus Systems, Inc.
    Inventors: Robert L. Anderson, John C. Helmer
  • Patent number: 6022416
    Abstract: A point-of-use vaporization system for use in Chemical Vapor Deposition having a first delivery member for delivering a liquid precursor to a vaporization point, a second delivery member for separately delivering a solvent to the vaporization point, and a frit for vaporizing the precursor and solvent at the vaporization point.
    Type: Grant
    Filed: April 23, 1998
    Date of Patent: February 8, 2000
    Assignee: Novellus Systems, Inc.
    Inventor: Darin S. Olson
  • Patent number: 5985115
    Abstract: An internally cooled target assembly for use in a magnetron sputtering apparatus is provided. The internally cooled target assembly includes a cooling plate that is configured to promote highly turbulent coolant flow through the target assembly to achieve efficient and uniform target cooling. The volume of coolant required to cool the target assembly is minimized.
    Type: Grant
    Filed: April 11, 1997
    Date of Patent: November 16, 1999
    Assignee: Novellus Systems, Inc.
    Inventors: Larry D. Hartsough, David J. Harra, Ronald R. Cochran, Mingwei Jiang