Patents by Inventor Steven T. Mayer

Steven T. Mayer 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: 6946065
    Abstract: Several techniques are described for reducing or mitigating the formation of seams and/or voids in electroplating the interior regions of microscopic recessed features. Cathodic polarization is used to mitigate the deleterious effects of introducing a substrate plated with a seed layer into an electroplating solution. Also described are diffusion-controlled electroplating techniques to provide for bottom-up filling of trenches and vias, avoiding thereby sidewalls growing together to create seams/voids. A preliminary plating step is also described that plates a thin film of conductor on the interior surfaces of features leading to adequate electrical conductivity to the feature bottom, facilitating bottom-up filling.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: September 20, 2005
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Vijay Bhaskaran, Evan E. Patton, Robert L. Jackson, Jonathan Reid
  • Patent number: 6919010
    Abstract: A substantially uniform layer of a metal is electroplated onto a work piece having a seed layer thereon. The current of a plating cell is provided from an azimuthally asymmetric anode, which is rotated with respect to the work piece (i.e., either or both of the work piece and the anode may be rotating). The azimuthal asymmetry provides a time-of-exposure correction to the current distribution reaching the work piece, whereby peripheral regions of the work piece see less current than central regions over the period of rotation. In some embodiments, the total current is distributed among a plurality of anodes in the plating cell in order to tailor the current distribution in the plating electrolyte over time. Focusing elements may be used to create “virtual anodes” in proximity to the plating surface of the work piece to further control the current distribution in the electrolyte during plating.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: July 19, 2005
    Assignee: Novellus Systems, Inc.
    Inventor: Steven T. Mayer
  • Patent number: 6890416
    Abstract: An electroplating apparatus prevents anode-mediated degradation of electrolyte additives by creating a mechanism for maintaining separate anolyte and catholyte and preventing mixing thereof within a plating chamber. The separation is accomplished by interposing a porous chemical transport barrier between the anode and cathode. The transport barrier limits the chemical transport (via diffusion and/or convection) of all species but allows migration of ionic species (and hence passage of current) during application of sufficiently large electric fields within electrolyte.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: May 10, 2005
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Evan E. Patton, Robert L. Jackson, Jonathan D. Reid
  • Patent number: 6821407
    Abstract: An electroplating system includes (a) a phosphorized anode having an average grain size of at least about 50 micrometers and (b) plating apparatus that separates the anode from the cathode and prevents most particles generated at the anode from passing to the cathode. The separation may be accomplished by interposing a microporous chemical transport barrier between the anode and cathode. The relatively few particles that are generated at the large grain phosphorized copper anode are prevented from passing into the cathode (wafer) chamber area and thereby causing a defect in the part.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: November 23, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Jonathan D. Reid, Timothy Mark Archer, Thomas Tan Vu, Seshasayee Varadarajan, Jon Henri, Steven T. Mayer, David Sauer, Anita Kang, Gerald Feldewerth
  • Patent number: 6800187
    Abstract: An apparatus for engaging a work piece during plating facilitates electrolyte flow during a plating operation. The apparatus helps to control the plating solution fluid dynamics and electric field shape to keep the wafer's local plating environment uniform and bubble free. The apparatus holding the work piece in a manner that facilitates electrolyte circulation patterns in which the electrolyte flows from the center of the work piece plating surface, outward toward the edge of the edge of the work piece. The apparatus holds the work piece near the work piece edges and provides a flow path for electrolyte to flow outward away from the edges of the work piece plating surface. That flow path has a “snorkel” shape in which the outlet is higher than the inlet. In addition, the flow path may have a slot shape that spans much or all of the circumference of holding apparatus. It may be made from a material that resists deformation and corrosion such as certain ceramics.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: October 5, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Jonathan D. Reid, Steven T. Mayer, R. Marshall Stowell, Evan E. Patton, Jeff A. Hawkins
  • Patent number: 6793796
    Abstract: Electroplating methods using an electroplating bath containing metal ions and a suppressor additive, an accelerator additive, and a leveler additive, together with controlling the current density applied to a substrate, avoid defects in plated films on substrates having features with a range of aspect ratios, while providing good filling and thickness distribution. The methods include, in succession, applying DC cathodic current densities optimized to form a conformal thin film on a seed layer, to provide bottom-up filling, preferentially on features having the largest aspect ratios, and to provide conformal plating of all features and adjacent field regions. Including a leveling agent in the electroplating bath produces films with better quality after subsequent processing.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: September 21, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Jonathan D. Reid, David Smith, Steven T. Mayer, Jon Henri, Sesha Varadarajan
  • Patent number: 6773571
    Abstract: The present invention pertains to methods and apparatus for electroplating a substantially uniform layer of a metal onto a work piece having a seed layer thereon. The total current of a plating cell is distributed among a plurality of anodes in the plating cell in order to tailor the current distribution in the plating electrolyte to compensate for resistance and voltage variation across a work piece due to the seed layer. Focusing elements are used to create “virtual anodes” in proximity to the plating surface of the work piece to further control the current distribution in the electrolyte during plating.
    Type: Grant
    Filed: May 22, 2002
    Date of Patent: August 10, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Evan E. Patton, Brian Paul Blackman, Jonathan D. Reid, Thomas Anand Ponnuswamy, Harold D. Perry
  • Patent number: 6755946
    Abstract: The present invention includes apparatus and methods for measuring impedance of a layer of deposited metal on a substrate and controlling deposition uniformity during electroplating. A first circuit delivers plating current to a metal layer on the substrate, and a second circuit, electrically isolated from the first, measures the impedance. Methods of the invention provide multi-point sheet resistance measurements before and during an electroplating process on a substrate. In a specific example, resistance is measured via a copper seed layer during electroplating.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: June 29, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Evan E. Patton, Jonathan D. Reid, Jeffrey A. Hawkins, Dinesh S. Kalakkad, Steven T. Mayer
  • Patent number: 6755954
    Abstract: An apparatus for electrochemical treatment of a substrate, in particular for electroplating an integrated circuit wafer. An apparatus preferably includes dynamically operable concentric anodes and dielectric shields in an electrochemical bath. Preferably, the bath height of an electrochemical bath, the substrate height, and the shape and positions of an insert shield and a diffuser shield are dynamically variable during electrochemical treatment operations. Step include varying anode current, bath height and substrate height, shield shape, and shield position.
    Type: Grant
    Filed: April 4, 2002
    Date of Patent: June 29, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Timothy Patrick Cleary, Michael John Janicki, Edmund B. Minshall, Thomas A. Ponnuswamy
  • Publication number: 20040065540
    Abstract: A treating head having a treating surface and a substrate treatment surface define a thin fluid gap that is filled with reactant liquid to form a thin liquid layer on the substrate for conducting a liquid chemical reaction treatment or other liquid treatment of the substrate. The thin liquid layer has a volume in a range of about from 50 ml to 500 ml. Preferably, the chemical composition, temperature, and other properties of liquid in the thin liquid layer are dynamically variable.
    Type: Application
    Filed: June 30, 2003
    Publication date: April 8, 2004
    Applicant: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Jonathan D. Reid, Timothy Patrick Cleary, Edmund B. Minshall, R. Marshall Stowell, Heung Lak Park
  • Patent number: 6713122
    Abstract: Methods and apparatus for reducing heat load and air exposure when using an electroless plating fluid during a plating process, are presented. An electroless plating apparatus, including an electroless plating vessel and recirculation systems, is presented. The electroless plating vessel minimizes air exposure (and thus evaporative cooling and degradation) of the electroless plating fluid while the recirculation systems minimize heat load of the electroless plating fluid.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: March 30, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, John B. Alexy, Jingbin Feng
  • Patent number: 6709565
    Abstract: The present invention pertains to apparatus and methods for planarization of metal surfaces having both recessed and raised features, over a large range of feature sizes. The invention accomplishes this by increasing the fluid agitation in raised regions with respect to recessed regions. That is, the agitation of the electropolishing bath fluid is agitated or exchanged as a function of elevation on the metal film profile. The higher the elevation, the greater the movement or exchange rate of bath fluid. In preferred methods of the invention, this agitation is achieved through the use of a microporous electropolishing pad that moves over (either near or in contact with) the surface of the wafer during the electropolishing process. Thus, methods of the invention are electropolishing methods, which in some cases include mechanical polishing elements.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: March 23, 2004
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Robert J. Contolini, Eliot K. Broadbent, John S. Drewery
  • Patent number: 6664122
    Abstract: Disclosed is a procedure for deposition of a thin and relatively continuous electroless copper film on the substrate of sub-micron integrated circuit features. The electroless copper film is deposited onto a previously deposited PVD copper film, which may be discontinuous. The continuous film formed by electroless deposition allows for sufficient filling of the sub-micron integrated circuit features by electrodeposition. The electroless bath employed to form the continuous electroless copper film may be composed of a reducing agent, a complexing agent, a source of copper ions, a pH adjuster, and optionally one or more surfactants and/or stabilizers. In one example, the reducing agent contains an aldehyde moiety.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: December 16, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Tatyana N. Andryuschenko, Jonathan D. Reid, Steven T. Mayer, Eric G. Webb
  • Patent number: 6586342
    Abstract: Chemical etching methods and associated modules for performing the removal of metal from the edge bevel region of a semiconductor wafer are described. The methods and systems apply liquid etchant in a precise manner at the edge bevel region of the wafer under viscous flow conditions, so that the etchant is applied on to the front edge area and flows over the side edge and onto the back edge in a viscous manner. The etchant thus does not flow or splatter onto the active circuit region of the wafer. An edge bevel removal embodiment involving that is particularly effective at obviating streaking, narrowing the metal taper and allowing for subsequent chemical mechanical polishing, is disclosed.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: July 1, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Seshasayee Varadarajan, Andrew J. McCutcheon
  • Patent number: 6562204
    Abstract: Controlled-potential electroplating provides an effective method of electroplating metals onto the surfaces of high aspect ratio recessed features of integrated circuit devices. Methods are provided to mitigate corrosion of a metal seed layer on recessed features due to contact of the seed layer with an electrolyte solution. The potential can also be controlled to provide conformal plating over the seed layer and bottom-up filling of the recessed features. For each of these processes, a constant cathodic voltage, pulsed cathodic voltage, or ramped cathodic voltage can be used. An apparatus for controlled-potential electroplating includes a reference electrode placed near the surface to be plated and at least one cathode sense lead to measure the potential at points on the circumference of the integrated circuit structure.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: May 13, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Jonathan Reid, Robert Contolini
  • Publication number: 20030079995
    Abstract: In an electrochemical reactor used for electrochemical treatment of a substrate, for example, for electroplating or electropolishing the substrate, one or more of the surface area of a field-shaping shield, the shield's distance between the anode and cathode, and the shield's angular orientation is varied during electrochemical treatment to screen the applied field and to compensate for potential drop along the radius of a wafer. The shield establishes an inverse potential drop in the electrolytic fluid to overcome the resistance of a thin film of conductive metal on the wafer.
    Type: Application
    Filed: October 21, 2002
    Publication date: May 1, 2003
    Applicant: Novellus Systems, Inc.
    Inventors: Robert J. Contolini, Andrew J. McCutcheon, Steven T. Mayer
  • Patent number: 6551487
    Abstract: The orientation of a wafer with respect to the surface of an electrolyte is controlled during an electroplating process. The wafer is delivered to an electrolyte bath along a trajectory normal to the surface of the electrolyte. Along this trajectory, the wafer is angled before entry into the electrolyte for angled immersion. A wafer can be plated in an angled orientation or not, depending on what is optimal for a given situation. Also, in some designs, the wafer's orientation can be adjusted actively during immersion or during electroplating, providing flexibility in various electroplating scenarios.
    Type: Grant
    Filed: May 31, 2001
    Date of Patent: April 22, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Jonathan D. Reid, Steven T. Mayer, Seshasayee Varadarajan, David C. Smith, Evan E. Patton, Dinesh S. Kalakkad, Gary Lind
  • Patent number: 6551483
    Abstract: Controlled-potential electroplating provides an effective method of electroplating metals onto the surfaces of high aspect ratio recessed features of integrated circuit devices. Methods are provided to mitigate corrosion of a metal seed layer on recessed features due to contact of the seed layer with an electrolyte solution. The potential can also be controlled to provide conformal plating over the seed layer and bottom-up filling of the recessed features. For each of these processes, a constant cathodic voltage, pulsed cathodic voltage, or ramped cathodic voltage can be used. An apparatus for controlled-potential electroplating includes a reference electrode placed near the surface to be plated and at least one cathode sense lead to measure the potential at points on the circumference of the integrated circuit structure.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: April 22, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Jonathan Reid, Robert Contolini
  • Patent number: 6537416
    Abstract: A wafer chuck includes alignment members that allows a semiconductor wafer to be properly aligned on the chuck without using a separate alignment stage. The alignment members may be cams, for example, attached to arms of the wafer chuck. These members may assume an alignment position when a robot arm places the wafer on the chuck. In this position, they guide the wafer into a proper alignment position with respect to the chuck. During rotation at a particular rotational speed, the alignment members move away from the wafer to allow liquid etchant to flow over the entire edge region of the wafer. At still higher rotational speeds, the wafer is clamped into position to prevent it from flying off the chuck. A clamping cam or other device (such as the alignment member itself) may provide the clamping.
    Type: Grant
    Filed: April 25, 2000
    Date of Patent: March 25, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Steve Taatjes, Andy McCutcheon, Jim Schall, Jinbin Feng
  • Patent number: 6527920
    Abstract: An electroplating apparatus prevents anode-mediated degradation of electrolyte additives by creating a mechanism for maintaining separate anolyte and catholyte and preventing mixing thereof within a plating chamber. The separation is accomplished by interposing a porous chemical transport barrier between the anode and cathode. The transport barrier limits the chemical transport (via diffusion and/or convection) of all species but allows migration of ionic species (and hence passage of current) during application of sufficiently large electric fields within electrolyte.
    Type: Grant
    Filed: November 3, 2000
    Date of Patent: March 4, 2003
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Evan E. Patton, Robert L. Jackson, Jonathan D. Reid