Reversing Current Or Voltage Patents (Class 205/103)
  • Publication number: 20020033341
    Abstract: A smooth layer of a metal is electroplated onto a microrough electrically conducting substrate by immersing the substrate and a counterelectrode in an electroplating bath of the metal to be electroplated and passing a modulated reversing electric current between the electrodes. The current contains pulses that are cathodic with respect to said substrate and pulses that are anodic with respect to said substrate. The cathodic pulses have a duty cycle less than about 50% and said anodic pulses have a duty cycle greater than about 50%, the charge transfer ratio of the cathodic pulses to the anodic pulses is greater than one, and the frequency of said pulses ranges from about 10 Hertz to about 12000 Hertz. The plating bath is substantially devoid of levelers and may be devoid of brighteners.
    Type: Application
    Filed: April 3, 2001
    Publication date: March 21, 2002
    Inventors: E. Jennings Taylor, Chengdong Zhou, Jenny J. Sun
  • Patent number: 6350363
    Abstract: A process of making an electric current rectifying device using spatially coupled bipolar electrochemical deposition includes (a) placing at least two electrically conductive substrates, which may be a source of electrically conductive material, or a separate source of electrically conductive material, together with at least one semiconductor into an environment capable of conducting electricity and containing electrodes; (b) aligning the substrates and the semiconductor with respect to the electrodes such that the electrodes are not in contact with the substrates or the semiconductor and such that the material will form a conductive structure between and in contact with the substrates and the semiconductor when an electric field is applied between the electrodes; (c) to form a first electrically conductive structure between and in contact with a first of the substrates and the semiconductor; (d) reversing the polarity of the voltage to form a second electrically conductive structure.
    Type: Grant
    Filed: May 23, 2000
    Date of Patent: February 26, 2002
    Assignee: Drexel University
    Inventor: Jean-Claude Bradley
  • Patent number: 6346181
    Abstract: Disclosed is an Ni-plated layer of biaxial texture, which is formed by electroplating. In the Ni-plated layer,peaks measured on a &thgr;-rocking curve have a FWHM of 7° or less in terms of the misorientation on the c-axis; and peaks measured on &phgr;-scan have a FWHM of 21° or less in terms of the misorientation on the plane formed by the a-axis and the b-axis. Also, a process of electroplating a Ni layer are disclosed. The process comprises forming a Ni-plated layer of biaxial texture under a magnetic field by electroplating and subjecting the Ni-plated layer to thermal treatment to develop the biaxial texture. This electroplating process is expected to give a significant contribution to the development of the electroplating technology and to replace the vacuum deposition used for the preparation of thin film magnetic materials or thin film piezoelectric materials.
    Type: Grant
    Filed: May 16, 2000
    Date of Patent: February 12, 2002
    Assignee: Korea Institute of Machinery and Materials
    Inventors: Kyu Hwan Lee, Hyung-Sik Chung, Sang Ro Lee, Doyon Chang, Yongsoo Jeong, Jaimoo Yoo, Jae-Woong Ko, Hai-Doo Kim
  • Publication number: 20010054557
    Abstract: Excessive evolution of hydrogen in electrolytic deposition of metals on a cathode substrate can be controlled by using a pulsed reverse current. Reverse current pulses interposed between the forward current pulses consume at least some of the nascent hydrogen and prevent the local pH at the cathode surface from becoming excessively alkaline. Control of hydroxide ion concentration by pulsed reverse current alleviates problems caused by reaction of metal-bearing-ions with hydroxide ions generated near the cathode by evolution of hydrogen. The method is useful in depositing functional chromium coatings on electrically conductive substrates from plating baths comprising aqueous solutions of trivalent chromium salts. In such a method the current comprises forward pulses having a duty cycle of from about 50% to about 90% and reverse pulses having a duty cycle of from about 5% to about 30%, and a frequency of from about 5 Hz to about 700 Hz.
    Type: Application
    Filed: June 9, 1997
    Publication date: December 27, 2001
    Inventors: E. JENNINGS TAYLOR, CHENGDONG ZHOU, ROBERT P. RENZ, ERIC C. STORTZ
  • Patent number: 6319384
    Abstract: A smooth layer of a metal is electroplated onto a microrough electrically conducting substrate by immersing the substrate and a counterelectrode in an electroplating bath of the metal to be electroplated and passing a modulated reversing electric current between the electrodes. The current contains pulses that are cathodic with respect to said substrate and pulses that are anodic with respect to said substrate. The cathodic pulses have a duty cycle less than about 50% and said anodic pulses have a duty cycle greater than about 50%, the charge transfer ratio of the cathodic pulses to the anodic pulses is greater than one, and the frequency of said pulses ranges from about 10 Hertz to about 12000 Hertz. The plating bath is substantially devoid of levelers and may be devoid of brighteners.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: November 20, 2001
    Assignee: Faraday Technology Marketing Group, LLC
    Inventors: E. Jennings Taylor, Chengdong Zhou, Jenny J. Sun
  • Publication number: 20010035354
    Abstract: Deposition of conductive material on or removal of conductive material from a wafer frontal side of a semiconductor wafer is performed by providing an anode having an anode area which is to face the wafer frontal side, and electrically connecting the wafer frontal side with at least one electrical contact, outside of the anode area, by pushing the electrical contact and the wafer frontal side into proximity with each other. A potential is applied between the anode and the electrical contact, and the wafer is moved with respect to the anode and the electrical contact. Full-face electroplating or electropolishing over the wafer frontal side surface, in its entirety, is thus permitted.
    Type: Application
    Filed: December 14, 2000
    Publication date: November 1, 2001
    Applicant: Nu Tool Inc.
    Inventors: Jalal Ashjaee, Boguslaw A. Nagorski, Bulent M. Basol, Homayoun Talieh, Cyprian Uzoh
  • Patent number: 6309528
    Abstract: A continuous layer of a metal is electrodeposited onto a substrate having both hydrodynamically inaccessible recesses and hydrodynamically accessible recesses on its surface by a two-step process in which the hydrodynamically inaccessible recesses are plated using a pulsed reversing current with cathodic pulses having a duty cycle of less than about 50% and anodic pulses having a duty cycle of greater than about 50% and the hydrodynamically accessible recesses are then plated using a pulsed reversing current with cathodic pulses having a duty cycle of greater than about 50% and anodic pulses having a duty cycle of less than about 50%.
    Type: Grant
    Filed: October 18, 1999
    Date of Patent: October 30, 2001
    Assignee: Faraday Technology Marketing Group, LLC
    Inventors: E. Jennings Taylor, Jenny J. Sun, Maria E. Inman
  • Patent number: 6303014
    Abstract: A layer of a metal is electroplated onto an electrically conducting substrate having a generally smooth surface with a small recess therein, having a transverse dimension not greater than about 350 micrometers, by immersing the substrate and a counterelectrode in an electroplating bath of the metal to be electroplated and passing a modulated reversing electric current between the electrodes. The current contains pulses that are cathodic with respect to said substrate and pulses that are anodic with respect to said substrate. The cathodic pulses have a duty cycle less than about 50% and said anodic pulses have a duty cycle greater than about 50%, the charge transfer ratio of the cathodic pulses to the anodic pulses is greater than one, and the frequency of said pulses ranges from about 10 Hertz to about 12000 Hertz. The plating bath may be substantially devoid of levelers and/or brighteners.
    Type: Grant
    Filed: April 20, 2000
    Date of Patent: October 16, 2001
    Assignee: Faraday Technology Marketing Group, LLC
    Inventors: E. Jennings Taylor, Jenny J. Sun, Chengdong Zhou
  • Publication number: 20010023829
    Abstract: A method for plating an electrically conductive substance, which includes the steps of contacting the electrically conductive substance with a plating agent in dilute solution, in which the plating agent is present in a concentration of 200 mM at most, and subjecting the plating agent adjacent to the electrically conducive substance to an electric field.
    Type: Application
    Filed: March 1, 2001
    Publication date: September 27, 2001
    Applicant: Obducat AB
    Inventors: Lennart Olsson, Babak Heidari
  • Publication number: 20010015321
    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: Application
    Filed: February 28, 2001
    Publication date: August 23, 2001
    Inventors: Jonathan D. Reid, David Smith, Steven T. Mayer, Jon Henri, Sesha Varadarajan
  • Publication number: 20010013472
    Abstract: A method of plating for filling via holes, in which each via hole formed in an insulation layer covering a substrate so as to expose, at its bottom, part of a conductor layer located on the substrate, is plated with copper, to be filled with the plated metal, the method comprising the steps of forming a copper film on the top surface of the insulation layer covering the substrate, and the side walls and bottoms of the respective via holes, immersing the substrate having the copper film formed in an aqueous solution containing a plating promoter to thereby deposit the plating promoter on the surface of the copper film, removing the plating promoter from the surface of the copper film located on the insulation layer and leaving the plating promoter on the side walls and bottoms of the respective via holes, and subsequently electroplating the substrate having the copper film formed with copper to thereby fill the via holes with the plated copper and simultaneously form a continuous copper film which eventually c
    Type: Application
    Filed: January 30, 2001
    Publication date: August 16, 2001
    Inventors: Kenji Nakamura, Masao Nakazawa
  • Patent number: 6261433
    Abstract: The invention provides an apparatus and a method for achieving reliable, consistent metal electroplating or electrochemical deposition onto semiconductor substrates. More particularly, the invention provides uniform and void-free deposition of metal onto metal seeded semiconductor substrates having sub-micron, high aspect ratio features. The invention provides an electrochemical deposition cell comprising a substrate holder, a cathode electrically contacting a substrate plating surface, an electrolyte container having an electrolyte inlet, an electrolyte outlet and an opening adapted to receive a substrate plating surface and an anode electrically connect to an electrolyte. Preferably, a vibrator is attached to the substrate holder to vibrate the substrate in at least one direction, and an auxiliary electrode is disposed adjacent the electrolyte outlet to provide uniform deposition across the substrate surface.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: July 17, 2001
    Assignee: Applied Materials, Inc.
    Inventor: Uziel Landau
  • Patent number: 6258239
    Abstract: In a process for manufacturing an electrode for a PEM fuel cell or an electrochemical energy converter, an ion-exchange polymer is applied to one face of an electrode substrate. An electrocatalyst is then applied to the substrate by electrochemical deposition, preferably from a solution containing one or more complexes or salts of the electrocatalyst. The electrochemical deposition occurs by application of a voltage between a pair of electrodes, one of which is the electrode under preparation. The voltage between the two electrodes is controlled by controlling the potential of the working electrode. A pulsed voltage profile is applied across the two electrodes during the electrodeposition process.
    Type: Grant
    Filed: December 14, 1998
    Date of Patent: July 10, 2001
    Assignee: Ballard Power Systems Inc.
    Inventors: Gabriele D. Stäb, Peter Urban
  • Patent number: 6245676
    Abstract: The flexibility of a wiring design is improved by preventing any erosion from happening upon forming a buried wiring. An interlayer insulating film is formed on a silicon substrate, and then trenches are formed in the interlayer insulating film. Thereafter, the barrier layer is deposited on side surfaces and a bottom surface in the trenches and on an entire area on the interlayer insulating film, and a copper seed layer is formed over an entire area on the barrier layer. Fountain plating is performed using the copper seed layer as an electrode to deposit the copper plated layer on the trenches and on a peripheral area of the same the copper plated layer buries the trenches and has a protruded configuration. Thereafter, the surface of the copper plated layer is polished with a CMP method until the interlayer insulating film is exposed to form a buried wiring.
    Type: Grant
    Filed: February 22, 1999
    Date of Patent: June 12, 2001
    Assignee: NEC Corporation
    Inventor: Kazuyoshi Ueno
  • Patent number: 6210555
    Abstract: A layer of a metal is electroplated onto an electrically conducting substrate having a generally smooth surface with a small recess therein, having a transverse dimension not greater than about 350 micrometers, typically from about 5 micrometers to about 350 micrometers, by immersing the substrate and a counterelectrode in an electroplating bath of the metal to be electroplated and passing a modulated reversing electric current between the electrodes. The current contains pulses that are cathodic with respect to said substrate and pulses that are anodic with respect to said substrate. The cathodic pulses have a duty cycle less than about 50% and said anodic pulses have a duty cycle greater than about 50%, the charge transfer ratio of the cathodic pulses to the anodic pulses is greater than one, and the frequency of said pulses ranges from about 10 Hertz to about 5000 Hertz.
    Type: Grant
    Filed: January 29, 1999
    Date of Patent: April 3, 2001
    Assignee: Faraday Technology Marketing Group, LLC
    Inventors: E. Jennings Taylor, Jenny J. Sun, Chengdong Zhou
  • Patent number: 6203684
    Abstract: A smooth layer of a metal is electroplated onto a microrough electrically conducting substrate by immersing the substrate and a counterelectrode in an electroplating bath of the metal to be electroplated and passing a modulated reversing electric current between the electrodes. The current contains pulses that are cathodic with respect to said substrate and pulses that are anodic with respect to said substrate. The cathodic pulses have a duty cycle less than about 50% and said anodic pulses have a duty cycle greater than about 50%, the charge transfer ratio of the cathodic pulses to the anodic pulses is greater than one, and the frequency of said pulses ranges from about 10 Hertz to about 5000 Hertz.
    Type: Grant
    Filed: October 14, 1998
    Date of Patent: March 20, 2001
    Assignee: Faraday Technology Marketing Group, LLC
    Inventors: E. Jennings Taylor, Chengdong Zhou, Jenny J. Sun
  • Patent number: 6165630
    Abstract: A method for applying a zinc layer onto an aluminum or aluminum alloy sheet, comprising pretreating the surface and applying the layer by electrolytic galvanizing, the pretreating comprises electrochemical graining of the surface, for example in a solution having a pH less than 3 with an alternating current applied between the sheet and an electrode. In an alternative method, the pretreating includes applying a preliminary zinc layer by immersing the surface in a zinc-containing alkaline solution, applying a potential to the sheet and reversing the polarity of said potential at least once. The sheets are useful for building cladding sheets and automotive panels.
    Type: Grant
    Filed: April 8, 1999
    Date of Patent: December 26, 2000
    Assignee: Corus Bausysteme GmbH
    Inventors: Horst Gehlhaar, Martinus Godefridus Johannes Spanjers, Joop Nicolaas Mooij, Wilhelmus Jacobus Van Der Meer
  • Patent number: 6132584
    Abstract: The invention relates to a method of generating short, cyclically repeating, unipolar or bipolar pulse currents I.sub.G, I.sub.E for electroplating, and to a circuit arrangement for electroplating with which pulse currents I.sub.G, I.sub.E can be generated. Electroplating methods of this type are referred to as pulse-plating methods. According to the invention, the secondary winding 6 of a current transformer 1 is connected in series into the electroplating direct current circuit 5, consisting of a bath direct current source 2 and a bath which is contained in an electroplating cell and which is represented by resistor R.sub.B. The primary winding 7 of the transformer has a larger number of turns than the secondary winding. The primary winding is controlled with pulses of high voltage and with relatively low current. The high pulse current on the secondary side temporarily compensates in pulses the electroplating direct current.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: October 17, 2000
    Assignee: Atotech Deutschland GmbH
    Inventor: Egon Hubel
  • Patent number: 6107186
    Abstract: Erosion of high density metallization areas associated with conventional damascene-CMP processing is avoided and greater planarity achieved by selectively increasing the metal overburden layer thickness at high density metallization regions. Embodiments include initially filling recesses formed in the substrate surface with a metal forming a blanket or overburden layer of the metal thereon. Regions of the blanket or overburden layer overlying regions of high density metallization are selectively electroplated to a greater thickness. The surface is then planarized by CMP, with the selectively increased thickness areas of the overburden layer compensating for greater erosion rates thereat during CMP, thereby resulting in greater planarity of the polished surface.
    Type: Grant
    Filed: January 27, 1999
    Date of Patent: August 22, 2000
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Darrell M. Erb
  • Patent number: 6099711
    Abstract: The invention relates to a method for the electrolytic deposition of metal coatings, in particular of copper coatings with certain physical-mechanical and optical properties and uniform coating thickness. According to known methods using soluble anodes and applying direct current, only uneven metal distribution can be attained on complex shaped workpieces. By using a pulse current or pulse voltage method, the problem of the coatings being of varying thickness at various places on the workpiece surfaces can indeed be reduced. However, the further problem of the geometric ratios being changed continuously during the depositing process by dissolving of the anodes is not resolved thus. This can be avoided by using insoluble anodes.
    Type: Grant
    Filed: April 23, 1998
    Date of Patent: August 8, 2000
    Assignee: Atotech Deutschland GmbH
    Inventors: Wolfgang Dahms, Heinrich Meyer, Stefan Kretschmer
  • Patent number: 6080504
    Abstract: A gas diffusion electrode for a proton exchange membrane fuel cell is prepared by electrodeposition of a catalytic metal in nanocrystalline form on a substrate by contacting an electrically conductive substrate and a counterelectrode with a plating bath containing ions of a metal to be deposited on the substrate and passing a pulsed electric current between the substrate and counterelectrode having pulses that are cathodic with respect to the substrate and have a short on-time and/or a short duty cycle with a frequency from about 10 hertz to about 5000 hertz. In a preferred embodiment the electric current is a modulated reversing electric current having pulses that are cathodic with respect to the substrate and pulses that are anodic with respect to the substrate, the cathodic pulses having a short on-time and/or short duty cycle, the charge transfer ratio of the cathodic pulses to the anodic pulses being greater than one, and the frequency of the pulses ranging from about 10 hertz to about 5 kilohertz.
    Type: Grant
    Filed: November 2, 1998
    Date of Patent: June 27, 2000
    Assignee: Faraday Technology, Inc.
    Inventors: E. Jennings Taylor, Maria E. Inman
  • Patent number: 6071398
    Abstract: The present invention relates to a method of electrodepositing metal onto a substrate, which comprises applying a pulsed periodic reverse current across the electrodes of a plating cell utilizing a peak reverse current density and peak forward current density; and varying the ratio of peak reverse current density to peak forward current density in periodic cycles to provide metal deposits of uniform thickness and appearance upon the substrate. The invention also relates to a process for improving the properties of an electrodeposit, particularly on substrates having uneven surfaces or apertures, by using programmed pulse periodic reverse current modulation. More particularly, it involves varying the anodic to cathodic current density ratio, in order to improve the surface uniformity appearance, grain structure and levelling of the deposit while maintaining high current density throwing power.
    Type: Grant
    Filed: October 6, 1997
    Date of Patent: June 6, 2000
    Assignee: Learonal, Inc.
    Inventors: James L. Martin, Stephane Menard, David N. Michelen
  • Patent number: 6036833
    Abstract: An electroplating method of forming platings of nickel, cobalt, nickel alloys or cobalt alloys with reduced stress in a Watts bath, a chloride bath or a combination thereof, by employing pulse plating with periodic reverse pulses and a sulfonated naphthalene additive. This method makes it possible to deposit nickel, cobalt, nickel alloy or cobalt alloy platings without internal stress.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: March 14, 2000
    Inventors: Peter Torben Tang, Henrik Dylmer, Per M.o slashed.ller
  • Patent number: 5972192
    Abstract: High aspect ratio openings in excess of 3, such as trenches, via holes or contact holes, in a dielectric layer are voidlessly filled employing a pulse or forward-reverse pulse electroplating technique to deposit copper or a copper-base alloy. A leveling agent is incorporated in the electroplating composition to ensure that the opening is filled substantially sequentially from the bottom upwardly.
    Type: Grant
    Filed: July 23, 1997
    Date of Patent: October 26, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Valery Dubin, Chiu Ting, Robin W. Cheung
  • Patent number: 5935407
    Abstract: A process is provided for producing an abrasive coating on a substrate surface by applying a bond coat by low pressure plasma spraying and anchoring to the bond coat abrasive particles by electroplating and embedding the particles into an oxidation resistant matrix by entrapment plating.
    Type: Grant
    Filed: November 6, 1997
    Date of Patent: August 10, 1999
    Assignee: Chromalloy Gas Turbine Corporation
    Inventors: Krassimir P. Nenov, Richard Fenton, Joseph A. Fuggini, Peter Howard
  • Patent number: 5911863
    Abstract: In a method of manufacturing foils of plastic material which are electrically conductive in a transverse direction, but not in the plane of the foil wherein micropassages are formed in the foil by etching nucleus traces which are generated by exposure to a heavy ion beam, conductive layers are deposited on one side of the foil and the micropassages are filled by electrolytic metal ion depositions from the other side until caps are formed on the passages. After dissolving the two conductive layers, the steps are repeated to form caps also on the passages at the other side of the foil so as to provide for good contacting capabilities at both sides of the foil.
    Type: Grant
    Filed: December 3, 1997
    Date of Patent: June 15, 1999
    Assignee: Gesellschaft fur Schwerionenforschung mbH
    Inventors: Johann Vetter, Dobri Dobrev, Norbert Angert
  • Patent number: 5804054
    Abstract: High quality thin films of copper-indium-gallium-diselenide useful in the production of solar cells are prepared by electrodepositing at least one of the constituent metals onto a glass/Mo substrate, followed by physical vapor deposition of copper and selenium or indium and selenium to adjust the final stoichiometry of the thin film to approximately Cu(In,Ga)Se.sub.2. Using an AC voltage of 1-100 KHz in combination with a DC voltage for electrodeposition improves the morphology and growth rate of the deposited thin film. An electrodeposition solution comprising at least in part an organic solvent may be used in conjunction with an increased cathodic potential to increase the gallium content of the electrodeposited thin film.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: September 8, 1998
    Assignee: Davis, Joseph & Negley
    Inventors: Raghu N. Bhattacharya, Miguel A. Contreras, James Keane, Andrew L. Tennant, John R. Tuttle, Kannan Ramanathan, Rommel Noufi
  • Patent number: 5792333
    Abstract: A method of surface-roughening a copper foil by subjecting at least one side of the copper foil to electro-plating using an alternating current, wherein a sulfuric acid bath or a sulfuric acid-copper sulfate bath is used as an electrolyte.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: August 11, 1998
    Assignee: Circuit Foil Japan Co., Ltd.
    Inventors: Ryoichi Oguro, Tadao Nakaoka, Kazuyuki Inoue, Kazuhiro Hoshino
  • Patent number: 5730852
    Abstract: High quality thin films of copper-indium-gallium-diselenide useful in the production of solar cells are prepared by electrodepositing at least one of the constituent metals onto a glass/Mo substrate, followed by physical vapor deposition of copper and selenium or indium and selenium to adjust the final stoichiometry of the thin film to approximately Cu(In,Ga)Se.sub.2. Using an AC voltage of 1-100 KHz in combination with a DC voltage for electrodeposition improves the morphology and growth rate of the deposited thin film. An electrodeposition solution comprising at least in part an organic solvent may be used in conjunction with an increased cathodic potential to increase the gallium content of the electrodeposited thin film.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: March 24, 1998
    Assignee: Davis, Joseph & Negley
    Inventors: Raghu N. Bhattacharya, Miguel A. Contreras, James Keane, Andrew L. Tennant, John R. Tuttle, Kannan Ramanathan, Rommel Noufi
  • Patent number: 5662788
    Abstract: A method for forming a metallization layer (30). A first layer (14) is formed outwardly from a semiconductor substrate (10). Contact vias (16) are formed through the first layer (14) to the semiconductor substrate (10). A second layer (20) is formed outwardly from the first layer (14). Portions of the second layer (20) are selectively removed such that the remaining portion of the second layer (20) defines the layout of the metallization layer (30) and the contact vias (16). The first and second layers (14) and (20) are electroplated by applying a bi-polar modulated voltage having a positive duty cycle and a negative duty cycle to the layers in a solution containing metal ions. The voltage and surface potentials are selected such that the metal ions are deposited on the remaining portions of the second layer (20). Further, metal ions deposited on the first layer (14) during a positive duty cycle are removed from the first layer (14) during a negative duty cycle.
    Type: Grant
    Filed: June 3, 1996
    Date of Patent: September 2, 1997
    Assignee: Micron Technology, Inc.
    Inventors: Gurtej Sandhu Sandhu, Chris Chang Yu
  • Patent number: 5624626
    Abstract: The present invention provides a method for treating a ceramic body to provide a wettable surface on the ceramic body. According to the present invention, a ceramic body is immersed in an alkaline hydroxide solution. The ceramic body is connected to form the anode and a suitable metal is connected to form the cathode of an electrolytic cell. A difference in electrical potential is imposed across the electrolytic cell which is sufficient to remove portions of the ceramic body to provide a pitted surface on the ceramic body which is wettable.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 29, 1997
    Inventors: Thomas J. Walz, Issak S. Rossovsky
  • Patent number: 5605615
    Abstract: A method and apparatus for plating metals which delivers a voltage pulse with the possibility of a widely varying current magnitude characteristic to a plating electrode and an object having a large electrical reactance in terms of a parallel resistance and capacitance in order to raise the voltage potential between the electrode and an object to a programmed plating voltage overpotential and underpotential. The programmed plating voltage overpotential determines how fast the electrochemical reaction is allowed to proceed in the diffusion layer, and the programmed voltage underpotential determines how quickly the electrochemical reaction of the diffusion layer will slow down.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: February 25, 1997
    Assignee: Motorola, Inc.
    Inventors: Peter G. Goolsby, Dan R. Ramirez, Lei P. Lai
  • Patent number: 5584983
    Abstract: A method for the production of metal foam with high specific surface area is disclosed. A foam material which may be either conductive or nonconductive is provided. If the material is nonconductive, an electrically conductive covering layer is formed. The electrically conductive foam material is then electrolytically coated with nickel from a nickel plating bath. The bath includes at least one unsaturated organic second class brightener in an amount effective to promote preferential growth of nickel onto the foam material such that the value of the growth ratio R, defined by the total of the growth of metal onto the foam material in the direction of the preferential growth divided by the total of the growth of metal in a direction perpendicular to the direction of the preferential growth, is greater than one. The nickel plating may be carried out using pulse current. The bath liquid may be flowed through the openings of the foam substrate in one or more directions during the deposition.
    Type: Grant
    Filed: March 3, 1995
    Date of Patent: December 17, 1996
    Assignee: Stork Screens, B.V.
    Inventor: Wilhelmus A. Pruyn
  • Patent number: 5578175
    Abstract: A process for manufacturing an iridium and palladium oxides-coated titanium electrode comprises preparing a titanium substrate having a surface, applying iridium and palladium to be formed on the surface of the titanium substrate, and heat-treating the iridium and palladium oxides-applied titanium substrate to obtain an iridium and palladium oxides-coated titanium electrode. This invention provides a process for obtaining a coated titanium electrode having therein a good adhesion between the coating material and the titanium electrode, and having an excellent electrochemical stability and a superior catalytic activity in an acidic environment.
    Type: Grant
    Filed: August 16, 1994
    Date of Patent: November 26, 1996
    Assignee: National Science Council
    Inventors: Kwang-Lung Lin, Ju-Tung Lee, Yuan-Po Lee
  • Patent number: 5575897
    Abstract: A soft-magnetic multilayer thin film produced by electroplating, wherein an anode-dissolution process is effected by intermittently applying a reverse d.c. bias current with respect to the plating-forward current. Involving the anode-dissolution process allows the formation of a re-dissolution effect layer differing in crystal structure from the plated film layer. A soft-magnetic multilayer thin film characterized by having a multilayer film structure which comprises a plated layer and a re-dissolution effect layer laminated to each other and which the plated layer is at least magnetically isolated. Further, a method of manufacturing a soft-magnetic multilayer thin film having a multilayer film structure magnetically isolated only through plating, which is offered by introducing the anode-dissolution process.
    Type: Grant
    Filed: October 24, 1995
    Date of Patent: November 19, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Nobuyuki Komura, Yuuji Omata
  • Patent number: 5550104
    Abstract: A method for making superconducting ceramic precursor films by electrodeposition. In the electrodeposition step, superconducting precursor metal ions are electrodeposited onto a working electrode by applying a combined direct current voltage upon which is superimposed an alternating current having a frequency of between about 5 to 100 KHz. The resulting electrodeposited film is particularly well suited for further oxidation/annealing to form a superconducting ceramic.
    Type: Grant
    Filed: September 9, 1994
    Date of Patent: August 27, 1996
    Assignee: Davis, Joseph & Negley
    Inventor: Raghu N. Bhattacharya
  • Patent number: 5527445
    Abstract: A process for repairing degraded sections of metal tubes, such as heat exchanger tubes, by in situ electroforming utilizes a probe containing an electrode. The probe is movable through the tube to the site of degradation and is sealed in place, thereby creating an electrochemical cell. Electrolyte flows from a reservoir through the cell and a structural layer of metal is deposited on the tube using a pulsed direct current and a duty cycle of 10-60%. The metal layer so formed possesses an ultrafine grain size preferably with a highly twinned microcrystalline structure giving the layer excellent mechanical properties.
    Type: Grant
    Filed: January 9, 1995
    Date of Patent: June 18, 1996
    Assignee: Ontario Hydro
    Inventors: Gino Palumbo, Philip C. Lichtenberger, Francisco Gonzalez, Alexander M. Brennenstuhl
  • Patent number: 5495979
    Abstract: Metal bonded carbon fiber-reinforced composites are disclosed in which the metal and the composite are strongly bound by (1) providing a matrix-depleted zone in the composite of sufficient depth to provide a binding site for the metal to be bonded and then (2) infiltrating the metal into the matrix-free zone to fill a substantial portion of the zone and also provide a surface layer of metal, thereby forming a strong bond between the composite and the metal. The invention also includes the metal-bound composite itself, as well as the provision of a coating over the metal for high-temperature performance or for joining to other such composites or to other substrates.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: March 5, 1996
    Assignees: Surmet Corporation, Castle Technology Corporation
    Inventors: Suri A. Sastri, J. Paul Pemsler, Richard A. Cooke, John K. Litchfield, Mark B. Smith
  • Patent number: 5494563
    Abstract: A magnetic thin film head having a laminated structure includes a non-magnetic substrate, a lower magnetic layer deposited on the non-magnetic substrate, a magnetic gap layer overlying the lower magnetic layer, at least two insulating layers overlying the magnetic gap layer, at least one electrically conductive layer interposed between the insulating layers, and an upper magnetic layer overlying the insulating layers. A magnetic core of the magnetic thin film head is made up of the upper and lower magnetic layers, at least one of which includes a plurality of magnetically soft layers plated with a metal alloy and a plurality of modified layers each interposed between two adjoining magnetically soft layers. The modified layers function to magnetostatically separate the magnetically soft layers. Each of the modified layers is made by introducing, during electroplating, an anodic dissolution process wherein a surface to be plated is temporarily used as an anode.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: February 27, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yuuji Omata, Tatsuo Mifune
  • Patent number: 5489488
    Abstract: A soft magnetic multilayer film is manufactured by an electroplating process using an electrolyte containing metal ions. The soft magnetic multilayer film includes soft magnetic layers composed of elements, and deteriorated-soft magnetic layers composed of the same elements and alternating with the soft magnetic layers. The soft magnetic layers are preferably different in composition from the deteriorated-soft magnetic layers. In addition, it is preferable that the metal ions contained in the electrolyte include at least two of Ni ion, Co ion, and Fe ion.
    Type: Grant
    Filed: December 2, 1993
    Date of Patent: February 6, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroki Asai, Yuuji Omata
  • Patent number: 5486280
    Abstract: A process and apparatus for the application of a control variable having a fractal structure to a body or process. The process of the present invention comprises the steps of generating a control variable having a fractal structure and applying the control variable to a body or process reacting in accordance with the control variable. The process is applicable to electroforming where first, second and successive pulsed-currents are applied to cause the deposition of material onto a substrate, such that the first pulsed-current, the second pulsed-current, and successive pulsed currents form a fractal pulsed-current waveform.
    Type: Grant
    Filed: October 20, 1994
    Date of Patent: January 23, 1996
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Jonathan S. Bullock, IV, Roger L. Lawson
  • Patent number: 5326454
    Abstract: A method is disclosed for the production of highly diffusive or absorptive metal surfaces. A dendritic crystal structure surface layer of metal is electrodeposited on a substrate, using a bipolar pulse plating technique. This metal surface layer may then be oxidized to provide a highly anti-reflective surface.
    Type: Grant
    Filed: February 28, 1992
    Date of Patent: July 5, 1994
    Assignee: Martin Marietta Corporation
    Inventor: Darell E. Engelhaupt
  • Patent number: 5275703
    Abstract: A method of adhering a colored electroplating layer on zinc-electroplated steel articles that utilizes an alternating current power supply which supplies electricity of frequency of 10-20 Hz, voltage of 60-120 V, and current density of 20-80 Amp/dM.sup.2 ; and an aqueous electroplating solution which contains 150-200 g/l of silicate, 15-20 g/l of sodium hydroxide and 5-50 g/l of cobalt salt. The electroplating liquid is kept at a constant temperature of 20.degree. C.-30.degree. C. In this method, two stages are utilized to perform the electroplating and adhere a colored electroplated layer so that the surface of the zinc-electroplated layer can adhere a blue electroplated layer. Thus the aesthetics and the corrosion-resistant capability of the zinc-electroplated layer can be enhanced because of the colored electroplated layer adhered to the surface of the zinc-electroplated layer.
    Type: Grant
    Filed: December 15, 1992
    Date of Patent: January 4, 1994
    Assignee: Taiwan Galvanizing Co., Ltd.
    Inventors: Han C. Shih, Gim R. Cheng, Mann Y. Wu
  • Patent number: 5273641
    Abstract: The invention provides an apparatus and method for determining levelling power of an electrolyte. An anode and cathode are immersed in the electrolyte. The cathode has a plating surface for electrodeposition of a metal from the electrolyte. The plating surface has a peak region and a base region separated and electrically isolated by an insulator. The peak region has a greater tendency to electrodeposit the metal per unit surface area than the base region. The anode and cathode are placed in a test cell or suspended in a commercial electrodeposition cell. A means for applying current between said anode and said cathode is used for causing the metal from the electrolyte to electrodeposit on the plating surface of the cathode. The current from plating on the peak region and the base region are measured separately to determine levelling power of an electrolyte.
    Type: Grant
    Filed: November 20, 1992
    Date of Patent: December 28, 1993
    Assignee: Inco Limited
    Inventors: Vladimir K. Blechta, Zheng Z. Wang, Dale W. Krueger
  • Patent number: 5270229
    Abstract: A thin film semiconductor device comprising a semiconductor layer and an electrically conductive thin film which are formed by an alternate current plating method, and a process for producing thereof.
    Type: Grant
    Filed: April 27, 1992
    Date of Patent: December 14, 1993
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Shin-ichiro Ishihara
  • Patent number: 5242535
    Abstract: A method of forming a copper circuit pattern on a ceramic substrate. In accordance with the method, first and second layers of copper oxide and copper are applied to the ceramic substrate. Selected regions of the copper are then masked so that unmasked regions are formed on the copper in a configuration of the copper circuit pattern. Masked regions are formed on the copper adjacent the unmasked regions, where copper cannot be plated. The unmasked regions of the copper are plated in a neutral pH solution by a reverse pulse plating process. The masking is then removed and the copper and copper oxide layers are etched so that the copper and copper oxide is removed from the unmasked regions. Thereafter, the remaining copper is direct bonded to the substrate.
    Type: Grant
    Filed: September 29, 1992
    Date of Patent: September 7, 1993
    Assignee: The BOC Group, Inc.
    Inventors: Satish S. Tamhaukar, Edward Chang, Richard Paciej, Mark J. Kirschner
  • Patent number: 5158653
    Abstract: A process for the production of a composition modulated alloy having a predetermined concentration is disclosed, in which alternating layers of at least two metals are successively deposited upon a substrate by electrodeposition, vacuum deposition, vapor deposition, or sputtering. The individual thicknesses of at least one metal's layers are varied in a predetermined manner. Pulsed galvanostatic electrodeposition using a tailored waveform is preferred. A copper-nickel concentration graded alloy is disclosed. Concentration graded alloys of predetermined concentration having at least one region of local homogeneity are also disclosed. The region of local homogeneity has a thickness corresponding to the thickness of two adjacent layers of different metals which have been diffusion annealed together. A pulsed electrodeposition/diffusion anneal process for production of such alloys is also disclosed.
    Type: Grant
    Filed: September 26, 1988
    Date of Patent: October 27, 1992
    Inventors: David S. Lashmore, Moshe P. Dariel
  • Patent number: 5141602
    Abstract: An apparatus and method for plating metal on a conductor and/or across gaps on insulating substrates is described incorporating two probes, a probe positioner, first circuitry for applying alternating-current electrical power wherein the magnitude of the voltage is controlled as a function of time, and second circuitry for applying alternating-current electrical power wherein the magnitude of the current is controlled as a function of time. The invention overcomes the problem of providing an automatic apparatus for reliably repairing defective wiring or completing seeded sections of wiring having a wide range of initial thermal and electrical characteristics.
    Type: Grant
    Filed: June 18, 1991
    Date of Patent: August 25, 1992
    Assignee: International Business Machines Corporation
    Inventors: Chengjun J. Chen, Richard I. Kaufman, Julian P. Partridge
  • Patent number: 5087333
    Abstract: Apparatus for plating electrical or electronic components, comprises a plating chamber (2) for receiving electrolyte through which a current is to be passed via a first anode (10) and cathode (13) pair, means being provided to arrange a component (12) to be plated as the cathode of said first pair, means for supplying the plating chamber with electrolyte enriched with plating material, the supplying means including a reservoir chamber (4) for receiving electrolyte through which a current is to be passed via a second anode and cathode pair (21, 22), means being provided to arrange a body of plating material (17) as the anode of said second pair, whereby in use plating material dissolved from the anode of the second pair enriches the electrolyte supplied to the plating chamber (2) and is deposited on the cathode of the first pair.
    Type: Grant
    Filed: May 16, 1990
    Date of Patent: February 11, 1992
    Assignee: Sun Industrial Coatings Private Limited
    Inventor: Ah T. Sim