Patents by Inventor Thomas A. Ponnuswamy

Thomas A. Ponnuswamy 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).

  • Publication number: 20230298894
    Abstract: In one example, an electroplating system comprises a bath reservoir, an anode in the bath reservoir, and a direct-current power supply. The bath reservoir initially contains a first-electrolyte solution that includes an alkaline copper-complexed solution. The bath reservoir is arranged to be drained of the first-electrolyte solution and replaced with and contain a second-electrolyte solution. The second-electrolyte solution includes an acidic-copper plating solution. The direct-current power supply generates a first direct current between the clamp and the anode to electroplate a first copper layer on the cobalt layer of the substrate submerged in the first-electrolyte solution. The direct-current power supply then generates a second direct current between the clamp and the anode to electroplate a second copper layer on the first copper layer of the substrate submerged in the second electrolyte solution. Other systems and methods are also described.
    Type: Application
    Filed: May 25, 2023
    Publication date: September 21, 2023
    Inventors: Jeyavel Velmurugan, Bryan L. Buckalew, Thomas A. Ponnuswamy
  • Patent number: 11699590
    Abstract: In one example, an electroplating system comprises a first bath reservoir, a second bath reservoir, a clamp, a first anode in the first bath reservoir, a second anode in the second bath reservoir, and a direct current power supply. The first bath reservoir contains a first electrolyte solution that includes an alkaline copper-complexed solution. The second bath reservoir contains a second electrolyte solution that includes an acidic copper plating solution. The direct current power supply generates a first direct current between the clamp and the first anode to electroplate a first copper layer on the cobalt layer of the wafer submerged in the first electrolyte solution. The direct current power supply then generates a second direct current between the clamp and the second anode to electroplate a second copper layer on the first copper layer of the wafer submerged in the second electrolyte solution.
    Type: Grant
    Filed: January 26, 2021
    Date of Patent: July 11, 2023
    Assignee: Lam Research Corporation
    Inventors: Jeyavel Velmurugan, Bryan L. Buckalew, Thomas A. Ponnuswamy
  • Patent number: 11542630
    Abstract: Provided are cleaning methods and systems to remove unintended metallic deposits from electroplating apparatuses using reverse current deplating techniques. Such cleaning involves positioning a cleaning (deplating) disk in an electroplating cup similar to a regular processed substrate. The front surface of the cleaning disk includes a corrosion resistant conductive material to form electrical connections to deposits on the cup's surfaces. The disk is sealed in the cup and submerged into a plating solution. A reverse current is then applied to the front conductive surface of the disk to initiate deplating of the deposits. Sealing compression in the cup may change during cleaning to cause different deformation of the lip seal and to form new electrical connections to the deposits. The proposed cleaning may be applied to remove deposits formed during electroplating of alloys, in particular, tin-silver alloys widely used for semiconductor and wafer level packaging.
    Type: Grant
    Filed: December 16, 2019
    Date of Patent: January 3, 2023
    Assignee: Novellus Systems, Inc.
    Inventors: Lee Peng Chua, Steven T. Mayer, Thomas A. Ponnuswamy, Santosh Kumar
  • Publication number: 20220216104
    Abstract: Systems and methods are provided for method for etch assisted gold (Au) through silicon mask plating (EAG-TSM). An example method comprises providing a seed layer on a substrate and providing a silicon mask on at least a portion of the seed layer on the substrate. The silicon mask includes one or more via to be filled with Au. The masked substrate is subjected to at least one processing cycle, each processing cycle including an Au plating sub-step and an etch treatment sub-step. The cycles are repeated until a selected via fill thickness is achieved.
    Type: Application
    Filed: February 13, 2020
    Publication date: July 7, 2022
    Inventors: Lee Peng Chua, Defu Liang, Jacob Kurtis Blickensderfer, Thomas A. Ponnuswamy, Bryan L. Buckalew, Steven T. Mayer
  • Patent number: 11168407
    Abstract: In one example, an electroplating system comprises a bath reservoir, a holding device, an anode, a direct current power supply, and a controller. The bath reservoir contains an electrolyte solution. The holding device holds a wafer submerged in the electrolyte solution. The wafer comprises features covered by a cobalt layer. The anode is opposite to the wafer and submerged in the electrolyte solution. The direct current power supply generates a direct current between the holding device and the anode. A combination of forward and reverse pulses is applied between the holding device and the anode to electroplate a copper layer on the cobalt layer of the wafer.
    Type: Grant
    Filed: February 6, 2020
    Date of Patent: November 9, 2021
    Assignee: Lam Research Comporation
    Inventors: Jeyavel Velmurugan, Bryan L. Buckalew, Thomas A. Ponnuswamy
  • Publication number: 20210151322
    Abstract: In one example, an electroplating system comprises a first bath reservoir, a second bath reservoir, a clamp, a first anode in the first bath reservoir, a second anode in the second bath reservoir, and a direct current power supply. The first bath reservoir contains a first electrolyte solution that includes an alkaline copper-complexed solution. The second bath reservoir contains a second electrolyte solution that includes an acidic copper plating solution. The direct current power supply generates a first direct current between the clamp and the first anode to electroplate a first copper layer on the cobalt layer of the wafer submerged in the first electrolyte solution. The direct current power supply then generates a second direct current between the clamp and the second anode to electroplate a second copper layer on the first copper layer of the wafer submerged in the second electrolyte solution.
    Type: Application
    Filed: January 26, 2021
    Publication date: May 20, 2021
    Inventors: Jeyavel Velmurugan, Bryan L. Buckalew, Thomas A. Ponnuswamy
  • Patent number: 10954605
    Abstract: An apparatus for continuous simultaneous electroplating of two metals having substantially different standard electrodeposition potentials (e.g., for deposition of Sn—Ag alloys) comprises an anode chamber for containing an anolyte comprising ions of a first, less noble metal, (e.g., tin), but not of a second, more noble, metal (e.g., silver) and an active anode; a cathode chamber for containing catholyte including ions of a first metal (e.g., tin), ions of a second, more noble, metal (e.g., silver), and the substrate; a separation structure positioned between the anode chamber and the cathode chamber, where the separation structure substantially prevents transfer of more noble metal from catholyte to the anolyte; and fluidic features and an associated controller coupled to the apparatus and configured to perform continuous electroplating, while maintaining substantially constant concentrations of plating bath components for extended periods of use.
    Type: Grant
    Filed: September 5, 2018
    Date of Patent: March 23, 2021
    Assignee: Novellus Systems, Inc.
    Inventors: Lee Peng Chua, Steven T. Mayer, David W. Porter, Thomas A. Ponnuswamy
  • Patent number: 10930511
    Abstract: In one example, an electroplating system comprises a first bath reservoir, a second bath reservoir, a clamp, a first anode in the first bath reservoir, a second anode in the second bath reservoir, and a direct current power supply. The first bath reservoir contains a first electrolyte solution that includes an alkaline copper-complexed solution. The second bath reservoir contains a second electrolyte solution that includes an acidic copper plating solution. The direct current power supply generates a first direct current between the clamp and the first anode to electroplate a first copper layer on the cobalt layer of the wafer submerged in the first electrolyte solution. The direct current power supply then generates a second direct current between the clamp and the second anode to electroplate a second copper layer on the first copper layer of the wafer submerged in the second electrolyte solution.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: February 23, 2021
    Assignee: Lam Research Corporation
    Inventors: Jeyavel Velmurugan, Bryan Buckalew, Thomas Ponnuswamy
  • Publication number: 20200255964
    Abstract: In one example, an electroplating system comprises a bath reservoir, a holding device, an anode, a direct current power supply, and a controller. The bath reservoir contains an electrolyte solution. The holding device holds a wafer submerged in the electrolyte solution. The wafer comprises features covered by a cobalt layer. The anode is opposite to the wafer and submerged in the electrolyte solution. The direct current power supply generates a direct current between the holding device and the anode. A combination of forward and reverse pulses is applied between the holding device and the anode to electroplate a copper layer on the cobalt layer of the wafer.
    Type: Application
    Filed: February 6, 2020
    Publication date: August 13, 2020
    Inventors: Jeyavel Velmurugan, Bryan L. Buckalew, Thomas A. Ponnuswamy
  • Patent number: 10714436
    Abstract: Systems and methods for achieving uniformity across a redistribution layer are described. One of the methods includes patterning a photoresist layer over a substrate. The patterning defines a region for a conductive line and a via disposed below the region for the conductive line. The method further includes depositing a conductive material in between the patterned photoresist layer, such that the conductive material fills the via and the region for the conductive line. The depositing causes an overgrowth of conductive material of the conductive line to form a bump of the conductive material over the via. The method also includes planarizing a top surface of the conductive line while maintaining the patterned photoresist layer present over the substrate. The planarizing is facilitated by exerting a horizontal shear force over the conductive line and the bump. The planarizing is performed to flatten the bump.
    Type: Grant
    Filed: March 14, 2017
    Date of Patent: July 14, 2020
    Assignee: Lam Research Corporation
    Inventors: Bryan L. Buckalew, Thomas A. Ponnuswamy, Steven T. Mayer, Stephen J. Banik, II, Justin Oberst
  • Patent number: 10662545
    Abstract: Methods and apparatus for electroplating material onto a substrate are provided. In many cases the material is metal and the substrate is a semiconductor wafer, though the embodiments are no so limited. Typically, the embodiments herein utilize a porous ionically resistive plate positioned near the substrate, the plate having a plurality of interconnecting 3D channels and creating a cross flow manifold defined on the bottom by the plate, on the top by the substrate, and on the sides by a cross flow confinement ring. During plating, fluid enters the cross flow manifold both upward through channels in the plate, and laterally through a cross flow side inlet positioned on one side of the cross flow confinement ring. The flow paths combine in the cross flow manifold and exit at the cross flow exit, which is positioned opposite the cross flow inlet. These combined flow paths result in improved plating uniformity.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: May 26, 2020
    Assignee: Novellus Systems, Inc.
    Inventors: Steven T. Mayer, Bryan L. Buckalew, Haiying Fu, Thomas Ponnuswamy, Hilton Diaz Camilo, Robert Rash, David W. Porter
  • Patent number: 10648097
    Abstract: In one example, an electroplating system comprises a bath reservoir, a holding device, an anode, a direct current power supply, and a controller. The bath reservoir contains an electrolyte solution. The holding device holds a wafer submerged in the electrolyte solution. The wafer comprises features covered by a cobalt layer. The anode is opposite to the wafer and submerged in the electrolyte solution. The direct current power supply generates a direct current between the holding device and the anode. A combination of forward and reverse pulses is applied between the holding device and the anode to electroplate a copper layer on the cobalt layer of the wafer.
    Type: Grant
    Filed: March 30, 2018
    Date of Patent: May 12, 2020
    Assignee: Lam Research Corporation
    Inventors: Jeyavel Velmurugan, Bryan L. Buckalew, Thomas A. Ponnuswamy
  • Publication number: 20200115816
    Abstract: Provided are cleaning methods and systems to remove unintended metallic deposits from electroplating apparatuses using reverse current deplating techniques. Such cleaning involves positioning a cleaning (deplating) disk in an electroplating cup similar to a regular processed substrate. The front surface of the cleaning disk includes a corrosion resistant conductive material to form electrical connections to deposits on the cup's surfaces. The disk is sealed in the cup and submerged into a plating solution. A reverse current is then applied to the front conductive surface of the disk to initiate deplating of the deposits. Sealing compression in the cup may change during cleaning to cause different deformation of the lip seal and to form new electrical connections to the deposits. The proposed cleaning may be applied to remove deposits formed during electroplating of alloys, in particular, tin-silver alloys widely used for semiconductor and wafer level packaging.
    Type: Application
    Filed: December 16, 2019
    Publication date: April 16, 2020
    Inventors: Lee Peng Chua, Steven T. Mayer, Thomas A. Ponnuswamy, Santosh Kumar
  • Patent number: 10538855
    Abstract: Provided are cleaning methods and systems to remove unintended metallic deposits from electroplating apparatuses using reverse current deplating techniques. Such cleaning involves positioning a cleaning (deplating) disk in an electroplating cup similar to a regular processed substrate. The front surface of the cleaning disk includes a corrosion resistant conductive material to form electrical connections to deposits on the cup's surfaces. The disk is sealed in the cup and submerged into a plating solution. A reverse current is then applied to the front conductive surface of the disk to initiate deplating of the deposits. Sealing compression in the cup may change during cleaning to cause different deformation of the lip seal and to form new electrical connections to the deposits. The proposed cleaning may be applied to remove deposits formed during electroplating of alloys, in particular, tin-silver alloys widely used for semiconductor and wafer level packaging.
    Type: Grant
    Filed: September 26, 2016
    Date of Patent: January 21, 2020
    Assignee: Novellus Systems, Inc.
    Inventors: Lee Peng Chua, Steven T. Mayer, Thomas A. Ponnuswamy, Santosh Kumar
  • Publication number: 20190301040
    Abstract: In one example, an electroplating system comprises a bath reservoir, a holding device, an anode, a direct current power supply, and a controller. The bath reservoir contains an electrolyte solution. The holding device holds a wafer submerged in the electrolyte solution. The wafer comprises features covered by a cobalt layer. The anode is opposite to the wafer and submerged in the electrolyte solution. The direct current power supply generates a direct current between the holding device and the anode. A combination of forward and reverse pulses is applied between the holding device and the anode to electroplate a copper layer on the cobalt layer of the wafer.
    Type: Application
    Filed: March 30, 2018
    Publication date: October 3, 2019
    Inventors: Jeyavel Velmurugan, Bryan Buckalew, Thomas Ponnuswamy
  • Publication number: 20190304789
    Abstract: In one example, an electroplating system comprises a first bath reservoir, a second bath reservoir, a clamp, a first anode in the first bath reservoir, a second anode in the second bath reservoir, and a direct current power supply. The first bath reservoir contains a first electrolyte solution that includes an alkaline copper-complexed solution. The second bath reservoir contains a second electrolyte solution that includes an acidic copper plating solution. The direct current power supply generates a first direct current between the clamp and the first anode to electroplate a first copper layer on the cobalt layer of the wafer submerged in the first electrolyte solution. The direct current power supply then generates a second direct current between the clamp and the second anode to electroplate a second copper layer on the first copper layer of the wafer submerged in the second electrolyte solution.
    Type: Application
    Filed: March 30, 2018
    Publication date: October 3, 2019
    Inventors: Jeyavel Velmurugan, Bryan Buckalew, Thomas Ponnuswamy
  • Patent number: 10301738
    Abstract: Disclosed are pre-wetting apparatus designs and methods. In some embodiments, a pre-wetting apparatus includes a degasser, a process chamber, and a controller. The process chamber includes a wafer holder configured to hold a wafer substrate, a vacuum port configured to allow formation of a subatmospheric pressure in the process chamber, and a fluid inlet coupled to the degasser and configured to deliver a degassed pre-wetting fluid onto the wafer substrate at a velocity of at least about 7 meters per second whereby particles on the wafer substrate are dislodged and at a flow rate whereby dislodged particles are removed from the wafer substrate. The controller includes program instructions for forming a wetting layer on the wafer substrate in the process chamber by contacting the wafer substrate with the degassed pre-wetting fluid admitted through the fluid inlet at a flow rate of at least about 0.4 liters per minute.
    Type: Grant
    Filed: October 3, 2017
    Date of Patent: May 28, 2019
    Assignee: Novellus Systems, Inc.
    Inventors: Bryan L. Buckalew, Steven T. Mayer, Thomas A. Ponnuswamy, Robert Rash, Brian Paul Blackman, Doug Higley
  • Patent number: 10211052
    Abstract: Systems and methods for fabrication of a redistribution layer are described. There is no deposition of a seed layer, made from copper, on top of a substrate. The lack of the seed layer avoids a need for etching the seed layer. When the seed layer is not etched, the redistribution layer, also made from copper, is not etched.
    Type: Grant
    Filed: September 22, 2017
    Date of Patent: February 19, 2019
    Assignee: Lam Research Corporation
    Inventors: Bryan L. Buckalew, Stephen J. Banik, II, Joseph Richardson, Thomas A. Ponnuswamy
  • Patent number: 10190232
    Abstract: Disclosed herein are electroplating systems for electroplating nickel onto a semiconductor substrate having an electroplating cell for holding an electrolyte solution during electroplating which includes a cathode chamber and an anode chamber configured to hold a nickel anode, and having an oxygen removal device arranged to reduce oxygen concentration in the electrolyte solution as it is flowed to the anode chamber during electroplating and during idle times when the system is not electroplating. Also disclosed herein are methods of electroplating nickel onto a substrate in an electroplating cell having anode and cathode chambers, which include reducing the oxygen concentration in an electrolyte solution, flowing the electrolyte solution into the anode chamber and contacting a nickel anode therein, and electroplating nickel from the electrolyte solution onto a substrate in the cathode chamber, wherein the electrolyte solution in the cathode chamber is maintained at a pH of between about 3.5 and 4.5.
    Type: Grant
    Filed: August 6, 2013
    Date of Patent: January 29, 2019
    Assignee: Lam Research Corporation
    Inventors: Bryan L. Buckalew, Thomas A. Ponnuswamy, Ben Foley, Steven T. Mayer
  • Publication number: 20180371637
    Abstract: An apparatus for continuous simultaneous electroplating of two metals having substantially different standard electrodeposition potentials (e.g., for deposition of Sn—Ag alloys) comprises an anode chamber for containing an anolyte comprising ions of a first, less noble metal, (e.g., tin), but not of a second, more noble, metal (e.g., silver) and an active anode; a cathode chamber for containing catholyte including ions of a first metal (e.g., tin), ions of a second, more noble, metal (e.g., silver), and the substrate; a separation structure positioned between the anode chamber and the cathode chamber, where the separation structure substantially prevents transfer of more noble metal from catholyte to the anolyte; and fluidic features and an associated controller coupled to the apparatus and configured to perform continuous electroplating, while maintaining substantially constant concentrations of plating bath components for extended periods of use.
    Type: Application
    Filed: September 5, 2018
    Publication date: December 27, 2018
    Inventors: Lee Peng Chua, Steven T. Mayer, David W. Porter, Thomas A. Ponnuswamy