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).
-
Patent number: 9359688Abstract: Disclosed are methods of electroplating a metal onto a substrate surface in an electroplating bath and adjusting the pH of the bath. The methods may include exposing the substrate surface, a counter-electrode, and an acid generating surface to the bath, biasing the substrate surface sufficiently negative relative to the counterelectrode such that metal ions from the bath are reduced and plated onto the substrate surface, and biasing the acid generating surface sufficiently positive relative to the counterelectrode such that free hydrogen ions are generated at the acid generating surface thereby decreasing the pH of the bath. Also disclosed are apparatuses for electroplating metal onto a substrate surface in an electroplating bath, and for adjusting the pH of the electroplating bath. The apparatuses may include an acid generating surface configured to generate free hydrogen ions in the bath upon supply of sufficient positive voltage bias relative to a counterelectrode electrical contact.Type: GrantFiled: December 5, 2012Date of Patent: June 7, 2016Assignee: Novellus Systems, Inc.Inventors: Lee Peng Chua, Thomas A. Ponnuswamy, Mark Rea, Steven T. Mayer
-
Publication number: 20160145761Abstract: Disclosed herein are cleaning discs for cleaning one or more elements of a semiconductor processing apparatus. In some embodiments, the disc may have a substantially circular upper surface, a substantially circular lower surface, a substantially circular edge joining the upper and lower surfaces, and a plurality of pores opening at the edge and having an interior extending into the interior of the disc. In some embodiments, the pores are dimensioned such that a cleaning agent may be retained in the interior of the pores by an adhesive force between the cleaning agent and the interior surface of the pores. Also disclosed herein are cleaning methods involving loading a cleaning agent into a plurality of pores of a cleaning disc, positioning the cleaning disc within a semiconductor processing apparatus, and releasing cleaning agent from the plurality of pores such that elements of the apparatus are contacted by the released cleaning agent.Type: ApplicationFiled: November 23, 2015Publication date: May 26, 2016Inventors: Steven T. Mayer, Thomas A. Ponnuswamy, Lee Peng Chua, Robert Rash
-
Patent number: 9221081Abstract: Disclosed herein are cleaning discs for cleaning one or more elements of a semiconductor processing apparatus. In some embodiments, the disc may have a substantially circular upper surface, a substantially circular lower surface, a substantially circular edge joining the upper and lower surfaces, and a plurality of pores opening at the edge and having an interior extending into the interior of the disc. In some embodiments, the pores are dimensioned such that a cleaning agent may be retained in the interior of the pores by an adhesive force between the cleaning agent and the interior surface of the pores. Also disclosed herein are cleaning methods involving loading a cleaning agent into a plurality of pores of a cleaning disc, positioning the cleaning disc within a semiconductor processing apparatus, and releasing cleaning agent from the plurality of pores such that elements of the apparatus are contacted by the released cleaning agent.Type: GrantFiled: July 31, 2012Date of Patent: December 29, 2015Assignee: Novellus Systems, Inc.Inventors: Steven T. Mayer, Thomas A. Ponnuswamy, Lee Peng Chua, Robert Rash
-
Publication number: 20150041327Abstract: 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: ApplicationFiled: August 6, 2013Publication date: February 12, 2015Inventors: Bryan L. Buckalew, Thomas A. Ponnuswamy, Ben Foley, Steven T. Mayer
-
Publication number: 20140357089Abstract: The embodiments disclosed herein pertain to novel methods and apparatus for removing material from a substrate. In certain embodiments, the method and apparatus are used to remove negative photoresist, though the disclosed techniques may be implemented to remove a variety of materials. In practicing the disclosed embodiments, a stripping solution may be introduced from an inlet to an internal manifold, sometimes referred to as a cross flow manifold. The solution flows laterally through a relatively narrow cavity between the substrate and the base plate. Fluid exits the narrow cavity at an outlet, which is positioned on the other side of the substrate, opposite the inlet and internal manifold. The substrate spins while in contact with the stripping solution to achieve a more uniform flow over the face of the substrate. In some embodiments, the base plate includes protuberances which operate to increase the flow rate (and thereby increase the local Re) near the face of the substrate.Type: ApplicationFiled: May 29, 2013Publication date: December 4, 2014Applicant: Novellus Systems, Inc.Inventors: Bryan L. BUCKALEW, Steven T. MAYER, David PORTER, Thomas A. PONNUSWAMY
-
Publication number: 20140197037Abstract: A method of treating a copper containing structure on a substrate is disclosed. The method includes electrodepositing the copper containing structure on a substrate, annealing the copper containing structure, and forming an interface between a pad of the copper containing structure and a solder structure after anneal. The interface can have improved resistance to interfacial voiding. The copper containing structure is configured to deliver current between one or more ports and one or more solder structures in the integrated circuit package. Annealing the copper containing structure can move impurities and vacancies to the surface of the copper containing structure for subsequent removal.Type: ApplicationFiled: January 17, 2013Publication date: July 17, 2014Inventors: Bryan L. Buckalew, Steven T. Mayer, Thomas Ponnuswamy, David Porter
-
Publication number: 20140183049Abstract: The embodiments herein relate to methods and apparatus for electroplating one or more materials onto a substrate. In many cases the material is a metal and the substrate is a semiconductor wafer, though the embodiments are no so limited. Typically, the embodiments herein utilize a channeled plate positioned near the substrate, creating a cross flow manifold defined on the bottom by the channeled 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 the channels in the channeled 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: ApplicationFiled: December 11, 2013Publication date: July 3, 2014Applicant: Novellus Systems, Inc.Inventors: Steven T. Mayer, Bryan L. Buckalew, Haiying Fu, Thomas Ponnuswamy, Hilton Diaz Camilo, Robert Rash, David W. Porter
-
Patent number: 8703615Abstract: Disclosed are methods of depositing and annealing a copper seed layer. A copper seed layer may be deposited on a ruthenium layer disposed on a surface of a wafer and on features in the wafer. The thickness of the ruthenium layer may be about 40 Angstroms or less. The copper seed layer may be annealed in a reducing atmosphere having an oxygen concentration of about 2 parts per million or less. Annealing the copper seed layer in a low-oxygen atmosphere may improve the properties of the copper seed layer.Type: GrantFiled: February 7, 2012Date of Patent: April 22, 2014Assignee: Novellus Systems, Inc.Inventors: Thomas A. Ponnuswamy, John H. Sukamto, Jonathan D. Reid, Steven T. Mayer, Huanfeng Zhu
-
Publication number: 20130334052Abstract: 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: ApplicationFiled: May 24, 2013Publication date: December 19, 2013Inventors: Lee Peng Chua, Steven T. Mayer, David W. Porter, Thomas A. Ponnuswamy
-
Publication number: 20130292254Abstract: Disclosed herein are methods of cleaning a lipseal and/or cup bottom of an electroplating device by removing metal deposits accumulated in prior electroplating operations. The methods may include orienting a nozzle such that it is pointed substantially at the inner circular edge of the lipseal and/or cup bottom, and dispensing a stream of cleaning solution from the nozzle such that the stream contacts the inner circular edge of the lipseal and/or cup bottom while they are being rotated, removing metal deposits. In some embodiments, the stream has a velocity component against the rotational direction of the lipseal and/or cup bottom. In some embodiments, the deposits may include a tin/silver alloy. Also disclosed herein are cleaning apparatuses for mounting in electroplating devices and for removing electroplated metal deposits from their lipseals and/or cup bottoms. In some embodiments, the cleaning apparatuses may include a jet nozzle.Type: ApplicationFiled: March 28, 2013Publication date: November 7, 2013Inventors: Santosh Kumar, Bryan L. Buckalew, Steven T. Mayer, Thomas Ponnuswamy, Chad Michael Hosack, Robert Rash, Lee Peng Chua, David Porter
-
Publication number: 20130256146Abstract: 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: ApplicationFiled: March 29, 2013Publication date: October 3, 2013Inventors: Lee Peng Chua, Steven T. Mayer, Thomas A. Ponnuswamy, Santosh Kumar
-
Patent number: 8513124Abstract: Disclosed are methods of depositing a copper seed layer to be used for subsequent electroplating a bulk-layer of copper thereon. A copper seed layer may be deposited with different processes, including CVD, PVD, and electroplating. With electroplating methods for depositing a copper seed layer, disclosed are methods for depositing a copper alloy seed layer, methods for depositing a copper seed layer on the semi-noble metal layer with a non-corrosive electrolyte, methods of treating the semi-noble metal layer that the copper seed layer is deposited on, and methods for promoting a more uniform copper seed layer deposition across a semiconductor wafer.Type: GrantFiled: May 21, 2010Date of Patent: August 20, 2013Assignee: Novellus Systems, Inc.Inventors: Thomas A. Ponnuswamy, John H. Sukamto, Jonathan D. Reid, Steven T. Mayer
-
Patent number: 8500983Abstract: A plating protocol is employed to control plating of metal onto a wafer comprising a conductive seed layer. Initially, the protocol employs cathodic protection as the wafer is immersed in the plating solution. In certain embodiments, the current density of the wafer is constant during immersion. In a specific example, potentiostatic control is employed to produce a current density in the range of about 1.5 to 20 mA/cm2. The immersion step is followed by a high current pulse step. During bottom up fill inside the features of the wafer, a constant current or a current with a micropulse may be used. This protocol may protect the seed from corrosion while enhancing nucleation during the initial stages of plating.Type: GrantFiled: May 24, 2010Date of Patent: August 6, 2013Assignee: Novellus Systems, Inc.Inventors: Thomas A. Ponnuswamy, Bryan Pennington, Clifford Berry, Bryan L. Buckalew, Steven T. Mayer
-
Publication number: 20130171833Abstract: 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: ApplicationFiled: February 25, 2013Publication date: July 4, 2013Inventors: Bryan L. BUCKALEW, Steven T. MAYER, Thomas A. PONNUSWAMY, Robert RASH, Brian BLACKMAN, Doug HIGLEY
-
Patent number: 8308931Abstract: An apparatus for electroplating a layer of metal on the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer (preferably within 5 mm of the wafer surface) which serves to modulate ionic current at the wafer surface, and a second cathode configured to divert a portion of current from the wafer surface. The ionically resistive ionically permeable element in a preferred embodiment is a disk made of a resistive material having a plurality of perforations formed therein, such that perforations do not form communicating channels within the body of the disk. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.Type: GrantFiled: November 7, 2008Date of Patent: November 13, 2012Assignee: Novellus Systems, Inc.Inventors: Jonathan Reid, Bryan Buckalew, Zhian He, Seyang Park, Seshasayee Varadarajan, Bryan Pennington, Thomas Ponnuswamy, Patrick Breling, Glenn Ibarreta, Steven Mayer
-
Patent number: 8076241Abstract: Methods are provided for multi-step Cu metal plating on a continuous Ru metal film in recessed features found in advanced integrated circuits. The use of a continuous Ru metal film prevents formation of undesirable micro-voids during Cu metal filling of high-aspect-ratio recessed features, such as trenches and vias, and enables formation of large Cu metal grains that include a continuous Cu metal layer plated onto the continuous Ru metal film. The large Cu grains lower the electrical resistivity of the Cu filled recessed features and increase the reliability of the integrated circuit.Type: GrantFiled: September 30, 2009Date of Patent: December 13, 2011Assignees: Tokyo Electron Limited, Novellus Systems, Inc.Inventors: Frank M. Cerio, Jr., Shigeru Mizuno, Jonathan Reid, Thomas Ponnuswamy
-
Patent number: 7964506Abstract: A two-step semiconductor electroplating process deposits copper onto wafers coated with a semi-noble metal in manner that is uniform across the wafer and free of voids after a post electrofill anneal. A seed-layer plating bath nucleates copper uniformly and conformably at a high density in a very thin film using a unique pulsed waveform. The wafer is then annealed before a second bath fills the features. The seed-layer anneal improves adhesion and stability of the semi-noble to copper interface, and the resulting copper interconnect stays void-free after a post electrofill anneal.Type: GrantFiled: March 6, 2008Date of Patent: June 21, 2011Assignee: Novellus Systems, Inc.Inventors: Thomas Ponnuswamy, John Sukamto, Jonathan Reid, Steve Mayer
-
Publication number: 20110076390Abstract: Methods are provided for multi-step Cu metal plating on a continuous Ru metal film in recessed features found in advanced integrated circuits. The use of a continuous Ru metal film prevents formation of undesirable micro-voids during Cu metal filling of high-aspect-ratio recessed features, such as trenches and vias, and enables formation of large Cu metal grains that include a continuous Cu metal layer plated onto the continuous Ru metal film. The large Cu grains lower the electrical resistivity of the Cu filled recessed features and increase the reliability of the integrated circuit.Type: ApplicationFiled: September 30, 2009Publication date: March 31, 2011Applicants: TOKYO ELECTRON LIMITED, NOVELLUS SYSTEMS, INC.Inventors: Frank M. Cerio, JR., Shigeru Mizuno, Jonathan Reid, Thomas Ponnuswamy
-
Publication number: 20100300888Abstract: A plating protocol is employed to control plating of metal onto a wafer comprising a conductive seed layer. Initially, the protocol employs cathodic protection as the wafer is immersed in the plating solution. In certain embodiments, the current density of the wafer is constant during immersion. In a specific example, potentiostatic control is employed to produce a current density in the range of about 1.5 to 20 mA/cm2. The immersion step is followed by a high current pulse step. During bottom up fill inside the features of the wafer, a constant current or a current with a micropulse may be used. This protocol may protect the seed from corrosion while enhancing nucleation during the initial stages of plating.Type: ApplicationFiled: May 24, 2010Publication date: December 2, 2010Inventors: Thomas A. Ponnuswamy, Bryan Pennington, Clifford Berry, Bryan L. Buckalew, Steven T. Mayer
-
Publication number: 20100032310Abstract: An apparatus for electroplating a layer of metal on the surface of a wafer includes an ionically resistive ionically permeable element located in close proximity of the wafer (preferably within 5 mm of the wafer surface) which serves to modulate ionic current at the wafer surface, and a second cathode configured to divert a portion of current from the wafer surface. The ionically resistive ionically permeable element in a preferred embodiment is a disk made of a resistive material having a plurality of perforations formed therein, such that perforations do not form communicating channels within the body of the disk. The provided configuration effectively redistributes ionic current in the plating system allowing plating of uniform metal layers and mitigating the terminal effect.Type: ApplicationFiled: November 7, 2008Publication date: February 11, 2010Inventors: Jonathan Reid, Bryan Buckalew, Zhian He, Seyang Park, Seshasayee Varadarajan, Bryan Pennington, Thomas Ponnuswamy, Patrick Breiling, Glenn Ibarreta, Steven Mayer