Patents by Inventor Stephen Rossnagel

Stephen Rossnagel 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: 7405154
    Abstract: A contact metallurgy structure comprising a patterned dielectric layer having cavities on a substrate; a silicide or germanide layer such as of cobalt and/or nickel located at the bottom of cavities; a contact layer comprising Ti or Ti/TiN located on top of the dielectric layer and inside the cavities and making contact to the silicide or germanide layer on the bottom; a diffusion barrier layer located on top of the contact layer and inside the cavities; optionally a seed layer for plating located on top of the barrier layer; a metal fill layer in vias is provided along with a method of fabrication. The metal fill layer is electrodeposited with at least one member selected from the group consisting of copper, rhodium, ruthenium, iridium, molybdenum, gold, silver, nickel, cobalt, silver, gold, cadmium and zinc and alloys thereof. When the metal fill layer is rhodium, ruthenium, or iridium, an effective diffusion barrier layer is not required between the fill metal and the dielectric.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: July 29, 2008
    Assignee: International Business Machines Corporation
    Inventors: Cyril Cabral, Jr., Hariklia Deligianni, Randolph F. Knarr, Sandra G. Malhotra, Stephen Rossnagel, Xiaoyan Shao, Anna Topol, Philippe M. Vereecken
  • Publication number: 20070290233
    Abstract: A reversible fuse structure in an integrated circuit is obtained through the implementation of a fuse cell having a short thin line of phase change materials in contact with via and line structures capable of passing current through the line of phase change material (fuse cell). The current is passed through the fuse cell in order to change the material from a less resistive material to a more resistive material through heating the phase change material in the crystalline state to the melting point then quickly quenching the material into the amorphous state. The reversible programming is achieved by passing a lower current through the fuse cell to convert the high resistivity amorphous material to a lower resistivity crystalline material. Appropriate sense-circuitry is integrated to read the information stored in the fuses, wherein said sense circuitry is used to enable or disable circuitry.
    Type: Application
    Filed: August 23, 2007
    Publication date: December 20, 2007
    Inventors: Geoffrey Burr, Chandrasekharan Kothandaraman, Chung Hon Lam, Xiao Hu Liu, Stephen Rossnagel, Christy Tyberg, Robert Wisnieff
  • Publication number: 20070246748
    Abstract: A memory cell comprises a dielectric layer and a phase change material. The dielectric layer defines a trench having both a wide portion and a narrow portion. The narrow portion is substantially narrower than the wide portion. The phase change material, in turn, at least partially fills the wide and narrow portions of the trench. What is more, the phase change material within the narrow portion of the trench defines a void. Data can be stored in the memory cell by heating the phase change material by applying a pulse of switching current to the memory cell. Advantageously, embodiments of the invention provide high switching current density and heating efficiency so that the magnitude of the switching current pulse can be reduced.
    Type: Application
    Filed: April 25, 2006
    Publication date: October 25, 2007
    Inventors: Matthew Breitwisch, Chung Lam, Jan Philipp, Stephen Rossnagel, Alejandro Schrott
  • Publication number: 20070222066
    Abstract: A contact metallurgy structure comprising a patterned dielectric layer having cavities on a substrate; a silicide or germanide layer such as of cobalt and/or nickel located at the bottom of cavities; a contact layer comprising Ti or Ti/TiN located on top of the dielectric layer and inside the cavities and making contact to the silicide or germanide layer on the bottom; a diffusion barrier layer located on top of the contact layer and inside the cavities; optionally a seed layer for plating located on top of the barrier layer; a metal fill layer in vias is provided along with a method of fabrication. The metal fill layer is electrodeposited with at least one member selected from the group consisting of copper, rhodium, ruthenium, iridium, molybdenum, gold, silver, nickel, cobalt, silver, gold, cadmium and zinc and alloys thereof. When the metal fill layer is rhodium, ruthenium, or iridium, an effective diffusion barrier layer is not required between the fill metal and the dielectric.
    Type: Application
    Filed: March 24, 2006
    Publication date: September 27, 2007
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, Hariklia Deligianni, Randolph Knarr, Sandra Malhotra, Stephen Rossnagel, Xiaoyan Shao, Anna Topol, Philippe Vereecken
  • Publication number: 20070166995
    Abstract: A process for the formation of an interconnect in a semiconductor structure including the steps of forming a dielectric layer on a substrate, forming a first barrier layer on the dielectric layer, forming a second barrier layer on the first barrier layer, wherein the second barrier layer is selected from the group consisting of ruthenium, platinum, palladium, rhodium and iridium and wherein the formation of the second barrier layer is manipulated so that the bulk concentration of oxygen in the second barrier layer is 20 atomic percent or less, and forming a conductive layer on the second barrier layer. The process may additionally include a step of treating the second barrier to reduce the amount of oxide on the surface of the second barrier layer.
    Type: Application
    Filed: January 17, 2006
    Publication date: July 19, 2007
    Applicant: International Business Machines Corporation
    Inventors: Sandra Malhotra, Hariklia Deligianni, Stephen Rossnagel, Xiaoyan Shao, Tsong-Lin Tai, Oscar van der Straten
  • Publication number: 20060278895
    Abstract: A reversible fuse structure in an integrated circuit is obtained through the implementation of a fuse cell having a short thin line of phase change materials in contact with via and line structures capable of passing current through the line of phase change material (fuse cell). The current is passed through the fuse cell in order to change the material from a less resistive material to a more resistive material through heating the phase change material in the crystalline state to the melting point then quickly quenching the material into the amorphous state. The reversible programming is achieved by passing a lower current through the fuse cell to convert the high resistivity amorphous material to a lower resistivity crystalline material. Appropriate sense-circuitry is integrated to read the information stored in the fuses, wherein said sense circuitry is used to enable or disable circuitry.
    Type: Application
    Filed: June 14, 2005
    Publication date: December 14, 2006
    Inventors: Geoffrey Burr, Chandrasekharan Kothandaraman, Chung Lam, Xiao Liu, Stephen Rossnagel, Christy Tyberg, Robert Wisnieff
  • Publication number: 20060264048
    Abstract: In an interconnect structure of an integrated circuit, a diffusion barrier film in a damascene structure is formed of a film having the composition TaNx, where x is greater than 1.2 and with a thickness of 0.5 to 5 nm.
    Type: Application
    Filed: July 31, 2006
    Publication date: November 23, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, Steffen Kaldor, Hyungjun Kim, Stephen Rossnagel
  • Publication number: 20060226409
    Abstract: Disclosed are a phase change memory cell and a method of forming the memory cell. The memory cell comprises a main body of phase change material connected directly to a bottom contact and via a narrow channel of phase change material to a top contact. The channel is tapered from the top contact towards the main body. A minimum width of the channel has a less than minimum lithographic dimension and is narrower than a width of the main body. Therefore, the channel provides a confined region for the switching current path and restricts phase changing to within the channel. In addition an embodiment of the memory cell isolates the main body of phase change material by providing a space between the phase change material and the cell walls. The space allows the phase change material to expand and contract and also limits heat dissipation.
    Type: Application
    Filed: April 6, 2005
    Publication date: October 12, 2006
    Applicant: International Business Machines Corporation
    Inventors: Geoffrey Burr, Chung Lam, Stephen Rossnagel, Alejandro Schrott
  • Publication number: 20060160350
    Abstract: Disclosed is a procedure to coat the free surface of Cu damascene lines by a 1-5 nm thick element prior to deposition of the inter-level dielectric or dielectric diffusion barrier layer. The coating provides protection against oxidation, increases the adhesion strength between the Cu and dielectric, and reduces interface diffusion of Cu. In addition, the thin cap layer further increases electromigration Cu lifetime and reduces the stress induced voiding. The selective elements can be directly deposited onto the Cu embedded within the under layer dielectric without causing an electric short circuit between the Cu lines. These chosen elements are based on their high negative reduction potentials with oxygen and water, and a low solubility in and formation of compounds with Cu.
    Type: Application
    Filed: January 18, 2005
    Publication date: July 20, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: John Bruley, Roy Carruthers, Lynne Gignac, Chao-Kun Hu, Eric Liniger, Sandra Malhotra, Stephen Rossnagel
  • Publication number: 20060003557
    Abstract: The present invention provides metallic films containing a Group IVB or VB metal, silicon and optionally nitrogen by utilizing atomic layer deposition (ALD). In particularly, the present invention provides a low temperature thermal ALD method of forming metallic silicides and a plasma-enhanced atomic layer deposition (PE-ALD) method of forming metallic silicon nitride film. The methods of the present invention are capable of forming metallic films having a thickness of a monolayer or less on the surface of a substrate. The metallic films provided in the present invention can be used for contact metallization, metal gates or as a diffusion barrier.
    Type: Application
    Filed: August 29, 2005
    Publication date: January 5, 2006
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, Hyungjun Kim, Stephen Rossnagel
  • Publication number: 20050269703
    Abstract: Methods of depositing a tantalum-nitride (TaN) diffusion barrier region on low-k materials. The methods include forming a protective layer on the low-k material substrate by performing plasma-enhanced atomic layer deposition (PE-ALD) from tantalum-based precursor and a nitrogen plasma in a chamber. The protective layer has a nitrogen content greater than its tantalum content. A substantially stoichiometric tantalum-nitride layer is then formed by performing PE-ALD from the tantalum-based precursor and a plasma including hydrogen and nitrogen. The invention also includes the tantalum-nitride diffusion barrier region so formed. In one embodiment, the metal precursor includes tantalum penta-chloride (TaCl5). The invention generates a sharp interface between low-k materials and liner materials.
    Type: Application
    Filed: June 2, 2004
    Publication date: December 8, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Derren Dunn, Hyungjun Kim, Stephen Rossnagel, Soon-Cheon Seo
  • Publication number: 20050118807
    Abstract: A method to deposit nucleation problem free ruthenium by ALD. The nucleation problem free, relatively smooth ruthenium ALD film is deposited by the use of plasma-enhanced ALD of ruthenium underlay for consequent thermal ruthenium ALD layer. In addition, oxygen or nitrogen plasma treatments of SiO2 or other dielectrics leads to uniform ALD ruthenium deposition. The method has application as a direct plating layer for a copper interconnect or metal gate structure for advanced CMOS devices.
    Type: Application
    Filed: November 28, 2003
    Publication date: June 2, 2005
    Inventors: Hyungiun Kim, Stephen Rossnagel
  • Publication number: 20050110144
    Abstract: In an interconnect structure of an integrated circuit, a diffusion barrier film in a damascene structure is formed of a film having the composition TaNx, where x is greater than 1.2 and with a thickness of 0.5 to 5 nm.
    Type: Application
    Filed: November 21, 2003
    Publication date: May 26, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, Steffen Kaldor, Hyungjun Kim, Stephen Rossnagel
  • Publication number: 20050112862
    Abstract: A hardmask layer in the back end of an integrated circuit is formed from TaN having a composition of less than 50% Ta and a resistivity greater than 400 ?Ohm-cm, so that it is substantially transparent in the visible and permits visual alignment of upper and lower alignment marks through the hardmask and intervening layer(s) of ILD. A preferred method of formation of the hardmask is by sputter deposition of Ta in an ambient containing N2 and a flow rate such that (N2 flow)/(N2+carrier flow)>0.5.
    Type: Application
    Filed: November 21, 2003
    Publication date: May 26, 2005
    Applicants: INTERNATIONAL BUSINESS MACHINES CORPORATION, INFINEON TECHNOLOGIES NORTH AMERICA CORP.
    Inventors: Lawrence Clevenger, Andrew Cowley, Timothy Dalton, Mark Hoinkis, Steffen Kaldor, Kaushik Kumar, Stephen Rossnagel, Andrew Simon, Douglas La Tulipe
  • Publication number: 20050095443
    Abstract: A method to deposit TaN by plasma enhanced layer with various nitrogen content. Using a mixture of hydrogen and nitrogen plasma, the nitrogen content in the film can be controlled from 0 to N/Ta=1.7. By turning off the nitrogen flow during deposition of TaN, a TaN/Ta bilayer is easily grown, which has copper diffusion barrier properties superior to those of a single Ta layer or a single TaN layer.
    Type: Application
    Filed: October 31, 2003
    Publication date: May 5, 2005
    Inventors: Hyungjun Kim, Andrew Kellock, Stephen Rossnagel
  • Publication number: 20050070097
    Abstract: The present invention relates to a very thin multilayer diffusion barrier for a semiconductor device and fabrication method thereof. The multilayer diffusion barrier according to the present invention is fabricated by forming a very thin, multilayer diffusion barrier composed of even thinner sub-layers, where the sub-layers are only a few atoms thick. The present invention provides a diffusion barrier layer for a semiconductor device which is in a substantially amorphous state and thermodynamically stable, even at high temperatures.
    Type: Application
    Filed: September 29, 2003
    Publication date: March 31, 2005
    Inventors: Katayun Barmak, Hyungjun Kim, Ismail Noyan, Stephen Rossnagel
  • Publication number: 20050042865
    Abstract: The present invention provides metallic films containing a Group IVB or VB metal, silicon and optionally nitrogen by utilizing atomic layer deposition (ALD). In particularly, the present invention provides a low temperature thermal ALD method of forming metallic silicides and a plasma-enhanced atomic layer deposition (PE-ALD) method of forming metallic silicon nitride film. The methods of the present invention are capable of forming metallic films having a thickness of a monolayer or less on the surface of a substrate. The metallic films provided in the present invention can be used for contact metallization, metal gates or as a diffusion barrier.
    Type: Application
    Filed: August 19, 2003
    Publication date: February 24, 2005
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Cyril Cabral, Hyungjun Kim, Stephen Rossnagel