Patents by Inventor Swaminathan Sivakumar

Swaminathan Sivakumar 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: 20050148169
    Abstract: The present invention relates to the reduction of critical dimensions and the reduction of feature sizes in manufacturing integrated circuits. Specifically, the method controls photoresist flow rates to develop critical dimensions beyond the resolution limits of the photoresist material used, and the limits of lithographic tool sets. The post exposure and developed resist pattern is exposed to a solvent prior to a bake or reflow process. Exposure to the solvent lowers the molecular weight of the resist material, modifying the resist material's reflow rate. The post-exposure resist is then easier to control during a subsequent reflow process to reduce the hole or line size of the patterned resist.
    Type: Application
    Filed: December 30, 2003
    Publication date: July 7, 2005
    Inventors: Rex Frost, Swaminathan Sivakumar
  • Publication number: 20050148180
    Abstract: The present invention relates to exposing a bond pad on a substrate. A bond pad is formed over a silicon substrate with the subsequent formation of a dielectric over the bond pad. A patterned resist is formed, and at least opening is processed to form a sloped sidewall profile. The sloped sidewall profile is subsequently etched and transferred to the dielectric layer, exposing the bond pad.
    Type: Application
    Filed: December 30, 2003
    Publication date: July 7, 2005
    Inventors: Swaminathan Sivakumar, Curtis Ward, Timothy Hehr, Mark Fradkin
  • Publication number: 20050147928
    Abstract: The present invention relates to the reduction of critical dimensions and the reduction of feature sizes in manufacturing integrated circuits. Specifically, the method controls photoresist flow rates to develop critical dimensions beyond the resolution limits of the photoresist material used, and the limits of lithographic tool sets. The resist material characteristics are modified by exposing the resist pattern to either electrons, photons, or ions. The exposure modifies the glass transition temperature, cross linking characteristics, decomposition temperature, or molecular weight of the resist material. The post-exposure resist is then easier to control during a subsequent reflow process to reduce the hole size or line size of the patterned resist.
    Type: Application
    Filed: December 30, 2003
    Publication date: July 7, 2005
    Inventors: Rex Frost, Swaminathan Sivakumar
  • Publication number: 20050097502
    Abstract: Systems and techniques for accommodating diffraction in the printing of features on a substrate. In one implementation, a method includes identifying a pair of features to be printed using a corresponding pair of patterning elements and increasing a separation distance between the pair of patterning elements while maintaining the sufficiently small pitch between the corresponding imaged features. The pitch of the pair of features can be sufficiently small that, upon printing, diffraction will make a separation between the features smaller than a separation between the corresponding pair of patterning elements.
    Type: Application
    Filed: October 31, 2003
    Publication date: May 5, 2005
    Inventors: Rex Frost, Swaminathan Sivakumar
  • Publication number: 20050081178
    Abstract: A mask pattern may be decomposed into two or more masks, each having a pitch greater than that of the original mask pattern. New, “partial-pattern” masks may be created for each of the new mask patterns. The original mask pattern is transferred to the photoresist for the corresponding layer using a multiple exposure technique in which the photoresist is exposed with each of the partial-pattern masks individually, e.g., back-to-back in a pass through a scanner, to define all of the features in the original pattern.
    Type: Application
    Filed: October 8, 2003
    Publication date: April 14, 2005
    Inventors: Swaminathan Sivakumar, Rex Frost, Phi Nguyen
  • Publication number: 20040077173
    Abstract: By making a bottom anti-reflective coating that is soluble in aqueous solutions, the bottom anti-reflective coating may be removed in the same process used to remove the exposed photoresist. This may reduce defects and poor selectivity to photoresist in some embodiments during the etching of the bottom anti-reflective coating and avoids the need to separately etch the exposed bottom anti-reflective coating in some embodiments.
    Type: Application
    Filed: October 17, 2002
    Publication date: April 22, 2004
    Inventor: Swaminathan Sivakumar
  • Publication number: 20030213968
    Abstract: A semiconductor wafer may be coated with an imageable anti-reflective coating. As a result, the coating may be removed using the same techniques used to remove overlying photoresists. This may overcome the difficulty of etching anti-reflective coatings using standard etches because of their poor selectivity to photoresist and the resulting propensity to cause integrated circuit defects arising from anti-reflective coating remnants.
    Type: Application
    Filed: May 17, 2002
    Publication date: November 20, 2003
    Inventor: Swaminathan Sivakumar
  • Publication number: 20030207584
    Abstract: Looser and tighter pitch geometries in semiconductor layouts may be fractured into separate groups and defined separately on at least two separate photomasks. Thereafter, the looser pitch geometries may be exposed using a first mask and the tighter pitch geometries may be exposed using a second mask. The conditions of exposure may be optimized for the different geometries. As a result, the customized exposures for each type of geometry may be optimized without some of the compromises conventionally required.
    Type: Application
    Filed: May 1, 2002
    Publication date: November 6, 2003
    Inventors: Swaminathan Sivakumar, Mark Bohr
  • Patent number: 5933759
    Abstract: The present invention describes a method for forming submicron critical dimension shallow trenches with improved etch selectivity and etch bias control. In one embodiment of the present invention, three separate etch steps are performed. A polish stop layer (or an etch hard mask layer) and an oxide layer are etched during the first and second etch steps and the underlying substrate is etched during the third etch step. In the first etch step a carbon-fluorine based etchant is used in order to form a polymer layer along the photoresist, polish stop layer (or etch hard mask layer), and oxide layer. After the first etch step, a second etch step is used to remove the polymer from the horizontal surfaces of the semiconductor structures thereby forming polymer sidewalls as well as completing the etching of the polish stop layer (or etch hard mask layer) and the oxide layer.
    Type: Grant
    Filed: December 31, 1996
    Date of Patent: August 3, 1999
    Assignee: Intel Corporation
    Inventors: Phi L. Nguyen, Ralph A. Schweinfurth, Swaminathan Sivakumar