Patents by Inventor Pushkara Rao Varanasi

Pushkara Rao Varanasi 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: 7320855
    Abstract: A top anti-reflective coating material (TARC) and barrier layer, and the use thereof in lithography processes, is disclosed. The TARC/barrier layer may be especially useful for immersion lithography using water as the imaging medium. The TARC/barrier layer comprises a polymer which comprises at least one silicon-containing moiety and at least one aqueous base soluble moiety. Suitable polymers include polymers having a silsesquioxane (ladder or network) structure, such as polymers containing monomers having the structure: where R1 comprises an aqueous base soluble moiety, and x is from about 1 to about 1.95, more preferably from about 1 to about 1.75.
    Type: Grant
    Filed: November 3, 2004
    Date of Patent: January 22, 2008
    Assignee: International Business Machines Corporation
    Inventors: Wu-Song S. Huang, Sean D. Burns, Pushkara Rao Varanasi
  • Patent number: 7217496
    Abstract: A photoresist composition including a polymer is disclosed, wherein the polymer includes at least one monomer having the formula: where R1 represents hydrogen (H), a linear, branched or cyclo alkyl group of 1 to 20 carbons, a semi- or perfluorinated linear, branched or cyclo alkyl group of 1 to 20 carbons or CN; R2 represents an alicyclic group of 5 or more carbon atoms; X represents a methylene, ether, ester, amide or carbonate linkage; R3 represents a linear or branched alkylene group or semi- or perfluorinated linear or branched alkylene group with 1 or more carbon atoms; R4 represents hydrogen (H), methyl (CH3), trifluoromethyl (CF3), difluoromethyl (CHF2), fluoromethyl (CH2F), or a semi- or perflourinated aliphatic group; R5 represents trifluoromethyl (CF3), difluoromethyl (CHF2), fluoromethyl (CH2F), or a semi- or perfluorinated substituted or unsubstituted aliphatic group; n represents an integer of 1 or more; and OR12 represents OH or at least one acid labile group selected from a tertiary alkyl c
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: May 15, 2007
    Assignee: International Business Machines Corporation
    Inventors: Mahmoud Khojasteh, Pushkara Rao Varanasi, Wenjie Li, Kuang-Jung J Chen, Kaushal S. Patel
  • Patent number: 7183036
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation (and possibly other radiation) at low energy levels are obtained using a polymer having acrylate/methacrylate monomeric units comprising a low activation energy moiety preferably attached to a naphthalene ester group. The resist allows the performance benefit of acrylate/methacrylate polymers with low activation energy for imaging thereby enabling improved resolution and reduced post-exposure bake sensitivity. The resist polymer also preferably contains monomeric units comprising fluoroalcohol moiety and a monomeric units comprising a lactone moiety.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: February 27, 2007
    Assignee: International Business Machines Corporation
    Inventors: Mahmoud Khojasteh, Kuang-Jung Chen, Pushkara Rao Varanasi
  • Patent number: 7129016
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation are obtained using a polymer having acrylate/methacrylate monomeric units comprising a naphthol ester group. The resist may optionally contain polymer having acrylate/methacrylate monomeric units with fluorine-containing functional groups. The resists containing the polymer having acrylate/methacrylate monomeric units comprising a naphthol ester group have an improved process window, including improved etch resistance and reduced swelling compared to conventional fluorine-containing 193 nm resist.
    Type: Grant
    Filed: November 12, 2004
    Date of Patent: October 31, 2006
    Assignee: International Business Machines Corporation
    Inventors: Mahmoud Khojasteh, Kuang-Jung Chen, Pushkara Rao Varanasi
  • Patent number: 7087356
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation and/or possibly other radiation and are developable to form resist structures of improved development characteristics and improved etch resistance are enabled by the use of resist compositions containing imaging polymer component comprising an acid-sensitive polymer having a monomeric unit with a pendant group containing a remote acid labile moiety.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: August 8, 2006
    Assignees: International Business Machines Corporation, JSR Corporation
    Inventors: Mahmoud H. Khojasteh, Kuang-Jung Chen, Pushkara Rao Varanasi, Yukio Nishimura, Eiichi Kobayashi
  • Patent number: 7063931
    Abstract: A positive photoresist composition comprises a radiations sensitive acid generator, and a polymer that may include a first repeating unit derived from a sulfonamide monomer including a fluorosulfonamide functionality, and a second repeating unit, which may include a pendant acid-labile moiety. The positive photoresist composition may also comprise at least one of a solvent, a quencher, and a surfactant. A patterned photoresist layer, made of the positive photoresist composition, may be formed on a substrate, the positive photoresist layer may be exposed to a pattern of imaging radiation, a portion of the positive photoresist layer that is exposed to the pattern of imaging radiation may be removed to reveal a correspondingly patterned substrate for subsequent processing in the manufacture of a semiconductor device.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: June 20, 2006
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi
  • Patent number: 6949325
    Abstract: A negative resist composition is disclosed, wherein the resist composition includes a polymer having at least one fluorosulfonamide monomer unit having one of the following two formulae: wherein: M is a polymerizable backbone moiety; Z is a linking moiety selected from the group consisting of —C(O)O—, —C(O)—, —OC(O)—, —O—C(O)—C(O)—O—, or alkyl; P is 0 or 1; R1 is a linear or branched alkyl group of 1 to 20 carbons; R2 is hydrogen, fluorine, a linear or branched alkyl group of 1 to 6 carbons, or a semi- or perfluorinated linear or branched alkyl group of 1 to 6 carbons; and n is an integer from 1 to 6.
    Type: Grant
    Filed: September 16, 2003
    Date of Patent: September 27, 2005
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi
  • Patent number: 6927015
    Abstract: Compositions suitable for forming planarizing underlayers for multilayer lithographic processes are characterized by the presence of (A) a polymer containing: (i) cyclic ether moieties, (ii) saturated polycyclic moieties, and (iii) aromatic moieties for compositions not requiring a separate crosslinker, or (B) a polymer containing: (i) saturated polycyclic moieties, and (ii) aromatic moieties for compositions requiring a separate crosslinker. The compositions provide outstanding optical, mechanical and etch selectivity properties. The compositions are especially useful in lithographic processes using radiation less than 200 nm in wavelength to configure underlying material layers.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: August 9, 2005
    Assignee: International Business Machines Corporation
    Inventors: Mahmoud M. Khojasteh, Timothy M. Hughes, Ranee W. Kwong, Pushkara Rao Varanasi, William R. Brunsvold, Margaret C. Lawson, Robert D. Allen, David R. Medeiros, Ratnam Sooriyakumaran, Phillip Brock
  • Patent number: 6902874
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation and/or possibly other radiation and are developable to form resist structures of improved development characteristics and improved etch resistance are enabled by the use of resist compositions containing imaging polymer having a 2-cyano acrylic monomer.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: June 7, 2005
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi
  • Patent number: 6818381
    Abstract: Compositions suitable for forming planarizing underlayers for multilayer lithographic processes are characterized by the presence of (A) a polymer containing: (i) cyclic ether moieties, (ii) saturated polycyclic moieties, and (iii) aromatic moieties for compositions not requiring a separate crosslinker, or (B) a polymer containing: (i) saturated polycyclic moieties, and (ii) aromatic moieties for compositions requiring a separate crosslinker. The compositions provide outstanding optical, mechanical and etch selectivity properties. The compositions are especially useful in lithographic processes using radiation less than 200 nm in wavelength to configure underlying material layers.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: November 16, 2004
    Assignee: International Business Machines Corporation
    Inventors: Mahmoud M. Khojasteh, Timothy M. Hughes, Ranee W. Kwong, Pushkara Rao Varanasi, William R. Brunsvold, Margaret C. Lawson, Robert D. Allen, David R. Medeiros, Ratnam Sooriyakumaran, Phillip Brock
  • Patent number: 6770418
    Abstract: Acid-catalyzed positive resist compositions suitable for bilayer or multilayer lithographic applications are enabled by the use of a combination of (a) an acid-sensitive imaging polymer, (b) a radiation-sensitive acid generator, and (c) a non-polymeric silicon additive. The imaging polymer is preferably imageable with 193 nm or shorter wavelength imaging radiation. The resist compositions preferably contain at least about 5 wt. % silicon based on the weight of the imaging polymer. The compositions generally provide reduced line edge roughness compared to conventional silicon-containing resists.
    Type: Grant
    Filed: December 21, 2001
    Date of Patent: August 3, 2004
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi, Ranee Kwong
  • Patent number: 6770419
    Abstract: The silicon-containing resist compositions which have low silicon outgassing and high resolution lithographic performance, especially in bilayer or multilayer lithographic applications using 193 nm or shorter wavelength imaging radiation are enabled by the presence of an imaging polymer having silicon-containing, non-acid-labile pendant groups. The resist compositions of the invention are preferably further characterized by the substantial absence of silicon-containing acid-labile moieties.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: August 3, 2004
    Assignee: International Business Machines Corporation
    Inventors: Mahmoud M. Khojasteh, Ranee W. Kwong, Kuang-Jung Chen, Pushkara Rao Varanasi, Robert D. Allen, Phillip Brock, Frances Houle, Ratnam Sooriyakumaran
  • Patent number: 6756180
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation (and possibly other radiation) and are developable to form resist structures of improved development characteristics, improved etch resistance, and reduced post-exposure bake sensitivity are enabled by the use of resist compositions containing an imaging polymer having cyclic olefin monomeric units respectively having pendant, acid-labile protecting moieties, lactone moieties and fluoroalcohol moieties. The lactone moiety is preferably a pendant lactone ester.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: June 29, 2004
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi, Masafumi Yamamoto
  • Publication number: 20040076903
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation (and possibly other radiation) and are developable to form resist structures of improved development characteristics, improved etch resistance, and reduced post-exposure bake sensitivity are enabled by the use of resist compositions containing an imaging polymer having cyclic olefin monomeric units respectively having pendant, acid-labile protecting moieties, lactone moieties and fluoroalcohol moieties. The lactone moiety is preferably a pendant lactone ester.
    Type: Application
    Filed: October 22, 2002
    Publication date: April 22, 2004
    Applicants: International Business Machines Corporation, JSR Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi, Masafumi Yamamoto
  • Publication number: 20040072099
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation and/or possibly other radiation and are developable to form resist structures of improved development characteristics and improved etch resistance are enabled by the use of resist compositions containing imaging polymer having a 2-cyano acrylic monomer.
    Type: Application
    Filed: September 29, 2003
    Publication date: April 15, 2004
    Inventors: Wenjie Li, Pushkara Rao Varanasi
  • Publication number: 20040063024
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation and/or possibly other radiation and are developable to form resist structures of improved development characteristics and improved etch resistance are enabled by the use of resist compositions containing imaging polymer component comprising an acid-sensitive polymer having a monomeric unit with a pendant group containing a remote acid labile moiety.
    Type: Application
    Filed: September 30, 2002
    Publication date: April 1, 2004
    Applicants: International Business Machines Corporation, JSR Corporation
    Inventors: Mahmoud H. Khojasteh, Kuang-Jung Chen, Pushkara Rao Varanasi, Yukio Nishimura, Eiichi Kobayashi
  • Publication number: 20040048187
    Abstract: The silicon-containing resist compositions which have low silicon outgassing and high resolution lithographic performance, especially in bilayer or multilayer lithographic applications using 193 nm or shorter wavelength imaging radiation are enabled by the presence of an imaging polymer having silicon-containing, non-acid-labile pendant groups. The resist compositions of the invention are preferably further characterized by the substantial absence of silicon-containing acid-labile moieties.
    Type: Application
    Filed: September 11, 2002
    Publication date: March 11, 2004
    Inventors: Mahmoud M. Khojasteh, Ranee W. Kwong, Kuang-Jung Chen, Pushkara Rao Varanasi, Robert D. Allen, Phillip Brock, Frances Houle, Ratnam Sooriyakumaran
  • Patent number: 6696216
    Abstract: Thiophene-containing photo acid generators having either of the following general formulas: wherein at least one of R1, R2 or R3 is thiophene or thiophene that is substituted with alkyl, alkoxy or cycloalkyl, and the remaining R1, R2 or R3, not containing a thiophene moiety, are independently selected from the group consisting of alkyl, cycloalkyl and aryl, or at least one of R1, R2 or R3 are joined together to form a cyclic moiety having from about 4 to about 8 ring carbon atoms; and Y is a counter ion, are disclosed as well as the use thereof as a component of a chemically amplified resist composition. In addition to the thiophene-containing photo acid generator, the inventive composition includes a chemically amplified base polymer, a solvent, an optional photosensitizer, an optional base, an optional dissolution modifying agent and an optional surfactant.
    Type: Grant
    Filed: June 29, 2001
    Date of Patent: February 24, 2004
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi, Kuang-Jung Chen
  • Patent number: 6635401
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation and/or possibly other radiation and are developable to form resist structures of improved development characteristics and improved etch resistance are enabled by the use of resist compositions containing imaging polymer having a 2-cyano acrylic monomer.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: October 21, 2003
    Assignee: International Business Machines Corporation
    Inventors: Wenjie Li, Pushkara Rao Varanasi
  • Patent number: 6627391
    Abstract: Acid-catalyzed positive resist compositions which are imageable with 193 nm radiation and are developable to form resist structures of high resolution and high etch resistance are enabled by the use of a combination of (a) an imaging polymer comprising a monomer selected from the group consisting of a cyclic olefin, an acrylate and a methacrylate, (b) a radiation-sensitive acid generator, and (c) a lactone additive. The lactone additive preferably contains at least 10 carbon atoms and more preferably at least one saturated alicyclic moiety. The imaging polymer is preferably a cyclic olefin polymer.
    Type: Grant
    Filed: August 16, 2000
    Date of Patent: September 30, 2003
    Assignee: International Business Machines Corporation
    Inventors: Hiroshi Ito, Pushkara Rao Varanasi