Patents by Inventor Bhadri N. Varadarajan

Bhadri N. Varadarajan 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: 20150249013
    Abstract: Disclosed herein are methods of doping a fin-shaped channel region of a partially fabricated 3-D transistor on a semiconductor substrate. The methods may include forming a multi-layer dopant-containing film on the substrate, forming a capping film comprising a silicon carbide material, a silicon nitride material, a silicon carbonitride material, or a combination thereof, the capping film located such that the multi-layer dopant-containing film is located in between the substrate and the capping film, and driving dopant from the dopant-containing film into the fin-shaped channel region. Multiple dopant-containing layers of the film may be formed by an atomic layer deposition process which includes adsorbing a dopant-containing film precursor such that it forms an adsorption-limited layer on the substrate and reacting adsorbed dopant-containing film precursor.
    Type: Application
    Filed: February 28, 2014
    Publication date: September 3, 2015
    Inventors: Reza Arghavani, Samantha Tan, Bhadri N. Varadarajan, Adrien LaVoie, Ananda Banerji, Jun Qian, Shankar Swaminathan
  • Publication number: 20150221519
    Abstract: Vacuum-integrated photoresist-less methods and apparatuses for forming metal hardmasks can provide sub-30 nm patterning resolution. A metal-containing (e.g., metal salt or organometallic compound) film that is sensitive to a patterning agent is deposited on a semiconductor substrate. The metal-containing film is then patterned directly (i.e., without the use of a photoresist) by exposure to the patterning agent in a vacuum ambient to form the metal mask. For example, the metal-containing film is photosensitive and the patterning is conducted using sub-30 nm wavelength optical lithography, such as EUV lithography.
    Type: Application
    Filed: January 30, 2015
    Publication date: August 6, 2015
    Inventors: Jeffrey Marks, George Andrew Antonelli, Richard A. Gottscho, Dennis M. Hausmann, Adrien LaVoie, Thomas Joseph Knisley, Sirish K. Reddy, Bhadri N. Varadarajan, Artur Kolics
  • Patent number: 9050623
    Abstract: Porous ULK film is cured with UV radiation at progressively shorter wavelengths to obtain ULK films quickly at a desired dielectric constant with improved mechanical properties. At longer wavelengths above about 220 nm or about 240 nm, porogen is removed while minimizing silicon-carbon bond formation. At shorter wavelengths, mechanical properties are improved while dielectric constant increases.
    Type: Grant
    Filed: September 12, 2008
    Date of Patent: June 9, 2015
    Assignee: Novellus Systems, Inc.
    Inventor: Bhadri N. Varadarajan
  • Publication number: 20150118394
    Abstract: A thin layer of a silicon-carbon-containing film is deposited on a substrate by generating hydrogen radicals from hydrogen gas supplied to a radicals generation chamber, supplying the hydrogen radicals to a substrate processing chamber separate from the substrate processing chamber via a multiport gas distributor, and reacting the hydrogen radicals therein with an organosilicon reactant introduced into the substrate processing chamber concurrently. The hydrogen radicals are allowed to relax into a ground state in a radicals relaxation zone within the substrate processing chamber before reacting with the organosilicon reactant.
    Type: Application
    Filed: October 24, 2013
    Publication date: April 30, 2015
    Inventors: Bhadri N Varadarajan, Bo Gong
  • Publication number: 20140356549
    Abstract: Provided are methods and systems for providing silicon carbide class of films. The composition of the silicon carbide film can be controlled by the choice of the combination of precursors and the ratio of flow rates between the precursors. The silicon carbide films can be deposited on a substrate by flowing two different organo-silicon precursors to mix together in a reaction chamber. The organo-silicon precursors react with one or more radicals in a substantially low energy state to form the silicon carbide film. The one or more radicals can be formed in a remote plasma source.
    Type: Application
    Filed: May 31, 2013
    Publication date: December 4, 2014
    Inventor: Bhadri N. Varadarajan
  • Publication number: 20140235069
    Abstract: An apparatus for use with radical sources for supplying radicals during semiconductor processing operations is provided. The apparatus may include a stack of plates or components that form a faceplate assembly. The faceplate assembly may include a radical diffuser plate, a precursor delivery plate, and a thermal isolator interposed between the radical diffuser plate and the precursor delivery plate. The faceplate assembly may have a pattern of radical through-holes with centerlines substantially perpendicular to the radical diffuser plate. The thermal isolator may be configured to regulate heat flow between the radical diffuser plate and the precursor delivery plate.
    Type: Application
    Filed: July 3, 2013
    Publication date: August 21, 2014
    Inventors: Patrick G. Breiling, Bhadri N. Varadarajan, Jennifer L. Petraglia, Bart J. van Schravendijk, Karl F. Leeser, Mandyam Ammanjee Sriram, Rachel E. Batzer
  • Publication number: 20140020259
    Abstract: A processing system includes a chamber and a steam source that supplies steam in the chamber. A UV source directs UV light onto a deposited layer of a substrate in the presence of the steam from the steam source for a predetermined conversion period to at least partially convert the deposited layer.
    Type: Application
    Filed: July 31, 2013
    Publication date: January 23, 2014
    Applicant: Novellus Systems, Inc.
    Inventors: Bhadri N. Varadarajan, Bart Van Schravendijk
  • Patent number: 8528224
    Abstract: Systems and methods for processing a substrate include supplying steam in a chamber, arranging a substrate with a deposited layer that includes silicon in the chamber, and directing UV light onto the deposited layer in the presence of the steam for a predetermined conversion period to at least partially convert the deposited layer. Systems and methods for densifying a deposited layer of a substrate include supplying ammonia in a chamber, arranging the substrate that includes the deposited layer in the chamber, and directing UV light onto the deposited layer in the presence of the ammonia for a predetermined conversion period to at least partially densify the deposited layer.
    Type: Grant
    Filed: August 11, 2010
    Date of Patent: September 10, 2013
    Assignee: Novellus Systems, Inc.
    Inventors: Bhadri N. Varadarajan, Bart Van Schravendijk
  • Patent number: 8465991
    Abstract: A method for the ultraviolet (UV) treatment of carbon-containing low-k dielectric and associated apparatus enables process induced damage repair. The methods of the invention are particularly applicable in the context of damascene processing to recover lost low-k property of a dielectric damaged during processing, either pre-metallization, post-planarization, or both. UV treatments can include an exposure of the subject low-k dielectric to a constrained UV spectral profile and/or chemical silylating agent, or both.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: June 18, 2013
    Assignee: Novellus Systems, Inc.
    Inventors: Bhadri N. Varadarajan, Kevin M. McLaughlin, Bart van Schravendijk
  • Publication number: 20120036732
    Abstract: Systems and methods for processing a substrate include supplying steam in a chamber, arranging a substrate with a deposited layer that includes silicon in the chamber, and directing UV light onto the deposited layer in the presence of the steam for a predetermined conversion period to at least partially convert the deposited layer. Systems and methods for densifying a deposited layer of a substrate include supplying ammonia in a chamber, arranging the substrate that includes the deposited layer in the chamber, and directing UV light onto the deposited layer in the presence of the ammonia for a predetermined conversion period to at least partially densify the deposited layer.
    Type: Application
    Filed: August 11, 2010
    Publication date: February 16, 2012
    Inventors: Bhadri N. Varadarajan, Bart Van Schravendijk
  • Publication number: 20110117678
    Abstract: A method for the ultraviolet (UV) treatment of carbon-containing low-k dielectric and associated apparatus enables process induced damage repair. The methods of the invention are particularly applicable in the context of damascene processing to recover lost low-k property of a dielectric damaged during processing, either pre-metallization, post-planarization, or both. UV treatments can include an exposure of the subject low-k dielectric to a constrained UV spectral profile and/or chemical silylating agent, or both.
    Type: Application
    Filed: December 20, 2010
    Publication date: May 19, 2011
    Inventors: Bhadri N. Varadarajan, Kevin M. McLaughlin, Bart van Schravendijk
  • Patent number: 7327001
    Abstract: A salicide layer is deposited on the source/drain regions of a PMOS transistor. A dielectric capping layer having residual compressive stress is formed on the salicide layer by depositing a plurality of PECVD dielectric sublayers and plasma-treating each sublayer. Compressive stress from the dielectric capping layer is uniaxially transferred to the PMOS channel through the source-drain regions to create compressive strain in the PMOS channel. To form a compressive dielectric layer, a deposition reactant mixture containing A1 atoms and A2 atoms is provided in a vacuum chamber. Element A2 is more electronegative than element A1, and A1 atoms have a positive oxidation state and A2 atoms have a negative oxidation state when A1 atoms are bonded with A2 atoms. A deposition plasma is generated by applying HF and LF radio-frequency power to the deposition reactant mixture, and a sublayer of compressive dielectric material is deposited.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: February 5, 2008
    Assignee: Novellus Systems, Inc.
    Inventors: Akhil Singhal, James S. Sims, Bhadri N. Varadarajan
  • Patent number: 7214630
    Abstract: A salicide layer is deposited on the source/drain regions of a PMOS transistor. A dielectric capping layer having residual compressive stress is formed on the salicide layer by depositing a plurality of PECVD dielectric sublayers and plasma-treating each sublayer. Compressive stress from the dielectric capping layer is uniaxially transferred to the PMOS channel through the source-drain regions to create compressive strain in the PMOS channel. To form a compressive dielectric layer, a deposition reactant mixture containing A1 atoms and A2 atoms is provided in a vacuum chamber. Element A2 is more electronegative than element A1, and A1 atoms have a positive oxidation state and A2 atoms have a negative oxidation state when A1 atoms are bonded with A2 atoms. A deposition plasma is generated by applying HF and LF radio-frequency power to the deposition reactant mixture, and a sublayer of compressive dielectric material is deposited.
    Type: Grant
    Filed: May 6, 2005
    Date of Patent: May 8, 2007
    Assignee: Novellus Systems, Inc.
    Inventors: Bhadri N. Varadarajan, James S. Sims, Akhil Singhal