Patents by Inventor Thomas A. Torack

Thomas A. Torack 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: 8186661
    Abstract: A wafer holder for holding a semiconductor wafer during a thermal wafer treatment process. The wafer holder includes at least three wafer supports. Each wafer support includes an upright shaft and a plurality of flexible fibers supported by the shaft in positions such that at least some of the fibers engage the semiconductor wafer when the wafer rests on the wafer supports.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: May 29, 2012
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: John A. Pitney, Thomas A. Torack
  • Patent number: 8080464
    Abstract: Methods are provided for etching and/or depositing an epitaxial layer on a silicon-on-insulator structure comprising a handle wafer, a silicon layer, and a dielectric layer between the handle wafer and the silicon layer. The silicon layer has a cleaved surface defining an outer surface of the structure. The cleaved surface of wafer is then etched while controlling a temperature of the reactor such that the etching reaction is kinetically limited. An epitaxial layer is then deposited on the wafer while controlling the temperature of the reactor such that a rate of deposition on the cleaved surface is kinetically limited.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: December 20, 2011
    Assignee: MEMC Electronics Materials, Inc,
    Inventors: Swapnil Y. Dhumal, Lawrence P. Flannery, Thomas A. Torack, John A. Pitney
  • Publication number: 20110159668
    Abstract: Methods are provided for etching and/or depositing an epitaxial layer on a silicon-on-insulator structure comprising a handle wafer, a silicon layer, and a dielectric layer between the handle wafer and the silicon layer. The silicon layer has a cleaved surface defining an outer surface of the structure. The cleaved surface of wafer is then etched while controlling a temperature of the reactor such that the etching reaction is kinetically limited. An epitaxial layer is then deposited on the wafer while controlling the temperature of the reactor such that a rate of deposition on the cleaved surface is kinetically limited.
    Type: Application
    Filed: December 17, 2010
    Publication date: June 30, 2011
    Applicant: MEMC ELECTRONIC MATERIALS, INC.
    Inventors: Swapnil Y. Dhumal, Lawrence P. Flannery, Thomas A. Torack, John A. Pitney
  • Publication number: 20110148128
    Abstract: A system and a wand are disclosed for the transport of a semiconductor wafer. The system and wand include a plate and a locator. The plate includes a plurality of plate outlets for directing gas flow against the wafer to hold the wafer using the Bernoulli principle. The locator extends from the plate and includes a locating outlet for directing a gas flow to locate the wafer laterally relative to the plate. The plate outlets and the locating outlet operate to prevent the wafer from contacting the plate or the locator. In some embodiments, a plurality of locators are used to locate the wafer laterally relative to the plate.
    Type: Application
    Filed: December 23, 2009
    Publication date: June 23, 2011
    Applicant: MEMC ELECTRONIC MATERIALS, INC.
    Inventors: Lance G. Hellwig, Thomas A. Torack, John A. Pitney
  • Publication number: 20100065696
    Abstract: A wafer holder for holding a semiconductor wafer during a thermal wafer treatment process. The wafer holder includes at least three wafer supports. Each wafer support includes an upright shaft and a plurality of flexible fibers supported by the shaft in positions such that at least some of the fibers engage the semiconductor wafer when the wafer rests on the wafer supports.
    Type: Application
    Filed: September 16, 2008
    Publication date: March 18, 2010
    Applicant: MEMC ELECTRONIC MATERIALS, INC
    Inventors: John A. Pitney, Thomas A. Torack
  • Publication number: 20080314319
    Abstract: A susceptor for supporting a semiconductor wafer in a heated chamber having an interior space. The susceptor includes a body having an upper surface and a lower surface opposite the upper surface. The susceptor also has a recess extending downward from the upper surface into the body along an imaginary central axis. The recess is sized and shaped for receiving the semiconductor wafer therein. The susceptor includes a plurality of lift pin openings extending through the body from the recess to the lower surface. Each of the lift pin openings is sized for accepting lift pins to selectively lift and lower the wafer with respect to the recess. The susceptor has a central opening extending through the body along the central axis from the recess to the lower surface.
    Type: Application
    Filed: December 27, 2007
    Publication date: December 25, 2008
    Applicant: MEMC ELECTRONIC MATERIALS, INC.
    Inventors: Manabu Hamano, Srikanth Kommu, John A. Pitney, Thomas A. Torack, Lance G. Hellwig
  • Patent number: 6743495
    Abstract: A process for manufacturing silicon wafers that reduces the size of silicon wafer surface and/or sub-surface defects without the forming excessive haze. The process entails cleaning the front surface of the silicon wafer at a temperature of at least about 1100° C. by exposing the front surface to a cleaning ambient comprising H2, HF gas, or HCl gas to remove silicon oxide from the front surface and exposing the cleaned front surface of the silicon wafer at a temperature of at least about 1100° C. to a vacuum or an annealing ambient consisting essentially of a mono-atomic noble gas selected from the group consisting of He, Ne, Ar, Kr, and Xe to facilitate the migration of silicon atoms to the exposed agglomerated defects without substantially etching silicon from the front surface of the heated silicon wafer.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: June 1, 2004
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Jiri L. Vasat, Andrei Stefanescu, Thomas A. Torack, Gregory M. Wilson
  • Publication number: 20020174828
    Abstract: A process for manufacturing silicon wafers that reduces the size of silicon wafer surface and/or sub-surface defects without the forming excessive haze. The process entails cleaning the front surface of the silicon wafer at a temperature of at least about 1100 ° C. by exposing the front surface to a cleaning ambient comprising H2, HF gas, or HCl gas to remove silicon oxide from the front surface and exposing the cleaned front surface of the silicon wafer at a temperature of at least about 1100 ° C. to a vacuum or an annealing ambient consisting essentially of a mono-atomic noble gas selected from the group consisting of He, Ne, Ar, Kr, and Xe to facilitate the migration of silicon atoms to the exposed agglomerated defects without substantially etching silicon from the front surface of the heated silicon wafer.
    Type: Application
    Filed: March 29, 2002
    Publication date: November 28, 2002
    Applicant: MEMC Electronic Materials, Inc.
    Inventors: Jiri L. Vasat, Andrei Stefanescu, Thomas A. Torack, Gregory M. Wilson
  • Patent number: 6086678
    Abstract: A system for equalizing pressure across a gate adapted to selectively block a port connecting a wafer handling chamber to a process chamber of a reactor for depositing an epitaxial layer on a semiconductor wafer positioned in the process chamber. The system comprises a bypass passage connecting the process chamber to the wafer handling chamber for transporting gas between the process chamber and the wafer handling chamber when the gate is blocking the port connecting the wafer handling chamber to the process chamber of the reactor for equalizing pressure between the process chamber and the wafer handling chamber. The system also includes a bypass valve positioned along the bypass passage for selectively controlling gas flow through the bypass passage.
    Type: Grant
    Filed: March 4, 1999
    Date of Patent: July 11, 2000
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Gregory M. Wilson, Michael J. Ries, Thomas A. Torack
  • Patent number: 5891250
    Abstract: A reactor for depositing an epitaxial layer on a semiconductor wafer contained within the reactor during a chemical vapor deposition process. The reactor comprises a reaction chamber sized and shaped for receiving a semiconductor wafer and an inlet passage in communication with the reaction chamber for delivering reactant gas to the reaction chamber. In addition the reactor includes a susceptor positioned in the reaction chamber for supporting the semiconductor wafer during the chemical vapor deposition process. Further, the reactor comprises an injector including a metering plate generally blocking reactant gas flow through the inlet passage. The plate has a slot extending through the plate totally within a periphery of the plate. The slot is sized for selectively restricting reactant gas flow past the plate thereby to meter reactant gas delivery to the chamber.
    Type: Grant
    Filed: May 5, 1998
    Date of Patent: April 6, 1999
    Assignee: MEMC Electronic Materials, Inc.
    Inventors: Charles R. Lottes, Thomas A. Torack