Patents by Inventor Christopher W. Leitz

Christopher W. Leitz 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: 8436336
    Abstract: The invention provides semiconductor structure comprising a strained Ge channel layer, and a gate dielectric disposed over the strained Ge channel layer. In one aspect of the invention, a strained Ge channel MOSFET is provided. The strained Ge channel MOSFET includes a relaxed SiGe virtual substrate with a Ge content between 50-95%, and a strained Ge channel formed on the virtual substrate. A gate structure is formed upon the strained Ge channel, whereupon a MOSFET is formed with increased performance over bulk Si. In another embodiment of the invention, a semiconductor structure comprising a relaxed Ge channel layer and a virtual substrate, wherein the relaxed Ge channel layer is disposed above the virtual substrate. In a further aspect of the invention, a relaxed Ge channel MOSFET is provided. The method includes providing a relaxed virtual substrate with a Ge composition of approximately 100% and a relaxed Ge channel formed on the virtual substrate.
    Type: Grant
    Filed: October 23, 2007
    Date of Patent: May 7, 2013
    Assignee: Massachusetts Institute of Technology
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Patent number: 7566606
    Abstract: A semiconductor structure includes a strain-inducing substrate layer having a germanium concentration of at least 10 atomic %. The semiconductor structure also includes a compressively strained layer on the strain-inducing substrate layer. The compressively strained layer has a germanium concentration at least approximately 30 percentage points greater than the germanium concentration of the strain-inducing substrate layer, and has a thickness less than its critical thickness. The semiconductor structure also includes a tensilely strained layer on the compressively strained layer. The tensilely strained layer may be formed from silicon having a thickness less than its critical thickness.
    Type: Grant
    Filed: October 6, 2006
    Date of Patent: July 28, 2009
    Assignee: AmberWave Systems Corporation
    Inventors: Matthew T. Currie, Anthony J. Lochtefeld, Christopher W. Leitz, Eugene A. Fitzgerald
  • Publication number: 20080135830
    Abstract: Semiconductor structures are formed with semiconductor layers having reduced compositional variation. Top surfaces of the semiconductor layers are substantially haze-free.
    Type: Application
    Filed: December 21, 2007
    Publication date: June 12, 2008
    Applicant: AmberWave Systems Corporation
    Inventors: Richard Westhoff, Christopher J. Vineis, Matthew T. Currie, Vicky K. Yang, Christopher W. Leitz
  • Publication number: 20080128747
    Abstract: The invention provides semiconductor structure comprising a strained Ge channel layer, and a gate dielectric disposed over the strained Ge channel layer. In one aspect of the invention, a strained Ge channel MOSFET is provided. The strained Ge channel MOSFET includes a relaxed SiGe virtual substrate with a Ge content between 50-95%, and a strained Ge channel formed on the virtual substrate. A gate structure is formed upon the strained Ge channel, whereupon a MOSFET is formed with increased performance over bulk Si. In another embodiment of the invention, a semiconductor structure comprising a relaxed Ge channel layer and a virtual substrate, wherein the relaxed Ge channel layer is disposed above the virtual substrate. In a further aspect of the invention, a relaxed Ge channel MOSFET is provided. The method includes providing a relaxed virtual substrate with a Ge composition of approximately 100% and a relaxed Ge channel formed on the virtual substrate.
    Type: Application
    Filed: October 23, 2007
    Publication date: June 5, 2008
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Patent number: 7332417
    Abstract: Semiconductor structures are formed with semiconductor layers having reduced compositional variation. Top surfaces of the semiconductor layers are substantially haze-free.
    Type: Grant
    Filed: January 27, 2004
    Date of Patent: February 19, 2008
    Assignee: AmberWave Systems Corporation
    Inventors: Richard Westhoff, Christopher J. Vineis, Matthew T. Currie, Vicky T. Yang, Christopher W. Leitz
  • Patent number: 7301180
    Abstract: The invention provides semiconductor structure comprising a strained Ge channel layer, and a gate dielectric disposed over the strained Ge channel layer. In one aspect of the invention, a strained Ge channel MOSFET is provided. The strained Ge channel MOSFET includes a relaxed SiGe virtual substrate with a Ge content between 50-95%, and a strained Ge channel formed on the virtual substrate. A gate structure is formed upon the strained Ge channel, whereupon a MOSFET is formed with increased performance over bulk Si. In another embodiment of the invention, a semiconductor structure comprising a relaxed Ge channel layer and a virtual substrate, wherein the relaxed Ge channel layer is disposed above the virtual substrate. In a further aspect of the invention, a relaxed Ge channel MOSFET is provided. The method includes providing a relaxed virtual substrate with a Ge composition of approximately 100% and a relaxed Ge channel formed on the virtual substrate.
    Type: Grant
    Filed: June 18, 2002
    Date of Patent: November 27, 2007
    Assignee: Massachusetts Institute of Technology
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Patent number: 7141820
    Abstract: A structure including a compressively strained semiconductor layer, the compressively strained layer having a strain greater than or equal to 0.25%. A tensilely strained semiconductor layer may be formed over the compressively strained layer. The compressively strained layer is substantially planar, having a surface roughness characterized in (i) having an average wavelength greater than an average wavelength of a carrier in the compressively strained layer and/or (ii) having an average height less than 10 nm.
    Type: Grant
    Filed: February 27, 2004
    Date of Patent: November 28, 2006
    Assignee: AmberWave Systems Corporation
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Patent number: 7138310
    Abstract: A semiconductor structure includes a strain-inducing substrate layer having a germanium concentration of at least 10 atomic %. The semiconductor structure also includes a compressively strained layer on the strain-inducing substrate layer. The compressively strained layer has a germanium concentration at least approximately 30 percentage points greater than the germanium concentration of the strain-inducing substrate layer, and has a thickness less than its critical thickness. The semiconductor structure also includes a tensilely strained layer on the compressively strained layer. The tensilely strained layer may be formed from silicon having a thickness less than its critical thickness.
    Type: Grant
    Filed: June 6, 2003
    Date of Patent: November 21, 2006
    Assignee: AmberWave Systems Corporation
    Inventors: Matthew T. Currie, Anthony J. Lochtefeld, Christopher W. Leitz, Eugene A. Fitzgerald
  • Patent number: 6916727
    Abstract: A structure includes a tensile strained layer disposed over a substrate, the tensile strained layer having a first thickness. A compressed layer is disposed between the tensile strained layer and the substrate, the compressed layer having a second thickness. The first and second thicknesses are selected to define a first carrier mobility in the tensile strained layer and a second carrier mobility in the compressed layer.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: July 12, 2005
    Assignee: Massachusetts Institute of Technology
    Inventors: Christopher W. Leitz, Minjoo L. Lee, Eugene A. Fitzgerald
  • Publication number: 20040214407
    Abstract: Semiconductor structures are formed with semiconductor layers having reduced compositional variation. Top surfaces of the semiconductor layers are substantially haze-free.
    Type: Application
    Filed: January 27, 2004
    Publication date: October 28, 2004
    Applicant: AmberWave Systems Corporation
    Inventors: Richard Westhoff, Christopher J. Vineis, Matthew T. Currie, Vicky K. Yang, Christopher W. Leitz
  • Publication number: 20040164318
    Abstract: A structure and a method for forming the structure, the method including forming a compressively strained semiconductor layer, the compressively strained layer having a strain greater than or equal to 0.25%. A tensilely strained semiconductor layer is formed over the compressively strained layer. The compressively strained layer is substantially planar, having a surface roughness characterized in (i) having an average wavelength greater than an average wavelength of a carrier in the compressively strained layer or (ii) having an average height less than 10 nm.
    Type: Application
    Filed: February 27, 2004
    Publication date: August 26, 2004
    Applicant: Massachusetts Institute of Technology
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Publication number: 20040115916
    Abstract: Misfit dislocations are selectively placed in layers formed over substrates. Thicknesses of layers may be used to define distances between misfit dislocations and surfaces of layers formed over substrates, as well as placement of misfit dislocations and dislocation arrays with respect to devices subsequently formed on the layers.
    Type: Application
    Filed: July 29, 2003
    Publication date: June 17, 2004
    Applicant: AmberWave Systems Corporation
    Inventors: Anthony J. Lochtefeld, Christopher W. Leitz, Matthew T. Currie, Mayank Bulsara
  • Patent number: 6730551
    Abstract: A structure and a method for forming the structure, the method including forming a compressively strained semiconductor layer, the compressively strained layer having a strain greater than or equal to 0.25%. A tensilely strained semiconductor layer is formed over the compressively strained layer. The compressively strained layer is substantially planar, having a surface roughness characterized in (i) having an average wavelength greater than an average wavelength of a carrier in the compressively strained layer or (ii) having an average height less than 10 nm.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: May 4, 2004
    Assignee: Massachusetts Institute of Technology
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Publication number: 20040026765
    Abstract: A semiconductor structure includes a strain-inducing substrate layer having a germanium concentration of at least 10 atomic %. The semiconductor structure also includes a compressively strained layer on the strain-inducing substrate layer. The compressively strained layer has a germanium concentration at least approximately 30 percentage points greater than the germanium concentration of the strain-inducing substrate layer, and has a thickness less than its critical thickness. The semiconductor structure also includes a tensilely strained layer on the compressively strained layer. The tensilely strained layer may be formed from silicon having a thickness less than its critical thickness.
    Type: Application
    Filed: June 6, 2003
    Publication date: February 12, 2004
    Applicant: AmberWave Systems Corporation
    Inventors: Matthew T. Currie, Anthony J. Lochtefeld, Christopher W. Leitz, Eugene A. Fitzgerald
  • Publication number: 20030052334
    Abstract: The invention provides semiconductor structure comprising a strained Ge channel layer, and a gate dielectric disposed over the strained Ge channel layer. In one aspect of the invention, a strained Ge channel MOSFET is provided. The strained Ge channel MOSFET includes a relaxed SiGe virtual substrate with a Ge content between 50-95%, and a strained Ge channel formed on the virtual substrate. A gate structure is formed upon the strained Ge channel, whereupon a MOSFET is formed with increased performance over bulk Si. In another embodiment of the invention, a semiconductor structure comprising a relaxed Ge channel layer and a virtual substrate, wherein the relaxed Ge channel layer is disposed above the virtual substrate. In a further aspect of the invention, a relaxed Ge channel MOSFET is provided. The method includes providing a relaxed virtual substrate with a Ge composition of approximately 100% and a relaxed Ge channel formed on the virtual substrate.
    Type: Application
    Filed: June 18, 2002
    Publication date: March 20, 2003
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Publication number: 20030025131
    Abstract: A structure and a method for forming the structure, the method including forming a compressively strained semiconductor layer, the compressively strained layer having a strain greater than or equal to 0.25%. A tensilely strained semiconductor layer is formed over the compressively strained layer. The compressively strained layer is substantially planar, having a surface roughness characterized in (i) having an average wavelength greater than an average wavelength of a carrier in the compressively strained layer or (ii) having an average height less than 10 nm.
    Type: Application
    Filed: August 2, 2002
    Publication date: February 6, 2003
    Applicant: Massachusetts Institute of Technology
    Inventors: Minjoo L. Lee, Christopher W. Leitz, Eugene A. Fitzgerald
  • Publication number: 20020197803
    Abstract: A structure includes a tensile strained layer disposed over a substrate, the tensile strained layer having a first thickness. A compressed layer is disposed between the tensile strained layer and the substrate, the compressed layer having a second thickness. The first and second thicknesses are selected to define a first carrier mobility in the tensile strained layer and a second carrier mobility in the compressed layer.
    Type: Application
    Filed: June 21, 2002
    Publication date: December 26, 2002
    Applicant: AmberWave Systems Corporation
    Inventors: Christopher W. Leitz, Minjoo L. Lee, Eugene A. Fitzgerald