Patents by Inventor Judy L. Hoyt

Judy L. Hoyt 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: 9269633
    Abstract: Semiconductor device performance is improved via a gate structure having a tunable effective workfunction and reduced gate depletion effects. According to an example embodiment, the design threshold voltage of a semiconductor device is adjusted in a manner that includes providing a gate having a workfunction that enables operation of the semiconductor device at a selected voltage. The gate is formed having two different conductive materials with different electric workfunctions that both significantly contribute to the overall workfunction of the gate. The relative composition, thickness, and arrangement of each of the two conductive materials is selected to attain a gate electrode workfunction that is different than the workfunctions of each of the two layers and that sets the threshold voltage of the semiconductor device. The adjustability of the effective workfunction of the gate electrode can be applied to a variety of semiconductor devices.
    Type: Grant
    Filed: May 23, 2014
    Date of Patent: February 23, 2016
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Steven Hung, Judy L. Hoyt, James F. Gibbons
  • Publication number: 20140329378
    Abstract: Semiconductor device performance is improved via a gate structure having a tunable effective workfunction and reduced gate depletion effects. According to an example embodiment, the design threshold voltage of a semiconductor device is adjusted in a manner that includes providing a gate having a workfunction that enables operation of the semiconductor device at a selected voltage. The gate is formed having two different conductive materials with different electric workfunctions that both significantly contribute to the overall workfunction of the gate. The relative composition, thickness, and arrangement of each of the two conductive materials is selected to attain a gate electrode workfunction that is different than the workfunctions of each of the two layers and that sets the threshold voltage of the semiconductor device. The adjustability of the effective workfunction of the gate electrode can be applied to a variety of semiconductor devices.
    Type: Application
    Filed: May 23, 2014
    Publication date: November 6, 2014
    Applicant: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Steven Hung, Judy L. Hoyt, James F. Gibbons
  • Patent number: 7920770
    Abstract: Structures including optical waveguides disposed over substrates having a chamber or trench defined therein, and methods for formation thereof.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: April 5, 2011
    Assignee: Massachusetts Institute of Technology
    Inventors: Charles Holzwarth, Jason S. Orcutt, Milos Popovic, Judy L. Hoyt, Rajeev Ram
  • Patent number: 7867859
    Abstract: Semiconductor device performance is improved via a gate structure having a tunable effective workfunction and reduced gate depletion effects. According to an example embodiment, the design threshold voltage of a semiconductor device is adjusted in a manner that includes providing a gate having a workfunction that enables operation of the semiconductor device at a selected voltage. The gate is formed having two different conductive materials with different electric workfunctions that both significantly contribute to the overall workfunction of the gate. The relative composition, thickness, and arrangement of each of the two conductive materials is selected to attain a gate electrode workfunction that is different than the workfunctions of each of the two layers and that sets the threshold voltage of the semiconductor device. The adjustability of the effective workfunction of the gate electrode can be applied to a variety of semiconductor devices.
    Type: Grant
    Filed: June 17, 2008
    Date of Patent: January 11, 2011
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Steven Hung, Judy L. Hoyt, James F. Gibbons
  • Publication number: 20090274418
    Abstract: Structures including optical waveguides disposed over substrates having a chamber or trench defined therein, and methods for formation thereof.
    Type: Application
    Filed: May 1, 2008
    Publication date: November 5, 2009
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Charles Holzwarth, Jason S. Orcutt, Milos Popovic, Judy L. Hoyt, Rajeev Ram
  • Publication number: 20090072271
    Abstract: Disclosed is a method of growing thin and smooth germanium (Ge) on a strained or relaxed silicon (Si) layer comprising the steps of: (a) treating surface of the strained or relaxed Si layer to gaseous precursors of both Si (e.g., silane) and Ge (e.g., germane) for a predetermined short time duration ?t, where 1??t?30 seconds; and (b) depositing a thin Ge film on top of said treated Si layer, wherein said treatment step of (a) reduces growth time and surface roughness of the thin Ge film (e.g., sub-5 nm or sub-20 nm thick) deposited on the Si layer. The treatment step (a) can be conducted at a steady predetermined temperature T, where 450?T?900° C. The predetermined short time duration ?t can be chosen such that less than 10 A of SiGe is deposited.
    Type: Application
    Filed: September 18, 2008
    Publication date: March 19, 2009
    Inventors: Leonardo Gomez, Meekyung Kim, Judy L. Hoyt
  • Patent number: 6921914
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1-xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1-yGey layer, a thin strained Si1-zGez layer and another relaxed Si1-yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1-yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1-yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1-xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects. Hydrogen ions are introduced into the relaxed GaAs layer at the selected depth.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: July 26, 2005
    Assignee: Massachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Publication number: 20040173791
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1-xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1-yGey layer, a thin strained Si1-zGez layer and another relaxed Si1-yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1-yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1-yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1-xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects. Hydrogen ions are introduced into the relaxed GaAs layer at the selected depth.
    Type: Application
    Filed: March 17, 2004
    Publication date: September 9, 2004
    Applicant: Massachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Publication number: 20040113211
    Abstract: Semiconductor device (100) performance is improved via a gate structure (120) having a tunable effective workfunction and reduced gate depletion effects. According to an example embodiment of the present invention, the design threshold voltage of a semiconductor device (100) is adjusted in a manner that includes providing a gate having a workfunction that enables operation of the semiconductor device (100) at a selected voltage. The gate is formed having two different conductive materials (130, 135) with different electric workfunctions that both significantly contribute to the overall workfunction of the gate. The relative composition, thickness, and arrangement of each of the two conductive material is selected to attain a gate electrode workfunction that is different than the workfunctions of each of the two layers and that sets the threshold voltage of the semiconductor device (100). In addition, by selecting the order of the layers, carrier depletion in the gate electrode can be avoided.
    Type: Application
    Filed: January 16, 2004
    Publication date: June 17, 2004
    Inventors: Steven Hung, Judy L Hoyt, James F Gibbons
  • Patent number: 6737670
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1−xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1−yGey layer, a thin strained Si1−zGez layer and another relaxed Si1−yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1−yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1−yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1−xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: May 18, 2004
    Assignee: Massachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Patent number: 6713326
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1−xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1−yGey layer, a thin strained Si1−zGez layer and another relaxed Si1−yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1−yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1−yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1−xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects.
    Type: Grant
    Filed: March 4, 2003
    Date of Patent: March 30, 2004
    Assignee: Masachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Publication number: 20030168654
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1−xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1−yGey layer, a thin strained Si1−zGez layer and another relaxed Si1−yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1−yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1−yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1−xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects.
    Type: Application
    Filed: March 7, 2003
    Publication date: September 11, 2003
    Applicant: Massachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Publication number: 20030155568
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1−xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1−yGey layer, a thin strained Si1−zGez layer and another relaxed Si1−yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1−yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1−yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1−xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects.
    Type: Application
    Filed: March 4, 2003
    Publication date: August 21, 2003
    Applicant: Massachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Patent number: 6573126
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1−xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1−yGey layer, a thin strained Si1−zGez layer and another relaxed Si1−yGey layer. Hydrogen ions are then introduced into the strained SizGez layer. The relaxed Si1−yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1−yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1−xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: June 3, 2003
    Assignee: Massachusetts Institute of Technology
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Publication number: 20020072130
    Abstract: A process for producing monocrystalline semiconductor layers. In an exemplary embodiment, a graded Si1-xGex (x increases from 0 to y) is deposited on a first silicon substrate, followed by deposition of a relaxed Si1-yGey layer, a thin strained Si1-zGez layer and another relaxed Si1-yGey layer. Hydrogen ions are then introduced into the strained SizGz layer. The relaxed Si1-yGey layer is bonded to a second oxidized substrate. An annealing treatment splits the bonded pair at the strained Si layer, such that the second relaxed Si1-yGey layer remains on the second substrate. In another exemplary embodiment, a graded Si1-xGex is deposited on a first silicon substrate, where the Ge concentration x is increased from 0 to 1. Then a relaxed GaAs layer is deposited on the relaxed Ge buffer. As the lattice constant of GaAs is close to that of Ge, GaAs has high quality with limited dislocation defects. Hydrogen ions are introduced into the relaxed GaAs layer at the selected depth.
    Type: Application
    Filed: August 10, 2001
    Publication date: June 13, 2002
    Inventors: Zhi-Yuan Cheng, Eugene A. Fitzgerald, Dimitri A. Antoniadis, Judy L. Hoyt
  • Patent number: 5256550
    Abstract: The present invention comprises a method of fabricating devices and circuits employing at least one heteroepitaxial layer under strain. The thickness of the heteroepitaxial layer is more than two times the calculated equilibrium critical thickness for an uncapped heteroepitaxial layer upon a crystalline substrate, based on previously known equilibrium theory for the uncapped layer. Subsequent to growth of the heteroepitaxial layer, the structure is processed at temperatures higher than the growth temperature of the heteroepitaxial layer.The strained heteroepitaxial layer (second layer) is epitaxially grown upon the surface of a first, underlaying crystalline layer, creating a heterojunction. Subsequently a third crystalline layer is deposited or grown upon the major exposed surface of the second, strained heteroepitaxial layer. The preferred manner of growth of the third crystalline layer is epitaxial growth.
    Type: Grant
    Filed: June 12, 1991
    Date of Patent: October 26, 1993
    Assignee: Hewlett-Packard Company
    Inventors: Stephen Laderman, Martin Scott, Theodore I. Kamins, Judy L. Hoyt, Clifford A. King, James F. Gibbons, David B. Noble
  • Patent number: 5202284
    Abstract: Several methods are disclosed for minimizing the number of defects or misfit locations in a SiGe layer selectively or non-selectively deposited on a partially oxide masked Si substrate.
    Type: Grant
    Filed: December 1, 1989
    Date of Patent: April 13, 1993
    Assignee: Hewlett-Packard Company
    Inventors: Theodore I. Kamins, David B. Noble, Judy L. Hoyt, James F. Gibbons, Martin P. Scott
  • Patent number: 5084411
    Abstract: Improved devices with silicon to SiGe alloy heterojunctions are provided for in accordance with the following discoveries. X-ray topography and transmission electron microscopy were used to quantify misfit-dislocation spacings in as-grown Si.sub.1-x Ge.sub.x films formed by Limited Reaction Processing (LRP), which is a chemical vapor deposition technique. These analysis techniques were also used to study dislocation formation during annealing of material grown by both LRP and by molecular beam epitaxy (MBE). The thickness at which misfit dislocations first appear in as-grown material was similar for both growth techniques. The thermal stability of capped and uncapped films was also investigated after rapid thermal annealing in the range of 625.degree. to 1000.degree. C. Significantly fewer misfit dislocations were observed in samples containing an epitaxial silicon cap.
    Type: Grant
    Filed: November 29, 1988
    Date of Patent: January 28, 1992
    Assignee: Hewlett-Packard Company
    Inventors: Stephen Laderman, Martin Scott, Theodore I. Kamins, Judy L. Hoyt, Clifford A. King, James F. Gibbons, David B. Noble
  • Patent number: 4787551
    Abstract: Disclosed is a method of welding a temperature-sensing thermocouple to a silicon wafer for sensing the temperature of the wafer during rapid thermal processing using TIG welding and/or electron-beam welding. In one embodiment, a ball of silicon is formed on the bead at one end of a thermocouple by placing the thermocouple on a silicon chip and then melting the silicon chip with a TIG welder. The ball and thermocouple are then placed on the surface of a silicon wafer and the ball and surface are then melted whereby the ball of silicon flows into the silicon wafer. In placing the thermocouple on an edge portion of a silicon wafer, the wafer is supported on a tantalum plate with the edge portion of the wafer extending beyond the plate. A molybdenum sheet is positioned on the top surface of the wafer with the edge portion of the wafer exposed. A TIG arc is established with the molybdenum layer and then the arc is moved to the edge portion of the wafer for melting the silicon.
    Type: Grant
    Filed: May 4, 1987
    Date of Patent: November 29, 1988
    Assignee: Stanford University
    Inventors: Judy L. Hoyt, Kenneth E. Williams, James F. Gibbons