Patents by Inventor David H. Wells

David H. Wells 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: 7906830
    Abstract: Memory cell structures, including PSOIs, NANDs, NORs, FinFETs, etc., and methods of fabrication have been described that include a method of epitaxial silicon growth. The method includes providing a silicon layer on a substrate. A dielectric layer is provided on the silicon layer. A trench is formed in the dielectric layer to expose the silicon layer, the trench having trench walls in the <100> direction. The method includes epitaxially growing silicon between trench walls formed in the dielectric layer.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: March 15, 2011
    Assignee: Micron Technology, Inc.
    Inventors: David H. Wells, Du Li
  • Publication number: 20100321988
    Abstract: Memory devices comprise a plurality of memory cells, each memory cell including a memory element and a selection device. A plurality of first (e.g., row) address lines can be adjacent (e.g., under) a first side of at least some cells of the plurality. A plurality of second (e.g., column) address lines extend across the plurality of row address lines, each column address line being adjacent (e.g., over) a second, opposing side of at least some of the cells. Control circuitry can be configured to selectively apply a read voltage or a write voltage substantially simultaneously to the address lines. Systems including such memory devices and methods of accessing a plurality of cells at least substantially simultaneously are also disclosed.
    Type: Application
    Filed: June 23, 2009
    Publication date: December 23, 2010
    Applicant: Micron Technology, Inc.
    Inventors: David H. Wells, Jun Liu
  • Publication number: 20100308438
    Abstract: A method for fabricating semiconductor device structures includes forming a non-conformal mask over a surface of a substrate. Non-conformal mask material with a planar or substantially planar upper surface is formed on the surface of the substrate. The planarity or substantial planarity of the non-conformal material eliminates or substantially eliminates distortion in a “mask” formed thereover and, thus, eliminates or substantially eliminates distortion in any mask that is subsequently formed using the pattern of the mask. In some embodiments, mask material of the non-conformal mask does not extend into recesses in the upper surface of the substrate; instead it “bridges” the recesses. Semiconductor device structures that include non-conformal masks and semiconductor device structures that have been fabricated with non-conformal masks are also disclosed.
    Type: Application
    Filed: June 3, 2009
    Publication date: December 9, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventor: David H. Wells
  • Publication number: 20100291742
    Abstract: A method of fabricating a memory cell comprises forming a plurality of doped semiconductor layers on a carrier substrate. The method further comprises forming a plurality of digit lines separated by an insulating material. The digit lines are arrayed over the doped semiconductor layers. The method further comprises etching a plurality of trenches into the doped semiconductor layers. The method further comprises depositing an insulating material into the plurality of trenches to form a plurality of electrically isolated transistor pillars. The method further comprises bonding at least a portion of the structure formed on the carrier substrate to a host substrate. The method further comprises separating the carrier substrate from the host substrate.
    Type: Application
    Filed: July 27, 2010
    Publication date: November 18, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: David H. Wells, H. Montgomery Manning
  • Publication number: 20100290268
    Abstract: A memory cell, device, and system include a memory cell having a shared digitline, a storage capacitor, and a plurality of access transistors configured to selectively electrically couple the storage capacitor with the shared digitline. The digitline couples with adjacent memory cells and the plurality of access transistor selects which adjacent memory cell is coupled to the shared digitline. A method of forming the memory cell includes forming a buried digitline in the substrate and a vertical pillar in the substrate immediately adjacent to the buried digitline. A dual gate transistor is formed on the vertical pillar with a first end electrically coupled to the buried digitline and a second end coupled to a storage capacitor formed thereto.
    Type: Application
    Filed: July 27, 2010
    Publication date: November 18, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: H. Montgomery Manning, David H. Wells
  • Publication number: 20100276741
    Abstract: A method of forming a buried digit line is disclosed. Sacrificial spacers are formed along the sidewalls of an isolation trench, which is then filled with a sacrificial material. One spacer is masked while the other spacer is removed and an etch step into the substrate beneath the removed spacer forms an isolation window. Insulating liners are then formed along the sidewalls of the emptied trench, including into the isolation window. A digit line recess is then formed through the bottom of the trench between the insulating liners, which double as masks to self-align this etch. The digit line recess is then filled with metal and recessed back, with an optional prior insulating element deposited and recessed back in the bottom of the recess.
    Type: Application
    Filed: July 14, 2010
    Publication date: November 4, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventor: David H. Wells
  • Patent number: 7786522
    Abstract: A memory cell, device, and system include a memory cell having a shared digitline, a storage capacitor, and a plurality of access transistors configured to selectively electrically couple the storage capacitor with the shared digitline. The digitline couples with adjacent memory cells and the plurality of access transistor selects which adjacent memory cell is coupled to the shared digitline. A method of forming the memory cell includes forming a buried digitline in the substrate and a vertical pillar in the substrate immediately adjacent to the buried digitline. A dual gate transistor is formed on the vertical pillar with a first end electrically coupled to the buried digitline and a second end coupled to a storage capacitor formed thereto.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: August 31, 2010
    Assignee: Micron Technology, Inc.
    Inventors: H. Montgomery Manning, David H. Wells
  • Patent number: 7776715
    Abstract: A method of fabricating a memory cell comprises forming a plurality of doped semiconductor layers on a carrier substrate. The method further comprises forming a plurality of digit lines separated by an insulating material. The digit lines are arrayed over the doped semiconductor layers. The method further comprises etching a plurality of trenches into the doped semiconductor layers. The method further comprises depositing an insulating material into the plurality of trenches to form a plurality of electrically isolated transistor pillars. The method further comprises bonding at least a portion of the structure formed on the carrier substrate to a host substrate. The method further comprises separating the carrier substrate from the host substrate.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: August 17, 2010
    Assignee: Micron Technology, Inc.
    Inventors: David H. Wells, H. Montgomery Manning
  • Patent number: 7768073
    Abstract: A method of forming a buried digit line is disclosed. Sacrificial spacers are formed along the sidewalls of an isolation trench, which is then filled with a sacrificial material. One spacer is masked while the other spacer is removed and an etch step into the substrate beneath the removed spacer forms an isolation window. Insulating liners are then formed along the sidewalls of the emptied trench, including into the isolation window. A digit line recess is then formed through the bottom of the trench between the insulating liners, which double as masks to self-align this etch. The digit line recess is then filled with metal and recessed back, with an optional prior insulating element deposited and recessed back in the bottom of the recess.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: August 3, 2010
    Assignee: Micron Technology, Inc.
    Inventor: David H. Wells
  • Publication number: 20100171176
    Abstract: Some embodiments include methods of forming voids within semiconductor constructions. In some embodiments the voids may be utilized as microstructures for distributing coolant, for guiding electromagnetic radiation, or for separation and/or characterization of materials. Some embodiments include constructions having micro-structures therein which correspond to voids, conduits, insulative structures, semiconductor structures or conductive structures.
    Type: Application
    Filed: March 17, 2010
    Publication date: July 8, 2010
    Applicant: Micron Technology, Inc.
    Inventor: David H. Wells
  • Patent number: 7749786
    Abstract: Some embodiments include methods of forming voids within semiconductor constructions. In some embodiments the voids may be utilized as microstructures for distributing coolant, for guiding electromagnetic radiation, or for separation and/or characterization of materials. Some embodiments include constructions having micro-structures therein which correspond to voids, conduits, insulative structures, semiconductor structures or conductive structures.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: July 6, 2010
    Assignee: Micron Technology, Inc.
    Inventor: David H. Wells
  • Publication number: 20100109120
    Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The single crystal silicon substrate is exposed to an anisotropic etchant that undercuts the single crystal silicon. By controlling the length of the etch, single crystal silicon islands or smooth vertical walls in the single crystal silicon may be created.
    Type: Application
    Filed: January 14, 2010
    Publication date: May 6, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Janos Fucsko, David H. Wells, Patrick Flynn, Whonchee Lee
  • Patent number: 7709327
    Abstract: Some embodiments include methods of forming voids within semiconductor constructions. In some embodiments the voids may be utilized as microstructures for distributing coolant, for guiding electromagnetic radiation, or for separation and/or characterization of materials. Some embodiments include constructions having micro-structures therein which correspond to voids, conduits, insulative structures, semiconductor structures or conductive structures.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: May 4, 2010
    Assignee: Micron Technology, Inc.
    Inventor: David H. Wells
  • Patent number: 7709341
    Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The single crystal silicon substrate is exposed to an anisotropic etchant that undercuts the single crystal silicon. By controlling the length of the etch, single crystal silicon islands or smooth vertical walls in the single crystal silicon may be created.
    Type: Grant
    Filed: June 2, 2006
    Date of Patent: May 4, 2010
    Assignee: Micron Technology, Inc.
    Inventors: Janos Fucsko, David H. Wells, Patrick Flynn, Whonchee Lee
  • Publication number: 20100065941
    Abstract: An intermediate semiconductor structure that comprises a substrate and at least one undercut structure formed in the substrate is disclosed. The undercut feature may include a vertical opening having a lateral cavity therein, the vertical opening extending below the lateral cavity. The lateral cavity may include faceted sidewalls.
    Type: Application
    Filed: November 20, 2009
    Publication date: March 18, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: David H. Wells, H. Montgomery Manning
  • Publication number: 20100029081
    Abstract: Single spacer processes for multiplying pitch by a factor greater than two are provided. In one embodiment, n, where n?2, tiers of stacked mandrels are formed over a substrate, each of the n tiers comprising a plurality of mandrels substantially parallel to one another. Mandrels at tier n are over and parallel to mandrels at tier n?1, and the distance between adjoining mandrels at tier n is greater than the distance between adjoining mandrels at tier n?1. Spacers are simultaneously formed on sidewalls of the mandrels. Exposed portions of the mandrels are etched away and a pattern of lines defined by the spacers is transferred to the substrate.
    Type: Application
    Filed: October 12, 2009
    Publication date: February 4, 2010
    Applicant: Micron Technology, Inc.
    Inventors: David H. Wells, Mirzafer K. Abatchev
  • Publication number: 20100013061
    Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The substrate is exposed to a buffered fluoride etch solution which undercuts the silicon to provide lateral shelves when patterned in the <100> direction. The resulting structure includes an undercut feature when patterned in the <100> direction.
    Type: Application
    Filed: September 23, 2009
    Publication date: January 21, 2010
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Whonchee Lee, Janos Fucsko, David H. Wells
  • Patent number: 7628932
    Abstract: A single crystal silicon etching method includes providing a single crystal silicon substrate having at least one trench therein. The substrate is exposed to a buffered fluoride etch solution which undercuts the silicon to provide lateral shelves when patterned in the <100> direction. The resulting structure includes an undercut feature when patterned in the <100> direction.
    Type: Grant
    Filed: June 2, 2006
    Date of Patent: December 8, 2009
    Assignee: Micron Technology, Inc.
    Inventors: Whonchee Lee, Janos Fucsko, David H. Wells
  • Patent number: 7625776
    Abstract: A method of forming at least one undercut structure in a semiconductor substrate. The method comprises providing a semiconductor substrate, forming at least one doped region in the semiconductor substrate, and removing the at least one doped region to form at least one undercut structure in the semiconductor substrate. The at least one undercut structure may include at least one substantially vertical shelf, at least one substantially horizontal shelf, and at least one faceted surface. The at least one doped region may be formed by implanting an impurity in the semiconductor substrate, which is, optionally, annealed. The at least one doped region may be removed selective to the undoped portion of the semiconductor substrate by at least one of wet etching or dry etching. An intermediate semiconductor structure that comprises a single crystalline silicon substrate and at least one undercut structure formed in the single crystalline silicon substrate is also disclosed.
    Type: Grant
    Filed: June 2, 2006
    Date of Patent: December 1, 2009
    Assignee: Micron Technology, Inc.
    Inventors: David H. Wells, H. Montgomery Manning
  • Patent number: 7611980
    Abstract: Single spacer processes for multiplying pitch by a factor greater than two are provided. In one embodiment, n, where n?2, tiers of stacked mandrels are formed over a substrate, each of the n tiers comprising a plurality of mandrels substantially parallel to one another. Mandrels at tier n are over and parallel to mandrels at tier n?1, and the distance between adjoining mandrels at tier n is greater than the distance between adjoining mandrels at tier n?1. Spacers are simultaneously formed on sidewalls of the mandrels. Exposed portions of the mandrels are etched away and a pattern of lines defined by the spacers is transferred to the substrate.
    Type: Grant
    Filed: August 30, 2006
    Date of Patent: November 3, 2009
    Assignee: Micron Technology, Inc.
    Inventors: David H. Wells, Mirzafer K. Abatchev