Patents by Inventor Fawad Ahmed

Fawad Ahmed 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: 9263341
    Abstract: Some embodiments include methods of forming transistors. Recesses are formed to extend into semiconductor material. The recesses have upper regions lined with liner material and have segments of semiconductor material exposed along lower regions. Semiconductor material is isotropically etched through the exposed segments which transforms the recesses into openings having wide lower regions beneath narrow upper regions. Gate dielectric material is formed along sidewalls of the openings. Gate material is formed within the openings and over regions of the semiconductor material between the openings. Insulative material is formed down the center of each opening and entirely through the gate material. A segment of gate material extends from one of the openings to the other, and wraps around a pillar of the semiconductor material between the openings. The segment is a gate of a transistor. Source/drain regions are formed on opposing sides of the gate.
    Type: Grant
    Filed: August 26, 2015
    Date of Patent: February 16, 2016
    Assignee: Micron Technology, Inc.
    Inventors: Deepak Chandra Pandey, Haitao Liu, Fawad Ahmed, Kamal M. Karda
  • Publication number: 20150364377
    Abstract: Some embodiments include methods of forming transistors. Recesses are formed to extend into semiconductor material. The recesses have upper regions lined with liner material and have segments of semiconductor material exposed along lower regions. Semiconductor material is isotropically etched through the exposed segments which transforms the recesses into openings having wide lower regions beneath narrow upper regions. Gate dielectric material is formed along sidewalls of the openings. Gate material is formed within the openings and over regions of the semiconductor material between the openings. Insulative material is formed down the center of each opening and entirely through the gate material. A segment of gate material extends from one of the openings to the other, and wraps around a pillar of the semiconductor material between the openings. The segment is a gate of a transistor. Source/drain regions are formed on opposing sides of the gate.
    Type: Application
    Filed: August 26, 2015
    Publication date: December 17, 2015
    Inventors: Deepak Chandra Pandey, Haitao Liu, Fawad Ahmed, Kamal M. Karda
  • Publication number: 20150279694
    Abstract: Some embodiments include methods of forming silicon dioxide in which silicon dioxide is formed across silicon utilizing a first treatment temperature of no greater than about 1000° C., and in which an interface between the silicon dioxide and the silicon is annealed utilizing a second treatment temperature which is at least about 1050° C. Some embodiments include methods of forming transistors in which a trench is formed to extend into monocrystalline silicon. Silicon dioxide is formed along multiple crystallographic planes along an interior of the trench utilizing a first treatment temperature of no greater than about 1000° C., and an interface between the silicon dioxide and the monocrystalline silicon is annealed utilizing a second treatment temperature which is at least about 1050° C. A transistor gate is formed within the trench, and a pair of source/drain regions is formed within the monocrystalline silicon adjacent the transistor gate. Some embodiments include DRAM cells.
    Type: Application
    Filed: June 15, 2015
    Publication date: October 1, 2015
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Shivani Srivastava, Kunal Shrotri, Fawad Ahmed
  • Patent number: 9147729
    Abstract: Some embodiments include methods of forming transistors. Recesses are formed to extend into semiconductor material. The recesses have upper regions lined with liner material and have segments of semiconductor material exposed along lower regions. Semiconductor material is isotropically etched through the exposed segments which transforms the recesses into openings having wide lower regions beneath narrow upper regions. Gate dielectric material is formed along sidewalls of the openings. Gate material is formed within the openings and over regions of the semiconductor material between the openings. Insulative material is formed down the center of each opening and entirely through the gate material. A segment of gate material extends from one of the openings to the other, and wraps around a pillar of the semiconductor material between the openings. The segment is a gate of a transistor. Source/drain regions are formed on opposing sides of the gate.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: September 29, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Deepak Pandey, Haitao Liu, Fawad Ahmed, Kamal M. Karda
  • Publication number: 20150243734
    Abstract: Some embodiments include methods of forming transistors. Recesses are formed to extend into semiconductor material. The recesses have upper regions lined with liner material and have segments of semiconductor material exposed along lower regions. Semiconductor material is isotropically etched through the exposed segments which transforms the recesses into openings having wide lower regions beneath narrow upper regions. Gate dielectric material is formed along sidewalls of the openings. Gate material is formed within the openings and over regions of the semiconductor material between the openings. Insulative material is formed down the center of each opening and entirely through the gate material. A segment of gate material extends from one of the openings to the other, and wraps around a pillar of the semiconductor material between the openings. The segment is a gate of a transistor. Source/drain regions are formed on opposing sides of the gate.
    Type: Application
    Filed: February 25, 2014
    Publication date: August 27, 2015
    Applicant: Micron Technology, Inc.
    Inventors: Deepak Pandey, Haitao Liu, Fawad Ahmed, Kamal M. Karda
  • Patent number: 9064692
    Abstract: Some embodiments include methods of forming silicon dioxide in which silicon dioxide is formed across silicon utilizing a first treatment temperature of no greater than about 1000° C., and in which an interface between the silicon dioxide and the silicon is annealed utilizing a second treatment temperature which is at least about 1050° C. Some embodiments include methods of forming transistors in which a trench is formed to extend into monocrystalline silicon. Silicon dioxide is formed along multiple crystallographic planes along an interior of the trench utilizing a first treatment temperature of no greater than about 1000° C., and an interface between the silicon dioxide and the monocrystalline silicon is annealed utilizing a second treatment temperature which is at least about 1050° C. A transistor gate is formed within the trench, and a pair of source/drain regions is formed within the monocrystalline silicon adjacent the transistor gate. Some embodiments include DRAM cells.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: June 23, 2015
    Assignee: Micron Technology, Inc.
    Inventors: Shivani Srivastava, Kunal Shrotri, Fawad Ahmed
  • Publication number: 20130277723
    Abstract: Some embodiments include methods of forming silicon dioxide in which silicon dioxide is formed across silicon utilizing a first treatment temperature of no greater than about 1000° C., and in which an interface between the silicon dioxide and the silicon is annealed utilizing a second treatment temperature which is at least about 1050° C. Some embodiments include methods of forming transistors in which a trench is formed to extend into monocrystalline silicon. Silicon dioxide is formed along multiple crystallographic planes along an interior of the trench utilizing a first treatment temperature of no greater than about 1000° C., and an interface between the silicon dioxide and the monocrystalline silicon is annealed utilizing a second treatment temperature which is at least about 1050° C. A transistor gate is formed within the trench, and a pair of source/drain regions is formed within the monocrystalline silicon adjacent the transistor gate. Some embodiments include DRAM cells.
    Type: Application
    Filed: April 19, 2012
    Publication date: October 24, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventors: Shivani Srivastava, Kunal Shrotri, Fawad Ahmed
  • Patent number: 7119397
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: October 10, 2006
    Assignee: Micron Technology, Inc.
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Publication number: 20050181567
    Abstract: A double blanket ion implant method for forming diffulsion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface Next, a first pair of diffulsion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Application
    Filed: March 31, 2005
    Publication date: August 18, 2005
    Inventors: Mark Fischer, Charles Dennison, Fawad Ahmed, Richard Lane, John Zahurak, Kunal Parekh
  • Patent number: 6797596
    Abstract: A method used during the formation of a semiconductor device reduces ion channeling during implantation of the wafer. The method comprises providing a semiconductor wafer and an unetched transistor gate stack assembly over the wafer. The unetched transistor gate stack assembly comprises a gate oxide layer, a control gate layer, a metal layer, and a dielectric capping layer. A patterned photoresist layer is formed over the unetched transistor gate stack assembly, then each of the capping layer, the metal layer, the control gate layer, and the gate oxide layer is etched to form a plurality of laterally-spaced transistor gate stacks. A screening layer is formed overlying the semiconductor wafer between the transistor gate stacks. A dopant is implanted into the semiconductor wafer through the screening layer, then the screening layer is removed.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: September 28, 2004
    Assignee: Micron Technology, Inc.
    Inventors: Fawad Ahmed, Jigish D. Trivedi, Suraj J Mathew
  • Publication number: 20040150035
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Application
    Filed: February 2, 2004
    Publication date: August 5, 2004
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Publication number: 20040043586
    Abstract: A method used during the formation of a semiconductor device reduces ion channeling during implantation of the wafer. The method comprises providing a semiconductor wafer and an unetched transistor gate stack assembly over the wafer. The unetched transistor gate stack assembly comprises a gate oxide layer, a control gate layer, a metal layer, and a dielectric capping layer. A patterned photoresist layer is formed over the unetched transistor gate stack assembly, then each of the capping layer, the metal layer, the control gate layer, and the gate oxide layer is etched to form a plurality of laterally-spaced transistor gate stacks. A screening layer is formed overlying the semiconductor wafer between the transistor gate stacks. A dopant is implanted into the semiconductor wafer through the screening layer, then the screening layer is removed.
    Type: Application
    Filed: August 29, 2002
    Publication date: March 4, 2004
    Inventors: Fawad Ahmed, Jigish D. Trivedi, Suraj J. Mathew
  • Patent number: 6693014
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface. Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: February 17, 2004
    Assignee: Micron Technology, Inc.
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Publication number: 20030054603
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Application
    Filed: November 1, 2002
    Publication date: March 20, 2003
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Patent number: 6482707
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Grant
    Filed: March 21, 2000
    Date of Patent: November 19, 2002
    Assignee: Micron Technology, Inc.
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Patent number: 6410951
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface. Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Grant
    Filed: April 2, 2001
    Date of Patent: June 25, 2002
    Assignee: Micron Technology, Inc.
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Publication number: 20010023948
    Abstract: A double blanket ion implant method for forming diffusion regions in memory array devices, such as a MOSFET access device is disclosed. The method provides a semiconductor substrate with a gate structure formed on its surface Next, a first pair of diffusion regions are formed in a region adjacent to the channel region by a first blanket ion implantation process. The first blanket ion implantation process has a first energy level and dose. The device is subjected to oxidizing conditions, which form oxidized sidewalls on the gate structure. A second blanket ion implantation process is conducted at the same location as the first ion implantation process adding additional dopant to the diffusion regions. The second blanket ion implantation process has a second energy level and dose. The resultant diffusion regions provide the device with improved static refresh performance over prior art devices.
    Type: Application
    Filed: April 2, 2001
    Publication date: September 27, 2001
    Inventors: Mark Fischer, Charles H. Dennison, Fawad Ahmed, Richard H. Lane, John K. Zahurak, Kunal R. Parekh
  • Patent number: 6187618
    Abstract: An SRAM memory cell is provided in which a pair of cross-coupled n-type MOS pull-down transistors are coupled to respective parasitically formed bipolar pull-up transistors. The memory cell is formed within a semiconductor layer which extends over a buried layer. The bipolar transistors are formed parasitically from the buried layer and the semiconductor layer used to form the pull-down transistors. The bases of the bipolar transistors may also be dynamically controlled. An SRAM memory array having a plurality of such memory cells and a computer system incorporating the SRAM memory array are also provided.
    Type: Grant
    Filed: February 12, 1999
    Date of Patent: February 13, 2001
    Assignee: Micron Technology, Inc.
    Inventors: David A. Kao, Fawad Ahmed
  • Patent number: 6040208
    Abstract: A method of implanting dopants within an exposed first active region on a semiconductor substrate of a semiconductor wafer without doping an exposed second active region of the semiconductor substrate. A barrier wall is formed adjacent to the second active region and projects from the semiconductor substrate to a height above the second active region. A minimal angle relative to an axis perpendicular to the semiconductor substrate is determined at which doping ions directed at the semiconductor substrate must travel so that the barrier wall blocks the doping ions from contacting the second active region. The doping ions are used to bombard the semiconductor substrate at an angle at least as large as the minimal angle previously determined. As a result, the doping ions contact the first active region but do not substantially contact the second active region. The width of the second active region can be formed as greater than that of the first active.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: March 21, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Jeffrey W. Honeycutt, Fernando Gonzalez, Fawad Ahmed
  • Patent number: 5907503
    Abstract: An SRAM memory cell is provided in which a pair of cross-coupled n-type MOS pull-down transistors are coupled to respective parasitically formed bipolar pull-up transistors. The memory cell is formed within a semiconductor layer which extends over a buried layer. The bipolar transistors are formed parasitically from the buried layer and the semiconductor layer used to form the pull-down transistors. The bases of the bipolar transistors may also be dynamically controlled. An SRAM memory array having a plurality of such memory cells and a computer system incorporating the SRAM memory array are also provided.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: May 25, 1999
    Assignee: Micron Technology, Inc.
    Inventors: David A. Kao, Fawad Ahmed