Patents Assigned to FASL, LLC
  • Patent number: 7033957
    Abstract: Process for reducing charge leakage in a SONOS flash memory device, including in one embodiment, forming a bottom oxide layer of an ONO structure on the semiconductor substrate to form an oxide/silicon interface having a first oxygen content adjacent the oxide/silicon interface; treating the bottom oxide layer to increase the first oxygen content to a second oxygen content adjacent the oxide/silicon interface; and depositing a nitride charge-storage layer on the bottom oxide layer. In another embodiment, process for reducing charge leakage in a SONOS flash memory device, including forming a bottom oxide layer of an ONO structure on a surface of the semiconductor substrate having an oxide/silicon interface with a super-stoichiometric oxygen content adjacent the oxide/silicon interface; and depositing a nitride charge-storage layer on the bottom oxide layer.
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: April 25, 2006
    Assignee: FASL, LLC
    Inventors: Hidehiko Shiraiwa, Tazrien Kamal, Mark Ramsbey, Inkuk Kang, Jaeyong Park, Rinji Sugino, Jean Y. Yang, Fred T K Cheung, Arvind Halliyal, Amir H. Jafarpour
  • Patent number: 6977195
    Abstract: For characterizing bulk leakage current of a junction, a center junction surrounded by an isolation structure is formed with a first depth. In addition, at least one periphery junction having a second depth greater than the first depth is formed in a portion of the center junction adjacent the isolation structure. A junction silicide is formed with the center and periphery junctions. The magnitude of a reverse-bias voltage across the junction silicide and the P-well is incremented for determining a critical magnitude of the reverse-bias when current through the junction silicide and the P-well reaches a threshold current density.
    Type: Grant
    Filed: August 16, 2004
    Date of Patent: December 20, 2005
    Assignee: FASL, LLC
    Inventors: John J. Bush, Wen-Jie Qi, Robert Dawson
  • Patent number: 6969886
    Abstract: A SONOS flash memory device, including a semiconductor substrate; an ONO structure formed on the semiconductor substrate, the ONO structure including a bottom oxide layer, a dielectric charge storage layer and a top oxide layer, the bottom oxide layer having a super-stoichiometric oxygen content and an oxygen vacancy content of about 1010/cm2 or less, wherein the bottom oxide layer exhibits a reduced charge leakage relative to a bottom oxide layer having a stoichiometric or sub-stoichiometric oxygen content and a greater number of oxygen vacancies. In one embodiment, the bottom oxide layer has an oxygen vacancy content of substantially zero.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: November 29, 2005
    Assignee: FASL, LLC
    Inventors: Jaeyong Park, Hidehiko Shiraiwa, Arvind Halliyal, Jean Y. Yang, Inkuk Kang, Tazrien Kamal, Amir H. Jafarpour
  • Patent number: 6958511
    Abstract: Process of fabricating multi-bit charge trapping dielectric flash memory device, including forming on a semiconductor substrate a bottom oxide layer to define a substrate/oxide interface, in which the bottom oxide layer includes a first oxygen concentration and a first nitrogen concentration; and adding a quantity of nitrogen to the bottom oxide layer, whereby the bottom oxide layer includes a first region adjacent the charge storage layer and a second region adjacent the substrate/oxide interface, the second region having a second oxygen concentration and a second nitrogen concentration, in which the second nitrogen concentration exceeds the first nitrogen concentration, provided that the second nitrogen concentration does not exceed the second oxygen concentration. In one embodiment, the first nitrogen concentration is substantially zero.
    Type: Grant
    Filed: October 6, 2003
    Date of Patent: October 25, 2005
    Assignee: FASL, LLC
    Inventors: Arvind Halliyal, Amir H. Jafarpour, Hidehiko Shiraiwa, Tazrien Kamal, Mark Ramsbey, Jaeyong Park
  • Patent number: 6955965
    Abstract: Process for fabricating a charge trapping dielectric flash memory device including steps of providing a semiconductor substrate; forming on the semiconductor substrate a bottom oxide layer; depositing on the bottom oxide layer a nitride layer, the deposited nitride layer having a first hydrogen content; and applying a treatment to reduce the first hydrogen content to a second hydrogen content.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: October 18, 2005
    Assignee: FASL, LLC
    Inventors: Arvind Halliyal, Tazrien Kamal, Hidehiko Shiraiwa, Jean Y. Yang
  • Patent number: 6949481
    Abstract: Process for fabricating a semiconductor device including steps of providing a semiconductor substrate having formed thereon a semiconductor device; depositing over the semiconductor device a spacer layer, the spacer layer having a first hydrogen content; and applying a treatment to reduce the first hydrogen content to a second hydrogen content. The invention is particularly useful when applied to flash memory devices such as a charge trapping dielectric flash memory device.
    Type: Grant
    Filed: December 9, 2003
    Date of Patent: September 27, 2005
    Assignee: FASL, LLC
    Inventors: Arvind Halliyal, Fred T K Cheung, Rinji Sugino, Hidehiko Shiraiwa, Tazrien Kamal, Jean Y. Yang
  • Patent number: 6912163
    Abstract: A charge trapping dielectric memory device. The memory device includes a gate electrode disposed over a dielectric stack that includes a dielectric charge trapping layer. The gate electrode has a work function of about 4.6 eV to about 5.2 eV.
    Type: Grant
    Filed: September 9, 2003
    Date of Patent: June 28, 2005
    Assignee: FASL, LLC
    Inventors: Wei Zheng, Yun Wu, Hidehiko Shiraiwa, Mark T. Ramsbey, Tazrien Kamal
  • Patent number: 6859393
    Abstract: A ground structure for page read and page write for flash memory. An array structure of flash memory cells comprises a plurality of sectors. Each sector comprises I/O blocks plus reference arrays and an array of redundant cells. Each I/O block comprises sub I/O blocks. Each sub I/O block within an I/O block, as well as other structures including reference cells, redundant cells and edge structures is coupled to a unique ground reference signal. These unique ground reference signals may be selectively coupled to a system ground or a biased ground reference. This novel ground arrangement enables a page read operation in which one bit from each sub I/O block can be read simultaneously. In addition, one bit from each I/O block may be programmed simultaneously. Further, the ground reference voltage for cells of the array may be selectively adjusted to optimize operation.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: February 22, 2005
    Assignee: FASL, LLC
    Inventors: Tien-Chun Yang, Shigekazu Yamada, Ming-Huei Shieh, Pau-Ling Chen
  • Patent number: 6809033
    Abstract: One aspect of the invention relates to a method of removing a hard mask from a surface, especially a silicon surface. The hard mask is removed by first applying a sacrificial coating and then plasma etching. The sacrificial material fills pattern gaps formed using the hard mask and protects insulators, such as oxides, within those pattern gaps. The sacrificial material is removed together with the hard mask by the plasma etching. The invention provides a process for removing hard masks from silicon layers without significantly damaging either the silicon layer or any exposed oxides and can be applied in a variety of integrated circuit device manufacturing processes, such as patterning the floating gate layer of a flash memory device.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: October 26, 2004
    Assignee: FASL, LLC
    Inventors: Angela Hui, Jusuke Ogura
  • Patent number: 6803275
    Abstract: Process for fabricating a SONOS flash memory device, including in one embodiment, forming a bottom oxide layer of an ONO structure on a semiconductor substrate, wherein the bottom oxide layer has a first oxygen vacancy content; treating the bottom oxide layer to decrease the first oxygen vacancy content to a second oxygen vacancy content; and depositing a dielectric charge-storage layer on the bottom oxide layer. In another embodiment, a process for fabricating a SONOS flash memory device includes forming a bottom oxide layer of an ONO structure on the semiconductor substrate under strongly oxidizing conditions, wherein the bottom oxide layer has a super-stoichiometric oxygen content and an oxygen vacancy content reduced relative to a bottom oxide layer formed by a conventional process; and depositing a dielectric charge-storage layer on the bottom oxide layer.
    Type: Grant
    Filed: December 3, 2002
    Date of Patent: October 12, 2004
    Assignee: FASL, LLC
    Inventors: Jaeyong Park, Hidehiko Shiraiwa, Arvind Halliyal, Jean Y. Yang, Inkuk Kang, Tazrien Kamal, Amir H. Jafarpour
  • Patent number: 6791880
    Abstract: A non-volatile memory read circuit having adjustable current sources to provide end of life simulation. A flash memory device comprising a reference current source used to provide a reference current for comparison to the current of a memory cell being read, includes an adjustable current source in parallel with the memory cell being read, and an adjustable current source in parallel with the reference current source. The current from the memory cell, reference current source, and their parallel adjustable current sources are input to cascode circuits for conversion to voltages that are compared by a sense amplifier. The behavior of the cascode circuits and sense amplifier in response to changes in the memory cell and reference current source may be evaluated by adjusting the adjustable current sources so that the combined current at each input to the sense amplifier simulates the current of the circuit after aging or cycling.
    Type: Grant
    Filed: May 6, 2003
    Date of Patent: September 14, 2004
    Assignee: FASL, LLC
    Inventors: Kazuhiro Kurihara, Binh Quang Le, Pau-Ling Chen, Darlene Hamilton, Edward Hsia
  • Patent number: 6730564
    Abstract: The present invention provides a process for saliciding word lines in a virtual ground array flash memory device without causing shorting between bit lines. According to one aspect of the invention, saliciding takes place prior to patterning one or more layers of a memory cell stack. The unpatterned layers protect the substrate between word lines from becoming salicided. The invention provides virtual ground array flash memory devices with doped and salicided word lines, but no shorting between bit lines, even in virtual ground arrays where there are no oxide island isolation regions between word lines. Potential advantages of such structures include reduced size, reduced number of processing steps, and reduced exposure to high temperature cycling.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: May 4, 2004
    Assignee: FASL, LLC
    Inventors: Mark T. Ramsbey, Yu Sun, Chi Chang, Hidehiko Shiraiwa
  • Patent number: 6707078
    Abstract: One aspect of the present invention relates to a SONOS type non-volatile semiconductor memory device having improved erase speed, the device containing bitlines extending in a first direction; wordlines extending in a second direction, the wordlines comprising functioning wordlines and at least one dummy wordline, wherein the dummy wordline is positioned near at least one of a bitline contact and an edge of the core region, and the dummy wordline is treated so as not to cycle between on and off states.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: March 16, 2004
    Assignee: Fasl, LLC
    Inventors: Hidehiko Shiraiwa, Yider Wu, Jean Yee-Mei Yang, Mark T. Ramsbey, Darlene G. Hamilton