Patents by Inventor Fengyan Zhang

Fengyan Zhang 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).

  • Publication number: 20050009286
    Abstract: A method of fabricating a nano-scale resistance cross-point memory array includes preparing a silicon substrate; depositing silicon oxide on the substrate to a predetermined thickness; forming a nano-scale trench in the silicon oxide; depositing a first connection line in the trench; depositing a memory resistor layer in the trench on the first connection line; depositing a second connection line in the trench on the memory resistor layer; and completing the memory array. A cross-point memory array includes a silicon substrate; a first connection line formed on the substrate; a colossal magnetoresistive layer formed on the first connection line; a silicon nitride layer formed on a portion of the colossal magnetoresistive layer; and a second connection line formed adjacent the silicon nitride layer and on the colossal magnetoresistive layer.
    Type: Application
    Filed: July 29, 2004
    Publication date: January 13, 2005
    Inventors: Sheng Hsu, Wei-Wei Zhuang, Wei Pan, Fengyan Zhang
  • Patent number: 6833572
    Abstract: An electrode for use in a ferroelectric device includes a bottom electrode; a ferroelectric layer; and a top electrode formed on the ferroelectric layer and formed of a combination of metals, including a first metal take from the group of metals consisting of platinum and iridium, and a second metal taken from the group of metals consisting of aluminum and titanium; wherein the top electrode acts as a passivation layer and wherein the top electrode remains conductive following high temperature annealing in a hydrogen atmosphere.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: December 21, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Tingkai Li, Hong Ying, Yoshi Ono, Sheng Teng Hsu
  • Publication number: 20040235200
    Abstract: A memory cell and method for controlling the resistance properties in a memory material are provided. The method comprises: forming manganite; annealing the manganite in an oxygen atmosphere; controlling the oxygen content in the manganite in response to the annealing; and, controlling resistance through the manganite in response to the oxygen content. The manganite is perovskite-type manganese oxides with the general formula RE1-xAExMnOy, where RE is a rare earth ion and AE is an alkaline-earth ion, with x in the range between 0.1 and 0.5. Controlling the oxygen content in the manganite includes forming an oxygen-rich RE1-xAExMnOy region where y is greater than 3. A low resistance results in the oxygen-rich manganite region. When y is less than 3, a high resistance is formed. More specifically, the process forms a low resistance oxygen-rich manganite region adjacent an oxygen-deficient high resistance manganite region.
    Type: Application
    Filed: May 21, 2003
    Publication date: November 25, 2004
    Applicant: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang
  • Patent number: 6819583
    Abstract: A ferroelectric thin film resistor memory array is formed on a substrate and includes plural memory cells arranged in an array of rows and columns; wherein each memory cell includes: a FE resistor having a pair of terminals, and a transistor associated with each resistor, wherein each transistor has a gate, a drain and a source, and wherein the drain of each transistor is electrically connected to one terminal of its associated resistor; a word line connected to the gate of each transistor in a row; a programming line connected to each memory cell in a column; and a bit line connected to each memory cell in a column.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: November 16, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang
  • Publication number: 20040180507
    Abstract: A method of applying a PCMO thin film on an iridium substrate for use in a RRAM device, includes preparing a substrate; depositing a barrier layer on the substrate; depositing a layer of iridium on the barrier layer; spin coating a layer of PCMO on the iridium; baking the PCMO and substrate in a three-step baking process; post-bake annealing the substrate and the PCMO in a RTP chamber; repeating said spin coating, baking and annealing steps until the PCMO has a desired thickness; annealing the substrate and PCMO; depositing a top electrode; and completing the RRAM device.
    Type: Application
    Filed: March 10, 2003
    Publication date: September 16, 2004
    Applicant: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Wei-Wei Zhuang, Wei Pan, Sheng Teng Hsu
  • Publication number: 20040171215
    Abstract: A low-capacitance one-resistor/one-diode (1R1D) R-RAM array with a floating p-well is provided. The fabrication method comprises: forming an integrated circuit (IC) substrate; forming an n-doped buried layer (buried n layer) of silicon overlying the substrate; forming n-doped silicon sidewalls overlying the buried n layer; forming a p-doped well of silicon (p-well) overlying the buried n layer; and, forming a 1R1D R-RAM array overlying the p-well. Typically, the combination of the buried n layer and the n-doped sidewalls form an n-doped well (n-well) of silicon. Then, the p-well is formed inside the n-well. In other aspects, the p-well has sidewalls, and the method further comprises: forming an oxide insulator overlying the p-well sidewalls, between the n-well and the R-RAM array.
    Type: Application
    Filed: February 27, 2003
    Publication date: September 2, 2004
    Inventors: Sheng Teng Hsu, Wei Pan, Wei-Wei Zhuang, Fengyan Zhang
  • Patent number: 6774004
    Abstract: A method of fabricating a nano-scale resistance cross-point memory array includes preparing a silicon substrate; depositing silicon oxide on the substrate to a predetermined thickness; forming a nano-scale trench in the silicon oxide; depositing a first connection line in the trench; depositing a memory resistor layer in the trench on the first connection line; depositing a second connection line in the trench on the memory resistor layer; and completing the memory array. A cross-point memory array includes a silicon substrate; a first connection line formed on the substrate; a colossal magnetoresistive layer formed on the first connection line; a silicon nitride layer formed on a portion of the colossal magnetoresistive layer; and a second connection line formed adjacent the silicon nitride layer and on the colossal magnetoresistive layer.
    Type: Grant
    Filed: March 17, 2003
    Date of Patent: August 10, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Wei-Wei Zhuang, Wei Pan, Fengyan Zhang
  • Patent number: 6774054
    Abstract: A method of forming a PCMO thin film in a RRAM device includes preparing a substrate; depositing a metal barrier layer on the substrate; forming a bottom electrode on the barrier layer; spin-coating a layer of Pr1−xCaxMnO3 (PCMO) on the bottom electrode using a PCMO precursor; baking the PCMO thin film in one or more baking steps; annealing the PCMO thin film in a first annealing step after each spin-coating step; repeating the spin-coating step, the baking step and the first annealing step until the PCMO thin film has a desired thickness; annealing the PCMO thin film in a second annealing step, thereby producing a PCMO thin film having a crystalline structure of Pr1−xCaxMnO3, where 0.2<=X<=0.5; depositing a top electrode; patterning the top electrode; and completing the RRAM device.
    Type: Grant
    Filed: August 13, 2003
    Date of Patent: August 10, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Wei-Wei Zhuang, David R. Evans, Sheng Teng Hsu
  • Publication number: 20040136223
    Abstract: A ferroelectric thin film resistor memory array is formed on a substrate and includes plural memory cells arranged in an array of rows and columns; wherein each memory cell includes: a FE resistor having a pair of terminals, and a transistor associated with each resistor, wherein each transistor has a gate, a drain and a source, and wherein the drain of each transistor is electrically connected to one terminal of its associated resistor; a word line connected to the gate of each transistor in a row; a programming line connected to each memory cell in a column; and a bit line connected to each memory cell in a column.
    Type: Application
    Filed: January 15, 2003
    Publication date: July 15, 2004
    Applicant: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang
  • Patent number: 6762063
    Abstract: A method of fabricating a non-volatile ferroelectric memory transistor includes forming a bottom electrode; depositing a ferroelectric layer over an active region beyond the margins of the bottom electrode; depositing a top electrode on the ferroelectric layer; and metallizing the structure to form a source electrode, a gate electrode and a drain electrode. A non-volatile ferroelectric memory transistor includes a bottom electrode formed above a gate region, wherein the bottom electrode has a predetermined area within a peripheral boundary; a ferroelectric layer extending over and beyond the bottom electrode peripheral boundary; and a top electrode formed on said ferroelectric layer.
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: July 13, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Patent number: 6759250
    Abstract: The ferroelectric structure including a Pt/Ir layered electrode used in conjunction with a lead germanate (Pb5Ge3O11) thin film is provided. The electrode exhibits good adhesion to the substrate, and barrier properties resistant to oxygen and lead. Ferroelectric properties are improved, without detriment to the leakage current, by using a thin IrO2 layer formed in situ, during the MOCVD lead germanate (Pb5Ge3O11) thin film process. By using a Pt/Ir electrode, a relatively low MOCVD processing temperature is required to achieve c-axis oriented lead germanate (Pb5Ge3O11) thin film. The temperature range of MOCVD c-axis oriented lead germanate (Pb5Ge3O11) thin film on top of Pt/Ir is 400-500° C. Further, a relatively large nucleation density is obtained, as compared to using single-layer iridium electrode. Therefore, the lead germanate (Pb5Ge3O11) thin film has a smooth surface, a homogeneous microstructure, and homogeneous ferroelectric properties.
    Type: Grant
    Filed: July 15, 2002
    Date of Patent: July 6, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Tingkai Li, Sheng Teng Hsu
  • Patent number: 6759252
    Abstract: A passivation layer comprises a titanium-doped aluminum oxide layer for passivation of ferroelectric materials such as Pt/SBt/Ir—Ta—O devices. The titanium-doped aluminum oxide layer for passivation of ferroelectric materials has reduced stress and improved passivation properties, and is easy to deposit and be oxidized. The passivation layer in the MFM Structure resists breakdown and peeling during annealing of the device in a forming gas ambient.
    Type: Grant
    Filed: July 16, 2003
    Date of Patent: July 6, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Sheng Teng Hsu, Hong Ying
  • Patent number: 6737693
    Abstract: A Pb3GeO5 phase PGO thin film is provided. This film has ferroelastic properties that make it ideal for many microelectromechanical applications or as decoupling capacitors in high speed multichip modules. This PGO film is uniquely formed in a MOCVD process that permits a thin film, less than 1 mm, of material to be deposited. The process mixes Pd and germanium in a solvent. The solution is heated to form a precursor vapor which is decomposed. The method provides deposition temperatures and pressures. The as-deposited film is also annealed to enhanced the film's ferroelastic characteristics. A ferroelastic capacitor made from the present invention PGO film is also provided.
    Type: Grant
    Filed: April 14, 2003
    Date of Patent: May 18, 2004
    Inventors: Tingkai Li, Fengyan Zhang, Yoshi Ono, Sheng Teng Hsu
  • Patent number: 6720258
    Abstract: An integrated circuit device, and a method of manufacturing the same, comprises an epitaxial nickel silicide on (100) Si, or a stable nickel silicide on amorphous Si, fabricated with a cobalt interlayer. In one embodiment the method comprises depositing a cobalt (Co) interface layer between the Ni and Si layers prior to the silicidation reaction. The cobalt interlayer regulates the flux of the Ni atoms through the cobalt/nickel/silicon alloy layer formed from the reaction of the cobalt interlayer with the nickel and the silicon so that the Ni atoms reach the Si interface at a similar rate, i.e., without any orientation preference, so as to form a uniform layer of nickel silicide. The nickel silicide may be annealed to form a uniform crystalline nickel disilicide. Accordingly, a single crystal nickel silicide on (100) Si or on amorphous Si is achieved wherein the nickel silicide has improved stability and may be utilized in ultra-shallow junction devices.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: April 13, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Jer-shen Maa, Douglas J. Tweet, Yoshi Ono, Fengyan Zhang, Sheng Teng Hsu
  • Publication number: 20040056276
    Abstract: A passivation layer comprises a titanium-doped aluminum oxide layer for passivation of ferroelectric materials such as Pt/SBt/Ir—Ta—O devices. The titanium-doped aluminum oxide layer for passivation of ferroelectric materials has reduced stress and improved passivation properties, and is easy to deposit and be oxidized. The passivation layer in the MFM Structure resists breakdown and peeling during annealing of the device in a forming gas ambient.
    Type: Application
    Filed: July 16, 2003
    Publication date: March 25, 2004
    Inventors: Fengyan Zhang, Sheng Teng Hsu, Hong Ying
  • Patent number: 6711049
    Abstract: A one-transistor FeRAM memory cell array includes an array of ferroelectric transistors arranged in rows and columns, each transistor having a source, a drain, a channel, a gate oxide layer over the channel and a ferroelectric stack formed on the gate oxide layer; word lines connecting the gate ferroelectric stack top electrodes of transistors in a row of the array; a connection to the channel of all transistors in the array formed by a substrate well; a set of first bit lines connecting the sources of all transistors in a column of the array; and a set of second bit lines connecting the drains of all transistors in a column of the array; wherein the ferroelectric stack has opposed edges, which, when projected to a level of the source, drain and channel, are coincident with an abutted edge of the source and the channel and the drain and the channel, respectively.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: March 23, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Jong-Jan Lee, Fengyan Zhang, Nobuyoshi Awaya
  • Patent number: 6703655
    Abstract: A ferroelectric memory transistor includes a substrate having active regions therein; a gate stack, including: a high-k insulator element, including a high-k cup and a high-k cap; a ferroelectric element, wherein said ferroelectric element is encapsulated within said high-k insulator element; and a top electrode located on a top portion of said high-k insulator; a passivation oxide layer located over the substrate and gate stack; and metalizations to form contacts to the active regions and the gate stack.
    Type: Grant
    Filed: March 10, 2003
    Date of Patent: March 9, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Patent number: 6682995
    Abstract: A conductive barrier, useful as a ferroelectric capacitor electrode, having high temperature stability has been provided. This conductive barrier permits the use of iridium (Ir) metal in IC processes involving annealing. Separating silicon substrate from Ir film with an intervening, adjacent, tantalum (Ta) film has been found to very effective in suppressing diffusion between layers. The Ir prevents the interdiffusion of oxygen into the silicon during annealing. A Ta or TaN layer prevents the diffusion of Ir into the silicon. This Ir/TaN structure protects the silicon interface so that adhesion, conductance, hillock, and peeling problems are minimized. The use of Ti overlying the Ir/TaN structure also helps prevent hillock formation during annealing. A method of forming a multilayer Ir conductive structure and Ir ferroelectric electrode are also provided.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: January 27, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Jer-shen Maa, Sheng Teng Hsu
  • Patent number: 6673664
    Abstract: A method of making a self-aligned ferroelectric memory transistor includes preparing a substrate, shallow trench isolation, n the polysilicon; and forming a gate stack, including: depositing a layer of silicon nitride; selectively etching the silicon nitride, the bottom electrode and the polysilicon; selectively etching the polysilicon to the level of the first dielectric layer; and implanting and activating ions to form a source region and a drain region; forming a sidewall barrier layer; depositing a layer of ferroelectric material; forming a top electrode structure on the ferroelectric material; and finishing the structure, including passivation, oxide depositing and metallization.
    Type: Grant
    Filed: October 16, 2001
    Date of Patent: January 6, 2004
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang
  • Publication number: 20030222291
    Abstract: A ferroelectric memory transistor includes a substrate having active regions therein; a gate stack, including: a high-k insulator element, including a high-k cup and a high-k cap; a ferroelectric element, wherein said ferroelectric element is encapsulated within said high-k insulator element; and a top electrode located on a top portion of said high-k insulator; a passivation oxide layer located over the substrate and gate stack; and metalizations to form contacts to the active regions and the gate stack.
    Type: Application
    Filed: March 10, 2003
    Publication date: December 4, 2003
    Applicant: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li