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: 20080191636
    Abstract: An electroluminescence (EL) device and a method are provided for fabricating said device with a nanotip electrode. The method comprises: forming a bottom electrode with nanotips; forming a Si phosphor layer adjacent the nanotips; and, forming a transparent top electrode. The Si phosphor layer is interposed between the bottom and top electrodes. The nanotips may have a tip base size of about 50 nanometers, or less, a tip height in the range of 5 to 50 nm, and a nanotip density of greater than 100 nanotips per square micrometer. Typically, the nanotips are formed from iridium oxide (IrOx) nanotips. A MOCVD process forms the Ir bottom electrode. The IrOx nanotips are grown from the Ir. In one aspect, the Si phosphor layer is a SRSO layer. In response to an SRSO annealing step, nanocrystalline SRSO is formed with nanocrystals having a size in the range of 1 to 10 nm.
    Type: Application
    Filed: March 5, 2008
    Publication date: August 14, 2008
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Gregory M. Stecker, Robert A. Barrowcliff
  • Patent number: 7402456
    Abstract: A method is provided for forming a Pr0.3Ca0.7MnO3 (PCMO) thin film with crystalline structure-related memory resistance properties. The method comprises: forming a PCMO thin film with a first crystalline structure; and, changing the resistance state of the PCMO film using pulse polarities responsive to the first crystalline structure. In one aspect the first crystalline structure is either amorphous or a weak-crystalline. Then, the resistance state of the PCMO film is changed in response to unipolar pulses. In another aspect, the PCMO thin film has either a polycrystalline structure. Then, the resistance state of the PCMO film changes in response to bipolar pulses.
    Type: Grant
    Filed: April 23, 2004
    Date of Patent: July 22, 2008
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Wei-Wei Zhuang, Tingkai Li, Sheng Teng Hsu, Fengyan Zhang
  • Publication number: 20080157354
    Abstract: A method of fabricating a stacked nanostructure array includes preparing a substrate; forming a bottom electrode directly on the substrate; growing a first nanostructure array directly on the bottom electrode; forming an insulating layer on the first nanostructure array; exposing the upper surface of the first nanostructure array; depositing a second, and subsequent, nanostructure array on a nanostructure array immediately below the second and subsequent nanostructure array; repeating said forming, said exposing and said depositing a subsequent steps to form a stacked nanostructure array; removing an uppermost insulating layer; and forming a top electrode on an uppermost nanostructure array. A sensor incorporating the nanostructure array includes top and bottom electrodes with plural layers of nanostructure array therebetween.
    Type: Application
    Filed: January 3, 2007
    Publication date: July 3, 2008
    Inventors: Fengyan Zhang, Sheng Teng Hsu
  • Patent number: 7379320
    Abstract: An MFIS memory array having a plurality of MFIS memory transistors with a word line connecting a plurality of MFIS memory transistor gates, wherein all MFIS memory transistors connected to a common word line have a common source, each transistor drain serves as a bit output, and all MFIS channels along a word line are separated by a P+ region and are further joined to a P+ substrate region on an SOI substrate by a P+ region is provided. Also provided are methods of making an MFIS memory array on an SOI substrate; methods of performing a block erase of one or more word lines, and methods of selectively programming a bit.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: May 27, 2008
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Patent number: 7364924
    Abstract: An electroluminescence (EL) device and a method are provided for fabricating said device with a nanotip electrode. The method comprises: forming a bottom electrode with nanotips; forming a Si phosphor layer adjacent the nanotips; and, forming a transparent top electrode. The Si phosphor layer is interposed between the bottom and top electrodes. The nanotips may have a tip base size of about 50 nanometers, or less, a tip height in the range of 5 to 50 nm, and a nanotip density of greater than 100 nanotips per square micrometer. Typically, the nanotips are formed from iridium oxide (IrOx) nanotips. A MOCVD process forms the Ir bottom electrode. The IrOx nanotips are grown from the Ir. In one aspect, the Si phosphor layer is a SRSO layer. In response to an SRSO annealing step, nanocrystalline SRSO is formed with nanocrystals having a size in the range of 1 to 10 nm.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: April 29, 2008
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Gregory M. Stecker, Robert A. Barrowcliff
  • Publication number: 20080092955
    Abstract: A method of fabricating a photovoltaic cell for use in a solar cell structure includes preparing a first substrate; preparing a TiO2 precursor; preparing a cold wall CVD chamber; placing the first substrate in the cold wall CVD chamber; forming a transparent conducting electrode on the first substrate; depositing a porous column TiO2 film on the transparent conducting electrode; depositing a photosensitive material in and on the porous column TiO2 film; forming a top electrode on the photovoltaic cell; and incorporating the photovoltaic cell into a solar cell structure. The method of the invention is suitable for forming photovoltaic cells which may be of the dye-sensitized solar cell (DSSC) type, having a liquid or solid-state electrolyte therein, or an ordered organic-inorganic heterojunction photovoltaic cell.
    Type: Application
    Filed: October 16, 2006
    Publication date: April 24, 2008
    Inventors: Fengyan Zhang, Robert A. Barrowcliff, Gregory M. Stecker, Sheng Teng Hsu
  • Publication number: 20080096345
    Abstract: A method is provided for forming a NanoElectroChemical (NEC) cell. The method provides a bottom electrode with a top surface. Nanowire shells are formed. Each nanowire shell has a nanowire and a sleeve, with the nanowire connected to the bottom electrode top surface. A top electrode is formed overlying the nanowire shells. A main cavity is formed between the top electrode and bottom electrodes, partially displaced by a first plurality of nanowire shells. Electrolyte cavities are formed between the sleeves and nanowires by etching the first sacrificial layer. In one aspect, electrolyte cavities are formed between the bottom electrode top surface and a shell coating layer joining the sleeve bottom openings. Then, the main and electrolyte cavities are filled with either a liquid or gas phase electrolyte. In a different aspect, the first sacrificial layer is a solid phase electrolyte that is not etched away.
    Type: Application
    Filed: October 12, 2006
    Publication date: April 24, 2008
    Inventors: Fengyan Zhang, David R. Evans, Sheng Teng Hsu
  • Publication number: 20080010707
    Abstract: An ambient environment nanowire sensor and corresponding fabrication method have been provided. The method includes: forming a substrate such as Silicon (Si) or glass; growing nanowires; depositing an insulator layer overlying the nanowires; etching to expose tips of the nanowires; forming a patterned metal electrode, with edges, overlying the tips of the nanowires; and, etching to expose the nanowires underlying the electrode edges. The nanowires can be a material such as IrO2, TiO2, InO, ZnO, SnO2, Sb2O3, or In2O3, to mane just a few examples. The insulator layer can be a spin-on glass (SOG) or low-k dielectric. In one aspect, the resultant structure includes exposed nanowires grown from the doped substrate regions and an insulator core with embedded nanowires. In a different aspect, the method forms a growth promotion layer overlying the substrate. The resultant structure includes exposed nanowires grown from the selectively formed growth promotion layer.
    Type: Application
    Filed: November 1, 2005
    Publication date: January 10, 2008
    Inventors: Fengyan Zhang, Robert Barrowcliff, Jong-Jan Lee, Sheng Hsu
  • Patent number: 7267996
    Abstract: A method of etching an iridium layer for use in a ferroelectric device includes preparing a substrate; depositing a barrier layer on the substrate; depositing an iridium layer on the barrier layer; depositing a hard mask layer on the iridium layer; depositing, patterning and developing a photoresist layer on the hard mask; etching the hard mask layer; etching the iridium layer using argon, oxygen and chlorine chemistry in a high-density plasma reactor; and completing the ferroelectric device.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: September 11, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, David R. Evans, Wei Pan, Lisa H. Stecker, Jer-Shen Maa
  • Patent number: 7255745
    Abstract: Iridium oxide (IrOx) nanowires and a method forming the nanowires are provided. The method comprises: providing a growth promotion film with non-continuous surfaces, having a thickness in the range of 0.5 to 5 nanometers (nm), and made from a material such as Ti, Co, Ni, Au, Ta, polycrystalline silicon (poly-Si), SiGe, Pt, Ir, TiN, or TaN; establishing a substrate temperature in the range of 200 to 600 degrees C.; introducing oxygen as a precursor reaction gas; introducing a (methylcyclopentadienyl)(1,5-cyclooctadiene)iridium(I) precursor; using a metalorganic chemical vapor deposition (MOCVD) process, growing IrOx nanowires from the growth promotion film surfaces. The IrOx nanowires have a diameter in the range of 100 to 1000 ?, a length in the range of 1000 ? to 2 microns, an aspect ratio (length to width) of greater than 50:1. Further, the nanowires include single-crystal nanowire cores covered with an amorphous layer having a thickness of less than 10 ?.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: August 14, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Robert A. Barrowcliff, Sheng Teng Hsu
  • Patent number: 7256429
    Abstract: A method is provided for forming a buffered-layer memory cell. The method comprises: forming a bottom electrode; forming a colossal magnetoresistance (CMR) memory film overlying the bottom electrode; forming a memory-stable semiconductor buffer layer, typically a metal oxide, overlying the memory film; and, forming a top electrode overlying the semiconductor buffer layer. In some aspects of the method the semiconductor buffer layer is formed from YBa2Cu3O7?X (YBCO), indium oxide (In2O3), or ruthenium oxide (RuO2), having a thickness in the range of 10 to 200 nanometers (nm). The top and bottom electrodes may be TiN/Ti, Pt/TiN/Ti, In/TiN/Ti, PtRhOx compounds, or PtIrOx compounds. The CMR memory film may be a Pr1?XCaXMnO3 (PCMO) memory film, where x is in the region between 0.1 and 0.6, with a thickness in the range of 10 to 200 nm.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: August 14, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang, Wei Pan, Wei-Wei Zhuang, David R. Evans, Masayuki Tajiri
  • Publication number: 20070167008
    Abstract: A non-volatile memory resistor cell with a nanotip electrode, and corresponding fabrication method are provided. The method comprises: forming a first electrode with nanotips; forming a memory resistor material adjacent the nanotips; and, forming a second electrode adjacent the memory resistor material, where the memory resistor material is interposed between the first and second electrodes. Typically, the nanotips are iridium oxide (IrOx) and have a tip base size of about 50 nanometers, or less, a tip height in the range of 5 to 50 nm, and a nanotip density of greater than 100 nanotips per square micrometer. In one aspect, the substrate material can be silicon, silicon oxide, silicon nitride, or a noble metal. A metalorganic chemical vapor deposition (MOCVD) process is used to deposit Ir. The IrOx nanotips are grown from the deposited Ir.
    Type: Application
    Filed: March 14, 2007
    Publication date: July 19, 2007
    Inventors: Sheng Hsu, Fengyan Zhang, Gregory Stecker, Robert Barrowcliff
  • Publication number: 20070111368
    Abstract: A photovoltaic (PV) structure is provided, along with a method for forming a PV structure with a conductive nanowire array electrode. The method comprises: forming a bottom electrode with conductive nanowires; forming a first semiconductor layer of a first dopant type (i.e., n-type) overlying the nanowires; forming a second semiconductor layer of a second dopant type, opposite of the first dopant type (i.e., p-type), overlying the first semiconductor layer; and, forming a top electrode overlying the second semiconductor layer. The first and second semiconductor layers can be a material such as a conductive polymer, a conjugated polymer with a fullerene derivative, and inorganic materials such as CdSe, CdS, Titania, or ZnO. The conductive nanowires can be a material such as IrO2, In2O3, SnO2, or indium tin oxide (ITO).
    Type: Application
    Filed: November 16, 2005
    Publication date: May 17, 2007
    Inventors: Fengyan Zhang, Robert Barrowcliff, Sheng Hsu
  • Patent number: 7208372
    Abstract: A non-volatile memory resistor cell with a nanotip electrode, and corresponding fabrication method are provided. The method comprises: forming a first electrode with nanotips; forming a memory resistor material adjacent the nanotips; and, forming a second electrode adjacent the memory resistor material, where the memory resistor material is interposed between the first and second electrodes. Typically, the nanotips are iridium oxide (IrOx) and have a tip base size of about 50 nanometers, or less, a tip height in the range of 5 to 50 nm, and a nanotip density of greater than 100 nanotips per square micrometer. In one aspect, the substrate material can be silicon, silicon oxide, silicon nitride, or a noble metal. A metalorganic chemical vapor deposition (MOCVD) process is used to deposit Ir. The IrOx nanotips are grown from the deposited Ir.
    Type: Grant
    Filed: January 19, 2005
    Date of Patent: April 24, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Gregory M. Stecker, Robert A. Barrowcliff
  • Patent number: 7196387
    Abstract: An asymmetric-area memory cell, and a fabrication method for forming an asymmetric-area memory cell, are provided. The method comprises: forming a bottom electrode having an area; forming a CMR memory film overlying the bottom electrode, having an asymmetric area; and, forming a top electrode having an area, less than the bottom electrode area, overlying the CMR film. In one aspect, the CMR film has a first area adjacent the top electrode and a second area, greater than the first area, adjacent the bottom electrode. Typically, the CMR film first area is approximately equal to the top electrode area, although the CMR film second area may be less than the bottom electrode area.
    Type: Grant
    Filed: July 1, 2005
    Date of Patent: March 27, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang
  • Publication number: 20070049029
    Abstract: A method of etching a top electrode/ferroelectric stack using an etch stop layer includes forming a first layer of a first dielectric material on a substrate; forming a bottom electrode in the first layer of a first dielectric material; depositing an etch stop layer on the first layer of the first dielectric material and the bottom electrode, including forming a hole therein; depositing a layer of ferroelectric material and depositing top electrode material on the ferroelectric material to form a top electrode/ferroelectric stack; stack etching the top electrode and ferroelectric material; depositing a layer of a second dielectric material encapsulating the top electrode and ferroelectric material; etching the layer of the second dielectric material to form a sidewall about the top electrode and ferroelectric material; and depositing a second and third layers of the first dielectric material.
    Type: Application
    Filed: August 30, 2005
    Publication date: March 1, 2007
    Inventors: Bruce Ulrich, Lisa Stecker, Fengyan Zhang, Sheng Hsu
  • Patent number: 7169637
    Abstract: A one-mask etching method for use with a PCMO-containing RRAM to reduce stack side-wall residuals, includes preparing a substrate, taken from the group of substrates consisting of silicon, silicon dioxide and polysilicon; depositing a bottom electrode on the substrate; depositing a PCMO layer on the bottom electrode; depositing a top electrode on the PCMO layer; depositing a hard mask on the top electrode; depositing and patterning a photoresist layer on the hard mask; etching the hard mask; etching the top electrode using a first etching process having an etching atmosphere consisting of Ar, O2, and Cl2; etching the PCMO layer using an etching process taken from the group of etching processes consisting of the first etching process and a second etching process having an etching atmosphere consisting of Ar and O2. etching the bottom electrode using the first etching process; and completing the RRAM device.
    Type: Grant
    Filed: July 1, 2004
    Date of Patent: January 30, 2007
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Lisa H. Stecker, Bruce D. Ulrich, Sheng Teng Hsu
  • Patent number: 7148533
    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: Grant
    Filed: September 14, 2005
    Date of Patent: December 12, 2006
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang
  • Patent number: 7141481
    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: July 29, 2004
    Date of Patent: November 28, 2006
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Wei-Wei Zhuang, Wei Pan, Fengyan Zhang
  • Patent number: 7112837
    Abstract: An MFIS memory array having a plurality of MFIS memory transistors with a word line connecting a plurality of MFIS memory transistor gates, wherein all MFIS memory transistors connected to a common word line have a common source, each transistor drain serves as a bit output, and all MFIS channels along a word line are separated by a P+ region and are further joined to a P+ substrate region on an SOI substrate by a P+ region is provided. Also provided are methods of making an MFIS memory array on an SOI substrate; methods of performing a block erase of one or more word lines, and methods of selectively programming a bit.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: September 26, 2006
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li