Patents by Inventor Tingkai Li

Tingkai Li 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: 20030082909
    Abstract: A method of fabricating a memory device includes preparing a silicon substrate; depositing a layer of high-k insulator on the substrate; depositing a layer of buffering metal on the high-k layer; depositing a layer of ferroelectric material on the buffering layer by metal organic chemical vapor deposition; forming a top electrode on the ferroelectric material; and completing the device.
    Type: Application
    Filed: October 30, 2001
    Publication date: May 1, 2003
    Inventors: Tingkai Li, Sheng Teng Hsu, Bruce D. Ulrich, Lisa Stecker
  • Publication number: 20030071292
    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: Application
    Filed: October 16, 2001
    Publication date: April 17, 2003
    Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang
  • Publication number: 20030068848
    Abstract: A ferroelectric transistor gate structure with a ferroelectric gate and passivation sidewalls is provided. The passivation sidewalls serve as an insulator to reduce, or eliminate, the diffusion of oxygen or hydrogen into the ferroelectric gate. A method of forming the ferroelectric gate structure is also provided. The method comprises the steps of forming a sacrificial gate structure, removing the sacrificial gate structure, depositing passivation insulator material, etching the passivation insulator material using anisotropic plasma etching to form passivation sidewalls, depositing a ferroelectric material, polishing the ferroelectric material using CMP, and forming a top electrode overlying the ferroelectric material.
    Type: Application
    Filed: October 28, 2002
    Publication date: April 10, 2003
    Applicant: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Patent number: 6534326
    Abstract: A polycrystalline memory structure is described for improving reliability and yield of devices employing polycrystalline memory materials comprising a polycrystalline memory layer, which has crystal grain boundaries forming gaps between adjacent crystallites overlying a substrate. An insulating material is located at least partially within the gaps to at least partially block the entrance to the gaps. A method of forming a polycrystalline memory structure is also described. A layer of material is deposited and annealed to form a polycrystalline memory material having gaps between adjacent crystallites. An insulating material is deposited over the polycrystalline memory material to at least partially fill the gaps, thereby blocking a portion of each gap.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: March 18, 2003
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang, Wei-Wei Zhuang
  • Patent number: 6531325
    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: June 4, 2002
    Date of Patent: March 11, 2003
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Patent number: 6531324
    Abstract: A ferroelectric transistor gate structure with a ferroelectric gate and passivation sidewalls is provided. The passivation sidewalls serve as an insulator to reduce, or eliminate, the diffusion of oxygen or hydrogen into the ferroelectric gate. A method of forming the ferroelectric gate structure is also provided. The method comprises the steps of forming a sacrificial gate structure, removing the sacrificial gate structure, depositing passivation insulator material, etching the passivation insulator material using anisotropic plasma etching to form passivation sidewalls, depositing a ferroelectric material, polishing the ferroelectric material using CMP, and forming a top electrode overlying the ferroelectric material.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: March 11, 2003
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Publication number: 20030032206
    Abstract: A method of making a ferroelectric memory transistor includes preparing a silicon substrate including forming plural active areas thereon; depositing a layer of gate insulator on the substrate, and depositing a layer of polysilicon over the gate insulator layer; forming a source region, a drain region and a gate electrode; depositing a layer of bottom electrode material and finishing the bottom electrode without damaging the underlying gate insulator and silicon substrate; depositing a layer of ferroelectric material on the bottom electrode; depositing a layer of top electrode material on the ferroelectric material; and finishing the transistor, including passivation oxide deposition, contact hole etching and metalization.
    Type: Application
    Filed: August 13, 2001
    Publication date: February 13, 2003
    Inventors: Sheng Teng Hsu, Tingkai Li, Bruce D. Ulrich
  • Publication number: 20030007319
    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: Application
    Filed: August 27, 2002
    Publication date: January 9, 2003
    Inventors: Fengyan Zhang, Tingkai Li, Hong Ying, Yoshi Ono, Sheng Teng Hsu
  • Patent number: 6503314
    Abstract: A ferroelectric and dielectric source solution for use in chemical vapor deposition processes includes a ferroelectric/dielectric chemical vapor deposition precursor; and a solvent for carrying the ferroelectric/dielectric chemical vapor deposition precursor taken from the group of solvents consisting essentially of type A solvents, including tetraglyme, triglyme, triethylenetetramine, N,N,N′,N′-tetramethylethylenediamine; N,N,N′,N′,N″,N″-pentamethyldiethylenetriamine; and 2,2′-bipyridine; type B solvents including tetrahydrofuran, butyl ethyl ether, tert-butyl ethyl ether, butyl ether, and pentyl ether; and type C solvents including iso-propanol, 2-butanol, 2-ethyl-1-hexanol, 2-pentanol, toluene, xylene and butyl acetate; and mixtures of solvent types A, B and C.
    Type: Grant
    Filed: August 28, 2000
    Date of Patent: January 7, 2003
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Tingkai Li, Wei Wei Zhuang, Sheng Teng Hsu
  • Patent number: 6503763
    Abstract: A MFMOS one transistor memory structure for ferroelectric non-volatile memory devices includes a high dielectric constant material such as ZrO2, HfO2, Y2O3, or La2O3, or the like, or mixtures thereof, to reduce the operation voltage and to increase the memory window and reliability of the device.
    Type: Grant
    Filed: March 27, 2001
    Date of Patent: January 7, 2003
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Tingkai Li, Sheng Teng Hsu, Hong Ying, Bruce D. Ulrich, Yanjun Ma
  • Patent number: 6495378
    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: March 21, 2001
    Date of Patent: December 17, 2002
    Assignee: Sharp Laboratories of America, Inc,
    Inventors: Tingkai Li, Fengyan Zhang, Yoshi Ono, Sheng Teng Hsu
  • Publication number: 20020180045
    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: Application
    Filed: July 15, 2002
    Publication date: December 5, 2002
    Inventors: Fengyan Zhang, Tingkai Li, Sheng Teng Hsu
  • Publication number: 20020177244
    Abstract: A ferroelectric transistor gate structure with a ferroelectric gate and passivation sidewalls is provided. The passivation sidewalls serve as an insulator to reduce, or eliminate, the diffusion of oxygen or hydrogen into the ferroelectric gate. A method of forming the ferroelectric gate structure is also provided. The method comprises the steps of forming a sacrificial gate structure, removing the sacrificial gate structure, depositing passivation insulator material, etching the passivation insulator material using anisotropic plasma etching to form passivation sidewalls, depositing a ferroelectric material, polishing the ferroelectric material using CMP, and forming a top electrode overlying the ferroelectric material.
    Type: Application
    Filed: March 28, 2001
    Publication date: November 28, 2002
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li
  • Patent number: 6483137
    Abstract: A ferroelectric Pb5Ge3O11 (PGO) thin film is provided with a metal organic vapor deposition (MOCVD) process and RTP (Rapid Thermal Process) annealing techniques. The PGO film is substantially crystallization with c-axis orientation at temperature between 450 and 650° C. The PGO film has an average grain size of about 0.5 microns, with a deviation in grain size uniformity of less than 10%. Good ferroelectric properties are-obtained for a 150 nm thick film with Ir electrodes. The films also show fatigue-free characteristics: no fatigue was observed up to 1×109 switching cycles. The leakage currents increase with increasing applied voltage, and are about 3.6×10−7 A/cm2 at 100 kV/cm. The dielectric constant shows a behavior similar to most ferroelectric materials, with a maximum dielectric constant of about 45. These high quality MOCVD Pb5Ge3O11 films can be used for high density single transistor ferroelectric memory applications because of the homogeneity of the PGO film grain size.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: November 19, 2002
    Inventors: Tingkai Li, Fengyan Zhang, Yoshi Ono, Sheng Tang Hsu
  • Patent number: 6475813
    Abstract: A method of fabricating a c-axis ferroelectric thin film includes preparing a substrate; depositing a layer of ferroelectric material by metal organic chemical vapor deposition, including using a precursor solution having a ferroelectric material concentration of about 0.1 M/L at a vaporizer temperature of between about 140° C. to 200° C.; and annealing the substrate and the ferroelectric material at a temperature between about 500° C. to 560° C. for between about 30 minutes to 120 minutes.
    Type: Grant
    Filed: August 13, 2001
    Date of Patent: November 5, 2002
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Tingkai Li, Wei Pan, Sheng Teng Hsu
  • Patent number: 6462366
    Abstract: A method of fabricating a ferroelectric memory transistor using a lithographic process having an alignment tolerance of &dgr;, includes preparing a silicon substrate for construction of a ferroelectric gate unit; implanting boron ions to form a p-well in the substrate; isolating plural device areas on the substrate; forming a FE gate stack surround structure; etching the FE gate stack surround structure to form an opening having a width of L1 to expose the substrate in a gate region; depositing oxide to a thickness of between about 10 nm to 40 nm over the exposed substrate; forming a FE gate stack over the gate region, wherein the FE gate stack has a width of L2, wherein L2≧L1+2&dgr;; depositing a first insulating layer over the structure; implanting arsenic or phosphorous ions to form a source region and a drain region; annealing the structure; depositing a second insulating layer; and metallizing the structure.
    Type: Grant
    Filed: January 12, 2000
    Date of Patent: October 8, 2002
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Sheng Teng Hsu, Jer-shen Maa, Fengyan Zhang, Tingkai Li
  • Publication number: 20020142487
    Abstract: A MFMOS one transistor memory structure for ferroelectric non-volatile memory devices includes a high dielectric constant material such as ZrO2, HfO2, Y2O3, or La2O3, or the like, or mixtures thereof, to reduce the operation voltage and to increase the memory window and reliability of the device.
    Type: Application
    Filed: March 27, 2001
    Publication date: October 3, 2002
    Inventors: Tingkai Li, Sheng Teng Hsu, Hong Ying, Bruce D. Ulrich, Yanjun Ma
  • Patent number: 6457479
    Abstract: A method of cleaning a metal oxide thin film on a silicon wafer, includes dipping the wafer in an organic solvent; drying the wafer in a nitrogen atmosphere; and stripping any photoresist from the wafer in an oxygen atmosphere under partial vacuum at a temperature of about 200° C. The wafer may also be cleaned by dipping in a polar organic solvent and subjecting the wafer to ultrasound while immersed in the solvent.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: October 1, 2002
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Wei-Wei Zhuang, Fengyan Zhang, Sheng Teng Hsu, Tingkai Li
  • Patent number: 6440752
    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: March 26, 2001
    Date of Patent: August 27, 2002
    Assignee: Sharp Laboratories of America, Inc.
    Inventors: Fengyan Zhang, Tingkai Li, Hong Ying, Yoshi Ono, Sheng Teng Hsu
  • Publication number: 20020109166
    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: Application
    Filed: February 13, 2001
    Publication date: August 15, 2002
    Inventors: Sheng Teng Hsu, Fengyan Zhang, Tingkai Li