Patents by Inventor Wei Zhuang
Wei Zhuang 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: 20070238203Abstract: A method of monitoring synthesis of PCMO precursor solutions includes preparing a PCMO precursor solution and withdrawing samples of the precursor solution at intervals during a reaction phase of the PCMO precursor solution synthesis. The samples of the PCMO precursor solution are analyzed by UV spectroscopy to determine UV transmissivity of the samples of the PCMO precursor solution and the samples used to form PCMO thin films. Electrical characteristics of the PCMO thin films formed from the samples are determined to identify PCMO thin films having optimal electrical characteristics. The UV spectral characteristics of the PCMO precursor solutions are correlated with the PCMO thin films having optimal electrical characteristics. The UV spectral characteristics are used to monitor synthesis of future batches of the PCMO precursor solutions, which will result in PCMO thin films having optimal electrical characteristics.Type: ApplicationFiled: April 11, 2006Publication date: October 11, 2007Inventors: Wei-Wei Zhuang, David Evans, Tingkai Li, Sheng Hsu
-
Publication number: 20070238239Abstract: A method is provided for forming a rare earth element-doped silicon oxide (SiO2) precursor with nanocrystalline (nc) Si particles. In one aspect the method comprises: mixing Si particles into a first organic solvent, forming a first solution with a first boiling point; filtering the first solution to remove large Si particles; mixing a second organic solvent having a second boiling point, higher than the first boiling point, to the filtered first solution; and, fractionally distilling, forming a second solution of nc Si particles. The Si particles are formed by immersing a Si wafer into a third solution including hydrofluoric (HF) acid and alcohol, applying an electric bias, and forming a porous Si layer overlying the Si wafer. Then, the Si particles are mixed into the organic solvent by depositing the Si wafer into the first organic solvent, and ultrasonically removing the porous Si layer from the Si wafer.Type: ApplicationFiled: September 12, 2005Publication date: October 11, 2007Inventors: Wei-Wei Zhuang, Yoshi Ono, Sheng Teng-Hsu, Tingkai Li
-
Publication number: 20070221975Abstract: A multi-layer PrxCa1-xMnO3 (PCMO) thin film capacitor and associated deposition method are provided for forming a bipolar switching thin film. The method comprises: forming a bottom electrode; depositing a nanocrystalline PCMO layer; depositing a polycrystalline PCMO layer; forming a multi-layer PCMO film with bipolar switching properties; and forming top electrode overlying the PCMO film. If the polycrystalline layers are deposited overlying the nanocrystalline layers, a high resistance can be written with narrow pulse width, negative voltage pulses. The PCMO film can be reset to a low resistance using a narrow pulse width, positive amplitude pulse. Likewise, if the nanocrystalline layers are deposited overlying the polycrystalline layers, a high resistance can be written with narrow pulse width, positive voltage pulses, and reset to a low resistance using a narrow pulse width, negative amplitude pulse.Type: ApplicationFiled: May 22, 2007Publication date: September 27, 2007Inventors: Tingkai Li, Lawrence Charneski, Wei-Wei Zhuang, David Evans, Sheng Hsu
-
Patent number: 7271081Abstract: A method is provided for forming a metal/semiconductor/metal (MSM) current limiter and resistance memory cell with an MSM current limiter. The method includes the steps of: providing a substrate; forming an MSM bottom electrode overlying the substrate; forming a ZnOx semiconductor layer overlying the MSM bottom electrode, where x is in the range between about 1 and about 2, inclusive; and, forming an MSM top electrode overlying the semiconductor layer, The ZnOx semiconductor can be formed through a number of different processes such as spin-coating, direct current (DC) sputtering, radio frequency (RF) sputtering, metalorganic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD).Type: GrantFiled: August 31, 2005Date of Patent: September 18, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Tingkai Li, Sheng Teng Hsu, Wei-Wei Zhuang, David R. Evans
-
Patent number: 7256429Abstract: 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: GrantFiled: December 21, 2005Date of Patent: August 14, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Sheng Teng Hsu, Tingkai Li, Fengyan Zhang, Wei Pan, Wei-Wei Zhuang, David R. Evans, Masayuki Tajiri
-
Patent number: 7235407Abstract: A multi-layer PrxCa1-xMnO3 (PCMO) thin film capacitor and associated deposition method are provided for forming a bipolar switching thin film. The method comprises: forming a bottom electrode; depositing a nanocrystalline PCMO layer; depositing a polycrystalline PCMO layer; forming a multi-layer PCMO film with bipolar switching properties; and, forming top electrode overlying the PCMO film. If the polycrystalline layers are deposited overlying the nanocrystalline layers, a high resistance can be written with narrow pulse width, negative voltage pulses. The PCMO film can be reset to a low resistance using a narrow pulse width, positive amplitude pulse. Likewise, if the nanocrystalline layers are deposited overlying the polycrystalline layers, a high resistance can be written with narrow pulse width, positive voltage pulses, and reset to a low resistance using a narrow pulse width, negative amplitude pulse.Type: GrantFiled: May 27, 2004Date of Patent: June 26, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Tingkai Li, Lawrence J. Charneski, Wei-Wei Zhuang, David R. Evans, Sheng Teng Hsu
-
Patent number: 7214583Abstract: Asymmetrically structured memory cells and a fabrication method are provided. The method comprises: forming a bottom electrode; forming an electrical pulse various resistance (EPVR) first layer having a polycrystalline structure over the bottom electrode; forming an EPVR second layer adjacent the first layer, with a nano-crystalline or amorphous structure; and, forming a top electrode overlying the first and second EPVR layers. EPVR materials include CMR, high temperature super conductor (HTSC), or perovskite metal oxide materials. In one aspect, the EPVR first layer is deposited with a metalorganic spin coat (MOD) process at a temperature in the range between 550 and 700 degrees C. The EPVR second layer is formed at a temperature less than, or equal to the deposition temperature of the first layer. After a step of removing solvents, the MOD deposited EPVR second layer is formed at a temperature less than, or equal to the 550 degrees C.Type: GrantFiled: May 16, 2005Date of Patent: May 8, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Sheng Teng Hsu, Tingkai Li, David R. Evans, Wei-Wei Zhuang, Wei Pan
-
Patent number: 7193267Abstract: Resistive cross-point memory devices are provided, along with methods of manufacture and use. The memory devices are comprised by an active layer of resistive memory material interposed between upper electrodes and lower electrodes. A bit region located within the resistive memory material at the cross-point of an upper electrode and a lower electrode has a resistivity that can change through a range of values in response to application of one, or more, voltage pulses. Voltage pulses may be used to increase the resistivity of the bit region, decrease the resistivity of the bit region, or determine the resistivity of the bit region. A diode is formed between at the interface between the resistive memory material and the lower electrodes, which may be formed as doped regions. The resistive cross-point memory device is formed by doping lines within a substrate one polarity, and then doping regions of the lines the opposite polarity to form diodes.Type: GrantFiled: October 21, 2004Date of Patent: March 20, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Sheng Teng Hsu, Wei Pan, Wei-Wei Zhuang
-
Patent number: 7192792Abstract: Resistive cross point memory devices are provided, along with methods of manufacture and use, including a method of changing an electrically programmable resistance cross point memory bit. The memory device comprises an active layer of perovskite material interposed between upper electrodes and lower electrodes. A bit region located within the active layer at the cross point of an upper electrode and a lower electrode has a resistivity that can change through a range of values in response to application of one, or more voltage pulses. Voltage pulses may be used to increase the resistivity of the bit region, decrease the resistivity of the bit region, or determine the resistivity of the bit region. Memory circuits are provided to aid in the programming and read out of the bit region.Type: GrantFiled: February 24, 2005Date of Patent: March 20, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Sheng Teng Hsu, Wei-Wei Zhuang
-
Publication number: 20070054042Abstract: A method of SrCu2O2 spin-on precursor synthesis and low temperature p-type thin film deposition, includes preparing a wafer to receive a spin-coating thereon; selecting metalorganic compounds to form a SrCu2O2 precursor, mixing and refluxing the metalorganic compounds to form a precursor mixture; filtering the precursor mixture to produce a spin-coating precursor; applying the spin-coating precursor to the wafer in a two-step spin coating procedure; baking the spin-coated wafer using a hot-plate bake to evaporate substantially all of the solvents; and annealing the spin-coated wafer to form a SrCu2O2 layer thereon in a two-step post-anneal process.Type: ApplicationFiled: September 6, 2005Publication date: March 8, 2007Inventors: Wei-Wei Zhuang, Yoshi Ono, Wei Gao
-
Publication number: 20070048990Abstract: A method of buffer layer formation for RRAM thin film deposition includes preparing a substrate; depositing a bottom electrode on the substrate; depositing a thin layer of a transition metal having a multiple valence on the bottom electrode; depositing a layer of metal oxide on the transition metal; depositing a top electrode on the metal oxide; annealing the substrate and the layers formed thereon; and completing the RRAM.Type: ApplicationFiled: August 30, 2005Publication date: March 1, 2007Inventors: Wei-Wei Zhuang, Sheng Hsu, David Evans, Tingkai Li, Lawrence Charneski
-
Patent number: 7166485Abstract: A superlattice nanocrystal Si—SiO2 electroluminescence (EL) device and fabrication method have been provided. The method comprises: providing a Si substrate; forming an initial SiO2 layer overlying the Si substrate; forming an initial polysilicon layer overlying the initial SiO2 layer; forming SiO2 layer overlying the initial polysilicon layer; repeating the polysilicon and SiO2 layer formation, forming a superlattice; doping the superlattice with a rare earth element; depositing an electrode overlying the doped superlattice; and, forming an EL device. In one aspect, the polysilicon layers are formed by using a chemical vapor deposition (CVD) process to deposit an amorphous silicon layer, and annealing. Alternately, a DC-sputtering process deposits each amorphous silicon layer, and following the forming of the superlattice, polysilicon is formed by annealing the amorphous silicon layers. Silicon dioxide can be formed by either thermal annealing or by deposition using a DC-sputtering process.Type: GrantFiled: July 5, 2005Date of Patent: January 23, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Tingkai Li, Sheng Teng Hsu, Wei-Wei Zhuang
-
Publication number: 20070015329Abstract: A method is provided for forming a metal/semiconductor/metal (MSM) current limiter and resistance memory cell with an MSM current limiter. The method comprises: providing a substrate; forming an MSM bottom electrode overlying the substrate; forming a ZnOx semiconductor layer overlying the MSM bottom electrode, where x is in the range between about 1 and about 2, inclusive; and, forming an MSM top electrode overlying the semiconductor layer. The ZnOx semiconductor can be formed through a number of different processes such as spin-coating, direct current (DC) sputtering, radio frequency (RF) sputtering, metalorganic chemical vapor deposition (MOCVD), or atomic layer deposition (ALD).Type: ApplicationFiled: August 31, 2005Publication date: January 18, 2007Inventors: Tingkai Li, Sheng Hsu, Wei-Wei Zhuang, David Evans
-
Publication number: 20070010037Abstract: A superlattice nanocrystal Si—SiO2 electroluminescence (EL) device and fabrication method have been provided. The method comprises: providing a Si substrate; forming an initial SiO2 layer overlying the Si substrate; forming an initial polysilicon layer overlying the initial SiO2 layer; forming SiO2 layer overlying the initial polysilicon layer; repeating the polysilicon and SiO2 layer formation, forming a superlattice; doping the superlattice with a rare earth element; depositing an electrode overlying the doped superlattice; and, forming an EL device. In one aspect, the polysilicon layers are formed by using a chemical vapor deposition (CVD) process to deposit an amorphous silicon layer, and annealing. Alternately, a DC-sputtering process deposits each amorphous silicon layer, and following the forming of the superlattice, polysilicon is formed by annealing the amorphous silicon layers. Silicon dioxide can be formed by either thermal annealing or by deposition using a DC-sputtering process.Type: ApplicationFiled: July 5, 2005Publication date: January 11, 2007Inventors: Tingkai Li, Sheng Hsu, Wei-Wei Zhuang
-
Patent number: 7157287Abstract: A method of fabricating a CMR thin film for use in a semiconductor device includes preparing a CMR precursor in the form of a metal acetate based acetic acid solution; preparing a wafer; placing a wafer in a spin-coating chamber; spin-coating and heating the wafer according to the following: injecting the CMR precursor into a spin-coating chamber and onto the surface of the wafer in the spin-coating chamber; accelerating the wafer to a spin speed of between about 1500 RPM to 3000 RPM for about 30 seconds; baking the wafer at a temperature of about 180° C. for about one minute; ramping the temperature to about 230° C.; baking the wafer for about one minute at the ramped temperature; annealing the wafer at about 500° C. for about five minutes; repeating said spin-coating and heating steps at least three times; post-annealing the wafer at between about 500° C. to 600° C. for between about one to six hours in dry, clean air; and completing the semiconductor device.Type: GrantFiled: May 27, 2004Date of Patent: January 2, 2007Assignee: Sharp Laboratories of America, Inc.Inventors: Wei-Wei Zhuang, Tingkai Li, Wei Pan, David R. Evans, Sheng Teng Hsu
-
Patent number: 7141481Abstract: 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: GrantFiled: July 29, 2004Date of Patent: November 28, 2006Assignee: Sharp Laboratories of America, Inc.Inventors: Sheng Teng Hsu, Wei-Wei Zhuang, Wei Pan, Fengyan Zhang
-
Publication number: 20060246606Abstract: A method of fabricating resistor memory array includes preparing a silicon substrate; depositing a bottom electrode, a sacrificial layer, and a hard mask layer on a substrate P+ layer; masking, patterning and etching to remove, in a first direction, a portion of the hard mask, the sacrificial material, the bottom electrode; depositing a layer of silicon oxide; masking, patterning and etching to remove, in a second direction perpendicular to the first direction, a portion of the hard mask, the sacrificial material, the bottom electrode;, and over etching to an N+ layer and at least 100 nm of the silicon substrate; depositing of a layer of silicon oxide; etching to remove any remaining hard mask and any remaining sacrificial material; depositing a layer of CMR material; depositing a top electrode; applying photoresist, patterning the photoresist and etching the top electrode; and incorporating the memory array into an integrated circuit.Type: ApplicationFiled: May 2, 2005Publication date: November 2, 2006Inventors: Sheng Hsu, Jong-Jan Lee, Jer-Shen Maa, Douglas Tweet, Wei-Wei Zhuang
-
Publication number: 20060214172Abstract: A nanotip electroluminescence (EL) diode and a method are provided for fabricating said device. The method comprises: forming a plurality of Si nanotip diodes; forming a phosphor layer overlying the nanotip diode; and, forming a top electrode overlying the phosphor layer. The nanotip diodes are formed by: forming a Si substrate with a top surface; forming a Si p-well; forming an n+ layer of Si, having a thickness in the range of 30 to 300 nanometers (nm) overlying the Si p-well; forming a reactive ion etching (RIE)-induced polymer grass overlying the substrate top surface; using the RIE-induced polymer grass as a mask, etching areas of the substrate not covered by the mask; and, forming the nanotip diodes in areas of the substrate covered by the mask.Type: ApplicationFiled: March 23, 2005Publication date: September 28, 2006Inventors: Sheng Hsu, Tingkai Li, Wei-Wei Zhuang
-
Publication number: 20060194403Abstract: PrCaMnO (PCMO) thin films with predetermined memory-resistance characteristics and associated formation processes have been provided. In one aspect the method comprises: forming a Pr3+1?xCa2+xMnO thin film composition, where 0.1<x<0.6; in response to the selection of x, varying the ratio of Mn and O ions as follows: O2? (3±20%); Mn3+ ((1?x)±20%); and, Mn4+ (x±20%). When the PCMO thin film has a Pr3+0.70Ca2+0.30Mn3+0.78Mn4+0.22O2?2.96 composition, the ratio of Mn and O ions varies as follows: O2? (2.96); Mn3+ ((1?x)+8%); and, Mn4+ (x?8%). In another aspect, the method creates a density in the PCMO film, responsive to the crystallographic orientation. For example, if the PCMO film has a (110) orientation, a density is created in the range of 5 to 6.76 Mn atoms per 100 ?2 in a plane perpendicular to the (110) orientation.Type: ApplicationFiled: March 17, 2006Publication date: August 31, 2006Inventors: Tingkai Li, Wei-Wei Zhuang, David Evans, Sheng Hsu
-
Patent number: 7098043Abstract: A Pr1-XCaXMnO3 (PCMO) spin-coat deposition method for eliminating voids is provided, along with a void-free PCMO film structure. The method comprises: forming a substrate, including a noble metal, with a surface; forming a feature, such as a via or trench, normal with respect to the substrate surface; spin-coating the substrate with acetic acid; spin-coating the substrate with a first, low concentration of PCMO solution; spin-coating the substrate with a second concentration of PCMO solution, having a greater concentration of PCMO than the first concentration; baking and RTA annealing (repeated one to five times); post-annealing; and, forming a PCMO film with a void-free interface between the PCMO film and the underlying substrate surface. The first concentration of PCMO solution has a PCMO concentration in the range of 0.01 to 0.1 moles (M). The second concentration of PCMO solution has a PCMO concentration in the range of 0.2 to 0.5 M.Type: GrantFiled: January 15, 2004Date of Patent: August 29, 2006Assignee: Sharp Laboratories of America, Inc.Inventors: Wei-Wei Zhuang, Lisa H. Stecker, Gregory M. Stecker, Sheng Teng Hsu