Showing papers on "Graphene oxide paper published in 2003"

Lanthanide oxide / hafnium oxide dielectric layers

Abstract: Dielectric layers containing an atomic layer deposited hafnium oxide and an electron beam evaporated lanthanide oxide and a method of fabricating such a dielectric layer produce a reliable dielectric layer having an equivalent oxide thickness thinner than attainable using SiO 2 . Forming a layer of hafnium oxide by atomic layer deposition and forming a layer of a lanthanide oxide by electron beam evaporation, where the layer of hafnium oxide is adjacent and in contact with the layer of lanthanide, provides a dielectric layer with a relatively high dielectric constant as compared with silicon oxide. The dielectric can be formed as a nanolaminate of hafnium oxide and a lanthanide oxide.

Structural Analogies and Differences Between Graphite Oxide and C60 and C70 Polymeric Oxides (Fullerene Ozopolymers)

Abstract: A brief survey of the chemical structural analogies and differences between graphite oxide and fullerene ozopolymers or polymeric fullerene oxides (PFO) is presented. Graphite oxide is the product of oxidation of graphite prepared with strong oxidizing agents while PFO is the products formed by prolonged ozonation of C60 or C70 in solution. Notwithstanding the different starting substrates and oxidation conditions, elemental analyses, FT‐IR spectroscopy and 13C‐NMR spectroscopy suggest a very similar chemical structure for graphite oxide and PFO. A further analogy is the possibility to perform reduction or oxidation reactions on both substrates considered. Graphite oxide and PFO have also in common the ability to act as ion exchangers and as metal ion binders. Even the thermal behavior is comparable. However, X‐ray powder diffraction has confirmed that graphite oxide still has a layered structure derived from graphite but with the graphene sheets at much bigger distance from each other due to the...

Gate dielectric and method therefor

Abstract: A transistor device (10) has a gate dielectric (14) with at least two layers in which one (24 or 26 or 30) is hafnium oxide and the other (24, 26, 28 or 32) is a metal oxide different from hafnium oxide. Both the hafnium oxide and themetal oxide also have a high dielectric constant. The metal oxide provides an interface with the hafnium oxide that operates as a barrier for contaminant penetration. Of particular concern is boron penetration from a polysilicon gate through hafnium oxide to a semiconductor substrate. The hafnium oxide will often have grain boundaries in its crystalline structure that provide a path for boron atoms. The metal oxide has a different structure than that of the hafnium oxide so that those paths for boron in the hafnium oxide are blocked by the metal oxide. Thus, a high dielectric constant is provided while preventing boron penetration from the gate electrode to the substrate.

Carbonate-Melt Oxidized Iridium Wire for pH Sensing

Abstract: A new approach to the preparation of an iridium oxide film for pH sensing is demonstrated. A thick, uniform and dense ceramic oxide layer was grown on the surface of an iridium wire by oxidizing the wire in a molten alkali metal carbonate at high temperature. The alkali metal ion from the carbonate melt was incorporated into the oxide, resulting in a highly stable oxide compound. After treated in acid solution, the oxide layer became hydrated. SEM, XRD, TGA and element analysis were carried out to characterize the oxide film, and a possible formula of the oxide was computed as Li0.86IrO2.34(OH)0.76⋅0.39H2O. The electrode made with this new type of oxide film exhibited good pH sensitivity and stability, even in strong acid/base solutions, or in strong corrosive solution such as hydrofluoric acid. Furthermore, the electrode showed excellent long-term stability over the test period of two and a half years. In addition, individual electrodes prepared from the same batch exhibited remarkable agreement with respect to potential/pH slopes and apparent standard electrode potentials. The performance of the electrodes depends on the properties of the oxide film, such as composition, hydration state and oxidation state.

Method for manufacturing zinc oxide semiconductors

Abstract: Disclosed herein is a method for manufacturing a zinc oxide semiconductor. The method comprises the steps of forming a zinc oxide thin film including a group V element as a dopant on a substrate by using a zinc oxide compound containing a group V element or an oxide thereof, charging the substrate having the zinc oxide thin film formed thereon into a chamber for thermal annealing, and thermal annealing the substrate in the chamber to activate the dopant, thereby changing the zinc oxide thin film exhibiting n-type electrical properties or insulator properties to a zinc oxide thin film exhibiting p-type electrical properties. According to the method, since a zinc oxide thin film exhibiting n-type electrical properties can be easily changed to a zinc oxide thin film exhibiting p-type electrical properties, the provision of holes required for optical devices is facilitated, thereby enabling the development of photoelectric devices such as light-emitting diodes, laser diodes and UV sensors and further extending applicability of the zinc oxide semiconductor.

Synthesis of tungsten oxide on copper surfaces by electroless deposition

Abstract: Tungsten oxide films were successfully synthesized by electroless deposition on copper substrates from tungsten-peroxo electrolytes. The reducing electrons were provided by the copper substrate during oxidation to CuO. Mesoporous tungsten oxide was also fabricated by this method using SDS as a templating agent. This method can be used to fabricate molybdenum oxide, niobium oxide, zirconium oxide, and titanium oxide from metal-peroxo electrolytes.

Method for forming nitrided tunnel oxide layer

Abstract: A method for forming a nitrided tunnel oxide layer is described. A silicon oxide layer as a tunnel oxide layer is formed on a semiconductor substrate, and a plasma nitridation process is performed to implant nitrogen atoms into the silicon oxide layer. A thermal drive-in process is then performed to diffuse the implanted nitrogen atoms across the silicon oxide layer.

Surface characteristics and adhesion performance of black oxide coated copper substrates with epoxy resins

Abstract: Black oxide is a conversion coating applied onto the copper substrate to improve its interfacial adhesion with polymeric adhesives. A comprehensive study is made to characterize the black oxide coating using various characterization techniques, including SEM, XPS, AFM, XRD, Auger electron spectroscopy, TEM, D-SIMS, RBS and contact angle measurements. It was found that the oxide coating consisted of cupric and cuprous oxide layers from the top surface to inside. The cuprous oxide layer was formed on the copper crystal surface, on which densely-packed fibrillar cupric oxide grew continuously until saturation. The cupric oxide had a fibrillar structure with high roughness at the nanoscopic scale, whereas the cuprous oxide was rather flat and granular. There was a continuous change in oxide composition with no distinct boundary between the two oxide layers. The bond strength between the epoxy resin and the oxide coated copper substrate increased rapidly at a low level of oxide thickness, and became saturated ...

Zinc oxide nanoparticle and method for manufacturing the same, zinc oxide nanoparticle-containing composition and laminate using the same

Abstract: [Object] To provide zinc oxide nanoparticles which are ultrafine particles, whose cohesiveness is suppressed, and which are stable against light, heat, oxygen, etc., a method for producing the same, a composition containing the zinc oxide nanoparticles, and A laminate using the same is provided. A zinc oxide nanoparticle in which the surface of a zinc oxide crystal particle is covered with a phase having a silicon oxide composition, wherein the total content of sulfur, phosphorus, and nitrogen atoms is based on the total weight of the nanoparticle. 50 ppm or less, and the Z-average particle diameter is 3 to 50 nm, or as a 1% by weight ethanol dispersion liquid, after standing at 23 ° C. for 3 days at an optical path length of 10 mm at a wavelength of 400 nm. In a liquid phase containing zinc oxide nanoparticles having a light transmittance of 90% or more and zinc oxide crystal particles, an alkoxysilane is hydrolyzed in the presence of water and a basic organic compound having no active hydrogen. A method for producing zinc oxide nanoparticles covering a surface of zinc oxide crystal particles with a phase having a silicon oxide composition generated by a silanol condensation reaction of the hydrolyzate of the hydrolyzate, and the zinc oxide nanoparticles Yes composition and laminate using the same. [Selection diagram] None

Semiconductor device containing oxide/nitride/oxide dielectric layer and method of forming the same

Abstract: A semiconductor device and a method of forming the semiconductor device are disclosed. The semiconductor device includes: a semiconductor substrate; a patterned floating gate formed on the semiconductor substrate, the patterned floating gate having upper and side parts and corners; and a dielectric layer containing a first oxide layer, a nitride layer and a second oxide layer deposited over the semiconductor substrate and the floating gate. The ratio of the thickness of the first oxide layer in the upper and side parts of the patterned floating gate to the thickness of the first oxide layer in the corners of the patterned floating gate does not exceed 1.4. The semiconductor device has an improved coupling coefficient, and reduced leakage current.

Conductive titanium oxide sintered compact, sputtering target, translucent member, and image display device

Abstract: PROBLEM TO BE SOLVED: To solve the problems, such as stability of a sputter rate and the degradation in refractive index with visible light while a method of obtaining conductivity by firing a titanium oxide compact to be sintered in a nonoxidizing atmosphere to give rise to an oxygen defect and a method of adding indium oxide, zinc oxide, etc., as dopants to the titanium oxide compact to be sintered and subjecting the same to oxidation firing are devised as a method for manufacturing the conductive titanium oxide sintered compact. SOLUTION: The conductive titanium oxide sintered compact containing titanium oxide as a principal component and containing at least one kind selected from niobium oxide and tantalum oxide as a dopant contains at least one kind selected from indium oxide, tin oxide, zinc oxide, gallium oxide, and aluminum oxide. COPYRIGHT: (C)2005,JPO&NCIPI

Electrical behavior of semiconducting nanopowders versus environment

Abstract: When applied to the study of semiconducting nanosized particles, Fourier transform infrared spectroscopy allows the simultaneous analysis of the chemical reactions occurring at the nanoparticle surface and the resultant variations of the electrical conductivity. This technique has been used to compare the sensing potentiality of three semiconductors (tin oxide, indium oxide and tungsten oxide nanoparticles) before they are integrated in the fabrication process of actual gas sensors. It has been found that the sensitivity to CO of tin oxide and indium oxide nanoparticles is fairly good, whereas that of tungsten oxide is quasi nil. However, tungsten oxide, like indium oxide, is very sensitive to oxygen and reducing treatments. The presence of humidity irreversibly affects the response of tin oxide to CO and oxygen, whereas that of indium and tungsten oxides to both gases seems to be relatively independent from the moisture content. It is generally observed that a higher operating temperature leads to a more stable baseline and a faster response. Moreover, the formation of surface carbonate groups observed in several cases under CO adsorption does not imply a larger response, thus confirming that the carbonate formation is not a significant factor in the CO detection mechanism.

Oxide film forming method, the oxide film forming apparatus and an electronic device material

Abstract: PROBLEM TO BE SOLVED: To provide an oxide film forming method and an oxide film forming apparatus capable of easily controlling the film thickness of an oxide film and supplying an oxide film of excellent quality, and an electronic device material having such the oxide film of the excellent quality. SOLUTION: In the presence of a treating gas containing at least oxygen and hydrogen, the surface of a base material for an electronic device is irradiated with plasmas based on the oxygen and the hydrogen and the oxide film is formed on the surface of the base material for the electronic device. COPYRIGHT: (C)2005,JPO&NCIPI

Method of passing electric current through highly resistive anodic oxide films

Abstract: The metal oxide surface coating of an anodized valve metal may be made conductive under certain conditions so that conductive coatings can be electrolytically deposited on the surface of the oxide. When a dry polar aprotic electrolyte solution is used at a reduced temperature and a relatively high field is applied, the oxide ceases to be insulative. The process is reversible, meaning that there is no permanent change in the oxide.

Method for forming oxide film and electronic device material

Abstract: An oxide film is formed on a surface of a substrate for electronic device by irradiating the surface of the substrate for an electronic device with a plasma, which is produced from oxygen and hydrogen, in the presence of a treating gas containing at least oxygen and hydrogen. A method and apparatus for forming an oxide film, wherein control of the thickness of the oxide film is easy and an oxide film of good quality can be obtained, and a material for an electronic device having such a good-quality oxide film are disclosed.

Method for the production of a metal oxide powder or a semiconductor oxide powder, oxide powder, solid body, and the use thereof

Abstract: The invention relates to a method for producing nanostructured mixed oxide having a high electrical conductivity, e.g. indium tin oxide, as well as an oxide powder, a solid body, and the use thereof as a sputter target. The oxide is produced by continuous direct oxidation, a metal material or semiconductor material being used as a smelting electrode in an oxygen plasma. The synthesis reaction is triggered at a very high temperature, followed by a thermal state which is controlled in such a way that an error-free crystalline structure allowing high mobility of electrical charges is created.

Metal graphite material and manufacturing method therefor

Abstract: PROBLEM TO BE SOLVED: To provide a metal graphite material for a brush or the like that hardly receives damage caused by spark discharge and is useful for reducing an electric noise level when the spark discharge is generated, and to provide a manufacturing method for the metal graphite material. SOLUTION: In the metal graphite material formed of an aggregate of graphite particles mainly composed of graphite and copper, groups of copper fine particles are supported on surfaces of the graphite particles, and the size of the copper fine particle is 5 to 100 nanometers. The manufacturing method for the metal graphite material includes steps for: applying a solution including copper complex salt to the surface of the graphite particle and forming a film on the surface of the graphite particle; baking a molded body formed of the aggregate of the graphite particles in an oxygen-contained atmosphere; and thereafter, manufacturing the metal graphite material by heating the molded body in a reducing atmosphere. COPYRIGHT: (C)2005,JPO&NCIPI

Growth of Tailored Oxide Nanostructures for Use as Catalyst Support Media

Abstract: Graphite nanofibers are a family of materials consisting of graphene sheets arranged at various angles with respect to the growth axis. Graphite nanofibers possessing a structure in which the individual sheets constituting the material are aligned in a direction perpendicular to the growth axis have been used as templates for the deposition of selected metal oxides. The abundant number of exposed edges in the substrate act as collection centers onto which the chemical vapor deposited oxides nucleate and grow in an epitaxial manner. When the mixed oxide/graphite nanofiber structure is treated in CO 2 at 1100 °C, it is possible to selectively remove the carbon skeleton so that one is left with a highly crystalline metal oxide faceted nanotube. Electron diffraction and X-ray diffraction studies demonstrate that these oxides adopt preferred orientations that are quite different from those encountered with the corresponding oxide powders, which are generally amorphous in nature. These novel oxide structures provide a well-ordered surface on which to disperse small metal particles for subsequent use as catalysts. Preliminary results indicate that when iron is supported on the graphite nanofiber-modified alumina surface, the catalytic behavior of the system is significantly different from that observed when the metal is dispersed directly onto the nanofibers or the oxide powder. This effect is discussed in terms of the possibility that the metal particles adopt a preferred crystallographic orientation on the oxide nanotube surface, which favor interaction with certain gas-phase molecules.

Controlled Structure of Gallium Oxide and Indium Oxide Nanowires

Abstract: Gallium oxide (Ga2O3) and indium oxide (In2O3) nanostructures were synthesized by chemical vapor deposition (CVD). Ga2O3 nanowires were synthesized using Ga/Ga2O3 mixture and O2. The diameter of the nanowires is 30–80 nm with an average value of 50 nm. They are consisted of single-crystalline monoclinic crystal. While the nanowires grown without catalyst exhibit a significant planar defect, the nanowires grown with nickel catalytic nanoparticles are almost defect-free. The growth direction of the nanowires grown without the catalyst is uniformly [010]. In contrast, the nanowires grown with the catalyst have random growth direction. X-ray diffraction, Raman spectroscopy, and photoluminescence are well correlated with the structural characteristics of the nanowires. The result provides an evidence for the catalyst effect in controlling the structure of nanowires. In2O3 nanostructures were also synthesized in a controlled manner by selecting the catalyst. The reactants were In and In/In2O3 mixture. The nanowires were produced using catalytic Au nanoparticles and Ga. But the unique bifurcated-structure nanobelts were instead grown without Ga. The nanowires have uniform [100] growth direction with rectangular cross-section. We converted the In2O3 nanowires to In2O3-Ga2O3 nanostructures.

Synthesis and characterization of poly acrylic acid／graphite oxide nanocomposite

Abstract: Acrylic acid-intercalated graphite oxide and poly acrylic acid (PAA)-intercalated graphite oxide were prepared and characterized by X-Ray diffraction (XRD), Fourier transform infrared spectra (FTIR) and high resolution electronic microscope (HREM). Results show that the intercalation process is not only a physical diffusion process but also mainly a chemical reaction process. The high resolution electronic microscope results also reveal that the Ic value of PAA-intercalated graphite oxide (GO) could change widely from 1.6nm to 4.0nm.

Methods for preserving strained semiconductor layers during oxide layer formation

Abstract: Oxidation methods, which avoid consuming undesirably large amounts of surface material in Si/SiGe heterostructure-based wafers, replace various intermediate CMOS thermal oxidation steps. First, by using oxide deposition methods, arbitrarily thick oxides may be formed with little or no consumption of surface silicon. These oxides, such as screening oxide and pad oxide, are formed by deposition onto, rather than reaction with and consumption of the surface layer. Alternatively, oxide deposition is preceded by a thermal oxidation step of short duration, e.g., rapid thermal oxidation. Here, the short thermal oxidation consumes little surface Si, and the Si/oxide interface is of high quality. The oxide may then be thickened to a desired final thickness by deposition. Furthermore, the thin thermal oxide may act as a barrier layer to prevent contamination associated with subsequent oxide deposition.

Process for producing bismuth-containing oxide films

Abstract: A process for producing bismuth-containing oxide thin films by Atomic Layer Deposition, including using an organic bismuth compound having at least one silylamido ligand as a source material for the bismuth oxide. Bismuth-containing oxide thin films produced by the preferred embodiments can be used, for example, as ferroelectric or dielectric material in integrated circuits and/or as superconductor materials.

Use of metal oxide masks for treating surfaces in the production of microchips

Abstract: The invention relates to a method for modifying a semiconductor section by section. For doping purposes, the sections that for example are to remain undoped, are masked by a metal oxide, e.g. aluminium oxide (6). The semiconductor is subsequently doped, e.g. from a gas phase, in those sections (7) that have not been covered by the aluminium oxide. The aluminium oxide is then selectively removed, for example using hot phosphoric acid, thus leaving sections of the semiconductor surface consisting of silicon, silicon oxide or silicon nitride on the wafer.