Статті в журналах: "Oxide silicium"

1

Hodek, Jiří, Milan Šípek, and Oskar Šlechta. "Permeation and sorption methods for the determination of transport parameters of gases and vapours through flat membranes." Collection of Czechoslovak Chemical Communications 54, no. 11 (1989): 2919–32. http://dx.doi.org/10.1135/cccc19892919.

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New relations were derived for the determination of diffusion coefficients, coefficients of permeability, and sorption coefficients of gases and vapours through flat membranes by means of the permeation and sorption methods. To verify these relations, a polyurethane filled with silicium oxide (Silica) was chosen as a model system. Transport parameters of water vapours at the temperature of 25 °C were determined of this system by the sorption and permeation methods. Both the methods yield practically the same transport parameters especially after evacuating the membrane before the measurement by the permeation technique.

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2

Lima, N. M. O., Crislene Rodrigues da Silva Morais, L. M. R. Lima, and A. V. Albuquerque. "Electronic Waste: Characterization of the Glass of Cathode Ray Tube Computer for Making Decorative Pieces by Recycling." Materials Science Forum 727-728 (August 2012): 1525–29. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1525.

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The vigorous industrialization of the modern world and the incorporation of new consumption habits of society made appears electronic waste. This work had as objective to collect and characterize vitreous residues originating from Cathode Ray Tubes or, popularly, "image tubes", identified for the acronym CRT, which integrate computers monitors that will be recycled in the production of handicrafts. For its characterization were used techniques: X-Ray Fluorescence, Granulometric Analysis, X-Ray Diffraction. After analyses it was observed that glasses of the screen and of the funnel presented different chemical compositions, being silicium oxide (SiO2) the component of larger percentage in these glasses, 59.89% and 48.63%, for screen and funnel, respectively. Funnel presented 29.47% of lead oxide (PbO) while this oxide is absent in the screen. Screen presents significant amounts of barium oxide (10.75%) and strontium oxide (7.71%). Vitreous samples X-ray diffractions of residues of the funnel and the screen are to each other similar, presenting an amorphous band that indicates silica presence, with absence of crystalline phases. Through the presented results can be concluded that computer monitors CRTs has potential for be recycled, because present great amounts of SiO2, oxide that forms the vitreous net.

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3

Минаков, А. В., А. С. Лобасов, М. И. Пряжников, Л. С. Тарасова, Н. Я. Василенко та В. Я. Рудяк. "Экспериментальное исследование влияния наночастиц на процессы испарения жидкостей". Журнал технической физики 90, № 1 (2020): 33. http://dx.doi.org/10.21883/jtf.2020.01.48657.61-19.

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Evaporation of nanofluids based on distilled water and the silicium and zirconium dioxides, aluminium oxide as well as the diamond has been experimentally studied. The average diameter of the SiO2 nanoparticles was 25 nm, of the ZrO2 nanoparticles was 105 nm, of the Al2O3 nanoparticles was 43 nm and of the diamond nanoparticles was 5 nm. The synchronous thermoanalyser STA 449 С Jupiter was used in the investigation of the evaporation processes. The dependences of the evaporation rate on the volume concentration of the nanoparticles were obtained as a result of the experimental studies. It was shown that as the nanoparticles volume concentration increases the nanofluids evaporation rates monotonically increase too.

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4

Wedel, B., K. Sugiyama, K. Hiraga, and K. Itagaki. "Zur Kristallchemie des ersten Blei-Zink-Silicium-Telluroxids: PbZn4SiTeO10 / On the Crystal Chemistry of the First Lead Zinc Silicon Tellurium Oxyde PbZn4SiTeO10." Zeitschrift für Naturforschung B 54, no. 4 (April 1, 1999): 469–72. http://dx.doi.org/10.1515/znb-1999-0409.

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Single crystals of the new lead zinc silicon tellurium oxide PbZn4SiTeO10 have been prepared by solid state reaction in air. The compound is colourless and crystallizes in orthorhombic symmetry, space group D162h Pnma, with the cell parameters: a = 6.542 (5), b = 15.624(4), c = 8.280(4) Å, Z = 4. The structure has been determined from a single crystal X-ray study and refined to the conventional values R = 0.032 and wR(F2) = 0.050. Zn2+ and Si4+ show tetrahedral and Te6+ octahedral coordination by O2-.The crystal structure is dominated by a 3∞ [Zn4O10]12- framework with isolated TeO66+ and SiO44+ polyhedra. Pb2+ ions are incorporated in the network. The centres of negative charge of the lone pairs of Pb2+ are estimated by calculations of the Coulomb term of the lattice energy

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5

Shadrin, K. V., Viktoria V. Panteleeva, and А. B. Shein. "Passivation of chromium disilicide in acidic media." Вестник Пермского университета. Серия «Химия» = Bulletin of Perm University. CHEMISTRY 11, no. 3 (2021): 202–11. http://dx.doi.org/10.17072/2223-1838-2021-3-202-211.

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The anodic behavior of CrSi2 electrode in 0,5 M H2SO4, 0,5 M HClO4, 0,5 M HNO3 and 0,5 M HCl solutions has been studied by the methods of polarization, capacitance, and impedance measurements. It has been concluded that in the process of anodic oxidation at potentials from corrosion E to transpassivation E inclusive, an oxide film is formed on the surface of chromium disilicide in the studied media, which is close in composition to SiO2 (with a small content of chromium oxides). The presence of this film on the silicide surface determines its high chemical resistance in the studied solutions. The thickness of the oxide film on CrSi2 has been calculated depending on the potential and composition of the electrolyte. The growth constant of the oxide film has been determined.

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6

Logvinova, Alla, Dmitry Zedgenizov, and Richard Wirth. "Specific Multiphase Assemblages of Carbonatitic and Al-Rich Silicic Diamond-Forming Fluids/Melts: TEM Observation of Microinclusions in Cuboid Diamonds from the Placers of Northeastern Siberian Craton." Minerals 9, no. 1 (January 15, 2019): 50. http://dx.doi.org/10.3390/min9010050.

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The microinclusions in cuboid diamonds from Ebelyakh River deposits (northeastern Siberian craton) have been investigated by FIB/TEM techniques. It was found that these microinclusions have multiphase associations, containing silicates, oxides, carbonates, halides, sulfides, graphite, and fluid phases. The bulk chemical composition of the microinclusions indicates two contrasting growth media: Mg-rich carbonatitic and Al-rich silicic. Each media has their own specific set of daughter phases. Carbonatitic microinclusions are characterized by the presence of dolomite, phlogopite, apatite, Mg, Fe-oxide, KCl, rutile, magnetite, Fe-sulfides, and hydrous fluid phases. Silicic microinclusions are composed mainly of free SiO2 phase (quartz), high-Si mica (phengite), Al-silicate (paragonite), F-apatite, Ca-carbonates enriched with Sr and Ba, Fe-sulfides, and hydrous fluid phases. These associations resulted from the cooling of diamond-forming carbonatitic and silicic fluids/melts preserved in microinclusions in cuboid diamonds during their ascent to the surface. The observed compositional variations indicate different origins and evolutions of these fluids/melts.

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7

Nakamura, Kozo, and Junsuke Tomioka. "Effect of Oxygen Precipitates on the Surface-Precipitation of Nickel on Cz-Silicon Wafers." Solid State Phenomena 108-109 (December 2005): 103–8. http://dx.doi.org/10.4028/www.scientific.net/ssp.108-109.103.

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This paper presents a model for the analysis of the surface nucleation and growth of Ni silicide on silicon wafers contaminated by Ni. The model can additionally be used to characterize the gettering reaction of Ni induced by oxygen precipitates. We also discuss the relation between the surface precipitation of Ni silicide and the gettering ability of oxygen precipitate. The surface precipitation of Ni silicide depends on the total surface area of oxide precipitates. When the total surface area of the oxide precipitates exceeds the critical value, the surface precipitation is rapidly suppressed. Our model can explain the phenomenon of the gettering threshold in the following manner. 1) The gettering of Ni by oxygen precipitates is a reaction-limited process at the interface between oxygen precipitate and silicon, as Sueoka proposed. 2) The residual Ni concentration in this reaction-limited gettering process continuously decreases as the total surface area of the oxide precipitates increases. 3) The surface precipitation of Ni silicide is rapidly suppressed when the residual Ni concentration falls below the critical concentration. Our calculation results correspond well with the experimental results.

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8

Rosales, I., D. Ponce, MJ Garcia-Ramirez, and R. Guardian. "Effect of Chromium Addition on the Cyclic Oxidation Resistance of Pseudo-Binary (Mo,Cr)3 Si Silicide Alloy." High Temperature Materials and Processes 37, no. 9-10 (October 25, 2018): 943–49. http://dx.doi.org/10.1515/htmp-2017-0099.

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AbstractThis paper describes the performance under cyclic oxidation of (Mo,Cr)3 Si compound with different Cr additions for possible coating application. Cyclic oxidation was carried out at 1,000 °C at different intervals during 250 h. Oxidized surface samples were analysed by scanning electron microscope where epitaxial oxide scales were observed mainly in samples with higher Cr content which may provide protection against surface oxidation. X-ray diffraction studies have shown the Cr2O3 and SiO2 formation as the main oxide scale; after analyses, it was found that these oxides are responsible for the best oxidation protection, with 36 at.% Cr being the optimal chromium concentration. At lower chromium concentrations, pest reaction occurred in the oxidized samples at times less than 25 h as a result of the formation of the unstable molybdenum oxide.

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9

Han, Jiesheng, Bo Su, Junhu Meng, Aijun Zhang, and Youzhi Wu. "Microstructure and Composition Evolution of a Fused Slurry Silicide Coating on MoNbTaTiW Refractory High-Entropy Alloy in High-Temperature Oxidation Environment." Materials 13, no. 16 (August 14, 2020): 3592. http://dx.doi.org/10.3390/ma13163592.

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In this paper, the Si-20Cr-20Fe coating was prepared on MoNbTaTiW RHEA by a fused slurry method. The microstructural evolution and compositions of the silicide coating under high-temperature oxidation environment were studied. The results show that the silicide coating could effectively prevent the oxidation of the MoNbTaTiW RHEA. The initial silicide coating had a double-layer structure: a high silicon content layer mainly composed of MSi2 as the outer layer and a low silicon content layer mainly contained M5Si3 as the inner layer. Under high-temperature oxidation conditions, the silicon element diffused from the silicide coating to the RHEA substrate while the oxidation of the coating occurred. After oxidation, the coating was composed of an outer oxide layer and an inner silicide layer. The silicide layer moved toward the inside of the substrate, led to the increase of its thickness. Compared with the initial silicified layer, its structure did not change significantly. The structure and compositions of the oxide layer on the outer surface strongly depended on the oxidation temperature. This paper provides a strategy for protecting RHEAs from oxidation at high-temperature environments.

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10

Hope, GA, and DK Pham. "Platinum Silicide/n-Silicon Photoelectrodes: Properties and Characteristics of the Platinum Silicide Layer." Australian Journal of Chemistry 40, no. 3 (1987): 443. http://dx.doi.org/10.1071/ch9870443.

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The surface analysis of thermally grown platinum silicide layers on single crystal silicon wafers has shown that silicide phase growth can occur for thin films. The depth profile was found to depend upon the temperature at which the silicide was formed, the length of time for which the reaction proceeded and the supply of platinum. The ESCA peaks for Pt and Si were shifted in energy from the elemental values in the silicide layer. A surface oxide, assigned as SiO2 from the Si 2p signal, was detected on all samples. The platinum signal broadened considerably when the silicide layer had been largely removed by sputtering, and appeared to consist of two components.

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11

Hakeem, Abbas Saeed, Sharafat Ali, Thomas Höche, Qasem Ahmed Drmosh, Amir Azam Khan, and Bo Jonson. "Microstructure Evaluation and Impurities in La Containing Silicon Oxynitrides." Nanomaterials 11, no. 8 (July 23, 2021): 1896. http://dx.doi.org/10.3390/nano11081896.

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Oxynitride glasses are not yet commercialised primarily due to the impurities present in the network of these glasses. In this work, we investigated the microstructure and instinctive defects in nitrogen rich La−Si−O−N glasses. Glasses were prepared by heating a powder mixture of pure La metal, Si3N4, and SiO2 in a nitrogen atmosphere at 1650–1800 °C. The microstructure and impurities in the glasses were examined by optical microscopy, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy in conjunction with electron energy-loss spectroscopy. Analyses showed that the glasses contain a small amount of spherical metal silicide particles, mostly amorphous or poorly crystalline, and having sizes typically ranging from 1 µm and less. The amount of silicide was estimated to be less than 2 vol. %. There was no systematic relation between silicide formation and glass composition or preparation temperature. The microstructure examination revealed that the opacity of these nitrogen rich glasses is due to the elemental Si arise from the decomposition reaction of silicon nitride and silicon oxide, at a high temperature above ~1600 °C and from the metallic silicide particles formed by the reduction of silicon oxide and silicon nitride at an early stage of reaction to form a silicide intermetallic with the La metal.

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12

Russkikh, M. A., I. S. Polkovnikov, V. V. Panteleeva, and A. B. Shein. "Passivation on manganese monosilicide in sulfuric acid electrolytes." Вестник Пермского университета. Серия «Химия» = Bulletin of Perm University. CHEMISTRY 10, no. 2 (2020): 221–32. http://dx.doi.org/10.17072/2223-1838-2020-2-221-232.

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Several features of the electrode reactions that occur at the surface of transition metal silicide (high strength metal-silicon bond, the effect of chemical reactions and the formation of passivating oxide films) leading to high interest to intermetallic compounds. Anodic behavior of the MnSi electrode in solutions 0.5 M H2SO4 and 0.05 M H2SO4 + 0.45 M Na2SO4 was studied by polarization and impedance measurements. It was concluded that the surface of manganese silicide is coated with an oxide film similar in composition to SiO2. The thickness and resistivity of the oxide film were calculated depending on potential and concentration of sulfuric acid. Generalization and theoretical explanation of the research results may provide a basis for predicting corrosion resistance of metal-silicon alloys in a wide range of corrosive environments.

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13

Tatsuoka, Hirokazu, Wen Li, Er Chao Meng, Daisuke Ishikawa, and Kaito Nakane. "Syntheses and Structural Control of Silicide, Oxide and Metallic Nano-Structured Materials." Solid State Phenomena 213 (March 2014): 35–41. http://dx.doi.org/10.4028/www.scientific.net/ssp.213.35.

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The structural control and morphological modification of a series of silicide, oxide and Ag metal nanostructures have been further discussed with reviews of nanostructure syntheses, such as CrSi2 nanowire bundles dendrites, MoSi2 nanosheets, α-Fe2O3 nanowires nanobelts, CuO/Cu2O nanowire axial heterostructures, ZrO2/SiOx and CrSi2/SiOx core/shell nanowires. In addition, the syntheses of Ag three-dimensional dendrites, two-dimensional dendrites, two-dimensional fractal structures, particles and nanowires also were discussed. Moreover, the structural and morphological properties of the nanostructures were examined. The structural control and morphological modifications of the nanostructures have been successfully demonstrated by the appropriate thermal treatments with specific starting materials. A large volume of silicide nanowire bundles, large area of oxide nanowire arrays and large area Ag nanostructure coatings were successfully fabricated.

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14

Cheng, Chi-Hsuan, and Cheng-Lun Hsin. "A novel silicide and germanosilicide by NiCo alloy for Si and SiGe source/drain contact with improved thermal stability." CrystEngComm 16, no. 48 (2014): 10933–36. http://dx.doi.org/10.1039/c4ce01465k.

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NiCo (10 at.% of Co) alloy was employed in the formation of metal silicide and germanosilicide as the contact layer which can be used as future complementary metal–oxide–semiconductor source/drain contact.

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15

Li, Meng, Sung Kwen Oh, Hong Sik Shin, and Hi Deok Lee. "Improvement of Thermal Stability of Nickel Silicide Using Co-Sputtering of Ni and Ti on Boron Cluster Implanted Ultra-Shallow Junction for Nanoscale CMOS Technology." Advanced Materials Research 699 (May 2013): 817–21. http://dx.doi.org/10.4028/www.scientific.net/amr.699.817.

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In this paper, Ni-silicide formed by co-sputtering of Ni and Ti on a boron cluster (BF2, B18H22) implanted ultra-shallow source/drain for MOSFET (metal oxide semiconductor field effect transistor) is proposed. Ni and Ti with a TiN capping layer were deposited by co-sputtering on boron cluster implanted wafer. By analysis of its sheet resistance, interfacial structures, surface morphological stability, and phase formation after post-silicidation annealing, thermal stability of Ni-silicide was found to be improved a lot.

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16

Vassilevski, Konstantin, Irina P. Nikitina, Alton B. Horsfall, Nicolas G. Wright, Andrew J. Smith, and C. Mark Johnson. "Silicon Carbide Vertical JFET with Self-Aligned Nickel Silicide Contacts." Materials Science Forum 679-680 (March 2011): 670–73. http://dx.doi.org/10.4028/www.scientific.net/msf.679-680.670.

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Trenched implanted vertical JFETs (TI-VJFETs) with self-aligned gate and source contacts were fabricated on commercial 4H-SiC epitaxial wafers. Gate regions were formed by aluminium implantation through the same silicon oxide mask which was used for etching mesa-structures. Self-aligned nickel silicide source and gate contacts were formed using a silicon oxide spacer formed on mesa-structure sidewalls by anisotropic thermal oxidation of silicon carbide followed by anisotropic reactive ion etching of oxide. Fabricated normally-on 4H-SiC TI-VJFETs demonstrated low gate leakage currents and blocking voltages exceeding 200 V.

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17

K Lam, Lawrence, Nan Jiang, Dieter G Ast, and John Silcox. "TEM Study of Amorphous Silicon Recrystallization." Microscopy and Microanalysis 5, S2 (August 1999): 754–55. http://dx.doi.org/10.1017/s1431927600017098.

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Recently there has been increasing interest in nickel induced lateral recrystallization of amorphous silicon because of its potential to improve device performance and to lower the thermal budget during processing. The hypothesis is that the formation of nickel silicide provides a low energy nucleus for the recrystallization of amorphous silicon. The silicide, moving into a-Si, leaves crystalline silicon behind.1 The grains formed, therefore, tend to elongated. In this paper, we attempt to use TEM to investigate in detail the nickel assisted lateral crystallization of amorphous silicon. The sample was prepared by first depositing a 1000A thick low temperature, oxide layer, LTO, on Corning 1737 glass. A 1000A thick amorphous silicon layer, a-Si, and 1000A thick a-Si were deposited subsequently. The sample was pattern and etched with hydrofluoric acid to form lOum x lOum holes in the oxide layer. Next, 200A of nickel was evaporated onto the sample, followed by a 600°C, 6 hours anneal to induce lateral recrystallization.

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18

Kannan, V. C., S. M. Merchant, R. B. Irwin, A. K. Nanda, M. Sundahl, B. Rambabu, and A. K. Singh. "TEM characterization of WSix films." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 848–49. http://dx.doi.org/10.1017/s0424820100171973.

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Metal silicides such as WSi2, MoSi2, TiSi2, TaSi2 and CoSi2 have received wide attention in recent years for semiconductor applications in integrated circuits. In this study, we describe the microstructures of WSix films deposited on SiO2 (oxide) and polysilicon (poly) surfaces on Si wafers afterdeposition and rapid thermal anneal (RTA) at several temperatures. The stoichiometry of WSix films was confirmed by Rutherford Backscattering Spectroscopy (RBS). A correlation between the observed microstructure and measured sheet resistance of the films was also obtained.WSix films were deposited by physical vapor deposition (PVD) using magnetron sputteringin a Varian 3180. A high purity tungsten silicide target with a Si:W ratio of 2.85 was used. Films deposited on oxide or poly substrates gave rise to a Si:W ratio of 2.65 as observed by RBS. To simulatethe thermal treatments of subsequent processing procedures, wafers with tungsten silicide films were subjected to RTA (AG Associates Heatpulse 4108) in a N2 ambient for 60 seconds at temperatures ranging from 700° to 1000°C.

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19

Bierwagen, Oliver, André Proessdorf, Michael Niehle, Frank Grosse, Achim Trampert, and Max Klingsporn. "Oxygen-Deficient Oxide Growth by Subliming the Oxide Source Material: The Cause of Silicide Formation in Rare Earth Oxides on Silicon." Crystal Growth & Design 13, no. 8 (July 10, 2013): 3645–50. http://dx.doi.org/10.1021/cg400652b.

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20

Sugita, Hajime, Terumi Oguma, Junko Hara, Ming Zhang, and Yoshishige Kawabe. "Effects of Silicic Acid on Leaching Behavior of Arsenic from Spent Magnesium-Based Adsorbents Containing Arsenite." Sustainability 14, no. 7 (April 2, 2022): 4236. http://dx.doi.org/10.3390/su14074236.

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The spent adsorbents left after treating arsenic-contaminated water contain large amounts of arsenic. These spent adsorbents may come into contact with silicic acid leached from soil or cementitious solidification materials in the disposal environment. Thus, it is important to evaluate the effects of silicic acid on spent adsorbents containing arsenic. In this study, the effects of silicic acid on spent Mg-based adsorbents (magnesium oxide (MgO) and magnesium hydroxide (Mg(OH)2)) containing arsenite were investigated. The arsenic leaching ratios of both spent adsorbents decreased slightly with an increase in the initial silicic acid concentration of the eluent. The arsenic leaching ratio decreased from 1.24% to 0.69% for MgO and from 5.97% to 4.71% for Mg(OH)2 at an initial Si-normalized concentration of 100 mg/L. The primary mechanism behind the inhibition of arsenic leaching by silicic acid was determined to be the difficulty of arsenic desorption due to the coating effect following the adsorption of silicic acid species. The results indicate that the arsenic leaching related to the ion exchange reaction with silicic acid hardly occurred for the spent Mg-based adsorbents. Compared with various spent Mg-based and Ca-based adsorbents, the spent MgO adsorbent exhibited the highest environmental stability and best performance.

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21

Lee, Byeong Woo. "Effect of diffusion coatings on the high temperature properties of nickel-chromium-superalloys." International Journal of Modern Physics B 32, no. 19 (July 18, 2018): 1840056. http://dx.doi.org/10.1142/s0217979218400568.

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The halide-activated pack cementation method was utilized to deposit aluminide or silicide coatings on Inconel 617 and Hastelloy X superalloys. Aluminide and silicide diffusion coatings were formed at 850[Formula: see text]C for 2 h in nitrogen atmosphere, using a pack mixture containing pure aluminum (Al) or silicon (Si) and aluminum oxide (Al2O3) powders with activators of NH4Cl and AlF3. Aluminide-coated alloys showed homogeneous and uniform microstructures. Al diffused into the alloy inwards and aluminide diffusion coatings of [Formula: see text]17 [Formula: see text]m thick were formed inside the alloy. It was shown that the Al coatings played a key role in blocking off the excessive corrosion products at a high temperature for the alloys. The enhanced thermal stability and improved wear resistance were achieved in the aluminide coatings. In contrast to the aluminide coating, the silicide coating played a negative role, unable to provide the protective layer. The microstructural evolution and thermal stability of the aluminide- and silicide-coated alloys have been elucidated.

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22

González, Elías, Shoji Kojima, Yoshihiko Ichii, Takayuki Tanaka, Yoshikazu Fujimoto, and Takeyuki Ogata. "Silician Magnetite from the Copiapó Nordeste Prospect of Northern Chile and Its Implication for Ore-Forming Conditions of Iron Oxide–Copper–Gold Deposits." Minerals 8, no. 11 (November 14, 2018): 529. http://dx.doi.org/10.3390/min8110529.

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Silica-bearing magnetite was recognized in the Copiapó Nordeste prospect as the first documented occurrence in Chilean iron oxide–copper–gold (IOCG) deposits. The SiO2-rich magnetite termed silician magnetite occurs in early calcic to potassic alteration zones as orderly oscillatory layers in polyhedral magnetite and as isolated discrete grains, displaying perceptible optical differences in color and reflectance compared to normal magnetite. Micro-X-ray fluorescence and electron microprobe analyses reveal that silician magnetite has a significant SiO2 content with small amounts of other “impure” components, such as Al2O3, CaO, MgO, TiO2, and MnO. The oscillatory-zoned magnetite is generally enriched in SiO2 (up to 7.5 wt %) compared to the discrete grains. The formation of silician magnetite is explained by the exchange reactions between 2Fe (III) and Si (IV) + Fe (II), with the subordinate reactions between Fe (III) and Al (III) and between 2Fe (II) and Ca (II) + Mg (II). Silician magnetite with high concentrations of SiO2 (3.8–8.9 wt %) was similarly noted in intrusion-related magmatic–hydrothermal deposits including porphyry- and skarn-type deposits. This characteristic suggests that a hydrothermal system of relatively high-temperature and hypersaline fluids could be a substantial factor in the formation of silician magnetite with high SiO2 contents.

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23

Leclerc, Gervais, Louis Paquin, and Fabrice Baratay. "Nonlinear silicon oxide growth patterns in a gold-silicon system." Journal of Materials Research 7, no. 9 (September 1992): 2458–64. http://dx.doi.org/10.1557/jmr.1992.2458.

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Oxide films are grown on a silicon wafer at low temperatures through the catalytic action of a thin gold film. Our results indicate that the oxide film thickness and morphology vary with the initial gold film thickness but do not significantly depend on the temperature. A Fourier analysis of the film structure suggests that the growth mechanism may include a spinodal decomposition where a binary alloy undergoes a phase separation. It is argued that gold silicide is the most likely candidate for spinodal decomposition.

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24

Ciobanu, Cristiana L., Max R. Verdugo-Ihl, Ashley Slattery, Nigel J. Cook, Kathy Ehrig, Liam Courtney-Davies, and Benjamin P. Wade. "Silician Magnetite: Si–Fe-Nanoprecipitates and Other Mineral Inclusions in Magnetite from the Olympic Dam Deposit, South Australia." Minerals 9, no. 5 (May 20, 2019): 311. http://dx.doi.org/10.3390/min9050311.

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A comprehensive nanoscale study on magnetite from samples from the outer, weakly mineralized shell at Olympic Dam, South Australia, has been undertaken using atom-scale resolution High Angle Annular Dark Field Scanning Transmission Electron Microscopy (HAADF STEM) imaging and STEM energy-dispersive X-ray spectrometry mapping and spot analysis, supported by STEM simulations. Silician magnetite within these samples is characterized and the significance of nanoscale inclusions in hydrothermal and magmatic magnetite addressed. Silician magnetite, here containing Si–Fe-nanoprecipitates and a diverse range of nanomineral inclusions [(ferro)actinolite, diopside and epidote but also U-, W-(Mo), Y-As- and As-S-nanoparticles] appears typical for these samples. We observe both silician magnetite nanoprecipitates with spinel-type structures and a γ-Fe1.5SiO4 phase with maghemite structure. These are distinct from one another and occur as bleb-like and nm-wide strips along d111 in magnetite, respectively. Overprinting of silician magnetite during transition from K-feldspar to sericite is also expressed as abundant lattice-scale defects (twinning, faults) associated with the transformation of nanoprecipitates with spinel structure into maghemite via Fe-vacancy ordering. Such mineral associations are characteristic of early, alkali-calcic alteration in the iron-oxide copper gold (IOCG) system at Olympic Dam. Magmatic magnetite from granite hosting the deposit is quite distinct from silician magnetite and features nanomineral associations of hercynite-ulvöspinel-ilmenite. Silician magnetite has petrogenetic value in defining stages of ore deposit evolution at Olympic Dam and for IOCG systems elsewhere. The new data also add new perspectives into the definition of silician magnetite and its occurrence in ore deposits.

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25

Topuria, T., N. D. Browning, and Z. Ma. "Characterization of the Source/Drain Region in Mos Devices by Scanning Transmission Electron Microscopy." Microscopy and Microanalysis 7, S2 (August 2001): 210–11. http://dx.doi.org/10.1017/s1431927600027124.

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The advancement of metal-oxide-semiconductor (MOS) technology towards sub- 100nm device dimensions presents several technical difficulties. Nanoscaling in MOS devices is specifically governed by difficulties in the formation of ultrashallow junctions for the source/drain regions with the requirement of low resistance and low leakage currents. The use of a silicide (forming Schottky contacts at the source and drain) instead of the conventional ion implanted Si for the contacts allows a reduction in the contact area to be made, due to lower serial resistance per unit area of the silicide. According to the specific contact resistance dependence on the Schottky barrier height (ΦSB) and active dopant concentration (ND),

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26

Theodore, N. David, Vida Ilderem, and Ming Pan. "Oxide-induced deterioration of TiSi2 source/drain MOSFET contacts." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 862–63. http://dx.doi.org/10.1017/s0424820100172048.

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A simple process for formation of a metal-oxide-semiconductor field-effect transistor (MOSFET) involves fabrication of a polysilicon/oxide gate between source and drain regions. Contact is made to source/drain regions by use of TiSi2 layers followed by Al(Cu) metal lines. A silicide layeris used toreduce contact resistance. TiSi2 is chosen as a contact layer because in the C54phase, the silicide has a lower resistivity (~12 μΏ-cm) than most other silicides (except for CoSi2 ~10-15 μΏ-cm). During formation of TiSi2 contact layers to MOSFET source/drain regions, a deterioration of the TiSi2 is occasionally observed. The deterioration typically consists of buckling and delamination of Ti(TiSi2) films from the source/drain regions. When buckling occurs, electrical contact between Al metal and MOSFET source/drain regions is quite poor. The present study investigates the microstructure and behavior of TiSi2 contact layers used at source/drain regions of MOSFETs. The cause of deterioration of contact-layers is investigated and a potential solution to this problem is explored.

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27

Kuroki, Shinichiro, Hirofumi Nagatsuma, Milantha de Silva, Seiji Ishikawa, Tomonori Maeda, Hiroshi Sezaki, Takamaro Kikkawa, et al. "Characterization of 4H-SiC nMOSFETs in Harsh Environments, High-Temperature and High Gamma-Ray Radiation." Materials Science Forum 858 (May 2016): 864–67. http://dx.doi.org/10.4028/www.scientific.net/msf.858.864.

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Characteristics of 4H-SiC nMOSFETs with arsenic-doped S/D and NbNi silicide contacts in harsh environments of high-temperature up to 450°C, and high gamma-ray radiation up to over 100 Mrad, were investigated. At high temperature, field effect mobility increased as proportional to T3/2, and threshold voltage was shifted with temperature coefficients of -4.3 mV/K and -2.6 mV/K for oxide thicknesses of 10 nm and 20 nm, respectively. After Co60 gamma-ray exposure of 113 Mrad, the field effect mobility was varied within 8% for oxide thickness of 10 nm, however for 20 nm oxide thickness, this variation was 26%. The threshold voltage shifts were within 6%.

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28

Fomenko, S. M., E. E. Dilmukhambetov, Z. A. Mansurov, Zh Korkembai, and A. N. Alipbaev. "SHS - Processes in the Carbonaceous Oxide System at High Nitrogen Pressure Values." Eurasian Chemico-Technological Journal 15, no. 1 (December 24, 2012): 31. http://dx.doi.org/10.18321/ectj137.

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<p>This paper contains study results of the nitride containing composites features formed in the compacted Al-TiO<sub>2</sub>-C-Si samples inside a high pressure reactor with various nitrogen pressure values. The nitriding and carbide-formation processes take place simultaneously with aluminothermic reduction of titanium oxide in the self-propagating high-temperature synthesis (SHS) mode. It has been found that the nitrogen pressure effect is manifested as insignificant reduction of the combustion temperature and increased durability of the synthesized composite. The SHS process in the nitric environment leads to practically complete reduction of titanium oxide, the free titanium being absent. The X-ray analysis has revealed that the basic SHS products are refractory compounds such as metal nitrides, carbides, and oxides. Increase in nitrogen pressure results in decrease of the specific electric resistance of the synthesized composites caused by growth of the electroconductive phases i.e. titanium carbides, nitrides, and silicides. Performed electron microscopic study including the energy dispersion analysis of the morphology and structure of the SHS products has revealed formation of the nano-sized titanium silicide crystals distributed between the complex carbonitride particles. The complex carbonitride composites synthesized in the high pressure reactor are of interest as highrefractory and abrasive materials considering their physical and chemical properties.</p>

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29

Maung, Si Thu Myint, Tawat Chanadee, and Sutham Niyomwas. "Synthesis of WSi₂-W₅Si₃ Intermetallic Alloy via Self-Propagating High Temperature Synthesis." Solid State Phenomena 280 (August 2018): 121–26. http://dx.doi.org/10.4028/www.scientific.net/ssp.280.121.

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Intermetallic alloy of tungsten silicide (WSi2-W5Si3) was synthesized by self-propagating high temperature synthesis (SHS) from the reactant of tungsten oxide (WO3) and silicon lump (Si) using magnesium (Mg) as fuel. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the possible reacting species. The as-SHS products were characterized by X-ray diffraction (XRD) technique. The magnesiothermic reaction process successfully synthesized dense of WSi2-W5Si3intermetallic alloy. According to the experimental results, it can be proposed that the reaction also promotes the phase separation between alloy and oxide slag of the product.

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30

Yang, Wonchul, Choong-Heui Chung, Sangyeob Lee, Kyeong Ho Baek, Youngmoo Kim, Seong Lee, and Joon Sik Park. "Microstructures and Oxidation Behaviors of Silicide Coated Nb Alloys by Halide Activated Pack Cementation Process." Korean Journal of Metals and Materials 58, no. 8 (August 5, 2020): 507–14. http://dx.doi.org/10.3365/kjmm.2020.58.8.507.

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In this study, we tried to improve the oxidation resistance of Nb-12Si (wt%) alloys at 1200 °C or higher through pack cementation coatings. Nb-12Si (wt%) alloys were prepared by arc-melting under Ar atmosphere. When the alloys were coated using pack powder mixtures composed of Si, Al2O3 and NaF, two silicide layers composed of NbSi2 and Nb5Si3 phases were successfully produced on the substrate. The Si-pack coatings were performed with various heat treatment temperatures and time conditions. The microstructures and thickness changes of the coating layers were analyzed to determine the growth behaviors of the coating layer. The growth constant of 8.4 10–9 cm2/sec was obtained with a diffusion growth mode. In addition, in order to examine the resistance of the Si-pack coated alloys, isothermal static oxidation tests were performed at 1200 °C and higher temperatures. As a result, the oxidation resistance of the alloys was determined by protecting the surface of the alloys with silicide oxide layers formed by the silicide coatings. The uncoated specimens exhibited an abnormal weight increase due to the formation of Nb oxide. The coated specimen showed excellent oxidation resistance at 1200 °C for up to 12 hrs, while the previous reports on the same alloy verified oxidation resistance only up to 1100 °C. It appears that the excellent oxidation resistance is closely related to the NbSi2 coating layer thickness. The oxidation behaviors of the coating layers after the oxidation tests were discussed in terms of microstructural and phase analyses.

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31

Ichinohe, T., S. Masaki, K. Kawasaki, and H. Morisaki. "Palladium silicide/oxide formations in Pd/SiO2 complex films." Thin Solid Films 343-344 (April 1999): 119–22. http://dx.doi.org/10.1016/s0040-6090(98)01626-5.

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32

Huang, Jen-Yun, and Shinn-Tyan Wu. "Influence of Interfacial Oxide on Self-Alignment Silicide Process." Japanese Journal of Applied Physics 37, Part 1, No. 11 (November 15, 1998): 6085–89. http://dx.doi.org/10.1143/jjap.37.6085.

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33

Montero, I., A. Climent-Font, J. Perrière, D. Levy, and J. M. Martinez-Duart. "Formation kinetics and composition of titanium silicide anodic oxide." Electrochimica Acta 38, no. 2-3 (February 1993): 399–403. http://dx.doi.org/10.1016/0013-4686(93)85157-t.

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34

Yakaboylu, Gunes, Rajalekshmi Pillai, Katarzyna Sabolsky, and Edward Sabolsky. "Fabrication and Thermoelectric Characterization of Transition Metal Silicide-Based Composite Thermocouples." Sensors 18, no. 11 (November 3, 2018): 3759. http://dx.doi.org/10.3390/s18113759.

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Metal silicide-based thermocouples were fabricated by screen printing thick films of the powder compositions onto alumina tapes followed by lamination and sintering processes. The legs of the embedded thermocouples were composed of composite compositions consisting of MoSi2, WSi2, ZrSi2, or TaSi2 with an additional 10 vol % Al2O3 to form a silicide–oxide composite. The structural and high-temperature thermoelectric properties of the composite thermocouples were examined using X-ray diffraction, scanning electron microscopy and a typical hot–cold junction measurement technique. MoSi2-Al2O3 and WSi2-Al2O3 composites exhibited higher intrinsic Seebeck coefficients (22.2–30.0 µV/K) at high-temperature gradients, which were calculated from the thermoelectric data of composite//Pt thermocouples. The composite thermocouples generated a thermoelectric voltage up to 16.0 mV at high-temperature gradients. The MoSi2-Al2O3//TaSi2-Al2O3 thermocouple displayed a better performance at high temperatures. The Seebeck coefficients of composite thermocouples were found to range between 20.9 and 73.0 µV/K at a temperature gradient of 1000 °C. There was a significant difference between the calculated and measured Seebeck coefficients of these thermocouples, which indicated the significant influence of secondary silicide phases (e.g., Mo5Si3, Ta5Si3) and possible local compositional changes on the overall thermoelectric response. The thermoelectric performance, high sensitivity, and cost efficiency of metal silicide–alumina ceramic composite thermocouples showed promise for high-temperature and harsh-environment sensing applications.

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35

Gosink, Hans-Jürgen, Herbert W. Roesky, Mathias Noltemeyer, Hans-Georg Schmidt, Cristina Freire-Erdbrügger, and George M. Sheldrick. "Modellreaktionen zur Verankerung von Molybdän-und Vanadium-Oxiden auf Silicium-Sauerstoff-Oberflächen." Chemische Berichte 126, no. 2 (February 1993): 279–83. http://dx.doi.org/10.1002/cber.19931260202.

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36

Rokosik, E., K. Dwiecki, M. Rudzińska, A. Siger, and K. Polewski. "Column chromatography as a method for minor components removal from rapeseed oil." Grasas y Aceites 70, no. 3 (May 7, 2019): 316. http://dx.doi.org/10.3989/gya.0709182.

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The purpose of this study was to verify the influence of different chromatographic column beds (silicic acid, activated charcoal, aluminum oxide, silica gel) on the concentration of individual minor components (sterols, tocopherols, carotenoids and chlorophyll) in rapeseed oil. With the use of a combination of these beds, a three-stage optimized method for removing minor components from rapeseed oil was developed. It was demonstrated that the combination of silicic acid and activated charcoal removed about half of the sterols present from the oil. Aluminum oxide turned out to be the most effective bed in removing tocopherols, purifying the oil to their minimum level (2.6 mg/kg). All adsorbents used had similar capacity to purify oil from pigments (carotenoids and chlorophyll). In the three-stage purification process free sterols were almost completely removed (to the level 90.0 mg/kg). Purification of β-carotene and chlorophyll from the oil was also very effective. Tocopherols were completely removed with this method, except for a small amount of α-tocopherol (0.4 mg/kg), which results from its relatively weak interaction with a hydrophilic bed. The developed method may be used in studies on the effect of association colloids on bulk oil autoxidation processes.

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37

Wong-Ng, Winnie, Howard F. McMurdie, Boris Paretzkin, Yuming Zhang, Katherine L. Davis, Camden R. Hubbard, Alan L. Dragoo, and James M. Stewart. "Standard X-Ray Diffraction Powder Patterns of Sixteen Ceramic Phases." Powder Diffraction 2, no. 3 (September 1987): 191–202. http://dx.doi.org/10.1017/s0885715600012690.

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The following sixteen reference patterns of boride, silicide, nitride and oxide ceramics represent the second group of reference patterns measured at the National Bureau of Standards under the project “High Quality Reference Patterns and Total Digital Powder Patterns of Technologically Important Ceramic Phases”. Included in the sixteen reference patterns are data for two high Tc superconducting oxide phases (CuSr0.2La1.8O4 and Ba2Cu3YO7) plus one related phase (BaCuY2O5). In addition to these new phases, five other patterns represent phases previously not contained in the PDF and eight represent major corrections to data in the file. The general methods of producing these X-ray powder diffraction reference patterns are described in this journal, Vol. 1, No. 1, pg. 40 (1986).

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38

Omura, Yasuhisa, Hiroshi Inokawa, and Katsutoshi Izumi. "Titanium silicide and titanium nitride formation by titanium-ion implantation for MOS LSI applications." Journal of Materials Research 6, no. 6 (June 1991): 1238–47. http://dx.doi.org/10.1557/jmr.1991.1238.

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A 70-nm-thick, 19-μΩ · cm TiSi2 layer is formed using a Ti-ion implantation technique. TiN/TiSi2 double layers, whose surface morphology is superior to that obtained with conventional deposition and reaction techniques, can also be simultaneously formed by Ti-ion implantation into monocrystalline Si screened with the Si3N4 film. Discrete pn-junction diodes with a shallow TiSi2 layer and Ti-polycide-gate MOS capacitors are fabricated to determine the influences of Ti-ion implantation on electrical characteristics. The leakage current of the B-doped p+n junction and As/P-doped n+p junction with Ti-ion implanted silicide layer is low enough for device applications. Silicide formation on the gate polycrystalline-Si does not affect the breakdown electric field strength of a 20-nm-thick gate oxide. MOS capacitors showed normal C-V characteristics.

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39

Cao, Yang, Gang Zhou, and Jun Hui He. "Synthesis of Nickel Silicide/Silicon/Silica Composite Nanostructures by Coevaporation of SiO Powder and Nickel Formate." Advanced Materials Research 181-182 (January 2011): 599–603. http://dx.doi.org/10.4028/www.scientific.net/amr.181-182.599.

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Nickel silicide/silicon/silica composite nanostructure, i.e., Ni31Si12/Si/SiO2, was synthesized successfully by a coevaporation method, using nickel formate and SiO powder as the source materials. The structure of product was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscope (HRTEM). The results indicated that the product had a rod morphology, which consisted of three parts with different morphologies and crystallographic structures. The top of the rod was a polycrystalline nickel silicide (Ni31Si12) nanoball with average diameter of 100 nm; the middle part was a single-crystal Si short rod with average diameter of 80 nm; the bottom part was an amorphous silicon oxide nanowire with average diameter of 60 nm. A possible growth mechanism of the composite nanorod was briefly discussed

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40

Andrews-Speed, C. P. "The role of silica and iron oxide mobility in the formation of gold-bearing fluvial sediments in the Proterozoic Mporokoso Basin, northern Zambia." Geological Magazine 123, no. 2 (March 1986): 143–52. http://dx.doi.org/10.1017/s0016756800029794.

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AbstractGold-bearing sandstone and conglomerate near the base of the Proterozoic Mporokoso Group were deposited in a braided river system. The detrital sand grade material is mainly of quartz, sericite and haematite, and the pebbles are of vein-quartz, chert, silicic volcanics, quartzose metasediment and jaspilite. The basement rocks presently exposed in the basement are silicic igneous rocks and quartzose metasediments.The petrography of the fluvial sediments suggests that silica and, to a lesser extent, iron oxide were mobile both in the source-area and in the braided river system. Evidence for silica-mobility includes jaspilite pebbles with spherulites and glaebules of chalcedony, abundant vein-quartz pebbles, intra-basinal sandstone pebbles, and the silicification of volcanic pebbles. The detrital haematite in the fluvial sandstone forms pseudomorphs after magmatic magnetite. Authigenic iron oxide occurs in several forms which suggest that iron oxide was mobile in the source-area and in the fluvial sediments. Uranium is locally abundant in basement and sedimentary rocks, cassiterite is a common heavy mineral in the fluvial sediments, and fluorite has been found in the basement.These features may be explained by intense weathering which mobilized both silica and iron. The silica was concentrated near the surface to form silcretes in the basement and later in the overlying fluvial sediments. Hydrothermal convection cells driven by the granites may have carried silica, iron, tin, fluorine and uranium towards the surface before and during the erosion of the igneous basement.

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41

Rohanda, A., A. Waris, R. Kurniadi, and S. Bakhri. "Gamma Heating Evaluation of Silicide RSG-GAS Multipurpose Reactor." Journal of Physics: Conference Series 2328, no. 1 (August 1, 2022): 012004. http://dx.doi.org/10.1088/1742-6596/2328/1/012004.

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Abstract In research reactor, gamma heating deposited in the samples is an important issue because it is related to the samples and the reactor operational safety. Multi Purpose Reactor (MPR) 30 MWth or its called Reaktor Serba Guna G.A. Siwabessy (RSG-GAS) is a research reactor that play a role as a place to irradiate various target material type. RSG-GAS has been operating since 1987 and the last measurement of gamma heating in the core was conducted around twenty years ago in oxide core. In 1996, RSG-GAS core was converted from oxide fuel type to silicide fuel type. The purpose of the conversion are to improve the performance and efficiency of RSG-GAS. As part of RSG-GAS irradiation facilities safety analysis, the gamma heating measurement was re-conducted in order to obtain latest data as benchmark data in silicide core. This paper presents the results of gamma heating measurement of LEU silicide RSG-GAS core in Central Irradiation Position (CIP) at 15 MW and 30 MW power level using gamma calorimeter. There were four types of calorimeter used, which were calorimeter with graphite (C) sample, iron (Fe) sample, aluminum (Al) sample and zirconium (Zr) sample. Gamma heating calculations using GAMSET code were performed to verify the measurement results. The measurement results are lower than the GAMSET results and the gamma heating value increases in proportion to the increase of calorimeter sample atomic number. This results are corresponds to gamma heating benchmarking results of RSG-GAS oxide core. Several optimization efforts both measuring and modeling with GAMSET were conducted as an evaluation and justification of the results. The best optimization results are achieved using the maximum value of the measurement and adjusting the power peaking factor (PPF) distribution. The calculated gamma heating value optimization results at 15 MW power are 2.78 W/g (C sample), 2.74 W/g (Al sample), 3.36 W/g (Fe sample) and 4.60 W/g (Zr sample) while at 30 MW power level are 5.57 W/g (C sample), 5.49 W/g (Al sample), 6.75 W/g (Fe sample) and 9.23 W/g (Zr sample). The best optimization results serve as a benchmark data for developing new gamma heating calculation programs based on 18 gamma energy groups.

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42

Lam, Lawrence K., and Dieter G. Ast. "Characterization of Thin Films on Oxide Using a Unique Tem Specimen Preparation Process." Microscopy and Microanalysis 5, S2 (August 1999): 934–35. http://dx.doi.org/10.1017/s1431927600017992.

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Transmission Electron Microscopy technique is a powerful tool to examine microstructures. However, the specimen preparation process usually requires tedious and careful cutting and lapping. In this paper, we present a TEM specimen preparation process which is simple, requires about one hour, and allows specific areas of patterned films deposited on silicon dioxide to be examined. The sample consisted of three thin film layers deposited on a Corning 1737 glass substrate. The top layer was 1000 A thick, low temperature oxide; the middle layer, 1000 A thick; amorphous silicon; the bottom layer, 1000 A thick, low temperature oxide. The top oxide layer was patterned to contain a square array of 10 × l0um openings, with a 100 um center to center spacing. A thin nickel layer was the evaporated, and the specimen was heated to form nickel silicide in the 10 × 10 um areas where Ni and Si were in contact.

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43

Mitra, Rahul. "Oxidation Behavior of Silicides." Diffusion Foundations 21 (March 2019): 127–56. http://dx.doi.org/10.4028/www.scientific.net/df.21.127.

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The oxidation behavior of Mo, Nb, and Ti-silicides has received significant attention in past few decades for their potential to be used as high temperature structural materials. These Si-bearing intermetallic alloys have the ability to form an oxide scale containing SiO2, which is protective if formed as a continuous and impervious layer, so that the ingress of oxygen from atmosphere to the underneath alloy is restricted. To form a continuous and stable SiO2scale, it is important to have sufficient activity of Si along with thermodynamic and kinetic conditions favoring its growth in comparison to that of oxides of other alloying elements. MoSi2has superior oxidation resistance compared to that of Mo3Si or Mo5Si3, because of its higher Si content. Furthermore, a continuous film of SiO2is able to form at temperatures in the range of 800-1700oC on MoSi2due to vaporization of MoO3, but not on NbSi2or TiSi2due to competitive growth of Nb2O5or TiO2, respectively. During past two decades, a significant effort has been devoted to development of Mo-Si-B alloys containing Mo-rich solid solution, Mo3Si and Mo5SiB2as constituent phases, due to their ability to form a protective borosilicate scale. The presence of B2O3contributes to fluidity of borosilicate scale, thereby contributing to closure of porosities. Efforts have been also made to develop multicomponent Nb-silicide based alloys with optimum combination of mechanical properties and high temperature oxidation resistance with limited success. There have been efforts to develop silicide based coatings for protection oxidation for Mo-rich Mo-Si-B alloys and Nb-Si based ternary or multicomponent alloys with inadequate oxidation resistance. Oxidation behavior of selected silicides with potential for structural application, along with mechanisms for protection against oxidation has been reviewed and discussed.

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44

Girardeaux, Christophe, Brice Sarpi, and Sébastien Vizzini. "Study of the Very First Stages of Mg Growth onto Si(100)." Defect and Diffusion Forum 383 (February 2018): 83–88. http://dx.doi.org/10.4028/www.scientific.net/ddf.383.83.

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Generation of ultra-thin oxide layers (in the nanometer range) is currently a technological lock for numerous applications such as microelectronics, spintronics or even molecular electronics. A precise study of the stages of growth of Mg is essential before studying the growth of the oxide. In this work we report and discuss an experimental study of the very first stages of Mg growth onto Si(100) by Scanning Tunneling Microscopy-Spectroscopy (STM-STS), Auger Electron Spectroscopy (AES) and Low Energy Electron Diffraction (LEED). First, we have shown that an amorphous underlayer is formed onto the silicon substrate for Mg deposits of 0.25 monolayers (ML). This underlayer is attributed to a Mg2Si silicide formed at RT during Mg deposition. Then, using an original growth method based on alternate cycles of magnesium monolayer adsorption and room temperature (RT) oxidation, we did grow ultra-thin magnesium oxide films onto Si(100). Our study revealed that the ultra-thin Mg2Si layer at the MgO/Si(100) interface acts as a diffusion barrier and prevents oxidation of the highly-reactive silicon during magnesium oxide growth.

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45

Omar, Nurul Amanina Binti, Frank Hahn, Frank Koester, and Andreas Bund. "Electroless Deposition of Nickel-Phosphorus Composite Layer with Incorporated Amorph Boron Particles and Subsequent Heat Treatment for the Formation of Nickelboride." ECS Meeting Abstracts MA2022-01, no. 22 (July 7, 2022): 1111. http://dx.doi.org/10.1149/ma2022-01221111mtgabs.

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In an effort to decrease the operating cost in the manufacturing industries, industrial knives and large tools in the forming technology should possess characteristics that increase its lifetime. One such properties would be the high surface hardness and a possibility to improve this characteristic would be through boriding. Through this method, whereby boron powder or paste is spread on the tool surface before the workpiece is heated in the oven at 750 – 950 °C for 4 – 6 h, a diffusion process occurs between the boron paste and the substrate. Borides are formed in the workpiece until a depth of approx. 250 µm from the workpiece surface depending on the substrate type and the heat treatment parameters. Genel et al. attained a hardness value of around 1700 HV at 75 µm depth when they borided AISI W1 steel workpiece at 950 °C for 6h[1],[2],[3]. By boriding a nickel superalloy, Inconel 718, at 950°C for 6h, Campos-Silva et al. achieved approx. 2200 HV at 30 µm depth[4]. However this method is disadvantageous in terms of the high energy cost and the long treatment period. As an alternative, hard chrome layer that has a hardness value between 600 to 1200 HV[5],[6] can be electroplated on the workpiece. Besides having an improved wear protection, this chrome layer offers a good corrosion protection and can be produced with a lower cost since it does not need a thermal post-treatment to increase its hardness and hence this method is less energy intensive as boriding. Admittedly the application of chrome-VI ions in the hard chrome electrolyte is without special permission prohibited in the European Union since 2017 according to REACH[7] considering its carcinogenic properties[8],[9],[10]. Another possible method would be through composite coating. Many works have been done on electroless composite nickel coating with boron nitride, silicium carbide, diamonds, aluminium oxide and titanium oxide among others used as dispersoid. After a heat treatment at 400 °C for 1 h, the hardness of most of these coating increases significantly from around 700 HV to approx. 1100 HV[11]. In the present study, the positive aspects of boriding and electroless deposition of nickel-phosphorus layer should be combined, so that a hard surface with a good wear resistant can be produced for industrial tools in a more efficient way. It is expected that lower heat treatment temperature and/or less treatment time is needed to achieve the same effect as boriding since boron particles are already homogenously distributed and have a shorter diffusion path in the thick composite layer. In addition to that, the hardness gradient throughout the heat-treated composite nickel coating should be much lower compared to boriding, especially when a high amount of boron particles is evenly distributed in the layer. The coating thickness, which will then be equated as boride layer thickness after sufficient heat treatment, can be manipulated with coating parameters and electrolyte type. Hence, through this combined method, a thicker boride layer is achievable by depositing a thicker composite nickel layer. Amorph boron powder of different sizes are used as dispersoid in the composite electroless nickel layer. The dependency of incorporated boron content in the composite layer with the particle content in the electrolyte, the particle size and the effect of ultrasound-assisted deposition is investigated. A homogenous particle distribution in the deposited layer and controllable incorporation of the boron particle in the nickel-phosphorus matrix are desirable. Furthermore, the agglomeration behaviour of the boron particle in the electrolyte is examined through laser doppler electrophoresis. The influence of the incorporated boron particle on the coating hardness and its wear resistance before and after heat treatment is studied by measuring it according to Vickers and with Calotester kaloMAX NT II. The effect of the heat treatment parameters with respect to the heat-treating temperature and time to the surface hardness and its wear resistance is investigated. At the conference results of the metallographic examinations, SEM-EDS and XRD analysis will be presented. Figure 1

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46

Wong-Ng, Winnie, Howard F. McMurdie, Boris Paretzkin, Camden R. Hubbard, Alan L. Dragoo, and James M. Stewart. "Standard X-Ray Diffraction Powder Patterns of Fifteen Ceramic Phases." Powder Diffraction 2, no. 2 (June 1987): 106–17. http://dx.doi.org/10.1017/s0885715600012495.

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The following fifteen reference patterns of boride, silicide and oxide ceramics represent the first group of ceramic phases measured at the National Bureau of Standards under the project “High Quality Reference Patterns and Total Digital Powder Patterns of Technologically Important Ceramic Phases”. The support and interest of the JCPDS-ICDD in this project is gratefully acknowledged.The general methods of producing these X-ray powder diffraction reference patterns are described in this journal, Vol. 1, No. 1, pg. 40(1986).

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47

Reckeweg, Olaf, and Francis J. DiSalvo. "Oxide meets silicide – synthesis and single-crystal structure of Ca21SrSi24O2." Zeitschrift für Naturforschung B 72, no. 4 (April 1, 2017): 313–16. http://dx.doi.org/10.1515/znb-2017-0022.

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AbstractA few black, rectangular thin plates of Ca21SrSi24O2 were obtained by serendipity in a solid-state reaction of calcium metal, strontium chloride and silicon powder at 1200 K for 2 days designed to produce ‘Ca2SrCl2[Si3]’. The title compound forms next to some CaSi and some remaining educts. Ca21SrSi24O2 crystallizes in the monoclinic space group C2/m (no. 12) with unit cell parameters of a=1895.2(2), b=450.63(5) and c=1397.33(18) pm and β=112.008(7)° (Z=1). The title compound shows planar, eight-membered, kinked Si8 chains with Si–Si distances between 241.4 and 245.0 pm indicating bonding interactions and kinked ‘rope ladders’ connecting the chains with interatomic Si–Si distances in the range 268.1–274.7 pm. Embedded in between these silicon substructures are columns of oxygen centered, apex sharing [(Ca1−x Srx)6/2O] octahedra and calcium ions.

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48

WHITE, A. E., and K. T. SHORT. "Synthesis of Buried Oxide and Silicide Layers with Ion Beams." Science 241, no. 4868 (August 19, 1988): 930–35. http://dx.doi.org/10.1126/science.241.4868.930.

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49

Hernández-Negrete, Ofelia, and Panos Tsakiropoulos. "On the Microstructure and Isothermal Oxidation of the Si-22Fe-12Cr-12Al-10Ti-5Nb (at.%) Alloy." Materials 12, no. 11 (June 3, 2019): 1806. http://dx.doi.org/10.3390/ma12111806.

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Nb-silicide based alloys are new ultra-high temperature materials that could replace Ni-based superalloys. Environmentally resistant coating system (s) with αAl2O3 or SiO2 forming bond coat alloys that are chemically compatible with the Nb-silicide based alloy substrates are needed. This paper makes a contribution to the search for non-pesting bond coat alloys. The microstructure and isothermal oxidation at 800 °C of the silicide-based alloy Si-22Fe-12Cr-12Al-10Ti-5Nb (OHC2) were studied. The cast alloy exhibited macrosegregation of all elements. The microstructures in the cast alloy and after the heat treatment at 800 °C consisted of the same phases, namely TM6Si5, TM5Si3 (TM = transition metal), FeSi2Ti, Fe3Al2Si3, (Fe,Cr)(Si,Al), and an unknown phase of dark contrast. The latter two phases were not stable at 950 °C, where the TMSi2 was formed. There was evidence of endothermic reaction(s) below 1200 °C and liquation at 1200 °C. The alloy followed parabolic oxidation kinetics after the first hour of isothermal oxidation at 800 °C, did not pest, and formed a self-healing scale, in which the dominant oxide was Al2O3. The alloy was compared with other alumina or silica scale-forming intermetallic alloys and approaches to the design of bond coat alloys were suggested.

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50

Nobili, C., F. Nava, G. Ottaviani, M. Costato, G. De Santi, and G. Queirolo. "Titanium Silicide Formation in Presence of Oxygen." Active and Passive Electronic Components 15, no. 1 (1992): 9–26. http://dx.doi.org/10.1155/1992/94394.

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In-situ resistivity vs. temperature, Rutherford backscattering spectrometry, Auger electron spectroscopy and X-ray diffraction measurements have been performed in order to study the effects arising from the presence of oxygen in the annealing ambient on the integrity of amorphous films of TiSix, with x ranging from 1.45 to 2.1. Crystalisation occurs around 400 C. The presence of oxygen produces the formation of silicon and titanium oxide around 500 C. Critical analysis of the experimental results have indicated that metal oxidation is inhibited when an excess of silicon is present, which suggests the use of a sputtered Si coating cap as a medium capable of effectively decoupling the silicide film from oxygen. This avoids unwanted Ti oxidation even in heavily oxygen contaminated ambients up to the highest temperatures used for the formation of low resistivity titanium disilicide.

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