Journal articles: 'Dioxyde de silicium'

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Oliviero, F., P. Frallonardo, L. Peruzzo, A. Scanu, R. Ramonda, P. Sfriso, L. Tauro, F. Lioté, and L. Punzi. "Identification des cristaux de dioxyde de silicium dans le liquide synovial arthrosique." Revue du Rhumatisme 74, no. 10-11 (November 2007): 1086. http://dx.doi.org/10.1016/j.rhum.2007.10.123.

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Realdon, Nicola, Enrico Ragazzi, Marisa Dal Zotto, and Gabriella Dalla Fini. "Effects of Silicium Dioxide on Drug Release from Suppositories." Drug Development and Industrial Pharmacy 23, no. 11 (January 1997): 1025–41. http://dx.doi.org/10.3109/03639049709150491.

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Leboda, R., V. A. Tertykh, V. V. Sidorchuk, and J. Skubiszewska-Ziȩba. "Peculiarities of steam-phase hydrothermal modification of pyrogenic silicium dioxide." Colloids and Surfaces A: Physicochemical and Engineering Aspects 135, no. 1-3 (April 1998): 253–65. http://dx.doi.org/10.1016/s0927-7757(97)00258-6.

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Pyell, Ute. "CE characterization of semiconductor nanocrystals encapsulated with amorphous silicium dioxide." ELECTROPHORESIS 29, no. 3 (February 2008): 576–89. http://dx.doi.org/10.1002/elps.200700411.

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Dördelmann, Gregor, Hendrik Pfeiffer, Alexander Birkner, and Ulrich Schatzschneider. "Silicium Dioxide Nanoparticles As Carriers for Photoactivatable CO-Releasing Molecules (PhotoCORMs)." Inorganic Chemistry 50, no. 10 (May 16, 2011): 4362–67. http://dx.doi.org/10.1021/ic1024197.

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Hoffmann, C., P. Plate, A. Steinbrück, and S. Kaskel. "Nanoporous silicon carbide as nickel support for the carbon dioxide reforming of methane." Catalysis Science & Technology 5, no. 8 (2015): 4174–83. http://dx.doi.org/10.1039/c4cy01234h.

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High surface area SiCs are used as supports for nickel in the carbon dioxide reforming of methane. Proper pre-treatment of the SiC suppressed nickel silicide formation and allowed high levels of activity.

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Panteleeva, Viktoriya V., and Anatoliy B. Shein. "ANODIC PROCESSES ON NiSi ELECTRODE IN SODIUM HYDROXIDE SOLUTIONS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, no. 2 (July 11, 2018): 64. http://dx.doi.org/10.6060/tcct.20165902.5269.

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Anodic behavior of NiSi in (0.1 – 5.0) M NaOH in the range of potentials from corrosion potential up to oxygen evolution potential was studied using methods of polarization and impedance measurements. It was concluded that in the alkaline electrolyte the selective dissolution of silicon from the nickel silicide occurs. High chemical resistance of NiSi is due to the formation on its surface the passivating film, consisting mainly from poorly soluble products of anodic oxidation of nickel (it may also include a small content of silicon dioxide and silicates). The equivalent electrical circuit modeling the passive state of the silicide was proposed.

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Nemuschenko, Dmitry A., Vladimir V. Larichkin, Anastasiya P. Onipchenko, and Vasilij S. Subbotin. "A research into the distribution of silicium dioxide nanoparticles in the mixing water." Vestnik MGSU, no. 5 (May 2020): 678–87. http://dx.doi.org/10.22227/1997-0935.2020.5.678-687.

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Introduction. The co-authors studied suspensions of silicium dioxide nanoparticles in the water. The application of suspensions helps to most effectively add nanoparticles to slip ceramic mixtures and mixtures that contain concrete. A review of publications has proven that Russian and foreign researchers are willing to learn more about nanoparticles used to modify various materials. Particles having different chemical properties are applied depending on the types of problems to be solved. The method of ultrasonic dispersion of fillers in the matrix material is widely used; surfactants stabilize suspensions and mortars. Silicon dioxide, being one of the cheapest ultra-dispersed powders, has been proven as an active filler designated for building materials. Materials and methods. A method of ultrasonic dispersion was used to uniformly distribute nanoparticles in the water. A surfactant was added to the suspension to reduce the reaggregation of particles and to rise the stability of suspensions in the course of time. The turbidimetric method was employed to control the nanoparticle distribution efficiency in the suspension, and a spectrophotometer was used to identify the dimensions of solid particles by measuring the optical density. Results. The co-authors have proven the efficiency of the ultrasonic method in distributing nano-sized particles over the water. The suspensions, developed by the co-authors, were used to mold samples of ceramics; a scanning electron microscope and a nozzle, designated for the identification of chemical compositions, were used to identify dimensions of nanoparticle conglomerates in the matrix. The co-authors identified the concentration of OP-10 surfactant that was optimal for the destruction of conglomerates in the suspension; the impact of the ultrasonic treatment duration was assessed in respect of the suspension. Conclusions. The research findings can be contributed to ceramic production technologies for versatile nanoparticles to be employed to modify materials.

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Devyatkin, S. V. "Electrochemistry of silicon in chloro-fluoride and carbonate melts." Journal of Mining and Metallurgy, Section B: Metallurgy 39, no. 1-2 (2003): 303–7. http://dx.doi.org/10.2298/jmmb0302303d.

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The electrochemical behavior of K2SiF6 in chloro-fluoride melts and that of SiO2 in carbonate melts has been studied. Silicon, titanium silicides, boron silicide and ternary compounds Ti-Si-B have been deposited from chloro-fluoride melts. Only SiC was deposited from carbonate-silica melts under carbon dioxide atmosphere (that is, excessive pressure of CO2).

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d’Heurle, F. M., R. D. Frampton, E. A. Irene, Hao Jiang, and C. S. Petersson. "Rate of formation of silicon dioxide; semiconducting ruthenium silicide." Applied Physics Letters 47, no. 11 (December 1985): 1170–72. http://dx.doi.org/10.1063/1.96315.

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Минаков, А. В., А. С. Лобасов, М. И. Пряжников, Л. С. Тарасова, Н. Я. Василенко, and В. Я. Рудяк. "Экспериментальное исследование влияния наночастиц на процессы испарения жидкостей." Журнал технической физики 90, no. 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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Matsushita, Jun-Ichi, Tatsuki Satsukawa, Naoya Iwamoto, Xiao Ling Wang, Jian Feng Yang, Tomoyo Goto, Tohru Sekino, Xiao Yong Wu, Shu Yin, and Tsugio Sato. "Oxidation of Pentatitanium Trisilicide (Ti₅Si₃) Powder at High Temperature." Materials Science Forum 868 (August 2016): 38–42. http://dx.doi.org/10.4028/www.scientific.net/msf.868.38.

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The oxidation of pentatitanium trisilicide (Ti5Si3) powder at high temperature was investigated in order to determine the suitability of this ceramic material for advanced application in an oxidation atmosphere at high temperature. Titanium silicide has been attracted for years as an engineering ceramics due to its high hardness, high melting point, and good chemical stability. The samples were oxidized from 300 to 1000 °C for 1 to 5 h in air. The mass changes were measured to estimate the oxidation resistance of the sample. The mass gain of the sample oxidized at 1000 °C for 5 h was about 26 % of the theoretical oxidation mass change. The commercial powder, Ti5Si3 showed an excellent oxidation resistance at 1000 °C, because the surface film of both titanium dioxide and silicon dioxide formed by oxidation acted as an oxidation resistant layer.

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Al-Hakeim, Hussein Kadhem, Khlowd Mohammed Jasem, and Shatha Rouf Moustafa. "Anti-pepsin activity of silicon dioxide nanoparticles." Revista Colombiana de Química 45, no. 3 (September 1, 2016): 5. http://dx.doi.org/10.15446/rev.colomb.quim.v45n3.58760.

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Se usaron nanopartículas de dióxido de silicio como inhibidores de la pepsina para el tratamiento del reflujo gastroesofágico (GERD). Estas nanopartículas (SiO2NPs recubiertas de pepsina) son unas de las más seguras y pueden usarse en el cuerpo humano. Se midió a través de espectrofotometría la actividad de la pepsina antes y después de añadir cierta cantidad de NPs a la mezcla reactante. Adicionalmente, se repitieron estas pruebas a diferentes temperaturas, variando el peso de las NPs y la fuerza iónica. Se calcularon los parámetros cinéticos (Km y Vmax) de las reacciones catalizadas con pepsina a través de las gráficas de Lineweaver-Burke. Los resultados mostraron que, usando SiO2NPs (Vmax de pepsina libre = 4.82 U y Vmax de pepsina inmovilizada = 2.90 U) y a través de la presencia de fuerza iónica, la actividad enzimática se reduce significativamente. Se concluye que la mejor condición para inhibir la actividad enzimática es usando una combinación de SiO2NPs y una alta concentración de NaCl a 37 °C.

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Perminova, L. V., G. A. Kovalenko, N. A. Rudina, L. I. Sapunova, I. O. Tamkovic, and A. G. Lobanok. "Catalytical properties of Arthrobacter nicotianae cells, a producer of glucose isomerase, immobilized inside xerogel of silicium dioxide." Applied Biochemistry and Microbiology 45, no. 4 (July 2009): 389–94. http://dx.doi.org/10.1134/s0003683809040073.

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15

Sigmarsson, O., I. Vlastelic, R. Andreasen, I. Bindeman, J. L. Devidal, S. Moune, J. K. Keiding, G. Larsen, A. Höskuldsson, and Th Thordarson. "Remobilization of silicic intrusion by mafic magmas during the 2010 Eyjafjallajökull eruption." Solid Earth 2, no. 2 (December 2, 2011): 271–81. http://dx.doi.org/10.5194/se-2-271-2011.

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Abstract. Injection of basaltic magmas into silicic crustal holding chambers and subsequent magma mingling or mixing is a process that has been recognised since the late seventies as resulting in explosive eruptions. Detailed reconstruction and assessment of the mixing process caused by such intrusion is now possible because of the exceptional time-sequence sample suite available from the tephra fallout of the 2010 summit eruption at Eyjafjallajökull volcano in South Iceland. Fallout from 14 to 19 April contains three glass types of basaltic, intermediate, and silicic compositions recording rapid magma mingling without homogenisation, involving evolved FeTi-basalt and silicic melt with composition identical to that produced by the 1821–1823 AD Eyjafjallajökull summit eruption. The time-dependent change in the magma composition suggests a binary mixing process with changing end-member compositions and proportions. Beginning of May, a new injection of primitive basalt was recorded by deep seismicity, appearance of Mg-rich olivine phenocrysts together with high sulphur dioxide output and presence of sulphide crystals. Thus, the composition of the basaltic injection became more magnesian and hotter with time provoking changes in the silicic mixing end-member from pre-existing melt to the solid carapace of the magma chamber. Finally, decreasing proportions of the mafic end-member with time in the erupted mixed-magma demonstrate that injections of Mg-rich basalt was the motor of the 2010 Eyjafjallajökull explosive eruption, and that its decreasing inflow terminated the eruption. Significant quantity of silicic magma is thus still present in the interior of the volcano. Our results show that detailed sampling during the entire eruption was essential for deciphering the complex magmatic processes at play, i.e. the dynamics of the magma mingling and mixing. Finally, the rapid compositional changes in the eruptive products suggest that magma mingling occurs on a timescale of a few hours to days whereas the interval between the first detected magma injection and eruption was several months.

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Dubes, Virginie, Thibaud Parpaite, Thomas Ducret, Jean-François Quignard, Stéphane Mornet, Nora Reinhardt, Isabelle Baudrimont, et al. "Calcium signalling induced by in vitro exposure to silicium dioxide nanoparticles in rat pulmonary artery smooth muscle cells." Toxicology 375 (January 2017): 37–47. http://dx.doi.org/10.1016/j.tox.2016.12.002.

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17

Arkhipov, S. A., V. A. Shkurupy, and Yu S. Bugrimova. "Effect of Preliminary Load of Macrophages with Silicium Dioxide on Phagocytosis of BCG Strain Micobacteria by Macrophages and Antimicrobial Activity." Bulletin of Experimental Biology and Medicine 149, no. 4 (September 22, 2010): 534–36. http://dx.doi.org/10.1007/s10517-010-0986-0.

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Zexer, Nerya, and Rivka Elbaum. "Unique lignin modifications pattern the nucleation of silica in sorghum endodermis." Journal of Experimental Botany 71, no. 21 (March 9, 2020): 6818–29. http://dx.doi.org/10.1093/jxb/eraa127.

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Abstract Silicon dioxide in the form of hydrated silica is a component of plant tissues that can constitute several percent by dry weight in certain taxa. Nonetheless, the mechanism of plant silica formation is mostly unknown. Silicon (Si) is taken up from the soil by roots in the form of monosilicic acid molecules. The silicic acid is carried in the xylem and subsequently polymerizes in target sites to silica. In roots of sorghum (Sorghum bicolor), silica aggregates form in an orderly pattern along the inner tangential cell walls of endodermis cells. Using Raman microspectroscopy, autofluorescence, and scanning electron microscopy, we investigated the structure and composition of developing aggregates in roots of sorghum seedlings. Putative silica aggregation loci were identified in roots grown under Si starvation. These micrometer-scale spots were constructed of tightly packed modified lignin, and nucleated trace concentrations of silicic acid. Substantial variation in cell wall autofluorescence between Si+ and Si– roots demonstrated the impact of Si on cell wall chemistry. We propose that in Si– roots, the modified lignin cross-linked into the cell wall and lost its ability to nucleate silica. In Si+ roots, silica polymerized on the modified lignin and altered its structure. Our work demonstrates a high degree of control over lignin and silica deposition in cell walls.

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Lee, Ming-Kwei, Chung-Min Shih, and Chi-Da Yang. "Selective and blanket liquid phase deposition of silicon dioxide on silicon nitride and tungsten silicide." Semiconductor Science and Technology 18, no. 7 (June 2, 2003): L45—L48. http://dx.doi.org/10.1088/0268-1242/18/7/103.

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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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Pizzocchero, Filippo, Peter Bøggild, and Timothy J. Booth. "Carbon mediated reduction of silicon dioxide and growth of copper silicide particles in uniform width channels." Journal of Applied Physics 114, no. 11 (September 21, 2013): 114303. http://dx.doi.org/10.1063/1.4821337.

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Horino, Yuji, Noriaki Matsunami, and Noriaki Itoh. "Effect of Ion-Irradiation on Silicide Formation in Metal-Silicon System with Interfacial Silicon Dioxide Layer." Japanese Journal of Applied Physics 24, Part 1, No. 9 (September 20, 1985): 1218–23. http://dx.doi.org/10.1143/jjap.24.1218.

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Jaso, Mark A., Steve W. Robey, and Gottlieb S. Oehrlein. "Etch Selectivity of Silicon Dioxide over Titanium Silicide Using CF 4 / H 2 Reactive Ion Etching." Journal of The Electrochemical Society 136, no. 12 (December 1, 1989): 3812–15. http://dx.doi.org/10.1149/1.2096554.

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Kappa, Mathias, Markus Ratzke, and Jürgen Reif. "Pulsed Laser Deposition of Hafnium Oxide on Silicon." Solid State Phenomena 108-109 (December 2005): 723–28. http://dx.doi.org/10.4028/www.scientific.net/ssp.108-109.723.

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Hafnium oxide films were prepared by Pulsed Laser Deposition (PLD). The influence of laser wavelength (fundamental, second and third harmonic of a Nd:YAG laser), used for evaporation, and substrate temperature on the film morphology, chemical structure and interfacial quality were investigated yielding the following results: While the laser wavelength exhibits minor influence on layer structure, the substrate temperature plays a critical role regarding morphological and chemical structure of the produced hafnium oxide / silicon stacks. Atomic Force Microscopy (AFM) images show a clear transition from smooth layers consisting of small area crystallites to very rough surfaces characterized by large craters and regular, plane features when the growth temperature was increased. These facts suggest a chemical instability which is confirmed by X-ray Photoelectron Spectroscopy (XPS). Investigations of the hafnium and silicon core level spectra indicate the occurrence of silicon dioxide and hafnium silicide in the case the samples were produced at elevated temperatures.

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Vasilenko, T. A., and A. A. Koltun. "Chemical Aspects of the Obtaining of Iron-Containing Coagulant-Flocculant from Electric Steel Melting Slag for Wastewater Treatment." Solid State Phenomena 265 (September 2017): 403–9. http://dx.doi.org/10.4028/www.scientific.net/ssp.265.403.

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The possibility of producing iron and silicon-coagulant-flocculant for purification of waste water was shown. The electric steel melting slag JSC "OMK-Steel" has been used as the starting material, in which the content of iron oxide to 25.8% and silicon dioxide is 17.6%. The optimal parameters of slag hydrochloric opening were as follows: the modification time at T = 40 °C – 1 hour, the concentration of hydrochloric acid – 1.5 N, the ratio of the solid and liquid phases of S : L = 1 : 10. In these settings the concentration of hydrosilicic acid (for silicon) will be 1532 mg/l; the concentration of iron – 1250 mg/l has a lower concentration of silicic acid in the production of the solution with increasing temperature and time of exposure. This paper examined the chemical aspects of the process of obtaining the new iron-containing coagulant-flocculant based on electric furnace slag. The results can be used to produce coagulants and flocculants using industrial waste.

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Afifah Maheran, Abdul Hamid, P. Susthitha Menon, I. Ahmad, and S. Shaari. "Application of Taguchi Method in Designing a 22nm High-k/Metal Gate NMOS Transistor." Advanced Materials Research 925 (April 2014): 514–18. http://dx.doi.org/10.4028/www.scientific.net/amr.925.514.

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This paper reports on the application of Taguchi method in modelling a 22nm gate length high-k/metal gate NMOS transistor. The Nominal-the-Best Signal-to-noise Ratio (SNR) using Taguchis optimization technique was utilized to optimize the process parameters in determining the best threshold voltage (Vth) value where it was used as the evaluation variable. The high permittivity material (high-k) / metal gate device consists of titanium dioxide (TiO2) and tungsten silicide (WSix) respectively. The simulation work was executed using a TCAD simulator, which consist of ATHENA and ATLAS as a process and device simulator respectively. In this research, the Halo implantation tilting angle was identified as the most influencial factor in affecting the Vthwith a percentage of 87%, followed by the oxide growth anneal temperature (8%), the metal gate anneal temperature (4%) and lastly the Halo implantation dose (1%). As a conclusion, the Halo tilting angle is the dominant factor in optimizing the process parameter. Meanwhile the Halo implantation dose can be considered as an adjustment factor in order to achieve the target Vthvalue of 0.289 V which is in line with projections made by the International Technology Roadmap for Semiconductors (ITRS).

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Li, Jian, and J. W. Mayer. "Refractory Metal Nitride Encapsulation for Copper Wiring." MRS Bulletin 18, no. 6 (June 1993): 52–56. http://dx.doi.org/10.1557/s0883769400047333.

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Recent interest in copper-based metallization for ultra fast logic devices has stimulated extensive studies on thermal stability issues, as well as the search for novel deposition and etching processes. In copper wiring technology, thermal stability problems include: (1) rapid diffusion of copper into dielectric substrates, (2) low-temperature reaction with most near-noble metals and their silicides, (3) the susceptibility of copper to oxidation, (4) poor adhesion characteristics of copper on most dielectric materials, and (5) thermal-stress-induced void formation and cracking. The basic issues have been summarized in a recent review.When copper is in contact with a silicon substrate, copper can diffuse into active regions of devices where it becomes a recombination-generation center. In addition, copper forms the silicide Cu3Si by reacting with the substrate at temperatures less than 200°C. After the formation of the Cu3Si phase, the underlying silicon in the Cu3Si/Si structure is readily oxidized even at room temperature. In the case of copper in contact with silicon dioxide under bias thermal stress (BTS), copper is found at the SiO2/Si interface under a positive electric field. Copper diffusion in doped glass, e.g., phosphosilicate glass and silicon nitride films, is a factor at temperatures below 400°C.

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Reynes, Javier F., Guy Mercier, Jean-François Blais, and Louis-César Pasquier. "Feasibility of a Mineral Carbonation Technique Using Iron-Silicate Mining Waste by Direct Flue Gas CO2 Capture and Cation Complexation Using 2,2′-Bipyridine." Minerals 11, no. 4 (March 26, 2021): 343. http://dx.doi.org/10.3390/min11040343.

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Mineral carbonation is gaining increasing attention for its ability to sequester CO2. The main challenge is doing it economically and energy-efficiently. Recently, many studies have focused on the aqueous reaction of carbon dioxide with the alkaline earth minerals such as serpentine, Mg-rich olivine and wollastonite. Nevertheless, Fe-rich olivines have been poorly studied because of their high energy demand, which make them unfeasible for industrial implementation. This article describes the feasibility of an indirect mineral carbonation process using silicic, Fe-rich mining waste with direct flue gas CO2 via iron complexation using 2,2′-bipyridine. The overall process was performed in three main steps: leaching, iron complexation, and aqueous mineral carbonation reactions. The preferential parameters resulted in a recirculation scenario, where 38% of Fe cations were leached, complexed, and reacted under mild conditions. CO2 uptake of 57.3% was achieved, obtaining a Fe-rich carbonate. These results are promising for the application of mineral carbonation to reduce CO2 emissions. Furthermore, the greenhouse gas balance had a global vision of the overall reaction’s feasibility. The results showed a positive balance in CO2 removal, with an estimated 130 kg CO2/ton of residue. Although an exhaustive study should be done, the new and innovative mineral carbonation CO2 sequestration approach in this study is promising.

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Rutkauskas, Aurimas, and Giedrius Girskas. "LITHUANIAN QUARRY AGGREGATES CONCRETE EFFECTS OF ALKALINE CORROSION TESTS / LIETUVOS KARJERŲ UŽPILDŲ POVEIKIO BETONO ŠARMINEI KOROZIJAI TYRIMAI." Mokslas – Lietuvos ateitis 7, no. 5 (February 2, 2016): 551–56. http://dx.doi.org/10.3846/mla.2015.848.

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Aggregate alkaline corrosion of cement in concrete is going to respond in sodium and potassium hydroxide (lye) with active SiO2 found in some aggregates. During this reaction, the concrete has resulted in significant internal stresses which cause deformation of the concrete, cracking and disintegration. The reaction is slow and concrete signs of decomposition appear only after a few months or years. The study used two different aggregates quarries. Studies show that Lithuania gravel contaminated with reactive particles having amorphous silicon dioxide reacting with cement in sodium and potassium hydroxide and the resulting alkaline concrete corrosion. It was found that, according to AAR 2 large aggregates include Group II – potentially reactive because of their expansion after 14 days, higher than 0.1%. Užpildų šarminė korozija betone vyksta reaguojant cemente esantiems natrio ir kalio hidroksidams (šarmams) su aktyviu SiO2, esančiu kai kuriuose užpilduose. Vykstant šiai reakcijai betone susidaro didelių vidinių įtempių, kurie sukelia betono deformacijas, pleišėjimą ir suirimą. Reakcija vyksta lėtai, betono irimo požymių atsiranda tik po kelių mėnesių ar metų. Tyrimams buvo naudojami dviejų skirtingų karjerų užpildai. Atlikus tyrimus nustatyta, kad Lietuvos žvyro karjerai užteršti reaktyviomis dalelėmis, turinčiomis amorfinio silicio dioksido, reaguojančio su cemente esančiais natrio ir kalio šarmais, ir sukeliančiomis betono šarminę koroziją. Nustatyta, kad pagal AAR 2 stambieji užpildai priskiriami II grupei – galimai reaktyviems užpildams, nes jų plėtra po 14 parų viršija 0,1 %.

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Sheu, Lien Lung, Zbigniew Karpinski, and Wolfgang M. H. Sachtler. "Effects of palladium particle size and palladium silicide formation on Fourier transform infrared spectra and carbon monoxide adsorbed on palladium/silicon dioxide catalysts." Journal of Physical Chemistry 93, no. 12 (June 1989): 4890–94. http://dx.doi.org/10.1021/j100349a042.

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31

Atan, Norani, Burhanuddin Bin Yeop Majlis, Ibrahim Bin Ahmad, and K. H. Chong. "Influence of optimization of control factors on threshold voltage of 18 nm HfO2/TiSi2 NMOS." Indonesian Journal of Electrical Engineering and Computer Science 14, no. 1 (April 1, 2019): 295. http://dx.doi.org/10.11591/ijeecs.v14.i1.pp295-302.

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<span>This paper presents the influence of control factors as the process in development of 18 nm gate length NMOS transistor. The threshold voltage (VTH) can be minimized by optimal the control factors. Five control factors were selected through experiments. They are Adjustment VTH Implantation, Compensation Implantation, Compensation Energy Implantation, Source/Drain Implantation and Halo Implantation. While the two noise factors were introduced which are Phosphor Silicate Glass (PSG) temperature and Boron Phosphor Silicate Glass (BPSG) temperature to complete the combination with five control factors in process of Taguchi method L27 orthogonal array. The purpose of this research is to find the best value of interaction between combination controls factors and noise factors to achieve the best point of threshold voltage. In CMOS design, the threshold voltage is the benchmarking of physical parameter for determining the functional of transistor. The Virtual Wafer Fabrication SILVACO software was used to fabricate the 18 nm NMOS device. Hafnium Oxide (HfO2) and Titanium dioxide (TiO2) were utilized as the high-K materials and the Titanium Silicide (TiSi2) was utilized as metal gate. The statistics data are from the signal noise ratio (SNR) with nominal-the best (NTB) and the analysis of variance (ANOVA) of L27 orthogonal array are executed to minimize the variance of threshold voltage. The results show that the optimization and interaction method is achieved to perform the threshold voltage value with least variance is 0.3055 volts while the target value that is 0.302 ± 12.7% volts from value recommendation by the International Roadmap for Semiconductor prediction 2012.</span>

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Liu, Qilin. "New Water Treatment Chemical PFZSS Preparation and Application." Open Chemical Engineering Journal 9, no. 1 (October 9, 2015): 121–24. http://dx.doi.org/10.2174/1874123101509010121.

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Nowadays global water quality pollution has become extremely serious, and solving water pollution has been extremely urgent, so researches on water pollution solutions have become even urgent. And flocculating method is the most traditional water purification method, research and create new high performance flocculating agent is one of flocculating method inherent problems. The paper mainly describes adding iron, zinc two kinds of metal captions together in polysyllabic acid, well controlling all aspects requirements in technology, researching and creating new water purification substance—poly iron and zinc silicate sulfate flocculants (PFZSS). PFZSS making method is weighting proper amount sodium silicate into container, and meanwhile putting it into water to dissolve, then utilizing dilute euphoric acid and sodium hydroxide to adjust silicic acid solution pH value and arrive at regulated scope, letting it to activate and arrive at certain time, slowly importing activated proper silica acid solution into moderate iron sulfate and zinc sulfate on the condition of fully blending, and finally putting and curing for a while. And implement experiment research on how mixed solution metal cations matching; making method, pH value, and silicon dioxide concentration these factors affect PFZSS overall performance. PFZSS application mainly takes catering industry sewage solution as an example to get PFZSS has very strong absorption capacity, owns good cleaning effects on extremely turbid catering industry treatment sewage COD and turbidity acquiring, its reaction formed flock density is great, sedimentation rate is very fast, so PFZSS will have great application prospects in the aspect of treating urban sewage.

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Ribas-Ribas, M., G. L. Cripps, M. Townend, A. J. Poulton, and T. Tyrrell. "Spatial patterns of phytoplankton composition and upper-ocean biogeochemistry do not follow carbonate chemistry gradients in north-west European Shelf seas." ICES Journal of Marine Science 74, no. 4 (May 1, 2017): 965–77. http://dx.doi.org/10.1093/icesjms/fsx063.

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A key difficulty in ocean acidification research is to predict its impact after physiological, phenotypic, and genotypic adaptation has had time to take place. Observational datasets can be a useful tool in addressing this issue. During a cruise in June–July 2011, measurements of upper-ocean biogeochemical variables, climatically active gases and plankton community composition were collected from northwestern European seas. We used various multivariate statistical techniques to assess the relative influences of carbonate chemistry and other environmental factors on these response variables. We found that the spatial patterns in plankton communities were driven more by nutrient availability and physical variables than by carbonate chemistry. The best subset of variables able to account for phytoplankton community structure was the euphotic zone depth, silicic acid availability, mixed layer average irradiance, and nitrate concentration (59% of variance explained). The spatial variations in phytoplankton and coccolithophores species composition were both found to be more strongly associated with nutrients and physical variables than carbonate chemistry, with the latter only explaining 14 and 9% of the variance, respectively. The plankton community composition and contribution of calcifying organisms was not observed to change under lower calcite saturation state (Ω) conditions, although no regions of undersaturation (Ω < 1) were encountered during the cruise. Carbonate chemistry played a more prominent, but still secondary, role in determining dinoflagellate and diatom assemblage composition (20 and 13% of total variance explained, respectively). Nutrient and physical variables also explained more of the spatial variations of most climatically active gases and selected biogeochemical response variables, although some also appeared to be influenced by carbonate chemistry. This observational study has demonstrated that ocean acidification research needs to be set in context with other environmental forcing variables to fully appreciate the primary, or indeed secondary, role that increasing fugacity of carbon dioxide has on biological communities and associated biogeochemical rates.

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Loganina, Valentina I., and Erkebulan B. Mazhitov. "Regularities of formation of adhesive contact “sol-silicate paint - substrate”." Vestnik MGSU, no. 1 (January 2019): 94–101. http://dx.doi.org/10.22227/1997-0935.2019.1.94-101.

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Introduction. The use as a binder in the manufacture of silicate paints polysilicate solutions obtained by mixing liquid glass and silica sol is considered. To regulate the rheological properties of the paint, improve the filling and prevent the pigment part from sagging, it has been proposed to introduce glycerin into the binder composition. The results of studying the interfacial interaction between the paint and the substrate are given. Materials and methods. In developing the formulation of silicate paints based on polysilicate solutions, MK-2 microcalcite, marshalite, diatomite and talc of MT-GSM grade were used as a filler, and titanium dioxide as a pigment. Polysilicate solutions were obtained by reacting stabilized solutions of colloidal silica (sols) with aqueous solutions of alkali silicates (liquid glasses). Nanosil 20 and Nanosil 30 silicic acid sol were used, produced by the Promsteklocentr PC. Used potassium liquid glass with module M = 3.29. A thermodynamic method was used to assess the interfacial interaction. Results. Shown that the introduction of glycerol into the formulation of a sol of silicate paint promotes a decrease in the interfacial surface tension and a better wetting of the surface of the mortar substrate. An increase in wetting coefficient is observed. Coatings based on sol silicate paints with the addition of glycerin are characterized by increased crack resistance. An increase in tensile strength, maximum tensile properties, and decrease in the elastic modulus of paint membranes based on the composition with glycerol has been established. The values of the free surface energy of the coating based on the sol of silicate paint and the ratio of the polar to the dispersion component of the free energy of the surface are given. Coatings based on sol of silicate paint with the addition of glycerin are characterized by a large value of the free energy of the surface. In the process of moistening a decrease in the free surface energy is observed due to a decrease in the dispersion component. Conclusions. Studies have shown that the introduction of an additive of glycerin in the formulation of a silicate paint sol contributes to an increase in the performance properties of coatings based on it.

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Todhunter, John A., and Michael G. Farrow. "Current Scientific Considerations in Regard to Defining a “Silicone Syndrome”/Disease and the Formation of Silica from Silicone." International Journal of Toxicology 17, no. 4 (June 1998): 449–63. http://dx.doi.org/10.1080/109158198226279.

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Whether the constellation of various symptoms reported in various case-study reports on some patients who have had augmentation mammoplasty with silicone implants reflects a distinct, novel “silicone syndrome”or disease is important to settingproper endpoints for the epidemiological study of this patient population. To date, epidemiology studies on breast implant patients have focused on end-points which are typical of connective tissue disease, rheumatoid disease, and/ or autoimmune disorders. The consensus at this time, as was recently stated in a paper authored by Food and Drug Administration (FDA) personnel, is that the weight of the evidence from existing epidemiology studies is that silicone breast implants do not appreciably, if at all, increase the risk of these types of diseases. Critics of the epidemiology database have countered that had the analysis of association in these studies been done for a “silicone syndrome,” as opposed to the disease types which were analyzed, an association between silicone breast implantation and increased risk of “silicone syndrome” would have been observed. In the present analysis, this question is approached from two directions: First, the available single or multi-patient case reports available in the open literature were evaluated. The objective was to define those symptoms/ complaints that were reported in all studies or in at least 50% of the patients reported and to assign frequency distributions to individual symptoms or complaints reported in breast implant patients presenting for various complaints. By definition, if a “silicone syndrome” exists, then it can only be characterized by those symptoms or complaints which appear with regular frequency in patients so afflicted. Second, the symptoms or complaints which were used as criteria in the existing epidemiology studies were correlated with their frequency of occurrence among single or multi-patient case-reported breast implant patients. The working hypothesis in this present study is that if the number of “silicone syndrome” symptoms or complaints that also are symptoms of the existing epidemiology endpoints is large, then a distinct “silicone syndrome” is not likely to exist, and it can be concluded that existing epidemiology studies have adequately addressed the relevant issues. Also, to the extent that the frequency of symptom occurrence in “silicone syndrome” is similar to the distribution seen for known connective tissue, rheumatoid, and/ or autoimmune diseases, this will then add to the weight of evidence that no distinct “silicone syndrome” needs be postulated. Conversely, if a different set of symptoms or complaints occurs in silicone breast-implanted patients than is seen in patients with connective tissue diseases, this will argue that a distinct syndrome may exist. In the present study, the more recent suggestion that silicone may be broken down to silica in the body, and evidence for and against this suggestion are also discussed. The present analysis does not support the contention that a distinct “silicone syndrome” exists, but does support the contention that the disease endpoints used in existing epidemiology studies are adequate for examining the patient population. Also, consideration of the chemistry of silicone and its potential hydrolysis or oxidative cleavage indicates that if such reactions occur in the body at any significant rate, the product will be silicic acid, a normal and necessary constituent of the body, and not silica (i.e., silicon dioxide).

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David Theodore, N., F. Secco d'Aragona, and Scott Blackstone. "Morphology of Si/Tungsten-Silicide/Si Interlayers." MRS Proceedings 238 (1991). http://dx.doi.org/10.1557/proc-238-555.

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ABSTRACTTungsten and tungsten-silicides are of interest for semiconductor technology because of their refractory nature, low electrical-resistivity and high electromigration-resistance. This paper presents the first formation of buried tungsten-silicide layers in silicon, by proximity adhesion. The interlayers, created by a combination of chemical vapor-deposition (CVD) and proximity-adhesion were studied using transmission electron-microscopy (TEM). The behavior of the layers in the presence and absence of an adjacent silicon-dioxide interlayer was also investigated. Buried suicide layers were successfully formed with or without the adjacent silicon-dioxide. The suicide formed continuous layers with single grains encompassing the width of the interlayer. Individual grains were globular, with cusps at grain boundaries. This caused interlayer-thicknesses to be non-uniform, with lower thickness values being present at the cusps. Occasional voids were observed at grain-boundary cusps. The voids were smaller and less frequent in the presence of an adjacent oxide-layer, due to flow of the oxide during proximity adhesion. Electron-diffraction revealed a predominance of tungsten-disilicide in the interlayers, with some free tungsten being present. Stresses in the suicide layers caused occasional glide dislocations to propagate into the silicon substrate beneath the interlayers. The dislocations propagate only ∼100 nm into the substrate and therefore should not be detrimental to use of the buried layers. Occasional precipitates were observed at the end of glide-loops. These possibly arise due to excess tungsten from the interlayer diffusing down the glide dislocation to finally precipitate out as tungsten-silicide.

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da Silva, Ana Neilde Rodrigues, Rogerio Furlan, and J. J. Santiagoaviles. "Formation of Titanium Silicide Strap Lines by the Deposition of a Double Layer of Amorphous Silicon - Titanium." MRS Proceedings 402 (1995). http://dx.doi.org/10.1557/proc-402-125.

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AbstractThe reaction between an amorphous silicon film, with a titanium film, yields the formation of a titanium silicide film useful in the fabrication of local interconnection lines (straps) for integrated circuits. In this work we look at the influence of the films thickness ratios on the silicide formation on silicon dioxide. For structures with 70 or 80 nm of amorphous silicon deposited on 40 nm of titanium, we found that after a low temperature treatment of 650 °C, nominally utilized in the first processing step for the formation of self-aligned silicides, the formation of the metastable TiSi2 (C 49) and Ti5Si3 phases occurs. For silicon rich structures i.e.. 90 nm of amorphous silicon on 40 nm of titanium, besides the stable TiSi2 (C54) the metastable phases mentioned above are also detected. In this case strong morphological changes, and silicon precipitates are observed.

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38

Jang, Yoo-Sung, and Jong-Hwan Yoon. "Charge Storage Properties of Nickel Silicide Nanocrystal Layer Embedded in Silicon Dioxide." MRS Proceedings 1160 (2009). http://dx.doi.org/10.1557/proc-1160-h04-04.

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AbstractMemory properties of nickel silicide nanocrystal monolayers embedded in silicon dioxide have been investigated. The nanocrystal layers were produced by thermal annealing of a sandwich structure comprised of ultrathin Ni film (0.2 nm) sandwiched between two silicon-rich oxide (SiO1.57) layers. Average diameter and areal density is about 2.9 nm and 1.3×1012 cm-2, respectively. Capacitance-voltage (C-V) measurements are shown to have C-V characteristics suitable for nonvolatile memory applications, including large memory window (∼ 10 V), long retention time ( > 107 s), and excellent endurance ( > 106 program/erase cycles).

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39

Zou, Y. L., T. L. Alford, D. Adams, T. Laursen, K. N. Tu, R. Morton, and S. S. Lau. "Encapsulation of Silver Via Nitridation of Ag/Ti Bilayer Structures." MRS Proceedings 427 (1996). http://dx.doi.org/10.1557/proc-427-355.

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AbstractAg/Ti bilayer films deposited on silicon dioxide substrates were annealed in ammonia ambient in the temperature range of 400 - 600 °C. Rutherford backscattering spectrometry (RBS) and Auger electron spectroscopy (AES) have shown that Ti segregates to both the surface to form a TiN(O) layer and to the Ti/SiO2 interface to form a Ti-oxide/Ti-silicide bilayer. The annealed bilayer structure had minimal Ti accumulations in Ag. Resistivity values of ˜2 μΩ-cm were obtained in encapsulated Ag bilayer films, which are comparable to that of the as-deposited. X-ray analysis confirmed the absence of intermetallic phase transformation.

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A. H., Afifah Maheran,, Menon, P. S., I. Ahmad, and S. Shaari. "Optimisation of Process Parameters for Lower Leakage Current in 22 nm n-type MOSFET Device using Taguchi Method." Jurnal Teknologi 68, no. 4 (May 15, 2014). http://dx.doi.org/10.11113/jt.v68.2994.

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In this article, Taguchi orthogonal array method was used to optimize the process parameters during the design of a 22 nm n-type Metal Oxide Semiconductor Field Effect Transistor (MOSFET) in order to decrease the leakage current (ILEAK) of the device. Titanium dioxide (TiO2) was used as the dielectric layer to replace the traditional silicon dioxide SiO2 and tungsten silicide (WSix) was used as a metal gate to replace polysilicon. The device’s fabrication and electrical characterization were executed using ATHENA and ATLAS modules from Silvaco International. Taguchi’s Power of Three Series L9 orthogonal array was used to optimize the device process parameters and to finally predict the best process parameter combination to obtain the minimum leakage current (ILEAK) using Smaller-the-Better (STB) signal-to-noise ratio (SNR). The optimization resulted in the attainment of the lowest ILEAK mean value of 0.25759 nA/µm which is in accordance to the predicted value given in the International Technology Roadmap for Semiconductors (ITRS) 2011.

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Bariatro, M., A. Fontes, J. Q. Quacchia, R. Furlan, and J. J. Santiago-Aviles. "Rapid Titanium Silicidation: A Comparative Study of two Rta Reactors." MRS Proceedings 303 (1993). http://dx.doi.org/10.1557/proc-303-95.

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ABSTRACTIn this work we studied titanium silicide formation by cosputtering onto silicon dioxide. Samples deposited with various (Si/Ti) atomic ratios were analyzed by Rutherford Backscattering Spectrometry (RBS). Isocronal annealings were conducted by means of Rapid Thermal Processing (RTP) in two types of furnaces: a vacuum and an atmospheric pressure (argon). Phase formation was monitored by resistivity measurements, X-Ray diffraction (XRD), and Scanning Electron Microscopy (SEM). It is observed that the final phase formation follows the thennodynamic equilibrium diagram, determined by stoichiometry, occurring at 800°C for the vacuum furnace, and at 900°C for the atmospheric RTP furnace. Sequential thermal treatments indicated the formation of TiSi2-C49 and/or TiSi after 400°C.

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Adams, D., R. L. Spreitzer, S. W. Russell, N. D. Theodore, T. L. Alford, and J. W. Mayer. "Effectiveness of Nitride Diffusion Barriers in a Self-Encapsulated Copper-Based Metallization." MRS Proceedings 337 (1994). http://dx.doi.org/10.1557/proc-337-231.

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ABSTRACTCu(Ti 27 at. %) and Cu(Cr 26 at. %) codeposited on silicon dioxide substrates were annealed in a flowing NH3 ambient at 400 - 600°C for 30 min. The Ti segregates to both the surface to form a TiN(O) layer and to the alloy/SiO2 interface to form a Ti-oxide/Ti-silicide bilayer. The Cr seems to migrate only to the free surface to form a CrNx layer. A 45 nm - thick Al film was deposited after nitridation, whereupon a second anneal was performed to evaluate these nitride layers as diffusion barriers. It was found that the Ti-nitride was stable up to 500°C as compared to Cr-nitride at 600°C.

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Manhas, M., T. J. Pease, R. Cross, S. C. Bose, D. P. Oxley, M. M. De Souza, and E. M. Sankara Narayanan. "Device Quality SiO2 Films by Liquid Phase Deposition (LPD) AT 48°C." MRS Proceedings 716 (2002). http://dx.doi.org/10.1557/proc-716-b7.9.

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AbstractWe describe the preparation, properties and the comparison of SiO2 films deposited by liquid phase deposition from supersaturated solutions with both silica powder and silicic acid. From each solution the resulting [Si (OH)4]-rich supersaturated solution, when suitably diluted with De-Ionised (DI) water deposits SiO2 onto silicon. Our work was motivated by the search for the optimum condition for device quality oxide growth within a low (<300°C) thermal budget, for large area device fabrication, on inexpensive substrates such as glass and plastic. The net growth of the LPD of the oxide layer is result of competition between deposition and etching; the balance and hence the rate of growth being controlled simply and reproducibly by the addition of de-ionised (DI) water. We have produced device grade SiO2 from the solution at 48°C onto both n and p type Si substrates. Control of the oxide properties is achieved in the amount of DI water added to the super-saturated solution. Oxide layers of optimum quality being obtained by the titration of 60ml DI water to 100ml of supersaturated solution. FTIR, ellipsometery, and C-V/I-V measurements were used to characterise the films deposited from solutions of silica powder and silicic acid. The resistivity of the optimum layers from a saturated solution of silica powder was found to be of the order of ≈1011 Ωcm with breakdown field strengths of the order of 3-5 x 106 V/cm. The resistivity of the optimum layers prepared using silicic acid were much higher (1015 Ω-cm), with breakdown field strengths of the order of (9±1) x 106 V/cm. The results approach those for thermally grown silicon dioxide, suggesting that LPD oxide have the potential of device quality insulator on large area substrate.

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Salawu, Abdulhameed, Asuku S. Shuaibu, Memunat Tairu, Medinat O. Olabode, Bright O. Agada, and Temitope J. Adegoke. "Investigating Possibilities of fueling NIRR-1 with Low Enriched Uranium Silicide-Aluminum Dispersion Fuels." FUOYE Journal of Engineering and Technology 6, no. 1 (March 23, 2021). http://dx.doi.org/10.46792/fuoyejet.v6i1.577.

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In the last quarter of 2018, low enriched uranium dioxide fuel with zirconium alloy cladding was used successfully to convert the core of NIRR-1 from HEU to LEU fuel and the removed core returned to the country of origin. The objective of this study was to investigate the possibility of fueling the same system with alternate LEU fuel for future replacement of the current fuel, without any unacceptable compromise in reactor performance. Having more than one fuel options available for the same reactor system will present Nigeria an opportunity of making good economic decisions at the end of the cycle of the current LEU fuel. The performance of low enriched uranium silicide aluminum dispersion fuels in the core of NIRR-1 has been investigated and the results were identical with that of similar studies conducted elsewhere for generic MNSR system. Some of the calculated reactor parameters using this alternate LEU fuel were closely identical with that of the old HEU core. The computer software selected for this studies were the SCALE code system and the VENTURE PC. While the SCALE code system was employed to generate a properly averaged multigroup cross section library for the investigated LEU core models for NIRR-1 system, the VENTURE PC was utilized to give criticality information, few group fluxes and power density distributions within the core of the modeled system.Keywords— Reactor, Reactivity, Fuel, Enriched, Silicide

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"Calcium silicate and silicon dioxide/silicic acid gel added for nutritional purposes to food supplements." EFSA Journal 7, no. 6 (June 2009). http://dx.doi.org/10.2903/j.efsa.2009.1132.

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Chambers, James J., and Gregory N. Parsons. "Physical and Electrical Properties of Yttrium Silicate Thin Films." MRS Proceedings 611 (2000). http://dx.doi.org/10.1557/proc-611-c1.6.1.

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ABSTRACTThis article reports on the physical and electrical properties of yttrium silicate, which is a possible high-k replacement for the SiO2 gate dielectric in CMOS devices. The yttrium silicate (Y-O-Si) films are formed by sputtering yttrium onto clean silicon, annealing in vacuum to form yttrium silicide and then oxidizing in N2O to form the silicate. Shifts in the Y 3d, Si 2p and O 1s photoelectron spectra with respect to Y2O3 and SiO2 indicate that the films are fully oxidized yttrium silicate. FTIR results that reveal a Si-O stretching mode at 950 cm−1 and Y-O stretching modes in the far-IR are consistent with XPS. XPS and FTIR results are in accordance with the donation of electron density from the yttrium to the Si-O bond in the silicate. The yttrium silicate films contain a fixed charge density of ∼9×1010 cm−2 negative charges as calculated from measured C-V behavior. The properties of ultra-thin yttrium silicate films with an equivalent silicon dioxide thickness (electrical) of ∼1.0 nm will be discussed elsewhere.

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Smolinsky, Gerald, and Vivian Ryan. "Spin-on Silicon Oxide (Sox): Deposition and Properties." MRS Proceedings 131 (1988). http://dx.doi.org/10.1557/proc-131-563.

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ABSTRACTHigh quality SiO2 films are obtained by spin-coating wafers with a sol/gel of silicic acid in either a 2, 3, or 4-carbon linear-aliphatic alcohol. Some properties of the deposited film depend upon the solvent: such as density, tensile stress, and infrared spectrum. However, Rutherford-back-scattering analysis indicates the O:Si ratio (2.00±05) to be independent of the solvent. The infrared spectrum of the oxide exhibits Si-OSi absorption in the range 1070–1080 cm.−1 depending on the curing temperature and solvent system. (The weaker Si-OSi band is found at 804–810 cm.−1) In addition, low-temperature-cured (<500 °C) films show Si–OH absorption. Films hot-plate baked at 150–350 °C are stable but not fully cured. Films from propanol baked at 400 °C have a refractive index of 1.41–1.42 and a wet-etching rate in 30:1 BOE of ˜1250 Å/min. Films cured at 900 °C have a refractive index of 1.42–1.43, a wet-etching rate of ˜430 A/min, and are more dense by a factor of ˜1.25. Dry-etching with CHF3/O2 occurs at rates comparable to those of CVD oxides. Multiple applications lead to crack-free films as thick as 0.6–0.8 μ m. Deposition over aluminum-patterned topography results in a smoothing of the surface and suppression of hillock growth in the aluminum even after a 450 °C cure. SOX adheres to silicon, aluminum, and silicon dioxide. A boron-doped SOX is readily prepared.

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Chida, Taiji, Yuichi Niibori, Osamu Tochiyama, Hitoshi Mimura, and Koichi Tanaka. "Dissolution Rate of Colloidal Silica in Highly Alkaline Solution." MRS Proceedings 824 (2004). http://dx.doi.org/10.1557/proc-824-cc8.39.

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AbstractFor the performance assessment of the radioactive waste repository, it is important to clarify the dynamic behavior of silica (silicic acid and hydrous or unhydrous silicon dioxides). The behavior of silica would be complicated when cement is used for the construction of the repository, since silica takes various forms due to polymerization, precipitation and dissolution with change of pH or temperature. In order to know the fundamental kinetic property of silica, this study has examined the dissolution rate of colloidal-silica.In the experiment, the concentration of silica in a soluble form was determined by the silicomolybdenum-yellow method. In this study, soluble-silica was defined as silica reacting with molybdate reagent and coloring yellow, and colloidal-silica was defined as silica in liquid phase except for soluble-silica. Colloidal-silica was obtained through the polymerization process, where the pH value of silica solution was brought down from over 10 by HNO3 solution. This study examined dissolution rate of colloidal-silica again by setting to 10 or 13 in pH-value and 288 K, 298 K or 313 K in temperature. In the experimental results, the dissolution reaction of colloidal-silica proceeded linearly with time, when the dissolution of colloidal silica was not restricted by the solubility of silica. To estimate the dissolution rate, we assumed df /dt = k*, where f is the soluble-silica fraction defined as the amount of soluble-silica divided by the silica amount introduced into the sample solution, t the time (s) and k* the rate constant (s-1). The activation energy for the dissolution of the colloidal-silica at pH 13 was estimated to be approximately 80 kJ·mol-1which was similar to that for amorphous silica (solid phase) at pH 13. This suggests the same reaction mechanism for the dissolution of colloidal-silica and amorphous silica in highly alkaline solution.

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Journal articles on the topic 'Dioxyde de silicium'

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