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Evaporative deposition method

Thin films of CTC or RIS deposited on several substrates (e.g. glass, polymer, metal) can be prepared by the evaporation- deposition method [327,328], or the Langmuir-Blodgett technique [330,47b]. [Pg.181]

Metallization layers are generally deposited either by CVD or by physical vapor deposition methods such as evaporation (qv) or sputtering. In recent years sputter deposition has become the predominant technique for aluminum metallization. Energetic ions are used to bombard a target such as soHd aluminum to release atoms that subsequentiy condense on the desired substrate surface. The quaUty of the deposited layers depends on the cleanliness and efficiency of the vacuum systems used in the process. The mass deposited per unit area can be calculated using the cosine law of deposition ... [Pg.348]

Anode materials are most typically deposited by evaporation, sputtering, or chemical vapor deposition methods. Other methods such as screen printing, laser ablation, electrochemical deposition, etc., have also been used. [Pg.302]

Many other methods of preparation have been employed. For example, the triiodide is formed when arsenious oxide,5 or a mixture of this oxide with sulphur,6 is heated in iodine vapour or when arsenious oxide is heated with iodine,7 hydriodic acid,8 a mixture of potassium iodide and acetic acid,9 or a mixture of potassium iodide and potassium hydrogen sulphate.10 When arsenic disulphide and iodine, in the proportions 1 As Ss 3la, are heated together, arsenic triiodide is formed.11 When arsenic trisulphide is fused with an excess of iodine, the product is soluble in carbon disulphide and the solution on evaporation deposits arsenic triiodide, then a sulphiodide and finally sulphur with excess of sulphide the product is the sulphiodide, AsS2I. If a solution of iodine in carbon disulphide is added to arsenic di- or tri-sulphide, the triiodide and sulphur are formed. The triiodide is also produced when a mixture of the trisulphide and mercuric iodide is heated 12. when hydriodic... [Pg.116]

LAPS was introduced by Sato et al. [155]. The detection of heavy metal ions by thin films of chalcogenide-glass membranes using the pulsed laser deposition method (PLD) was reported by Mourzina et al. [156]. The PLD technique was also introduced to evaporate A1203 as a pH-sensitive material for LAPS devices [157]. The first practical application of the above-described LAPS card was demonstrated by Kloock et al. for a comparative study of Cd-sensitive chalcogenide glasses for ISFETs, LAPS and pISEs (ion-selective electrodes) [158]. [Pg.115]

Thin semiconductor films (and other nanostructured materials) are widely used in many applications and, especially, in microelectronics. Current technological trends toward ultimate miniaturization of microelectronic devices require films as thin as less than 5 nm, that is, containing only several atomic layers [1]. Experimental deposition methods have been described in detail in recent reviews [2-7]. Common thin-film deposition techniques are subdivided into two main categories physical deposition and chemical deposition. Physical deposition techniques, such as evaporation, molecular beam epitaxy, or sputtering, involve no chemical surface reactions. In chemical deposition techniques, such as chemical vapor deposition (CVD) and its most important version, atomic layer deposition (ALD), chemical precursors are used to obtain chemical substances or their components deposited on the surface. [Pg.468]

Thermal vacuum evaporation. This method is used for evaporation and the subsequent deposition of various metals. Rather volatile metals such as Ag, Au, Cu, and Pd can be evaporated from heated containers. Evaporation of less volatile metals, in particular, Ti or Mo, occurs by electrical heating of metal filaments or bands [32]. In certain conditions chemical active gases, such as oxygen, sulfur vapors, and others, introduced in evaporation zone react with metal atoms giving semiconductor compounds (for example, oxides, sulfides). [Pg.536]

Molecular self-organization in solution depends critically on molecular structural features and on concentration. Molecular self-organization or aggregation in solution occurs at the critical saturation concentration when the solvency of the medium is reduced. This can be achieved by solvent evaporation, reduced temperature, addition of a nonsolvent, or a combination of all these factors. Solvato-chromism and thermochromism of conjugated polymers such as regioregular polythiophenes are two illustrative examples, respectively, of solubility and temperature effects [43-45]. It should therefore be possible to use these solution phenomena to pre-establish desirable molecular organization in the semiconductor materials before deposition. Our studies of the molecular self-assembly behavior of PQT-12, which leads to the preparation of structurally ordered semiconductor nanopartides [46], will be described. These PQT-12 nanopartides have consistently provided excellent FETcharacteristics for solution-processed OTFTs, irrespective of deposition methods. [Pg.90]

Photoreceptors are prepared by the sequential application of the various layers onto a web or drum substrate. Vapor-deposition methods can be used for some pigments. Most layers, however, are coated from solution or dispersions in organic solvents. Wicks (1986) has reviewed film formation from polymer solutions. The choice of solvent is determined by such factors as solubility, evaporation rates, surface tension, toxicity, as well as environmental... [Pg.112]

Vapor deposition. Both physical and chemical vapor deposition methods can be used to prq)are dense inorganic membranes. In either process, vaporization of the membrane material to be deposited is effected by physical means (such as thermal evaporation and sputtering) or chemical reactions. [Pg.25]

Aerosol-assisted CVD introduces rapid evaporation of the precursor and short delivery time of vapor precursor to the reaction zone. The small diffusion distance between the reactant and intermediates leads to higher deposition rates at relatively low temperatures. Single precursors are more inclined to be used in AACVD therefore, due to good molecular mixing of precursors, the stoichiometry in the synthesis of multicomponent materials can be well controlled. In addition, AACVD can be preformed in an open atmosphere to produce thin or thick oxide films, hence its cost is low compared to sophisticated vacuum systems. CVD methods have also been modified and developed to deposit solid phase from gaseous precursors on highly porous substrates or inside porous media. The two most used deposition methods are known as electrochemical vapor deposition (EVD) and chemical vapor infiltration (CVI). [Pg.353]

Glass films are used in the semiconductor industry because of their dielectric properties, and are used for encapsulating integrated circuits and other electronic devices because they provide a hermetic seal. Glass films are formed by both reactive and non reactive deposition methods, (e.g., evaporation, sputtering, and ion implantation or ion platting for the latter). [Pg.245]

CVD as a deposition method for WSix has superior properties over sputtering or evaporation methods. [Pg.208]

Compared with other vapour-phase deposition methods, CVD method is perhaps the most complex. Unlike growth by physical deposition such as evaporation or Molecular Beam Epitaxy (MBE), this method requires numerous test runs to determine and reach suitable growth parameters, especially for single-crystal growth. The complexity of this method results from the following facts ... [Pg.6]

PVA, 88 mg) was mixed with 0.2 ml of HEPES buffer solution (1 x 10-2 mol dm 3 HEPES, 10 ml total) at pH 7.0 containing BCECF (5 mg) and stirred for several minutes at room temperature. The mixture was then cast on an ITO-coated quartz substrate by a spin-coating method, and water was removed by evaporation. A semitransparent aluminum (Al) film was deposited on the dried polymer film by a vacuum vapor deposition method. The ITO and Al films were used as electrodes. A sinusoidal ac voltage with a modulation frequency of 40 H z was applied to a sample polymer, and the field-induced change in fluorescence intensity was detected with a lock-in amplifier at the second harmonic of the modulation frequency. A dc component of the fluorescence intensity was simultaneously observed. [Pg.329]


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See also in sourсe #XX -- [ Pg.113 ]




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