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Film deposition conditions

The hydrodynamic model is based on a sufficiently high collision probability under thermodynamic equilibrium. This condition is fulfilled only at p > 1 mbar, i.e., at high pressures above the typical PLD film deposition conditions, or at the beginning of plasma expansion, at high plasma density (small target to substrate distance). [Pg.308]

In the present study this technique was used to determine the influence of monomer composition on polymer structure and to establish the effects of film deposition conditions. A point of particular interest was to determine whether polymers resembling those produced by conventional polymerization could be obtained by locating the substrate on which polymer deposition occurs in a region adjacent to the plasma but in minimal contact with it. These experiments were motivated by the work of O Kane and Rice ( ) which showed that the polymer obtained in a region just downstream from the plasma was more linear than polymer deposited within the plasma. [Pg.147]

In the case of electrodeposition from the solution containing P04 -ions, almost complete surface coverage was achieved even with a charge quantity of 2 mA h cm at a current density of 30 mA cm (i.e., under the optimal film deposition conditions, as determined in Ref. [65]). This is probably due to the possibility of further nucleation occurring immediately next to the already existing nuclei, as a result of the smaller values of the radii of the nucleation exclusion zones caused by the decrease of the exchange current density for the deposition process by the addition of P04 -ions. For comparison, in phosphate-free nitrate solution, a compact Ag film had not been deposited even after 100 mA h cm had been passed through the cell, as can be seen from Fig. 2.23a [65]. [Pg.67]

The deposition of titanium oxide thin-films on Mo(l 10) represents a case where the stoichiometry of the film is sensitive to the deposition conditions [4T]. It was found that both Ti02 and Ti203 thin-films could be made. [Pg.941]

Ion implantation (qv) has a large (10 K/s) effective quench rate (64). This surface treatment technique allows a wide variety of atomic species to be introduced into the surface. Sputtering and evaporation methods are other very slow approaches to making amorphous films, atom by atom. The processes involve deposition of a vapor onto a cold substrate. The buildup rate (20 p.m/h) is also sensitive to deposition conditions, including the presence of impurity atoms which can faciUtate the formation of an amorphous stmcture. An approach used for metal—metalloid amorphous alloys is chemical deposition and electro deposition. [Pg.337]

The optoelectronic properties of the i -Si H films depend on many deposition parameters such as the pressure of the gas, flow rate, substrate temperature, power dissipation in the plasma, excitation frequency, anode—cathode distance, gas composition, and electrode configuration. Deposition conditions that are generally employed to produce device-quahty hydrogenated amorphous Si (i -SiH) are as follows gas composition = 100% SiH flow rate is high, --- dO cm pressure is low, 26—80 Pa (200—600 mtorr) deposition temperature = 250° C radio-frequency power is low, <25 mW/cm and the anode—cathode distance is 1-4 cm. [Pg.359]

The Stability of the natural oxide film reinforced by the chromate ion determines the conditions of pH, ratio of activating anion to chromate, and temperature at which the oxide is broken down and a chromate film deposited. Thus magnesium alloys can be chromate-treated in nearly neutral solutions, whereas aluminium alloys can be treated only in solutions of appreciable acidity or alkalinity. [Pg.724]

The strippable films deposited from solvents in the cold are much thinner (= 0.05-0.25 mm) than those from the hot-dip materials, and their protective properties are not nearly so good. A possible difficulty which must be watched for is the development of brittleness on ageing and consequent difficulty of stripping. Latex films containing inhibitors such as sodium benzoate have been found to deteriorate under tropical conditions, but may have a use in more temperate climates. [Pg.758]

X-ray photoelectron spectroscopic (XPS) studies of Ag63,64 and Pt6,56-62 films deposited on YSZ under positive current application conditions have confirmed the proposition2-4 that NEMCA with oxide ion conducting solid electrolytes is due to an electrochemically induced and controlled backspillover of oxide ions on the catalyst surface. [Pg.247]

Figure 11.7 confirms that electrochemically induced and controlled O2 backspillover from the support to the metal film surface is the promoting mechanism both in the case of YSZ (Fig. 11.7a) and in Ti02 (Fig. 11.7b). These figures show the Ols spectrum of the Pt film deposited on YSZ and on TiC>2, first under open-circuit conditions (Fig. 11.7aC, 11.7bA) and then under positive current and potential application (Fig. 11.7aB, 11.7bB). Figures 11.7aC and 11.7bC show the difference spectra. In both cases, XPS clearly shows the presence of the O2 double layer, even under open-circuit conditions (Figs. 11.7aA, 11.7bA) and also clearly confirms the electrochemically controlled backspillover of O2 from the YSZ orTi02 support onto the catalyst surface. Note that the binding energy of the backspillover O species is in both cases near 529 eV, which confirms its strongly anionic (probably O2 ) state.31,32... Figure 11.7 confirms that electrochemically induced and controlled O2 backspillover from the support to the metal film surface is the promoting mechanism both in the case of YSZ (Fig. 11.7a) and in Ti02 (Fig. 11.7b). These figures show the Ols spectrum of the Pt film deposited on YSZ and on TiC>2, first under open-circuit conditions (Fig. 11.7aC, 11.7bA) and then under positive current and potential application (Fig. 11.7aB, 11.7bB). Figures 11.7aC and 11.7bC show the difference spectra. In both cases, XPS clearly shows the presence of the O2 double layer, even under open-circuit conditions (Figs. 11.7aA, 11.7bA) and also clearly confirms the electrochemically controlled backspillover of O2 from the YSZ orTi02 support onto the catalyst surface. Note that the binding energy of the backspillover O species is in both cases near 529 eV, which confirms its strongly anionic (probably O2 ) state.31,32...
The ionized forms of polypeptides exhibit many characteristics in common therefore, we have studied them under various conditions. The most interesting observation is the transition of a polyelectrolyte brush found by changing the polyelectrolyte chain density. The brush layers have been prepared by means of the LB film deposition of an amphiphile, 2C18PLGA(48), at pH 10. Mixed monolayers of 2C18PLGA(48) and dioctadecylphos-phoric acid, DOP, were used in order to vary the 2C18PLGA(48) content in the monolayer. [Pg.13]

It was reported recently [216] that optical-quality PbTe thin films can be directly electrodeposited onto n-type Si(lOO) substrates, without an intermediate buffer layer, from an acidic (pH 1) lead acetate, tellurite, stirred solution at 20 °C. SEM, EDX, and XRD analyses showed that in optimal deposition conditions the films were uniform, compact, and stoichiometric, made of fine, 50-100 nm in size, crystallites of a polycrystalline cubic structure, with a composition of 51.2 at.% Pb and 48.8 at.% Te. According to optical measurements, the band gap of the films was 0.31 eV and of a direct transition. Cyclic voltammetry indicated that the electrodeposition occurred via an induced co-deposition mechanism. [Pg.127]


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See also in sourсe #XX -- [ Pg.125 ]




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Conditioning film

Deposited films

Deposition conditions

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