Indium films

Pocza J F, Barna A and Barna P B 1969 Formation processes of vacuum deposited indium films and thermodynamical properties of submicroscopic particles observed by in situ electron microscopy J. Vac. Sc/. Techno . 6 472... 

Treu (1976) measured transmission spectra (optical density) for indium films of the type used for immunological slides. His calculations based on Mie theory led him to the conclusion that this theory was not compatible with observations. In particular, calculations for spheres of diameter 1390 A showed a feature that was not observed in experiments. Although calculations for spheres half this size did not show this feature, the wavelength of maximum optical density was much shorter than that observed. 

To these two sets of results we can contrast the IR spectrum reported for adsorption from several torr of acetic acid gas onto oxidized indium films. This spectrum consists of two broad peaks at 1590 and 1455 cm-1, attributed to the asymmetric and symmetric carboxylate stretch. Both peaks are of roughly similar intensity. 

The electrical connection between detector elements and an input pad of a read-out circuit is improved in JP-A-6204448 by providing an indium film on the detector substrate corresponding to the input pad prior to forming a through hole. 

The increase in the intensity of light scattered from a glass surface coated with an indium film and antibody has been monitored to measure a rheuma factor (Giaever et al., 1984). The light scattering was proportional to the antigen concentration. 

J.C. Lemonnier, G. Jezequel, J. Thomas, Optical properties in the far UV and electronic structure of indium films. J. Rhys. C Solid State Rhys. 8, 2812-2818 (1975)... 

Luk S Y, Mayers F R and Williams J O 1988 Preparation and oharaoterization of Langmuir-Blodgett films of mesoporphyrin-IX dimethylester indium ohioride Thin Solid Films 157 69-79... 

Batteries. Many batteries intended for household use contain mercury or mercury compounds. In the form of red mercuric oxide [21908-53-2] mercury is the cathode material in the mercury—cadmium, mercury—indium—bismuth, and mercury—zinc batteries. In all other mercury batteries, the mercury is amalgamated with the zinc [7440-66-6] anode to deter corrosion and inhibit hydrogen build-up that can cause cell mpture and fire. Discarded batteries represent a primary source of mercury for release into the environment. This industry has been under intense pressure to reduce the amounts of mercury in batteries. Although battery sales have increased greatly, the battery industry has aimounced that reduction in mercury content of batteries has been made and further reductions are expected (3). In fact, by 1992, the battery industry had lowered the mercury content of batteries to 0.025 wt % (3). Use of mercury in film pack batteries for instant cameras was reportedly discontinued in 1988 (3). 

Copper Indium Diselenide. CuInSe2 (CIS) has proven to be one of the most promising thin-film photovoltaic materials. CIS ahoy materials have yielded smah-area (ca 1 cm ) laboratory devices with efficiencies in excess of 17% and large-area (ca 0.5 m ) monolithic integrated modules with efficiencies in excess of 11%, and have shown excehent radiation hardness. 

StiU another method used to produce PV cells is provided by thin-fiLm technologies. Thin films ate made by depositing semiconductor materials on a sohd substrate such as glass or metal sheet. Among the wide variety of thin-fiLm materials under development ate amorphous siUcon, polycrystaUine sUicon, copper indium diselenide, and cadmium teUuride. Additionally, development of multijunction thin-film PV cells is being explored. These cells use multiple layers of thin-film sUicon alloys or other semiconductors tailored to respond to specific portions of the light spectmm. 

Selenium is also used in thin-film photovoltaic cells (qv) which contain copper indium diselenide [12018-95-0] CuInSe2. Use is quite small as of 1996. However, if the United States solar energy output with such cells were to increase by 100 MW/yr, this would require 8 t of selenium aimuaHy (see... 

Spray Pyrolysis. In spray pyrolysis, a chemical solution is sprayed on a hot surface where it is pyrolyzed (decomposed) to give thin films of either elements or, more commonly, compounds (22). Eor example, to deposit CdS, a solution of CdCl plus NH2CSNH2 (thiourea) is sprayed on a hot surface. To deposit Iu202, InCl is dissolved in a solvent and sprayed on a hot surface in air. Materials that can be deposited by spray pyrolysis include electrically conductive tin—oxide and indium/tin oxide (ITO), CdS, Cu—InSe2, and CdSe. Spray pyrolysis is an inexpensive deposition process and can be used on large-area substrates. 

Fig. 12. General stmcture of LCD. A, polarizer plate B, glass plate C, electrodes (indium—tin oxide) D, Hquid crystal E, common electrode (ITO) F, overcoated layer G, colored pixel H, back light. In an improved color LCD system today, retardation films are placed between A and B.

The changes in the optical absorption spectra of conducting polymers can be monitored using optoelectrochemical techniques. The optical spectmm of a thin polymer film, mounted on a transparent electrode, such as indium tin oxide (ITO) coated glass, is recorded. The cell is fitted with a counter and reference electrode so that the potential at the polymer-coated electrode can be controlled electrochemically. The absorption spectmm is recorded as a function of electrode potential, and the evolution of the polymer s band stmcture can be observed as it changes from insulating to conducting (11). 

Contact with steel, though less harmful, may accelerate attack on aluminium, but in some natural waters and other special cases aluminium can be protected at the expense of ferrous materials. Stainless steels may increase attack on aluminium, notably in sea-water or marine atmospheres, but the high electrical resistance of the two surface oxide films minimises bimetallic effects in less aggressive environments. Titanium appears to behave in a similar manner to steel. Aluminium-zinc alloys are used as sacrificial anodes for steel structures, usually with trace additions of tin, indium or mercury to enhance dissolution characteristics and render the operating potential more electronegative. 

Although aluminium is a base metal, it spontaneously forms a highly protective oxide film in most aqueous environments, i.e. it passivates. In consequence, it has a relatively noble corrosion potential and is then unable to act as an anode to steel. Low level mercury, indium or tin additions have been shown to be effective in lowering (i.e. making more negative) the potential of the aluminium they act as activators (depassivators). Each element has been shown to be more effective with the simultaneous addition of zinc . Zinc additions of up to 5% lower the anode operating potential, but above this level no benefit is gained . Below 0 9 7o zinc there is little influence on the performance of aluminium anodes . Table 10.10 lists a number of the more common commercial alloys. 

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