Silicon thin-film technology

Microelectrodes are well-established instruments in medical science and diagnosis. Due to their small size, they are always used when bulky instruments fail. However, the current of a single microelectrode is very small. For that reason, we designed microelectrode arrays in silicon thin-film technology combining large overall currents with typical microelectrode features [1]. 

B. Schroder, Thin-film technology based on hydrogenated amorphous-silicon, Mater. Sci. Eng., A, 139 319-333, 1991. 

These features imply that the cost reduction potential for thin-film technology is very high and it is thus capable, in the longer term, of extending the P V learning curve beyond the point that can be reached by crystalline silicon technology. 

Still another method used to produce PV cells is provided by thin-film technologies. Thin films are made by depositing semiconductor materials on a solid substrate such as glass or metal sheet. Among the wide variety of thin-film materials under development are amorphous silicon, polycrystalline silicon, copper indium diselenide, and cadmium telluride. Additionally, development of multijunction thin-film PV cells is being explored. These cells use multiple layers of thin-film silicon alloys or other semiconductors tailored to respond to specific portions of the light spectrum. 

Micro electrode arrays can also be produced by thin film technology and silicon micromachining. Electrochemical analysis using planar thin film metal electrodes as transducer can be done with high performance in vitro [59]. 

Active-matrix displays differ from the aforementioned displays in that they have a switch incorporated into each pixel (Tsukada 2000). This removes the limitations encountered in passive matrix displays but requires more sophisticated processing equipment to be used. The dominant pixel switch technology is the amorphous silicon thin-film transistor (TFT) on glass (Tsukada 2000), although other technology... 

To reduce expense, efforts are made to exploit integrated thin film technologies. For example, arrays have been produced via thin film deposition of the pyroelectric onto a sacrificial layer, e.g. a suitable metal or polysilicon, which is then selectively etched away. Thermal isolation of the pyroelectric element is achieved through engineering a gap between it and the ROIC silicon wafer. Yias in the supporting layer permit electrical connections to be made between the detector and the wafer via solder bonds. Imaging arrays have been produced in this way incorporating sputtered PST and sol-gel formed PZT films. 

As mentioned in the introduction, nc-DSCs are expected in the short term to be available for low-power applications, competing with other thin film technologies, among which amorphous silicon is already an established technology. 

In recent years some innovative techniques for sensor preparation have been proposed thick- and thin-film technology, silicon technology, etc. they are characterized by the possibility of mass-production and high reproducibility. Among these, the equipment needed for thick film technology is less complex and less costly and thus it is one of the most used for sensor production. 

Silicon oxide is a critical source material in the oxide-assisted growth as described above. It also plays important roles, as is well known, in many fields such as electronics, optical communications, and thin-film technology. Our recent finding of silicon oxide in the synthesis of silicon nanowires, as we reviewed in the previous part of this chapter, would extend further the important new application of silicon oxide. 

The critical aspect of modern thin film technology is the growth of epitaxial layers. We illustrate the importance of epitaxial growth and strainengineering in producing light emitting films on silicon substrates. 

Placing strain gages on steel diaphragms can be done in several ways. In automotive applications up to 2000 bar three different technologies are widely used thin-film technology, microfused silicon strain gages, and a fused single chip (Fig. 7.4.5). 

In the case of glass, however, no great variations in behaviour between different types are expected because of their very similar structure and surface composition. Chemical vapour deposition reactions had already been tried by the last century, for instance in the refinement and deposition of silicon by reduction of SiF4 and SiCU with alkali metals [71] and in the refining of Ni using Ni-carbonyl in the Mond process [72,73]. The major impact of chemical vapour deposition on thin-film technology took place, starting some 60 years ago, when refractory compounds such as metal carbides, nitrides, silicides, borides and oxides as well as mixed phases of... 

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