Silicon-processing technology oxides

CVD processing can be used to provide selective deposition on certain areas of a surface. Selective tungsten CVD is used to fill vias or holes selectively through silicon oxide layers in silicon-device technology. In this case, the silicon from the substrate catalyzes the reduction of tungsten hexafluoride, whereas the silicon oxide does not. Selective CVD deposition can also be accomplished using lasers or focused electron beams for local heating. 

Planar processing technology derives its success from the ability to grow high quality, passivating insulators on the semiconductor surface. This is particularly true in the case of silicon technology, where the thermal oxidation of silicon in oxygen and/or steam at 1000°-1200°C is used almost exclusively to... 

Semiconductor processing technologies have often been used to produce ISEs, particularly as field-effect transistors (FETs) with ion-selective layers like silicon oxide over the gate region. Such ion-selective FETs (ISFETs) are, in principle, solid ISEs, although sometimes the dielectric over the gate is covered with a second, liquid membrane-type layer to achieve different selectivities. 

Dubbe A (2003) Fundamenteils of solid state ionic micro gas sensors. Sens Actuators B 88 138-148 Glocker DA, Shah 1 (eds) (1995) Handbook of thin film process technology. Institute of Physics, Bristol, UK Hecht G, Richter F, Heihn J (eds) (1994) Thin films. DGM InformationgesseUschaft, Oberursel, Germany Hitchman ML, Jensen KF (1993) CVD principles tmd applications. Academic, San Diego, CA Hubbard KJ, Schlom DG (1996) Thermodyntunic stabdity of binary oxides in contad with silicon. J Mater Res 11 2757-2776... 

In recent development of the semiconductor industries, thermal oxide film thickness of less than 5 nm has been used in semiconductor devices such as metal-oxide-semiconductor (MOS) structures. Thickness of less than 5 nm is almost near the thickness of a native oxide film on the surface of silicon wafer. Therefore the characterization of ultra thin native oxide film is important in the semiconductor process technology. The secondary electron microscopy (SEM), the scanning Auger electron microscopy (SAM), the atomic force microscopy (AFM) and the X-ray photoelectron spectroscopy (XPS) might be the useful characterization method for the surface of the silicon wafers. 

According to our experimental results [37], selectivity may be achieved by gas-phase catalyst delivery [38 0] on lithographically machined planar and nonplanar templates consisting of oxidized silicon surfaces. Our bottom-up fabrication approach is easy to carry out, scalable to large areas, and compatible with standard silicon microfabrication technology. In this specific CVD process, nanotube structures are designed and built first on planar patterns composed of SiOa and Si most of the substrates used in this study were Si(lOO) wafers capped with a lOO-nm-thick silica layer, however, below we discuss the case of thick silica layers (up to 8.5 M-m). 

Chemical vapor deposition (C VD) is a versatile process suitable for the manufacturing of coatings, powders, fibers, and monolithic components. With CVD, it is possible to produce most metals, many nonmetallic elements such as carbon and silicon as well as a large number of compounds including carbides, nitrides, oxides, intermetallics, and many others. This technology is now an essential factor in the manufacture of semiconductors and other electronic components, in the coating of tools, bearings, and other wear-resistant parts and in many optical, optoelectronic and corrosion applications. The market for CVD products in the U.S. and abroad is expected to reach several billions dollars by the end of the century. 

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