Silicon surface technology

The understanding and control of silicon surfaces is of great importance for technological applications, since the fraction of atoms residing on or near the surface becomes significant. In the last decade, much attention has been directed... 

According to the international technology roadmap for semiconductors, chips with a wafer diameter of450 mm and a feature size of 0.05 /xm by 2011 will serve to decrease manufacturing costs [29]. In the integrated circuit (IC) manufacture process as shown in Fig. 21 [30], dielectric stacks have been formed by the ion etching on the coating of dielectric material formed on the silicon surface (Fig. 21 (a)). 

Silicon wafer has been extensively used in the semiconductor industry. CMP of silicon is one of the key technologies to obtain a smooth, defect-free, and high reflecting silicon surfaces in microelectronic device patterning. Silicon surface qualities have a direct effect on physical properties, such as breakdown point, interface state, and minority carrier lifetime, etc. Cook et al. [54] considered the chemical processes involved in the polishing of glass and extended it to the polishing of silicon wafer. They presented the chemical process which occurs by the interaction of the silicon layer and the... 

It is very clear that silicon is one of the most important materials in modern technologies, especially in electronics. Silicon is also one of most common element on the earth. Silicon surface is readily oxidized under ambient condition. A silicon substrate is covered by a silica (SiO c) layer. This silica layer can be controlled easily by chemical reagents, heating, electrochemical treatment, and so on. 

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. 

This is the most important step of microarray technology. Attachment of a single DNA molecule to a silicon surface can be done by either one of the following methods. 

An overview of the basic operation of a STM and of STM of silicon surfaces has been presented. In particular, as scanning probe technology continues to improve it has been shown that it is possible to not only image surfaces with atomic-resolution, but to controllably place and manipulate atoms... 

Topographic image of a reconstructed silicon surface showing outermost atomic positions, photograph of Dr. James Batteas. National Institute of Standards and Technology. Reproduced by permission p. 

In view of the many important applications in semiconductor technology, the interaction of hydrogen with silicon surfaces has been intensively studied. Recombinative H2 desorption from Si(100)-2 x 1 follows first-order kinetics89, unusual when compared with the second-order kinetics observed for H2 desorption from Si(lll)-7 x 7. The measured activation barriers for the desorption of H2 on Si(100) range from 45 to 66 kcalmol-189 90. 

As already mentioned, in the case of semiconductor surfaces there is often a strong surface rearrangement upon adsorption due to the covalent bonding of the semiconductor substrate. The benchmark system for the study of the adsorption and desorption dynamics at semiconductor surfaces is the interaction of hydrogen with silicon surfaces [2, 61]. Apart from the fundamental interest, this system is also of strong technological relevance for the growth and passivation of semiconductor devices. 

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