Nanoelectronic devices

The aim of this chapter is to acquaint the reader the physical principles of SE tunneling devices to be used in nanoelectronics. Based on this the charge transport properties of nanocluster assemblies in one, two and three dimensions will be discussed. By means of selected examples it will be demonstrated that ligand-stabilized nanoclusters of noble metals may be suitable building blocks for nanoelectronic devices. 

Investigations of the kinetics of hole transfer in DNA by means of pulse radiolysis of synthetic ODNs have provided details about the hole transfer process, especially over 1 /is, including the multi-step hole transfer process. Based on the investigation of the kinetics of hole transfer in DNA, development of the DNA nanoelectronic devices is now expected. An active application of the hole transfer process is also desirable from a therapeutical point of view, since hole transfer may play a role in improvement of quantum yield and selectivity of DNA scission during photodynamic therapy. The kinetics of the hole transfer process is now being revealed, although there is still much research to be performed in this area. The kinetics of adenine hopping is another area of interest that should be explored in the future. 

Because DNA is much more stable under reductive conditions, excess electron transfer may in the future, open the door to side reaction free chemistry at a distance, and may pave the way for DNA-based nanoelectronics devices. 

After the discovery by Fischer and Maasbol of the first stable carbene complexes in 1964, i.e., [(CO)5W =C(OMe)R ] [21], generation of related metaUacumulene derivatives [M]=C(=C) =CR2 (n > 0) was obviously envisaged. Thus, it is presently well-established that stabilization of these neutral unsaturated carbenes by coordination to a transition metal center is possible by the use of the lone pair of electrons on the carbenic carbon atom, via formation of a metal-carbon a-bond (electron back-donation from the metal fragment to the carbon ligand may strengthen this bond). This has allowed the development of a rich chemistry of current intense interest due to the potential applications of the resulting metallacumulenic species in organic synthesis, as well as in the construction of molecular wires and other nanoelectronic devices [22]. 

Becerril HA, Stoltenberg RM, Wheeler DR, Davis RC, Harb JN, Woolley AT. DNA-templated three-branched nanostructures for nanoelectronic devices. J Am Chem Soc 2005 127 2828-2829. 

The fifth contribution by M. Putkonen and L. NiinistO presents an overview of Organometallic Precursors for Atomic Layer Deposition (ALD). The key principle of ALD in contrast to CVD is the exclusion of any gas-phase prereaction allowing the thin film growth to be fully controlled by surface reactions and adsorption/desorption kinetics. ALD is thus ideally suited for the growth of ultra-thin layers and atomically abrupt interfaces needed in future nanoelectronic devices. While CVD and ALD have many aspects in common, precursors suitable for ALD generally need to be much more reactive than those used for CVD. Another challenge is to combine low steric demand with very high selectivity of the surface reactions. 

Although many areas of nanotechnology do not directly deal with colloidal dispersions (such as nanoelectronic devices [952]) other areas do, such as the use of colloidal ink dispersions in robocasting to build near-nanometre scale three-dimensional structures. The possible use of nanoemulsions for intravenous delivery and in medical diagnostics has already been mentioned in Sections 14.4 and 14.5. Some other application areas include ... 

Recently, a profound interest in studies of properties of granulated metals, structures constituted by metallic nanoparticles, has been aroused. Problems associated with the application of these structures in the development of new nanoelectronic devices [1], devices for ultrahigh-density magnetic recording [2], new functional coatings [3], and high-efficiency solid-state catalysts [4] are widely discussed in the literature. This chapter is concerned with catalytic properties of metallic nanostructures. 

In the above two independent studies, the feasibility of CPMV as a nanobuilding block for chemical conjugation with redox-active compounds was demonstrated. The resulting robust, and monodisperse particles could serve as a multielectron reservoir that might lead to the development of nanoscale electron transfer mediators in redox catalysis, molecular recognition, and amperometric biosensors and to nanoelectronic devices such as molecular batteries or capacitors. 

The creation of new nanoelectronic devices is not possible without using of elements with anisotropic conductivity. One of the ways to solve the problem is considered here. All calculations are performed in framework of semi empirical PM3-method [1-2],... 

Nanomaterials with special morphology are attracting intense interest due to their remarkable optical, electrical and mechanical properties. Their potential uses ranging from microscopic probe to nanoelectronic devices. Therefore, current attention has focused on development of convenient approaches for preparing nanoscale structures with controlled shapes and sizes. 

MEM devices, thin films, (fullerenes, nanotubes, nanofibers, integrated circuits) dendritic polymers, nanoparticles, inorganic-organic nanocomposites nanoelectronic devices)... 

Dielectric breakdown in nanosize gate stack of state-of-the-art Si nanoelectronic devices has been one of the key reliability concerns. We present the recent development in using physical analysis techniques to decode the nature of the breakdown path or more commonly called as percolation path in ultrathin SiON and HfOi-based gate materials. 

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