Nanocrystal nanoelectronics

The goal of materials research is really the reverse process, the bottom-up method. In this approach, it is hoped that perfect well-controlled nanoparticles, nanostrucmres, and nanocrystals can be synthesized, which may be compacted into macroscopic nanocrystalline samples, or assembled into superlattice arrays, which may, in mrn, be used in a variety of applications such as nanoelectronic or magnetic devices. Some scientists have even envisioned a time when so-called molecular assemblers will be able to mechanically position individual atoms or molecules, one at a time, in some predefined way (Drexler, 1986). The feasibility of such machines has been hotly debated but, regardless, such systems engineering goals are not really within the scope of this chapter. At present, methods for synthesizing metal and ceramic clusters and nanoparticles fall in one of two broad categories liquid phase techniques or vapor/aerosol methods. 

We have reviewed in this chapter the electronic structure and properties of semiconducting nanocrystals, materials that can be used in the field of nanoelectronics in the near future. Some of these materials already show very interesting properties that can be utilized to make devices and, therefore, it is necessary to have proper experimental and theoretical tools to probe and understand the electronic properties quantitatively. 

The research in nanoelectronic materials is driven by the need to tailor electronic and optical properties for specific components in nanotechnology. In this respect, semiconductor nanocrystals (NCs) surfacely passivated by organic molecules are candidates for possible practical applications. A success in usage of NC-organic composites depend on the understanding their optical and photophysical characteristics as well as their surface/interface properties and stability [1]. 

Ge M, Fang X, Rong J, Zhou C (2013) Review of porous silicon preparation and its application for lithium-ion battery anodes. Nanotechnology 24(422001) 1-10 Gelloz B (2010) Chapter 14 Silicon nanocrystals in porous silicon and their applications. In Pavesi L, Turan R (eds) Silicon nanocrystals. Wiley-VCH, Weinheim Golovan L, Timoshenko VY (2013) Nonlinear-optical properties of porous silicon nanostructures. J Nanoelectron Optoelectron 8(3) 223-239... 

Antolini et al. found that CdS nanocrystals could be obtained by regioselective thermal decomposition of metal alkanethiolates in a PS matrix by selective heating of a polymer foil filled with the cadmium-(bis)-thiolate precursor by means of focused laser beam irradiation. The nanocomposites were characterized by strong PL with an emission maximum at 535 nm, which confirms the presence of CdS nanocrystals. These materials can be use for preparation of nanoelectronic devices or conductive plastics [203]. 

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