Subject nanofabrication

Electroless deposition as we know it today has had many applications, e.g., in corrosion prevention [5-8], and electronics [9]. Although it yields a limited number of metals and alloys compared to electrodeposition, materials with unique properties, such as Ni-P (corrosion resistance) and Co-P (magnetic properties), are readily obtained by electroless deposition. It is in principle easier to obtain coatings of uniform thickness and composition using the electroless process, since one does not have the current density uniformity problem of electrodeposition. However, as we shall see, the practitioner of electroless deposition needs to be aware of the actions of solution additives and dissolved O2 gas on deposition kinetics, which affect deposit thickness and composition uniformity. Nevertheless, electroless deposition is experiencing increased interest in microelectronics, in part due to the need to replace expensive vacuum metallization methods with less expensive and selective deposition methods. The need to find creative deposition methods in the emerging field of nanofabrication is generating much interest in electroless deposition, at the present time more so as a useful process however, than as a subject of serious research. 

Dimensions between the atomic/molecular and the bulk macroscopic scales are sometimes called mesoscopic. Because the mesoscopic scale corresponds roughly to the electron free path, unusual phenomena such as quantum effects can be observed, some of which could be used in the development of single-electron devices or quantum computers. Top-down-type nanofabrication techniques are now capable of producing structures in this size range, and research on this subject has received significant attention, especially in the held of semiconductor science and technology. 

Microphase separation (MPS) leading to regular patterns at nanometer levels formed by block copolymers in thin films has recently been a subject of intensive study. Such nanostructures allow for fabrication of even smaller feature sizes than those obtained by the conventional photolithography process, and have potentials for future nanofabrications (Lazzari et al., 2006). Attempts to create active and photocontrollable MPS systems are a fascinating challenge. 

The adsorption of surfactants on solid surfaces has been the subject of numerous studies. This phenomenon has widespread technological applications in wetting, adhesion, nanofabrication, and cleaning and degreasing of metal surfaces. The adsorbed... 

One of the most successful examples is chromatographic separation of SWNTs wrapped with DNA [136,137,139,140]. Quite recently, (6,4), (9,1) and (6,5) SWNTs were obtained in almost pure form by sorting of CoMoCAT SWNTs wrapped with DNA with conventional ion-exchange chromatography [33]. The SWNTs/DNA solution was subjected to a variety of optical analyses such as circular dichroism, photoluminescence and absorption spectroscopies [141-143] as well as investigation of their photo- and electrochem-icalbehaviors [144,145]. The strong interaction between SWNT and DNA was simulated theoretically by molecular dynamics [146] and ab initio calculations [147], and used for nanofabrication of SWNTs [148,149]. 

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