Nanotube/nanowire-based devices

There are more issues and complexity to be considered if various micro-electromechanical (MEMS)-type devices are included in the macroelectronics tool kit. As described previously, the materials and devices required for TFTs and circuits can provide adequate electromagnetic (visible and RF) sensitivity for many image-type applications. These materials may also provide satisfactory performance in pressure and strain sensors. Nanotube/nanowire-based devices look promising for various chem-bio sensors.85 However, there is little that is known about the ability to integrate printed microfluidic devices (and other such devices with moving parts) into a roll-to-roll-type process. 

Potentiometric biosensors based in both ISE and ISFET for water analysis have been widely developed in the last few years, with recent research leading to nanomaterial-based devices. New nanoparticle (NP)-based signal amplification and coding strategies for bioaffinity assays are in use, along with molecular carbon-nanotube (CNT) wires for achieving efficient electrical communication with redox-enzyme and nanowire-based label-free DNA sensors. ... 

For either conventional polycrystalline semiconductors or nanotubes and nanowires to be successful, the development of model and simulation tools that can be used for device and circuit design as well as for predictive engineering must be available. Since these devices are not necessarily based on single wires or single crystals, but rather on an ensemble of particles, the aggregate behavior must be considered. Initial efforts to provide the necessary physical understanding and device models using percolation theory have been reported.64,65... 

FETs are actually the basic building blocks of integrated circuits. To develop circuits using nanotubes, we first have to design nanotube-based transistors. Silicon nanowires represent one of the best characterized examples of semiconductor nanotubes with the structure, size, and electronic properties controlled reproducibly (Hu et al., 1999 Cui et al., 2001a). In particular, silicon nanowires can be prepared as single-crystal structures with controllable diameters as small as 2 to 3 nm (Cui et al., 2003 Wu, 2004). Both n- and p-type FET devices can be produced with well-defined and reproducible high-performance properties... 

PET foils were used by McAlpine et al. (2007) as the substrate onto which nanotubes were deposited (see Section 6.7.1). The device showed itself to be suitable for measuring NO at room temperature. ZnO nanowires were grown on Pl-based micro-hotplates by Zappa et al. (2012). Zn was sputtered onto the substrate through a shadow mask and then oxidized for 12 hours... 

Semiconducting one-dimensional (ID) nanolibers or nanowires are of interest for a wide variety of applications including interconnects, functional devices, and molecular sensors as well as for fundamental physics studies. Devices have been fabricated fi om semiconductor, and carbon nanotubes, and more recently from ICP nanofibers. It has been predicted that ICP nanofibers will have unique electrical, optical, and magnetic properties [134]. Several different methods for producing these ICP nanofibers have been developed with or without the aid of a template. The template-based methods involve synthesizing a tubular structure of the ICP within the pores of a support membrane, such as an alumina membrane [135] or a track-etched polycarbonate membrane [136]. However, more recent work has... 

The fact that carbon nanotubes can be made either semiconducting or metallic without any doping is unique among solid-state materials, and laboratories worldwide are making and testing carbon-based electronic devices. Carbon nanotubes are also being explored for their mechanical properties. The carbon-carbon bonded framework of the nanotubes means that the imperfections that might appear in a metal nanowire of similar dimensions are nearly absent. Experiments on individual carbon nanotubes... 

Conductive polymeric nanostructures can be prepared by using hard or soft templates or with template-free methods. The template method has been extensively used because of its simplicity, versatility and controllability. Some further features on this topic are reported in Section 1.3. A typical hard template material can be a thin porous film of aluminum oxide or polycarbonate and polymeric materials ean be deposited into the pores to form nanotubes or nanowires. The electrochemical template method enables a better control of the dimensions compared with the chemical methods. In addition, the nanostructures produced by the electrochemical method are in solid contact with a base electrode that is beneficial for further processing steps when building an electrochemical device. 

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