Computer, miniaturization

Developments in electroanalytical chemistry are driven by technical advances in electronics, computers, and materials. Present scientific capabilities available in a research laboratory will be applicable for field measurements with the advent of smaller, less expensive, more powerful computers. Miniaturization of electrochemical cells, which can improve perfonnance, especially response time, can be implemented most effectively in the context of miniaturization of control circuitry. Concomitant low cost could make disposable systems a practical reality. Sophisticated data analysis and data handling techniques can, with better facilities for computation, be handled in real time. 

IBM scientists presented this achievement at the 2001 National Meeting of the American Chemical Society in Chicago. It was the second major research development last year by IBM scientists using carbon nanotubes to make tiny electronic devices. Carbon nanotubes are the top candidate to replace silicon when current chip features just cannot be made any smaller a physical barrier expected to occur in about 10 to 15 years. Beyond this silicon nanotube electronics may then lead to unimagined progress in computing miniaturization and power. 

Other examples of electrical applications for LCP include lens holders for optical pick-up parts in CD-ROM, DVD, transformers for miniature modems in laptop computers, miniature relays, coil bobbins and sockets for halogen light fittings. 

Most spectroscopical analysis is a data intensive process. A single sample scan across a wavelength region of interest can produce a two- or three-dimensional set of data containing 2000 or 3000 data points. A few dozen scans of that sample can yield a data set that was quite cumbersome to handle just a few years ago. It is essential to acknowledge that all forms of spectroscopy and spectrometry have been greatly enhanced by the development of personal computers. When Fourier transform IR spectrometers were first commercialized they filled a room. Today they can fit into a suitcase and be operated in the heart of the wilderness. To be sure, there are trade-offs to be made in instrument performance within these extremes, but computer miniaturization has played a significant part in this development. 

Sohd tantalum capacitors have a high volumetric capacitance which makes them attractive for use in miniaturized electronic systems like cellular telephones, hand-held video cameras, and personal computers. The insensitivity of their capacitance to temperature and their abiUty to operate at temperature extremes explains why these devices are used in such harsh environments as automobile engine compartments. Sohd tantalum capacitors are extremely rehable and, therefore, are often the capacitor of choice in critical appHcations like spacecraft electronics, pacemakers, and safety equipment. 

The pursuit of further miniaturization of electronic circuits has made submicrometer resolution Hthography a cmcial element in future computer engineering. LB films have long been considered potential candidates for resist appHcations, because conventional spin-coated photoresist materials have large pinhole densities and variations of thickness. In contrast, LB films are two-dimensional, layered, crystalline soHds that provide high control of film thickness and are impermeable to plasma down to a thickness of 40 nm (46). The electron beam polymerization of CO-tricosenoic acid monolayers has been mentioned. Another monomeric amphiphile used in an attempt to develop electron-beam-resist materials is a-octadecylacryUc acid (8). 

FIGURE 15.29 These micrographs show that a block < opolymcr on its own > rystallizes in a chaotic pattern a) nanoscale techniques wcr used to produce the self-assi mbled parallel array o the same copolymer in (b) Such n gular arrays could be used to make ultra-high density memory chips to store information in miniature computers... 

The newest addition to the forms of elemental carbon is the nanotube. A carbon nanotube is a long cylinder of carbon atoms, connected together in much the same way as in a fullerene. Both the diameter and the length of carbon nano-tubes can vary. Properties of nanotubes, such as their ability to conduct electrical charge, change dramatically with the dimensions of the tube. Carbon nanotubes are under intensive study. For example, a carbon nanotube laid down on a silicon chip forms a molecular transistor. Such devices may eventually lead to further miniaturization of the chips that are at the heart of modem computers. 

With the introduction of modern electronics, inexpensive computers, and new materials there is a resurgence of voltammetric techniques in various branches of science as evident in hundreds of new publications. Now, voltammetry can be performed with a nano-electrode for the detection of single molecular events [1], similar electrodes can be used to monitor the activity of neurotransmitter in a single living cell in subnanoliter volume electrochemical cell [2], measurement of fast electron transfer kinetics, trace metal analysis, etc. Voltammetric sensors are now commonplace in gas sensors (home CO sensor), biomedical sensors (blood glucose meter), and detectors for liquid chromatography. Voltammetric sensors appear to be an ideal candidate for miniaturization and mass production. This is evident in the development of lab-on-chip... 

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