Opto-electronic devices

The science and technology of conducting polymers are inherently interdisciplinary they fall at the intersection of three established disciplines chemistry, physics and engineering hence the name for this volume. These macromolccular materials are synthesized by the methods of organic chemistry. Their electronic structure and electronic properties fall within the domain of condensed matter physics. Efficient processing of conjugated polymer materials into useful forms and the fabrication of electronic and opto-electronic devices require input from engineering i. e. materials science (more specifically, polymer science) and device physics. 

Semiconductor lasers have undergone a considerable metamorphosis during the past 30 years. They have grown and developed into a whole range of sophisticated opto-electronic devices. It is beyond the scope of this section to give a detailed description of the different semiconductor lasers, but we shall summarize the basic principles of this type of laser. 

We can already deduce that, due to the characteristics of the active medium, compact and miniaturized devices are attainable for semiconductor lasers. This fact, together with the possibility of custom-designed systems, constitutes a real advantage from the viewpoint of integrated opto-electronic devices. In the field of spectroscopy, they are commonly used as pumping sources for other types of solid state lasers, as will be seen later. 

The metal-ligand fragment L M, the number of carbon atoms x, and the substituents at the terminal sp -carbon may vary considerably and, correspondingly, the properties and reactivities. The early members of the series of cumulenylidene complexes (x=l, 2, 3 carbene, vinylidene and allenylidene complexes) have established themselves as invaluable building blocks in stoichiometric synthesis and as highly potent catalyst precursors. The higher members might potentially be very useful candidates for application as one-dimensional wires and in opto-electronic devices. 

One of the most promising bottom-up approaches in nanoelectronics is to assemble 7i-conjugated molecules to build nano-sized electronic and opto-electronic devices in the 5-100 nm length scale. This field of research, called supramolecular electronics, bridges the gap between molecular electronics and bulk plastic electronics. In this contest, the design and preparation of nanowires are of considerable interest for the development of nano-electronic devices such as nanosized transistors, sensors, logic gates, LEDs, and photovoltaic devices. 

Tacticity is required for the synthesis of crystalline thin polysilane films used for optical and semiconductor devices. Modern synthetic routes allow control over the conformation and tacticity of polysilane molecules used as precursors for thin layers of photoresists, photoconductors and nonlinear optical phases in complex semiconductor and (opto)electronic devices. These properties can be exploited only if the synthesis method ensures a minimal level of contamination, especially with oxygen and metals, and special care is taken to limit electronic-grade polysilanes to a level of contamination on the order of a few ppm in the case of oxygen and in the ppb range for metals. The reactivity of polysilane toward oxygen has forced placing the devices in a helium environment during measurement procedures.36... 

Applications of conjugated polymers-NCs hybrids in various (opto-)electronic devices and sensors require a deeper understanding of the relationship between their chemical and photophysical properties and their structure at different levels from the molecular to the bulk material. This requires the use of complementary methods... 

Holder E Tessler N Rogach AL, Hybrid nanocomposite materials with organic and inorganic components for opto-electronic devices, J. Mater. Chem., 2008,18, 1064-1078. 

In the photophysical aspect, many platinum acetylides exhibit a luminescent property. The photo- and electrochemical research for such species combines with the structural chemistry to pave a path toward the exploration of molecular opto-electronic devices, and is described in Section 3.3. 

Eichou, D., Structural order in conjugated ohgothiophenes and its implications on opto-electronic devices, J. Mater. Ghent., 10, 571, 2000. 

In developing a material for use in device applications, it has been found that deep energy levels, in the forbidden energy gap, play an important role. Deep levels can act as carrier recombination or trapping centres and affect the performance of electronic and opto-electronic devices. Deep levels have been a subject of investigation for over thirty years and several excellent reviews are available Grimmeiss [1], Neumar and Kosai [2], Milnes [3] and on the capacitance measurement techniques Lang [4],... 

Embedding SiGe and Ge quantum structures into the Si host crystal opens up new paths for the integration of ultra fast electronic and opto-electronic devices into the mature Si microelectronics. In this paper some of these paths are discussed and the challenging problems of materials research are addressed. Special emphasis is put on the Dot-FET concept and on the possibility of light emission from Si/SiOe quantum structures. 

There are some excellent review articles on different aspects of mesostructured materials, such as synthesis, properties, and applications. " Extensive research effort has been devoted to the exploitation of new phases (lamellar, cubic, hexagonal structures), expansion of the pore sizes (about 2-50 nm are accessible), and variable framework compositions (from pure silica, through mixed metal oxides to purely metal oxide-based frameworks, and inorganic-organic hybrid mesostructures). Another research focus is on the formation of mesostructured materials in other morphologies than powders, e.g. monolithic materials and films, which are required for a variety of applications including, but not limited to, sensors (based on piezoelectric mass balances or surface acoustic wave devices), catalyst supports, (size- and shape-selective) filtration membranes or (opto)electronic devices. The current article is focused... 

Also, fluorine-carbon composites were investigated as functional coating materials in a wide variety of applications coating materials for construction under low temperature environments [139], protective coating for computer hard disks [140], automotive components [141], semiconductor in opto-electronic devices [142, 143], and biomedical implants [144]. Those applications follow outstanding physicochemical, electrical and mechanical properties of these materials, (i.e., hardness, friction, water repellency, chemical... 

Pearcy, M. J., Gill, J. M., Hindle, J., and Johnson, G. R. (1987), Measurement of Human Back Movements in Three Dimensions by Opto-Electronic Devices, Clin. Biomech, Vol. 2, pp. 199-204. 

When a polymer solution is allowed to evaporate from a surface, dewetting instabilities can arise, producing modulated patterns like spinodal structures (68). Section IV addresses the applicability of these interesting phenomena to making opto-electronical devices. 

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