Transistors molecular electronic materials

Organic Field Effect Transistors/Molecular Electronics. Organic field effect transistors (OFETS) and molecular electronics are two areas of intensive research for both academic and industrial institutions (346). The extensive research on these devices stems from their ability to be processed at low temperatures and from their compatibility with plastic substrates. Several applications of OFETs have been proposed, including smart cards (347), active matrix displays (348), and logic circuits (349). Both polymeric and oligomeric materials have been studied for use in OFETs because the properties can be tailored to vary the HOMO-LUMO gap physical characteristics such as mechanical flexibility and processability are also advantageous (350). 

Electronic properties semiconductor and metal conductivity, magneto-resistance, emission of electrons, electronic devices of the molecular size, information recording, diodes, field transistors, cold cathodes, materials for displays, quantum wires and dots, cathodes for X-ray radiation, electric probes, etc. 

Thus, the ideas behind the bottom-up approach are as simple as powerful. The general aim lies in the design of novel materials employable for molecular-scale electronics, such as molecular transistors, molecular photovoltaic applications, molecular display technology, etc. Hereby, the functions are carefully adjusted by synthetic tools to build up a certain chemical structure. In this context, we need to address the key steps/challenges in such a work-flow. With this in hands the impetus of this thesis should be illustrated. 

Memory devices (electrical, optical) Molecular electronics Nonlinear optics Packaging materials pH modulator Polymer/solid electrolytes Semiconducting devices p-n junctions, pho-tovoltaics, Schottky diodes, light-emitting diodes, transistors, etc. 

The field of molecular electronics may be considered to encompass much more than molecular electronic devices. In its broadest context, molecular electronics may be regarded as simply the application of molecules, primarily organic molecules, to electronics. This definition would include such areas as liquid crystalline materials, piezoelectric materials such as poly(vinylidine fluoride), chemically sensitive field-eflFect transistors (CHEMFET), and the whole range of electroactive polymers. These applications are beyond the scope of this book and are covered in other reviews 34, 33). However, given the basic tenet of molecular electronics, namely, the ability to engineer and assemble molecular structures into a useful device, the broader definition raises the question of whether organic molecules can be specifically assembled or engineered for unique applications in electronics. 

Abstract Recent advances in fluorene-based conjugated oligomers are surveyed, including molecular design, material synthesis and characterization, and potential application to organic photonics and electronics, such as light-emitting diodes, solid-state lasers, field effect transistors, and solar cells. 

The realization of functional nanosized materials has been achieved thanks to the development of innovative methods for the synthesis and the characterization of physical properties required for potential technological applications. So far, several domains have benefited from properties offered by nanostructured systems. Examples are the superplasticity in mechanics, the efficiency of luminescence in optics, the gain in memory storage in magnetism, the tendency to develop molecular transistor in electronics and realization of therapeutic structures based on functional nanoparticles in medicine. AH these facts underline the importance of nanomaterials and their usefulness for new technologies. 

This chapter and the next describe chemical bonding. First, we explore the interactions among electrons and nuclei that account for bond formation. Then we show how atoms are connected together in simple molecules such as water (H2 O). We show how these connections lead to a number of characteristic molecular geometries, hi Chapter fO, we discuss more elaborate aspects of bonding that account for the properties of materials as diverse as deoxyribonucleic acid (DNA) and transistors. 

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