Self Organized Organic Semiconductors

This book focuses on the exciting topic on self-organized organic semiconductors – from materials to device applications. It offers up-to-date and accessible coverage of self-organized semiconductors for organic chemistry, polymer science, liquid crystals, materials science, material engineering, electrical engineering, chemical engineering, optics, optic-electronics, nanotechnology and semiconductors. Chapters cover chemistry, physics, processing, and characterization. The applications include photovoltaics, light-emitting diodes (LEDs), and transistors.

This book focuses on the exciting topic on self-organized organic semiconductors – from materials to device applications. It offers up-to-date and accessible coverage of self-organized semiconductors for organic chemistry, polymer science, liquid crystals, materials science, material engineering, electrical engineering, chemical engineering, optics, optic-electronics, nanotechnology and semiconductors. Chapters cover chemistry, physics, processing, and characterization. The applications include photovoltaics, light-emitting diodes (LEDs), and transistors.

This thesis details the significant progress made in improving the performance of organic transistors and the network conductivity of carbon nanotubes. The first section investigates organic semiconductor nucleation and growth on the most common dielectric surface used to fabricate organic thin film transistors. The nucleation and growth of the semiconductor was determined to be a critical factor affecting the device performance. Excellent dielectric modification layers, which promote desirable semiconductor growth leading to high conductivity were identified, and a technologically relevant deposition technique was developed to fabricate high quality dielectric modification layers over large areas. This may represent an important step towards the realization of large area organic circuity. In the final section, lessons learned from studying organic semiconductor nucleation and growth were utilized to improve the conductivity of carbon nanotube networks. Selective nucleation of materials at the junctions between nanotubes in the network significantly decreased the network's sheet resistance. The resulting networks may be promising candidates for transparent electrodes with a variety of optoelectronic applications.

This thesis targets molecular or organic spintronics and more particularly the spin polarization tailoring opportunities that arise from the ferromagnetic metal/molecule hybridization at interfaces: the new concept of spinterface. Molecular or organic spintronics is an emerging research field at the frontier between organic chemistry and spintronics. The manuscript is divided into three parts, the first of which introduces the basic concepts of spintronics and advantages that molecules can bring to this field. The state of the art on organic and molecular spintronics is also presented, with a special emphasis on the physics and experimental evidence for spinterfaces. The book’s second and third parts are dedicated to the two main experimental topics investigated in the thesis: Self-Assembled Monolayers (SAMs) and Organic Semiconductors (OSCs). The study of SAMs-based magnetic tunnel nanojunctions reveals the potential to modulate the properties of such devices “at will,” since each part of the molecule can be tuned independently like a “LEGO” building block. The study of Alq3-based spin valves reveals magnetoresistance effects at room temperature and is aimed at understanding the respective roles played by the two interfaces. Through the development of these systems, we demonstrate their potential for spintronics and provide a solid foundation for spin polarization engineering at the molecular level.

This book focuses on the exciting topic of nanoscience with liquid crystals: from self-organized nanostructures to applications. The elegant self-organized liquid crystalline nanostructures, the synergetic characteristics of liquid crystals and nanoparticles, liquid crystalline nanomaterials, synthesis of nanomaterials using liquid crystals as templates, nanoconfinement and nanoparticles of liquid crystals are covered and discussed, and the prospect of fabricating functional materials is highlighted. Contributions, collecting the scattered literature of the field from leading and active players, are compiled to make the book a reference book. Readers will find the book useful and of benefit both as summaries for works in this field and as tutorials and explanations of concepts for those just entering the field. Additionally, the book helps to stimulate future developments.

The first advanced textbook to provide a useful introduction in a brief, coherent and comprehensive way, with a focus on the fundamentals. After having read this book, students will be prepared to understand any of the many multi-authored books available in this field that discuss a particular aspect in more detail, and should also benefit from any of the textbooks in photochemistry or spectroscopy that concentrate on a particular mechanism. Based on a successful and well-proven lecture course given by one of the authors for many years, the book is clearly structured into four sections: electronic structure of organic semiconductors, charged and excited states in organic semiconductors, electronic and optical properties of organic semiconductors, and fundamentals of organic semiconductor devices.

Edited and written by the leading researchers and engineers from such companies as Philips, 3M, Xerox, Infineon, PlasticLogic, Eastman Kodak, Dupont, AIXTRON, and Hueck Folien, this book presents unrivalled and undiluted expertise from those who know best how to assess the risks, opportunities and where this technology is really heading. As such, this practical approach complements the more scientific and fundamentals-oriented literature on the market by providing readers with a first-hand insight into industrial activities to commercialize organic electronics. Following an introduction to the topic, including the history, motivation, benefits and potentials, it reviews recent advances and covers all three important facets of organic electronics: the chemical compounds and materials, manufacturing techniques, and the resulting devices together with their current applications.