Characterization and Optimization of Growth and Electronic Structure of Organic Thin Films for Applications in Organic Electronics PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Characterization and Optimization of Growth and Electronic Structure of Organic Thin Films for Applications in Organic Electronics PDF full book. Access full book title Characterization and Optimization of Growth and Electronic Structure of Organic Thin Films for Applications in Organic Electronics by Daniel Käfer. Download full books in PDF and EPUB format.
Author: Daniel Käfer
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Daniel Käfer
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Karol Cieslik
Publisher: Karol Cieslik
ISBN:
Category : Science
Languages : en
Pages : 80
Get Book Here
Book Description
Organic thin film devices’ performance depends on their properties, such as the crystallinity of the active layer and the specific arrangement of molecules in it. The morphology of molecular structures can be studied using imaging techniques (such as atomic force microscopy AFM, scanning tunneling microscopy STM, and scanning electron microscopy SEM),but to gain a more complete understanding of their nature, temperature programmed desorption (TPD) may be used. During a TPD experiment, the temperature of the adsorbate-adsorbent system is increased linearly while simultaneously the number of desorbing molecules is measured. The resulting TPD spectrum may be used to determine the type of structure (monolayer, multilayer) and the desorption energy associated with it. Furthermore, the thermal stability of observed structures, as determined by the temperatures at which desorption occurs, is evident from the TPD spectra. Thus, TPD measurements may lead to a better understanding of the growth and characteristics of molecular structures which may be of use for potential applications in organic electronics. The first aim of this thesis was the assembly and calibration of the TPD system. The optimal parameters of the mass spectrometer (ionizer’s emission current and electron energy) were determined. Moreover, the linear heating of the samples using direct resistive heating was established. The optimal mass-to-charge ratio for para-hexaphenyl (6P) was determined based on the mass spectrum of 6P. The final test of the TPD system was a comparison of the measured TPD spectrum of 6P film grown on mica(001) with the one published in the literature. The second aim was the measurement of spectra of 6P films on ion-beam modified (110) surfaces of TiO2. Two substrates of different topographies (determined by STM) were studied: one with deep ripples (height modulation of 2.6nm) and one with shallow ripples (height modulation of 0.76nm).In the case of the deep-rippled sample, the effect of molecular film coverage, and the desorption from the sample holder on the measured spectra was investigated. In contrast, the shallow-rippled sample was only studied in the context of the effect of desorption from the sample holder on the spectra. The morphology of 1.91nm thin film of 6P on the deep-rippled sample was studied using SEM, while the morphology of a 0.57nm thin 6P film on shallow-rippled TiO2(110) was determined using STM and AFM. Additionally, the desorption of 6P powder from an effusion cell was studied for comparison of the bulk and thin-film desorption parameters. The optimal parameters for the spectrometer’s ionizer were determined to be: emission current of 700μA, electron energy of 37eV, and use of two filaments. The chosen mass-to-charge ratio was 229.35, e.i. 6P with 2+ charge. The TPD spectrum of 1.91nm of 6P on mica(001) contained a multilayer peak at temperature 222℃ which was in agreement with published data. Due to desorption from the sample holder, all spectra in the TPD experiments showed additional peaks and an increase in background intensity. This effect was almost completely eliminated by covering parts of the holder with tantalum sheets during the molecule deposition process. The TPD spectra for 6P grown on both samples contained two peaks: one which began at approximately 180℃ and ended at different temperatures depending on coverage and another which began at 300℃(the complete spectrum for the deep-rippled sample was not measured, but the peak ended at 550℃ for the shallow-ripples sample). The first peak is due to multilayered molecular structures, which, based on morphologies of the samples, can be identified as originating from standing-molecule islands and laying-molecule nanoneedles in the case of deep-rippled, and laying-molecule nanoneedles for shallow-rippled TiO2(110). The second peak is probably due to a monolayer of 6P molecules laying directly on the TiO2 surface (such a layer was observed for the shallow-rippled sample).
Author: Abraham Ulman
Publisher: Butterworth-Heinemann
ISBN:
Category : Science
Languages : en
Pages : 302
Get Book Here
Book Description
Characterization of Organic Thin Films will help materials scientists, physicists, chemists, and biologists develop a fundamental understanding of structure-properties relationships which in turn makes possible molecular engineering of advanced materials and opens new opportunities in molecular manufacturing.
Author: Mahmoud Vahidi
Publisher:
ISBN:
Category : Microelectronics
Languages : en
Pages : 81
Get Book Here
Book Description
I studied the properties of novel Co2FeAl0.5Si0.5 (CFAS), ZnGeAs2, and FeS2 (pyrite) thin films for microelectronic applications ranging from spintronic to photovoltaic. CFAS is a half metal with theoretical spin polarization of 100%. I investigated its potential as a spin injector, for spintronic applications, by studying the critical steps involved in the injection of spin polarized electron populations from tunnel junctions containing CFAS electrodes. Epitaxial CFAS thin films with L21 structure and saturation magnetizations of over 1200 emu/cm3 were produced by optimization of the sputtering growth conditions. Point contact Andreev reflection measurements show that the spin polarization at the CFAS electrode surface exceeds 70%. Analyses of the electrical properties of tunnel junctions with a superconducting Pb counter-electrode indicate that transport through native Al oxide barriers is mostly from direct tunneling, while that through the native CFAS oxide barriers is not. ZnGeAs2 is a semiconductor comprised of only inexpensive and earth-abundant elements. The electronic structure and defect properties are similar in many ways to GaAs. Thus, in theory, efficient solar cells could be made with ZnGeAs2 if similar quality material to that of GaAs could be produced. To understand the thermochemistry and determine the rate limiting steps of ZnGeAs2 thin-film synthesis, the (a) thermal decomposition rate and (b) elemental composition and deposition rate of films were measured. It is concluded that the ZnGeAs2 thin film synthesis is a metastable process with an activation energy of 1.08±0.05 eV for the kinetically-limited decomposition rate and an evaporation coefficient of ~10-3. The thermochemical analysis presented here can be used to predict optimal conditions of ZnGeAs2 physical vapor deposition and thermal processing. Pyrite (FeS2) is another semiconductor that has tremendous potential for use in photovoltaic applications if high quality materials could be made. Here, I present the layer-by-layer growth of single-phase pyrite thin-films on heated substrates using sequential evaporation of Fe under high-vacuum followed by sulfidation at S pressures between 1 mTorr and 1 Torr. High-resolution transmission electron microscopy reveals high-quality, defect-free pyrite grains were produces by this method. It is demonstrated that epitaxial pyrite layer was produced on natural pyrite substrates with this method.
Author: Sushil Kumar
Publisher: Springer Nature
ISBN: 9811561168
Category : Technology & Engineering
Languages : en
Pages : 721
Get Book Here
Book Description
This volume comprises the expert contributions from the invited speakers at the 17th International Conference on Thin Films (ICTF 2017), held at CSIR-NPL, New Delhi, India. Thin film research has become increasingly important over the last few decades owing to the applications in latest technologies and devices. The book focuses on current advances in thin film deposition processes and characterization including thin film measurements. The chapters cover different types of thin films like metal, dielectric, organic and inorganic, and their diverse applications across transistors, resistors, capacitors, memory elements for computers, optical filters and mirrors, sensors, solar cells, LED's, transparent conducting coatings for liquid crystal display, printed circuit board, and automobile headlamp covers. This book can be a useful reference for students, researchers as well as industry professionals by providing an up-to-date knowledge on thin films and coatings.
Author: Gertjan Koster
Publisher: Elsevier
ISBN: 0857094955
Category : Technology & Engineering
Languages : en
Pages : 295
Get Book Here
Book Description
Advanced techniques for characterizing thin film growth in situ help to develop improved understanding and faster diagnosis of issues with the process. In situ characterization of thin film growth reviews current and developing techniques for characterizing the growth of thin films, covering an important gap in research. Part one covers electron diffraction techniques for in situ study of thin film growth, including chapters on topics such as reflection high-energy electron diffraction (RHEED) and inelastic scattering techniques. Part two focuses on photoemission techniques, with chapters covering ultraviolet photoemission spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS) and in situ spectroscopic ellipsometry for characterization of thin film growth. Finally, part three discusses alternative in situ characterization techniques. Chapters focus on topics such as ion beam surface characterization, real time in situ surface monitoring of thin film growth, deposition vapour monitoring and the use of surface x-ray diffraction for studying epitaxial film growth. With its distinguished editors and international team of contributors, In situ characterization of thin film growth is a standard reference for materials scientists and engineers in the electronics and photonics industries, as well as all those with an academic research interest in this area. Chapters review electron diffraction techniques, including the methodology for observations and measurements Discusses the principles and applications of photoemission techniques Examines alternative in situ characterisation techniques
Author: Klaus Wetzig
Publisher: John Wiley & Sons
ISBN: 3527606475
Category : Science
Languages : en
Pages : 388
Get Book Here
Book Description
This up-to-date handbook covers the main topics of preparation, characterization and properties of complex metal-based layer systems. The authors -- an outstanding group of researchers -- discuss advanced methods for structure, chemical and electronic state characterization with reference to the properties of thin functional layers, such as metallization and barrier layers for microelectronics, magnetoresistive layers for GMR and TMR, sensor and resistance layers. As such, the book addresses materials specialists in industry, especially in microelectronics, as well as scientists, and can also be recommended for advanced studies in materials science, analytics, surface and solid state science.
Author: Fatma Sarf
Publisher: BoD – Books on Demand
ISBN: 1837691355
Category : Technology & Engineering
Languages : en
Pages : 178
Get Book Here
Book Description
This book focuses on the growth of nanomaterials as thin films. It covers the recent development of thin films using different techniques, such as electrodeposition. It also discusses the widespread use of electrochemical and magnetic applications. This book brings together multidisciplinary chapters written by leading specialists in the field.
Author: Yu Song
Publisher: John Wiley & Sons
ISBN: 3527344993
Category : Technology & Engineering
Languages : en
Pages : 768
Get Book Here
Book Description
Learn more about foundational and advanced topics in polymer thin films and coatings besides species with this powerful two-volume resource The two-volume Inorganic and Organic Thin Films: Fundamentals, Fabrication, and Applications delivers a foundational resource for current researchers and commercial users involved in the design and fabrication of thin films. The book offers newcomers to the field a thorough description of new design theory, fabrication methods, and applications of advanced thin films. Readers will discover the physics and chemistry underlying the manufacture of new thin films and coatings in this leading new resource that promises to become a handbook for future applications of the technology. This one-stop reference brings together all important aspects of inorganic and polymeric thin films and coatings, including construction, assembly, deposition, functionality, patterning, and characterization. Explorations of their applications in industries as diverse as information technology, new energy, biomedical engineering, aerospace, and oceanographic engineering round out this fulsome exploration of one of the most exciting and rapidly developing areas of scientific and industrial research today. Readers will also learn from: A comprehensive introduction to the progress of thin films and coatings as well as fundamentals in functional thin films and coatings An exploration of multi-layered magnetic thin films for electron transport control and signal sensing, including giant magnetoresistance, colossal magnetoresistance, tunneling magnetoresistance, and the quantum anomalous Holzer effect An in time summary of high-quality magneto-optics, nanophotonics, spin waves and spintronics using bismuth-substituted iron garnet thin films as examples A thorough discussion of template-assisted fabrication of nanostructure thin films for ultrasensitive detection of chemicals and biomolecules A treatment of biomass derived functional films and coatings Perfect for materials scientists and inorganic chemists, Inorganic and Organic Thin Films will also earn a place in the libraries of solid state physicists and physical chemists working in private industry, as well as polymer and surface chemists who seek to improve their understanding of thin films and coatings.
Author: Horst-Günter Rubahn
Publisher: Springer Science & Business Media
ISBN: 3540959300
Category : Technology & Engineering
Languages : en
Pages : 208
Get Book Here
Book Description
Organic semiconductors are a central topic of advanced materials research. The book is aiming at bridging the gap between the development and production of devices and basic research on thin film characterisation using cutting-edge techniques in surface and interface science. Topics involve organic molecular-based sensors; interfaces in organic diodes and transistors; mobility in organic field effect transistors and space charge problems; integration of optoelectronic nanostructures; nonlinear optical properties of organic nanostructures; the wetting layer problem; how to get from functionalized molecules to nanoaggregates; optical, electrical and mechanical properties of organic nanofibers as well; as near field investigations of organic thin films.
