Physics Commons^™

Wrinkling Of Floating Thin Polymer Films, Jiangshui Huang

Doctoral Dissertations 1896 - February 2014

This thesis presents an extensive study of wrinkling of thin polystyrene films, tens of nanometers in thickness, floating on the surface of water or water modified with surfactant.

First, we study the wrinkling of floating thin polystyrene films under a capillary force exerted by a drop of water placed on its surface. The wrinkling pattern is characterized by the number and length of wrinkles. A metrology for measuring the elasticity and thickness of ultrathin films is constructed by combining the scaling relations that are developed for the length of the wrinkles with those for the number of wrinkles. This metrology …

A Solution-Based Approach To The Fabrication Of Novel Chalcogenide Glass Materials And Structures, Nathan Carlie

All Dissertations

Chalcogenide glasses (ChGs) are well known for their large optical nonlinearities and high infrared transparency, and are candidate materials for next-generation thin film-based planar infrared (IR) optical applications. They are also known, however, to possess low thermal and mechanical stability as compared to oxide glasses. Traditional physical vapor deposition (PVD) methods used for the deposition of these materials as thin films often suffer from low deposition rates, deviation from stoichiometry, and cannot coat over complex surfaces. In order to retain the attractive optical properties of ChGs while enabling new fabrication routes and hybrid and composite material systems, we have developed …

Measurement Of Thermoelectric Properties Of Amorphous Silicon Based Thin Films, Rubina Sultan

Electronic Theses and Dissertations

It is important to understand thermal transport behavior in materials for technological and fundamental physics applications. Many efforts have been made in the past for explaining thermal conduction in solids. It has been observed that thermal transport properties may change with reducing size of the sample, especially as sample size approaches the nanoscale regime. The deviation in these properties, mainly in thermal conductivity, may change the choice of the material for different applications such as thermoelectricity. Thermoelectric materials are a possible source of sustainable energy and can play an important role in the fight against the present energy crisis. Recently, …

Spectroscopic Analysis Of Tungsten Oxide Thin Films For Sensor Applications, Jose Luis Enriquez Carrejo

Open Access Theses & Dissertations

The objective of this study is targeted toward improving the quality of pure tungsten oxide (WO3) for application to the detection of poisoning gases, especially of H2S. While pure WO3 is a recognized candidate for gas sensing, its characteristics are strongly dependent on the conditions and methods used in its deposition.

Samples of WO3 thin films analyzed in this work were grown on silicon and sapphire substrates using RF magnetron sputtering at a number of different substrate temperatures and Ar:O2 pressure ratios. The properties of the samples were investigated spectroscopically with the goal of determining how variations in the above …

Structure And Optical Properties Of Cuals_2 Thin Films Prepared Via Chemical Bath Deposition, Tariq Alwan, Mushtak Jabbar

Turkish Journal of Physics

CuAlS_2 thin films of thicknesses 118 \pm 5 nm were deposited on glass substrates using chemical bath deposition technique. The details of the preparation method are well described. The method is relatively simple and is easily controlled and sufficient to produce large area and good adherence to the substrate films. Effect of annealing temperature T_a on the structure, and optical properties of CuAlS_2 films were investigated. The structures of the films were studied by X-ray diffraction and FTIR spectrophotometer. The optical properties of the films were ascertained by UV-VIS spectrophotometer (wavelengths ranging between 300 and 900 nm). The optical transmittance …

Thin Film Group Ii-Vi Solar Cells Based On Band-Offsets, James Keith Walton

Dissertations and Theses

The amount of traditional energy sources are finite and the ecological impact of continuing to produce energy using fossil fuels will only exacerbate the carbon footprint. It is for these reasons that photovoltaic modules are becoming a larger and more necessary part the world's electricity production paradigm.

Photovoltaic (PV) semiconductor modules are grouped into three categories. 'First generation' monocrystalline and polycrystalline silicon modules that consist of p-n junctions created via the addition of impurities known as dopants. Almost 85% of solar cells produced at this time are 'first generation' and it is the high production costs of silicon PV modules …