We consider the dynamics of an elastic sheet lubricated by the flow of a thin layer of fluid that separates it from a rigid wall. By considering long wavelength deformations of the sheet, we derive an evolution equation for its motion, accounting for the effects of elastic bending, viscous lubrication and body forces. We then analyze various steady and unsteady problems for the sheet such as peeling, healing, levitating and bursting using a combination of numerical simulation and dimensional analysis. On the macro-scale, we corroborate our theory with a simple experiment, and on the micro-scale, we analyze an oscillatory valve that can transform a continuous stream of fluid into a series of discrete pulses. / NSF

Electrical properties of thin film have been an issue of interest for a long time and there are many applications in contemporary industry. Interesting characteristics, such as a metal-insulator transition and superconductivity, were investigated and applied to manufacturing of various electrical devices. In this line of study, many experimental techniques have been introduced for precise measurement of the properties of thin film. Quench-condensation is one of the important techniques in the research of thin films. To facilitate this research, we built a quench-condensation apparatus which can be used for a variety of experiments. The apparatus was designed for the fabrication of ultra-thin film and the in-situ measurement at low temperature. The apparatus was shown to operate well for the fabrication of thin films while monitoring the growth in-situ. As a part of the preliminary research, we measured the electrical properties of aluminum thin films at liquid nitrogen temperature by using this apparatus. An investigation of the thickness dependent conduction properties was successively performed in-situ. Experimental data showed agreement with theory, in particular the electrical conduction model of Neugebaur and Webb.

In this thesis, we will investigate the degradation of the Low-Temperature-Polycrystalline-Silicon TFTs(LTPS TFTS) under the electrical stress. The devices are offer by Chi Mei Optoelectronics. The two mechanisms of the electrical stress are ac and dc stress. On the dc stress, we can separate the two degradation mechanisms from fixed drain voltage and various the gate voltage. The first mechanism is hot carrier effect, and second is self-heating effect. We were study the degradation mechanisms cause by above-mentioned phenomenon. On the other hand, we were confirmed the position and type of the defects by measured capacitance. In the ac stress, device degradation depends on the emission rate and energy of the hot carrier. We will study the degradation mechanism which fixed the drain voltage and various the Vg_low and falling time under different temperature. Another way of the ac stress condition will be used here. The drain and source are directly connected to ground. The gate is directly connected to the pulse. At this stress condition, carrier will push to the junction near the drain and source when gate pulse is switch from high to low. This degradation mechanism is the function of the temperature. We are going to employ a C-V measurement to examination of the defect cause by stress.

This thesis developed thin film extraction technique, which is a solid phase microextraction (SPME) technique with enhanced sensitivity, without sacrificing analysis time due to the large surface area-to-volume ratio of thin film. Thin film extraction was applied for both spot sampling and time weighted average (TWA) sampling in laboratory and on site. First, an electric drill coupled with a SPME polydimethylsiloxane (PDMS) fiber or a PDMS thin film was used for active spot sampling of polycyclic aromatic hydrocarbons (PAHs) in aqueous samples. Laboratory experiments demonstrated that the sampling rates of fiber and thin film can be predicted theoretically. The performance of a PDMS-coated stir bar at a constant stirring speed was also investigated. Compared with the fiber or the stir bar, the thin film sampler exhibited a higher sampling rate and much better sensitivity due to its higher surface-to-volume ratio and its larger extraction-phase volume. A new thin film active sampler was developed; field tests illustrated that it was excellent for rapid on-site water sampling due to its short sampling period, high sampling efficiency and durability. Second, modeling was applied to study the kinetics of fiber SPME and thin film extraction by COMSOL Multiphysics. The symmetry of absorption of analyte onto the fiber (or thin film) and desorption of calibrant from the fiber in static aqueous solution and a flow through system, was demonstrated by modeling. Furthermore, kinetic calibration method was illustrated to be feasible for fiber SPME in complex aqueous matrix and then was used to calculate the total concentration of analyte in the system. Third, thin film extraction was used in on-site sampling in Hamilton Harbour and for the determination of TWA concentrations of PAHs based on the kinetic calibration. When the thin film sampler, a fiber-retracted SPME field water sampler, and a SPME rod were used simultaneously, the thin film sampler exhibited the highest sampling rate compared to the other water samplers, due to its large surface-to-volume ratio. Fourth, partition equilibriums and extraction rates of PAHs were examined for live biomonitoring with black worms and for the PDMS thin-film in passive sampling mode. In the initial extraction stage, the extracted amounts per surface area by two samplers were similar indicating that thin-film samplers could mimic the behavior of black worms for passive monitoring. A good linear relationship between bioconcentration factors and film-water partition coefficients of PAHs demonstrated the feasibility of thin-film sampler for determining the bioavailability of PAHs in water. Finally, thin film extraction was used for the analysis of human skin and breath under different experimental conditions. Thin film technique could study several skin areas of one person, characterize the skins of different persons, and measure volatile fractions of cosmetic products that were released from the skin. The sampling time in the breath analysis could be further reduced to only 20 seconds when the thin film was rotated with a portable drill.

Electrical properties of thin film have been an issue of interest for a long time and there are many applications in contemporary industry. Interesting characteristics, such as a metal-insulator transition and superconductivity, were investigated and applied to manufacturing of various electrical devices. In this line of study, many experimental techniques have been introduced for precise measurement of the properties of thin film. Quench-condensation is one of the important techniques in the research of thin films. To facilitate this research, we built a quench-condensation apparatus which can be used for a variety of experiments. The apparatus was designed for the fabrication of ultra-thin film and the in-situ measurement at low temperature. The apparatus was shown to operate well for the fabrication of thin films while monitoring the growth in-situ. As a part of the preliminary research, we measured the electrical properties of aluminum thin films at liquid nitrogen temperature by using this apparatus. An investigation of the thickness dependent conduction properties was successively performed in-situ. Experimental data showed agreement with theory, in particular the electrical conduction model of Neugebaur and Webb.

Boiling is the most efficient form of heat transfer. Thermo-fluidic transport mechanisms at different length and time scales govern the nature of boiling. This study was conducted to enhance the understanding of the surface temperature variations and fluctuations during boiling. Microfabricated thin film thermocouples were used in this study. The main aim of this study was to develop a repeatable procedure for fabrication of thin film thermocouples and to test them by measuring surface temperatures during various boiling regimes. Since thin film thermocouples are known to provide reliable measurements at very fast response rates, they were selected for this study. Small temperature fluctuations at high sampling rates were studied in boiling experiments conducted using PF-5060 as the boiling medium. An experimental apparatus was fabricated for conducting these experiments and it contained a viewing chamber whichblock for sensing the temperature during boiling on its surface. The small size of these thermocouples was another big advantage as they were expected to cause minimal interference to the temperature distribution and the transport phenomenon during boiling. This thesis reports the design evolution of the thermocouples according to the need of packaging and describes the fabrication process with sufficient detail so that it can be easily reproduced given the same facilities and environment. The results of testing show that they can be used for monitoring and analyzing surface temperature variations and fluctuations during various boiling regimes with better temporal resolution. housed the copper block used for providing the heat for boiling. The substrate with thin film thermocouples was placed on top of this copper block for sensing the temperature during boiling on its surface. The small size of these thermocouples was another big advantage as they were expected to cause minimal interference to the temperature distribution and the transport phenomenon during boiling. This thesis reports the design evolution of the thermocouples according to the need of packaging and describes the fabrication process with sufficient detail so that it can be easily reproduced given the same facilities and environment. The results of testing show that they can be used for monitoring and analyzing surface temperature variations and fluctuations during various boiling regimes with better temporal resolution.

The subject of this dissertation is to fabricate a tunable filter for WDM applications using thin film filters (TFFs). The center-wavelength shift of the TFF was obtained by heating up the TFFs. To enhance the thermal effect on the wavelength shift of the filters, the thickness of the TFFs were reduced from 1 mm to a minims thickness of 150£gm. Si benches with etched V-grooves were fabricated for precision positioning of the TFFs after thinning. For a 200 £gm ¡Ñ 200 £gm devices, maximum wavelength shift of 1.248nm was obtained by heating up the filter to 250¢XC. In addition, the wavelength shift due to thinning the substrate of the filters is also discussed.

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In this study, the reactive rf magnetron sputtering was used to deposit P- and N-type zinc oxide (ZnO) thin films, Zinc oxide (ZnO) has higher exiton bindingenergy (60 meV) and high band gap (~3.4 eV) that can provide efficient ultraviolet (UV) light at room temperature (RT). Intrinsic ZnO is thought to be N-type primarily because of donor defects such as zinc interstitials (Zni) and oxygen vacancies (VO). we want to prepared N-doped ZnO (ZnO:N) films, we used two method : Deposition Zn3N2 films by dc sputtering of Zn target in proportional Ar and N2 mixture. After deposition, it were thermally oxidized at difference temperatures to prepared N-doped ZnO (ZnO:N) films. And to make use of rf sputtering that ZnO target in proportional Ar and N2 mixture, to prepared N-doped ZnO (ZnO:N) films. The physical characteristics of ZnO thin films with different parameter were obtained by the analyses of field emission scanning electron microscopic (FE-SEM) and XRD. The electron spectroscopy for chemical analysis (ESCA) was used to analyze the chemical states of ZnO thin films. In optical properties, the photoluminescence spectrometer was used to measure the photoluminescence characteristics (PL).