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Diamond-Like carbon (DLC) films has a lot of advantages, such as high hardness, high thermal conductivity, low expansion coefficient, low friction coefficient, high chemical stability, high impedance. These properties make the DLC films suitable for becoming an insulator in metal insulator semiconductor structure. In this study, DLC films were deposited by electro-deposition technique onto silicon (Si) substrates, in which a mixture of acetic acid and water is used as the electrolyte. The structure of the DLC films is characterized by Raman Spectroscopy. The thermal evaporation technique was used to deposit an aluminum films on the DLC/Si-substrates, to make it as the structure of metal-insulator semiconductor (MIS), and the electrical properties of the MIS were measured by semiconductor parameter analyzer. DLC films were deposited by varying the parameters of electro-deposition process included mainly as the concentration of solution, the spacing between electrode and silicon substrate, deposition temperature, and the applied voltages. The properties and film growth of DLC attributed to the effect of parameters were described in detail. Finally, an electro-deposition model is obtained to describe the growth mechanism of electro-deposition of DLC film.

This thesis utilized the characteristics of the external cavity system including the wavelength tuning and the multi-channel output, and using the Quantum Confined Stark Effect (QCSE) by adding the bias on the electro-absorption modulator to build a new method of the Q-switched modulation .The method made the wavelength tuning and multi-channel output of high speed Q-switched external cavity semiconductor laser with the colinear output come true . The system of the external cavity semiconductor laser with the electro-absorption modulator making of the VCSEL with the wavelength 850nm and 830nm could be modulated to 63ns . The tuning range could be up to 0.9nm . Each of the channel would be separated into 0.2nm . We could obtain the two channels output by using the double electro-absorption modulators on the specific position .The distance of the wavelength is 4.61nm.

Thesis (M.S.)--Florida State University, 2003. / Advisor: Dr. Ravindran Chella, Florida State University, FAMU-FSU College of Engineering, Dept. of Chemical Engineering. Title and description from dissertation home page (viewed Sept. 26, 2003). Includes bibliographical references.

Theoretical studies are presented in this thesis on the hydrodynamic dispersion due to electro-osmotic flow (EOF) through a parallel-plate or circular channel under the combined effects of wall heterogeneities, including surface topography, hydrodynamic slip, and zeta potential. These wall properties, which are periodically varied along the channel, are called wall patterns in general. The electric potential field and the velocity field of the EOF are determined by solving the linearized Poisson-Boltzmann (P-B) equation and the Stokes equation, respectively, subject to the spatially varying electrohydrodynamic boundary conditions caused by the wall patterns. In particular, for wall patterns with discrete step changes (in contrast with slowly varying and continuous ones), the solutions are expressed by Fourier series that satisfy the mixed-type boundary conditions. The effective expression for the dispersion is derived using the theory of homogenization by introducing multiple-scale variables and expansions. The effective dispersion coefficient is determined either by purely analytical analysis or numerical methods combined with analytical deduction, depending on the complexity of the problem formulation. This thesis consists of two parts. In the first part, the aggregate effect on the flow due to non-uniformly distributed wall properties is studied in two problems. The first problem considers the combined effects of wall corrugations and slippage modulation on pressure-driven cross (transverse) flow through a thin parallel-plate channel in terms of the hydrodynamic effective slip length and flow enhancement. The second problem considers the combined effects of charge distribution and slippage modulation on both longitudinal and transverse EOF through a channel with the same geometry in terms of the electroosmosis (EO) mobility and flow morphology. It is shown that the interaction between different wall patterns due to surface heterogeneity can play a significant role in determining the flow velocity as well as the local convection pattern, both quantitatively and qualitatively. In the second part, hydrodynamic dispersion due to EOF under the aggregate effect of surface heterogeneities in wall potential and hydrodynamic slippage is studied also in two problems. The first problem considers a limiting case where certain geometric and dynamic requirements are satisfied so that the theory of lubrication approximation can be applied to simplify the analysis, for which analytical solutions are obtained for the flow as well as the dispersion. The second problem is for a similar but more general case without using the lubrication approximation, in which the velocity of the flow, the dispersion coefficient and the plate height for the mass transfer are numerically determined after the mathematical formulation of the problem. It is remarkable that the introduction of hydrodynamic slippage can dramatically change the dispersion arising from EOF in various aspects, especially when both the slippage and electric potential are non-uniformly distributed on the channel wall. / published_or_final_version / Mechanical Engineering / Master / Master of Philosophy

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Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 162-174). Also available via the Internet.

Thesis (M.S.)--Brigham Young University. Department of Mechanical Engineering, 2004. / Includes bibliographical references (p. 79-81).