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Hall probe magnetometry measurements have been used to investigate the magnetic state of various Pb microcrystals grown by electrodeposition, where careful control of deposition parameters has allowed the tuning of their architectures. The internal flux distribution when in the superconducting state is seen to be highly dependent on the size and geometry of the investigated samples. In nanowires single flux vortex states are seen to form, showing typical type II behaviour. As the diameter of the nanowires increases these vortex states are seen to bunch together, behaviour that begins to approach that of a type I superconductor. Measurements of Pb triangles with sloped sides show the formation of giant vortex states typical of type I behaviour. These results also highlight the importance of geometry on surface barriers and the corresponding effect these have on flux distribution. Investigation of an icosahedron shows how symmetry effects can determine the stability of different flux states. Experimental results are in good agreement with Ginzburg-Landau calculations.

Diamond-Like Carbon ¡]DLC¡^films were successfully deposited on the ITO substrate by electrodeposition technique. This method has several advantages in terms of low cost, rapid growth rates and simple setup. Electrodeposition of DLC thin film was carried out at low DC potential by using a mixture of acetic acid and DI water as electrolyte. The Raman spectra showed two peaks located at 1350cm-1 and 1580cm-1, which were the characterized peaks for DLC films deposited on ITO substrates. By varying the experimental parameters such as the deposited DC potential, distance of electrodes, and the concentrations of solution, the growth mechanism of deposition process was investigated, and the best quality of DLC films was also achieved. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to make insight into accurately the surface morphology of DLC films related to deposited parameters In addition, according to the experimental results, it indicates that the quality of the DLC film was improved as deposited at higher DC voltage. Finally, to demonstrate the effect of annealing on the interfacial characteristics the C-V and G-V curves of MIS structures are the further works.

The trend to miniaturize electronic devices has led to the development of new fabrication processes. Copper electrodeposition has been used extensively in the fabrication of microelectronic circuits due to the excellent conducting properties of this metal. Control of the operating conditions and understanding of the mechanism of metal deposition is necessary in order to successfully produce the micron–scale features required in these new devices. The implementation of new processes and operating conditions in the fabrication of microelectronic devices has spurred a considerable amount of research into their understanding and improvement. An approach to achieve the desired electrodeposits is the incorporation of mixtures of chemical additives into the electroplating solutions. Many modeling and experimental studies have been devoted to exploring the mechanisms by which additives operate. However, details of these mechanisms are not completely understood. A part of this study focuses on the investigation of the conditions and dynamics of the adsorption and desorption of the additives chloride ions and polyethylene glycol (PEG) on copper substrates in voltammetry and multi–step voltammetry–chronoamperometry experiments. Voltammetry scans are classified into three categories according to the range of potentials where the inhibition of Cu2+ reduction in the presence of various concentrations of Cl− and PEG is observed. Each type is explained based on the results of this study and the ideas presented in the literature on how the conformation of adsorbed PEG on the substrate can change during the course of deposition. One of the techniques that is widely used to study electrochemical processes is electrochemical impedance spectroscopy (EIS). Insight into these processes gained from measured EIS data is better when it is combined with the use of a physicochemical model. However, the models typically used involve a number of simplifying assumptions, partly due to mathematical complications. One of the purposes of this study is to relax some of these assumptions such as the neglect of convection, migration and homogeneous reactions and investigate their effect by comparing the model results to experimental data. This approach is applied to Cu2+ reduction onto a rotating disk electrode in acidic additive–free solutions. Estimates of the kinetic parameters are obtained with the non-linear least squares method. A statistical analysis reveals that the model is further improved by accounting for the correlation between consecutive residuals. The experimental data are found to be poorly predicted when the parameters estimated from the full model are used in simpler models that do not include convection and/or homogeneous reactions. The model of Cu2+ reduction in additive–free solutions is extended to account for the presence of Cl− and PEG under transient conditions. The model accounts for the formation of the inhibiting film, blockage of adsorption sites on the electrode surface and displacement of the inhibiting film by depositing copper. A distinction is made between the condition when the electrode is completely covered with the inhibiting film and when it is only partially covered. Estimates of the kinetic parameters are obtained from fitting the model to electrode responses of linear potential scans obtained at various Cl− and PEG concentrations. The model is able to predict both the sudden loss of inhibition that occurs at intermediate Cl− and PEG concentrations and the more gradual increases in current at low and high additive levels. EIS spectra are also predicted and compared to measured ones.

The trend to miniaturize electronic devices has led to the development of new fabrication processes. Copper electrodeposition has been used extensively in the fabrication of microelectronic circuits due to the excellent conducting properties of this metal. Control of the operating conditions and understanding of the mechanism of metal deposition is necessary in order to successfully produce the micron–scale features required in these new devices. The implementation of new processes and operating conditions in the fabrication of microelectronic devices has spurred a considerable amount of research into their understanding and improvement. An approach to achieve the desired electrodeposits is the incorporation of mixtures of chemical additives into the electroplating solutions. Many modeling and experimental studies have been devoted to exploring the mechanisms by which additives operate. However, details of these mechanisms are not completely understood. A part of this study focuses on the investigation of the conditions and dynamics of the adsorption and desorption of the additives chloride ions and polyethylene glycol (PEG) on copper substrates in voltammetry and multi–step voltammetry–chronoamperometry experiments. Voltammetry scans are classified into three categories according to the range of potentials where the inhibition of Cu2+ reduction in the presence of various concentrations of Cl− and PEG is observed. Each type is explained based on the results of this study and the ideas presented in the literature on how the conformation of adsorbed PEG on the substrate can change during the course of deposition. One of the techniques that is widely used to study electrochemical processes is electrochemical impedance spectroscopy (EIS). Insight into these processes gained from measured EIS data is better when it is combined with the use of a physicochemical model. However, the models typically used involve a number of simplifying assumptions, partly due to mathematical complications. One of the purposes of this study is to relax some of these assumptions such as the neglect of convection, migration and homogeneous reactions and investigate their effect by comparing the model results to experimental data. This approach is applied to Cu2+ reduction onto a rotating disk electrode in acidic additive–free solutions. Estimates of the kinetic parameters are obtained with the non-linear least squares method. A statistical analysis reveals that the model is further improved by accounting for the correlation between consecutive residuals. The experimental data are found to be poorly predicted when the parameters estimated from the full model are used in simpler models that do not include convection and/or homogeneous reactions. The model of Cu2+ reduction in additive–free solutions is extended to account for the presence of Cl− and PEG under transient conditions. The model accounts for the formation of the inhibiting film, blockage of adsorption sites on the electrode surface and displacement of the inhibiting film by depositing copper. A distinction is made between the condition when the electrode is completely covered with the inhibiting film and when it is only partially covered. Estimates of the kinetic parameters are obtained from fitting the model to electrode responses of linear potential scans obtained at various Cl− and PEG concentrations. The model is able to predict both the sudden loss of inhibition that occurs at intermediate Cl− and PEG concentrations and the more gradual increases in current at low and high additive levels. EIS spectra are also predicted and compared to measured ones.

Diamond-like carbon (DLC) film exhibits an extreme hardness, low friction coefficient, chemical stability, heat conductivity, high resistance, and high optical transparency. There properties lead to remarkable applications such as protective and anti-reflection coating, wear resistant overcoat and biocompatible coatings. In this study, Diamond-like carbon films were deposited by electrodepsoition technique, and the deposition parameters include DC potential, deposited temperature, the concentration of electrolyte were varied to study the characteristics, microstructure and the composition of DLC film. In addition, the optimizing deposition was revealed and discussed in detail. The Diamond-like carbon film were deposited by electrodepsoition technique onto the ITO glass substrates, and the deposition conditions were preset in the range as the applied voltage from 50V and 250V, low deposition temperature within 35¢Jto 50¢J and a mixture of acetonitrile and deionized water with the concentrations of acetonitrile between 0.2% and 3.2%. Scanning electron microscopy can make an insight into the surface morphology also to reveal the uniformity of the DLC films. For the I-t curves of DLC film growth, it can be used to study of the growth mechanism by correlation the surface morphology observed by Scanning electron microscopy (SEM). The transmission, refraction index and optical band gap of DLC film was measured by the N &K analyzer. Finally, the hydrogen content, composition and microstructure of DLC films were characterized by the FTIR and XPS analyze In experimental work, the properties of DLC film obtained depends on a verity of growth parameters such as applied voltage, the concentration of electrolyte and deposition temperature. With the increase of the applied voltage, it increases with the growth rate of deposited films. That was also observed in the increase of concentration and temperature. As increase the film¡¦s thickness, the film surface becomes to the light yellow brown color, and which also causes to increase the refractive index, decrease the transmission rate, reduce the optical band gap, and decrease the amount of C-H bond and the C-N bond increase simultaneously. According to above results, DLC film deposited using the electrolyte of acetonitrile was more suitable used for coating on Si ¡Vbased optoelectronic devices such as solar cell to be a protective layer and/or anti-reflection layer. Additionally, for the nitrogen doing in DLC film, it can increase the adhesion and the friction of film to utilize for mechanic industry and to develop as the window layer of solar cells. Although there are few N-content incorporated in the DLC film, and that limits its applications. However, it still has a high potential used for solar cells and leads to advanced study in the future.

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Diamond-Like Carbon (DLC) films have been deposited on different substrates such as p-type Silicon substrate and ITO glass substrate. DLC thin film was electrodeposited at low DC potential using a mixture of acetic acid and DI water. The DLC film deposition parameters include DC potential, deposited temperature, solution concentration, are used to study the characteristics of DLC film in detail. In addition, the growth mechanism of deposition process is also discussed. We are to improve and to solve the edge induced effect on inhomogeneous film thickness during electrodeposition. The Raman spectra shows two peaks located near 1358cm-1 and 1580cm-1, assigned as the characteristics peaks of DLC films. That is an evidence for DLC film deposited successfully on ITO glass and Silicon substrates. Scanning electron microscopy (SEM) can make insight into accurately the surface morphology and uniformity of DLC films so as used to grow the best quality of DLC films. Finally, N-type of doped DLC films has been achieved on p-type silicon substrate to form the hetero-junction diode, and the intrinsic DLC film acts as the insulating layer for MIS structure is also obtained. The electrical characteristics of hetero-junction diode and MIS devices are presented and to be discussed in future.

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