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The Li-ion field of battery research has in the latest decades made substantial progress and is seen to be the most promising battery technology due to the high volume and specific energy densities of Li-ion batteries. However, in order to achieve a battery capable of competing with the energy density of a combustion engine, further research into new electrode materials is required. As the cathode materials are the limiting factor in terms of capacity, this is the main area in need of further research. The introduction of 3-D electrodes brought new hope as the ion transportpath is decreased as well as an increased electrode area leading to an increased capacity. This thesis work has focused on the development of aluminium 3-D current collectors in order to improve the electrode area and shorten the Li-ion transportpath. By using a template assisted electrodeposition technique, nanorods of controlled magnitude and order can be synthesized. Furthermore, the electrodeposition brings excellent possibilities of upscaling for future industrial manufacturing of the batterycells. A polycarbonate template material which showed interesting properties,was used in the electrodeposition of aluminium nanorods. As the template pores were nonhomogeneously ordered a number of nonordered nanorods were expected to arise during the deposition. However, a surplus of nanorods in reference to the template pores was acquired. This behavior was investigated and a hypothesis was formed as to the mechanism of the nanorod formation. In order to achieve acomplete cathode electrode, a coating of an ion host material on the nanorods isneeded. Due to its high capacity and voltage, vanadium oxide was selected. Based on previous work with electrodeposition of V2O5 on platinum, a series of experiments were performed to mimic the deposition on an aluminium sample. Unfortunately, the deposition was unsuccessful as the experimental conditions resulted in aluminium corrosion which in turn made deposition of the cathode material impossible. The pH dependence of the deposition was evaluated and the conclusion was drawn, that electrodeposition of vanadium oxide on aluminium is not possible using this approach.

<p>When developing applications for self-assembling nanostructures, a challenge is to organize the self assembling components within integrated nano-microsystems. One approach is to impart nanostructure recognition properties to patterned surfaces, such that nanostructure placement could be thermodynamically driven. This research focuses upon self assembling nanostructures composed of DNA and their reversible specific assembly upon functionalized planar surfaces. Assembly strategies that have been developed for solution phase assembly are herein demonstrated as potentially appropriate for heterogeneous nanosystem integration.</p><p>The assembly of DNA nanostructures relies upon unique base pair interactions between single strands. While DNA hybridization that involves many base pairs results in structures that are strongly bound, an assembly strategy that underlies much DNA nanostructure engineering is formation of nanostructures at temperatures at which the interactions are weak. Here, DNA specific nanostructure immobilization is driven by weak forces. Association is characterized using surface sensitive surface plasmon resonance and quartz crystal microbalance methods. The results suggest that future strategies for nanostructure - system integration that require precise nanostructure placement may be accomplished using specific molecular recognition under thermodynamic control.</p><p>Several methods of solution phase nanostructure characterization are explored. The diffusive properties of DNA nanostructures are examined using dynamic light scattering. Effective hydrodynamic radii are found to be large relative to the nanostructure geometric size. The temperature dependence of light scattering from nanostructures is investigated using both resonance light scattering and nonresonant laser light scattering. Additionally, DNA nanostructure building block and superstructure geometry are interrogated in solution using small angle x-ray scattering. Results derived from comparison of small angle data with simulations of scattering from coarse-grained models are compared with structural information derived from imaging immobilized nanostructures with atomic force microscopy. </p><p>Finally, plasmon coupling in systems comprised of metal particles of unlike composition is described. Through simulation, three phenomena that contribute to interparticle coupling are explored. Off resonant metal particles positioned in between pairs of particles near resonance are found to promote optical coupling in a manner similar to that provided by bulk dielectric media.</p> / Dissertation

Nearly dislocation-free vertical GaN pillars in nanoscale were grown on Si (111) surface through self-assembly by molecular-beam epitaxy. No extra catalytic or nanostructural assistance has been employed. These nanorods have a lateral dimension from 10 nm to ~ 800 nm and a height of 50 nm to 3

A major challenge in the manufacturing of micro and nano devices is the cleaning, rinsing, and drying of very small structures. Without a technology for in situ and real-time monitoring and controlling, the rinse processes that account for a significant fraction of the total processing steps use a large amount of water and energy perhaps unnecessarily. This "blind" processing approach leads to waste that can have significant economic and environmental impacts. An electrochemical residue sensor (ECRS) has been developed and is aimed at in situ and real-time measurement of residual contamination inside the micro and nano structures. Using this technology, the mechanisms and bottlenecks of cleaning, rinsing, and drying can be investigated and the processes can be monitored and controlled.An equivalent circuit model was developed to assist the design of the sensor; its validity was proved by the first prototype. The simulation results and the experimental data predicted a good sensitivity in a wide range of operational frequency. To use the sensor in a practical rinse tank setup, the sensor-on-wafer prototype was designed and fabricated. Both the fab-scale and the lab-scale tests were performed and results illustrated many successes. The sensor is the first and the only available technology that provides the in situ and real-time cleanness information in the microstructures during the rinse processes. The sensor results distinguished four different types of rinse processes and showed high sensitivity to the ionic concentration change in the microstructures. The impacts of cleaning and rinsing parameters such as flow rate, temperature, cleaning solution concentrations, and process time on the sulfuric acid rinsing efficiency were investigated by using the sensor. The investigation discovered that sulfuric acid rinsing is a two-stage process: a flow-control stage and a desorption-control stage. A comprehensive rinse model was developed to correlate the transport process and the trench impedance that is the sensor's signal. This model combined with the experimental data proved that increasing flow rate in the overflow rinse has a low efficiency for the rinse processes controlled by the surface reactions. The model, for the first time, shows the dynamics of the charging of the silicon dioxide surface and the dynamics of the potential build-up in the solution. It also discovered that the cation rinsing is a challenge if the cation adsorbs on or reacts with the surface.

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The absorption of the energy in the form of heat from electromagnetic radiation is strongly dependent on the shape of the surface. Also, the transfer of this generated thermal energy is dependent on the surface area of the object in contact with the surrounding medium. Here in this thesis, we present a structural optimization method for metal nanostructures based on the shape dependency of their electromagnetic heat dissipation and thermodynamic transfer to the surroundings. We have used a parallel genetic algorithm (GA) in conjunction with a coupled electromagnetic (FDTD) and thermodynamic modeling of the metallic nanostructures for the optimization. The optimized nano-structure demonstrates significant improvement in electromagnetic heating in the spectral window of optimization as well as expedited cooling properties. The symmetry of the structures which is inherent in the design procedure makes them independent of the polarization at normal incidence and insensitive to the azimuthal direction of incidence.