In light of the escalating costs of Indium Tin Oxide, the quest for its sustainable alternatives becomes imperative. This dissertation delves into the utilization of a single-beam ion source in conjunction with magnetron sputtering to manipulate film microstructures, aiming to enhance and fabricate transparent conductive electrodes. Through the assistance of the ion source, an extensive range of modulation in the magnetron voltage was achieved. This mechanism led to a low-voltage high-current magnetron discharge, facilitating a 'soft sputtering mode' conducive for thin film growth. Indium tin oxide (ITO) thin films were successfully deposited at room temperature by employing a combined single-beam ion source and magnetron sputtering, resulting in the creation of polycrystalline ITO thin films characterized by significantly reduced resistivity and surface roughness. Notably, the ion beam treatment played a pivotal role in the growth of a silver seed layer, approximately 1 nm in thickness, enhancing the subsequent silver film's wettability. This, in turn, led to the creation of a continuous silver film of approximately 6 nm, boasting a resistivity of 11.4 μΩ.cm. To enhance stability of resulting silver ultra-thin films, an approach involving a cap layer of aluminum on silver was introduced. The resulting film, composed of a 1 nm buffer layer of ion beam-treated silver, a layer of pure silver sputter-deposited, and a 0.2 nm nominal thick cap layer of aluminum, significantly bolstered the film's stability without a marked compromise on its optical and electrical properties. Further, thermal treatment of the duplex film led to an enhancement in its electrical conductivity and optical transmittance owing to an improvement in crystallinity. The annealed aluminum/silver duplex structure exhibited low electrical resistance and high optical transmittance, comparable to simulated results, positioning it among the top films reported. The stabilized ultra-thin silver films were then leveraged to craft highly transparent and conductive electrodes on glass substrates in a sandwich structure with optimized layers of indium tin oxide (ITO). Notably, exceptional thermal stability was achieved, and annealing at 200°C in vacuum and air enhanced the film's optical and electrical performance. The resultant electrodes showcased outstanding transparency, conductivity, and thermal stability, positioning them favorably for architectural glass coatings and optoelectronic applications such as photovoltaics and displays. Further computational works were conducted to study the optical performances of six different sandwich structures on glass, comprising typical transparent conductive oxides with an ultra-thin layer of silver at 6 nm and 7 nm in the middle. The simulation finds Glass/TiO2/Ag/AZO, Glass/TiO2/Ag/SnO2 and Glass/SnO2/Ag/SnO2 structures exhibiting high optical performances, comparable to ITO in solar-cell and display applications, theoretically. This dissertation also shows some other examples of optimizing the optical performance of the structures for specific applications. Furthermore, a case study was conducted to explore the use of tantalum-doped tin oxide (TTO) as a viable alternative to ITO. Employing a room temperature treatment facilitated by a single beam ion source, highly transparent and conductive TTO films were produced. Specifically, the TTO thin film achieved a resistivity as low as 9.3 mΩ.cm and an average transmittance of 79% in the 400 nm to 1200 nm range. In contrast, without ion beam assistance, the minimum resistivity achieved was 15.9 mΩ.cm, accompanied by an average transmittance of 78% within the same wavelength range.
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