Research of thin-film batteries with solid state electrolytes based on a silicon platform is very important due to the high industrial demand for high-performance and safe batteries. Silicon, which serves as a platform for integrating thin-film batteries with semiconductor technology, is a cost-effective and widely available material. Coating the silicon platform with a graphene oxide (GO) suspension enables the integration of functional oxides onto the silicon substrate via van der Waals epitaxy. Because of GO, thin oxide layers grow in the desired orientation with a high degree of crystallinity and layer order. In addition, GO functions as an effective conductive layer that accelerates charge transfer between the semiconductor (Si) and the electrolyte, improving operational efficiency. The aim of a diploma was to deposit a suspension of GO onto a silicon substrate treated in various ways; by cleaning in a piranha solution (concentrated H$_2$SO$_4$/H$_2$O$_2$), by etching in a buffered HF/NH$_4$F solution and by plasma treatment, and to analyse the resulting surface. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, contact angle measurement, atomic force microscopy, and scanning electron microscopy were used for the characterization. Cleaning with a piranha solution has proven to be the most appropriate method, as it produces a hydrophilic surface for GO deposition, leaves only a thin layer of SiO$_2$, and results in a chemically stable surface with low roughness. Such treated surface with applied GO could be used in other studies for integration of functional layers with a pulsed laser deposition method.
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