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Magnesium oxide has potential applications as a transistor gate dielectric material having a dielectric constant over twice SiO2 and a bulk bandgap of 7.3eV. The high chemical stability of MgO should promote the formation of abrupt interfaces with semiconductor substrates. In this study, the growth, stochiometry and crystallography of MgO thin films, deposited by electron beam evaporation, have been investigated. Films of different thickness were deposited on the native oxides of Si(111) and InP(100) substrates and following chemical passivation procedures in order to determine the effect which factors such as deposition rate, film thickness, substrate temperature and substrate ionicity have on film growth. Using atomic force microscopy (AFM) the predominant film growth mechanism was found to be Volmer Weber, with factors such as deposition rate and film thickness determining the height at which 3 dimensional islands coalesce to form a continuous film. Chemical characterisation using X-ray photoelectron spectroscopy (XPS) showed that deposition on hydrogen terminated silicon surfaces produced films of more uniform thickness than those deposited on the silicon native oxide surface. XPS spectra of the O1s core level exhibits two oxygen peaks, a lower binding energy peak which can be attributed to the lattice oxygen in the MgO, along with a higher binding energy (HBE) oxygen peak. The continued growth to this HBE oxygen peak following exposure to ambient conditions provided strong evidence that this peak is not due to the magnesium peroxide species MgO2 and was attributed to a hydroxyl species which bonds to the surface of the MgO upon exposure to air. Deposition at elevated substrate temperature (500K) was shown to reduce the growth of this hydroxyl species in air and this was attributed to the fact that, as these films were more uniform, there was less available surface area for the hydroxyl groups to attach. Increasing the substrate temperature during deposition was shown to improve the stochoimetry of the film. X-ray diffraction measurements were taken in order to determine the crystalline state of the films. |