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Item Surface Chemistry and Interface Evolution during the Atomic Layer Deposition of High-k Metal Oxides on InAs(100) and GaAs(100) Surfaces(2015-01-01) Henegar, Alex J.; Gougousi, Theodosia; Physics; Physics, AppliedDevice scaling has been key for creating faster and more powerful electronic devices. Integral circuit components like the metal-oxide semiconductor field-effect transistor (MOSFET) now rely on material deposition techniques, like atomic layer deposition (ALD), that possess atomic-scale thickness precision. At the heart of the archetypal MOSFET is a SiO₂/Si interface which can be formed to near perfection. However when the thickness of the SiO₂ layer is shrunk down to a few nanometers several complications arise like unacceptably high leakage current and power consumption. Replacing Si with III-V semiconductors and SiO₂ with high-k dielectric materials is appealing but comes with its own set of challenges. While SiO₂ is practically defect-free, the native oxides of III-Vs are poor dielectrics. In this dissertations, the surface chemistry and interface evolution during the ALD of high-k metal oxides on Si(100), GaAs(100) and InAs(100) was studied. In particular, the surface chemistry and crystallization of TiO₂ films grown on Si(100) was investigated using transmission Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Large, stable, and highly reactive anatase TiO₂ grains were found to form during a post-deposition heat treatment after the ALD at 100°C. The remainder of this work was focused on the evolution of the interfacial oxides during the deposition of TiO and Al₂O₂ on InAs(100) and GaAs(100) and during the deposition of Ta₂O₂ on InAs(100). In summary the ALD precursor type, deposited film, and substrate had an influence in the evolution of the native oxides. Alkyl amine precursors fared better at removing the native oxides but the deposited films (TiO₂ and Ta₂O₂) were susceptible to significant native oxide diffusion. The alkyl precursor used for the growth of Al₂O₂ was relatively ineffective at removing the oxides but was a good diffusion barrier. In all cases the native oxides were more stable on GaAs compared to InAs. This project utilized a new methodology for the detection of arsenic oxide diffusion using transmission FTIR, and expanded the knowledge of the complexities of the high-k/III-V interface.