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Growing interest has been dedicated on the production of III-V nitride compounds (AlN, GaN, InN) due to the high potential of practical optical and electronic applications. InN films, grown by Ion Beam Assisted Deposition Technique, where the bombardment with energetic particles (nitrogen) was used as excitation source, were deposited on a-plane, c-plane, and r-plane sapphire, on GaN/a-plane sapphire templates, and on glass (CORNING 7059). Ion implantation energies of 100 eV and arrival rate ratio, ARR (N/In) (which is the ratio between the number of evaporated indium atoms by the electron gun and the number of accelerated ions that simultaneously arrive at the substrate) between 0.8 and 5.5 were employed. Substrate temperatures of 30 (RT), 100, 200, 300 or 450°C were used during film growth. Films with thicknesses of 50 nm, as controlled by quartz oscillator thickness monitor, were produced. X-ray diffraction patterns showed that the deposited films contained crystalline InN and metallic indium components, and/or amorphous InN structure. SEM studies showed rough surfaces for almost all samples, except for samples grown at room temperature. The XPS was employed to analyze the indium and nitrogen bonding states and to estimate the composition ratio between indium and nitrogen atoms in the films. XPS studies were carried out for In - 3d5/2 and N - 1s peaks, which yield the composition ratio based on the area ratio of the respective peaks. For films on GaN/a-plane sapphire templates grown at room temperature, the XPS spectra showed In - 3d5/2 peaks at 444.7 eV. This peak can be attributed to the presence of InN, according to the literature. XPS shows different phases of In, InN, InON on different substrates. Raman shows E2(high) and A1(LO) for growth on glass at RT - 450°C. Raman and FT-IR results will be presented to provide additional information on the films crystalline quality. |