الفهرس 
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Abstract
Aluminum – Ruthenium (Al/Ru) system has its importance in both bulk and nanostructured forms for its different industrial applications as corrosion resistant coatings and micro-electronic devices. Scientific investigations have recorded that bulk Al/Ru alloys have undefined limits in their equilibrium phase diagram. Many factors are still not clear in Al/Ru phase formation in bulk and moreover for the nanostructure form. Nanocrystalline Al/Ru bi-layers thin films not been investigated. This work is devoted to study the bi-layer Al/Ru interface phase formation conditions. This study has been performed through two synthesis methods, the DC magnetron sputtering and the ion beam plasma sputtering for depositing nanostructured thin films. Different elaboration, preparation and post deposition condition of Al/Ru thin film were discussed as starting condition for layer thickness limits, substrate type, annealing temperature and annealing times. Many techniques were used to characterize the bi-layer intermetallic phase formation through cross section morphology, homogeneity structure and crystallite size as Focused ion beam (FIB), grazing incidence X-ray diffraction (GIXRD), scanning and transmission electron microscopy (SEM, TEM), and energy dispersion analysis of x-ray (EDX). Silicon single crystals have been used as substrate for depositing Al/Ru bi-layers nanostructure thin films using DC magnetron sputtering machine. No phase change occurs until 300oC, for short annealing time ≤ 45 min for as sputtered Al/bi-layers of individual thicknesses, 1150 nm Al and 940 nm Ru. Temperature induced changes after increasing time from 10 to 2880 min annealed in vacuum at 500oC for small thicknesses 287 nm Al and 235 nm Ru were studied. Grazing incidence X-ray diffraction indicates RuAl2 phase formation after 45 minutes annealing at 500oC for as sputtered Al/Ru bi-layers. Electron diffraction pattern of thin foil from annealed bi-layers shows spots for RuAl2 and Al6Ru phases. Focused ion beam (FIB) cross sections showing non-uniform 500 nm thickness reaction layers at the Al/Ru interface. Decreasing Al thicknesses to 287 nm Al and 235 nm Ru at a fixed ratio of Ru/Al equals 1.224 reduces the time required to start the reaction at the same temperature. Al layer was completely consumed after 30 minutes annealing at 500oC while Ru layer was still not completely reacted until 2880 minutes annealing as shown by FIB cross sections. Formed intermetallic phase layer acts as a diffusion barrier that controls further atomic diffusion from both Al and Ru sides into the formed reaction layer. Focused Ion Beam technique proved high efficiency in revealing the reaction zone at the Al/Ru bi-layers interface as reaction starts. Samples covered with platinum as a protective layer during cutting and high voltage beam level helped in EDX and FIB image clarity as well as electron beam penetration and ion beam images spatial resolusion. Al6Ru was the only formed phase after annealing for 2880 min at 500oC on the Al foil substrate and 240 min at 550oC, 600oC for samples of 90 nm Ru thick layer sputtered on 520000 nm thick Al foils. Sputtered Al layers on single crystal silicon substrates of increasing thicknesses from 280 nm to 2300 nm shows RuAl2 intermetallic phase formation at 280 nm Al layer and Ru4Al13 and Al6Ru phases in the range from 575 to 2300 nm at constant Ru thickness of 187 nm cover layers after 2880 minutes annealing at 500oC. Only Al6Ru phase has formed in samples of 520000 nm thickness Al foil used as substrate covered with the same 187 nm Ru layer. Atomic compositions were calculated from an equation which relates the thickness ratios at one side, atomic densities for both Al and Ru and atomic composition ratio at the other side. Multilayers of 136 layers of Al and Ru films were sputtered all over each other on glass substrate using ion beam plasma sputtering. The effect of individual layer thickness and temperature and time of annealing on the phase formation were studied. Grazing incidence X-ray diffraction patterns showed that, as sputtered of samples small thicknesses (3 nm Al and 2.5 nm Ru) contains only points of RuAl intermetallic phase. No phase change is shown for annealed samples at 500oC with increasing annealing time from 300 to 1200 min. The cross sections made with FIB for the formation of RuAl showed one layer structure. Increasing the sputtered thickness at constant molar volume ratio of 1.224, where the Al thickness increases from 5 to 10 nm and the Ru from 4 to 8.3 nm, revealed peaks of RuAl intermetallic phase and non-reacted Al metal were found, which may be due to excess sputtered Al which had not reacted. Annealing at 500oC for 1200 min shows Al6Ru intermetallic phase peaks, which may be due to the reaction of excess Al with the RuAl phase. FIB cross section for as sputtered samples showed that sputtered layers have faint boundaries due to the formation of RuAl intermetallic compound between the layers in addition to excess aluminum which did not diffuse during the sputtering process. Crystallite size increased in (110) direction with increasing thickness and with annealing time and temperature at 500oC for 1200 min. Crystallite size variation corresponds to very small amount increase in nanograin thin films due to annealing process. All films were measured from one crystallographic direction (110), the most oriented direction in grazing incidence Al/Ru multilayers diffractograms, to avoid direction effect on crystallite size measurement. It was concluded that definite elaboration, preparation and post deposition parameters were determined for formation Al/Ru intermetallic single and multiphase nanocrystalline layer (as RuAl, RuAl2, Al6Ru and Ru4Al13). The results reflect that nanocrystalline Al/Ru bi-layers reach the intermetallic phases at lower annealing times and temperatures with respect to its formation as bulk alloys.