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Gd2O3 and Dy2O3 thin films were grown by atomic layer deposition (ALD) on Si(100) substrates using the homoleptic rare earth guanidinate based precursors, namely, tris(N,N'-diisopropy1-2-dimethylamido-guanidinato) gadolinium (III) [Gd(DPDMG)(3)] (1) and tris (N,N'-diisopropyl-2-dimethylamido-guanidinato)dysprosium (III) [Dy(DPDMG)(3)] (2), respectively. Both complexes are volatile and exhibit high reactivity and good thermal stability, which are ideal characteristics of a good ALD precursor. Thin Gd2O3 and Dy2O3 layers were grown by ALD, where the precursors were used in combination with water as a reactant at reduced pressure at the substrate temperature ranging from 150 degrees C to 350 degrees C. A constant growth per cycle (GPC) of 1.1 angstrom was obtained at deposition temperatures between 175 and 275 degrees C for Gd2O3, and in the case of Dy2O3, a GPC of 1.0 angstrom was obtained at 200-275 degrees C. The self-limiting ALD growth characteristics and the saturation behavior of the precursors were confirmed at substrate temperatures of 225 and 250 degrees C within the ALD window for both Gd2O3 and Dy2O3. Thin films were structurally characterized by grazing incidence X-ray diffraction (GI-XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM) analyses for crystallinity and morphology. The chemical composition of the layer was examined by Rutherford backscattering (RBS) analysis and Auger electron spectroscopy (AES) depth profile measurements. The electrical properties of the ALD grown layers were analyzed by capacitance voltage (C-V) and current-voltage (I-V) measurements. Upon subjection to a forming gas treatment, the ALD grown layers show promising dielectric behavior, with no hysteresis and reduced interface trap densities, thus revealing the potential of these layers as high-k oxide for application in complementary metal oxide semiconductor based devices

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Fe/ Pt multilayers with modulation periods ⌳ = 24.1± 0.2 and 37.2± 0.1 Å and ͓110͔ ʈ ͓111͔ bcc-fcc texture were fabricated by magnetron sputtering on thermally oxidized Si wafers. The structural evolution of the multilayers with annealing temperature in the range of 300-600 K was studied by in situ x-ray diffraction ͑XRD͒ and x-ray reflectivity. Two temperature regimes were found from the XRD data. Below 534± 4 K slow, short-range diffusion is observed without significant broadening of the satellite peaks or changes in the texture. Above 534 K fast, long-range diffusion is observed accompanied by significant broadening of the satellites and rapid increase of the misorientations of the grains. The multilayers crystallize at about 583 K into the tetragonal FePt phase with a small degree of ordering and strong ͓111͔ texture. The transition resembles a first-order phase transition with a critical exponent ␤ = 0.48± 0.01 which practically does not depend on ⌳. The bulk interdiffusion coefficient, determined from the decay of the −1 satellite of the ͑001͒ Bragg peak of the multilayers, can be expressed in Arrhenius form as D͑T͒ = ͑1.37± 0.26͒ ϫ 10 −6 exp͑−1.7± 0.6/ k B T͒ m 2 / s. The gradient-energy coefficient k, entering the Cahn-Hilliard diffusion equation ͓Acta Metallurg. 9, 795 ͑1961͒, 10, 179 ͑1962͒; J. Chem. Phys. 28, 258 ͑1959͔͒, was estimated from the ⌳ dependence of the diffusion coefficient to be ͑−6.8± 0.2͒ ϫ 10 7 eV/ cm.

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