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Ru films are grown on Pt, TiN, and SiO2 substrates via atomic layer deposition (ALD) using Ru(II)(η5‐C7H7O)(η5‐C7H9) as the novel Ru metalorganic precursor and O2 as the reactant. The ALD self‐limiting film growth is confirmed at the low temperature of 200 °C by manipulating the injection time and purge time of the Ru precursor and O2, and the saturated growth per cycle is 0.22 Å cy−1. It is confirmed that the combustion reaction occurs during the deposition process from the formation of the H2O and CO2 by‐products. Thin films with a low resistivity of 17–19 µΩ cm are grown at a thickness of ≈15 nm. The Ru incubation times are remarkably short at 200 °C (negligible on Pt, ≈30 cycles on TiN and SiO2), but increase with increasing temperature. The energy dispersive X‐ray mapping image of the Ru film on the pattern in which TiN is formed on SiO2 shows that the Ru film with a novel precursor has the intrinsic substrate selectivity at the deposition temperature of 300 °C. Furthermore, the substrate affects the properties of the Ru film. Particularly because Ti serves as an oxygen reservoir, a relatively large amount of RuOx is produced on the TiN substrate. [ABSTRACT FROM AUTHOR]

New heteroleptic indium complexes, i. e. [MeIn(mdpa)(tmhd)]2 (2), [MeIn(mdpa)(acac)]2 (3), [MeIn(edpa)(tmhd)]2 (4), and [MeIn(edpa)(acac)]2 (5), with three different ligands, bearing N‐alkoxy carboxamide and β‐diketonate were designed and synthesized as indium precursors for indium oxide thin films by atomic layer deposition (ALD) using [Me2In(edpa)]2 and [Me2In(mdpa)]2 (1) as starting materials. The resulting complexes were characterized by NMR and FT‐IR spectroscopy, elemental analysis (EA), thermogravimetric analysis (TGA), and single crystal X‐ray diffraction. TGA curves of all the complexes showed clear single‐step weight losses, with low residual masses of 7–13 %. Among them, complex 5 was volatile and thermally stable, and thus, it can be used as potential indium precursor for indium oxide‐based thin films. [ABSTRACT FROM AUTHOR]

Phase change random access memory appears to be the strongestcandidatefor next-generation high density nonvolatile memory. The fabricationof ultrahigh density phase change memory (≫1 Gb) depends heavilyon the thin film growth technique for the phase changing chalcogenidematerial, most typically containing Ge, Sb and Te (Ge–Sb–Te).Atomic layer deposition (ALD) at low temperatures is the most preferredgrowth method for depositing such complex materials over surfacespossessing extreme topology. In this study, [(CH3)3Si]2Te and stable alkoxy-Ge (Ge(OCH3)4) and alkoxy-Sb (Sb(OC2H5)3) metal–organic precursors were used to deposit variouslayers with compositions lying on the GeTe2–Sb2Te3tie lines at a substrate temperature as lowas 70 °C using a thermal ALD process. The adsorption of Ge precursorwas proven to be a physisorption type while other precursors showeda chemisorption behavior. However, the adsorption of Ge precursorwas still self-regulated, and the facile ALD of the pseudobinary solidsolutions with composition (GeTe2)(1-x)(Sb2Te3)xwereachieved. This chemistry-specific ALD process was quite robust againstprocess variations, allowing highly conformal, smooth, and reproduciblefilm growth over a contact hole structure with an extreme geometry.The detailed ALD behavior of binary compounds and incorporation behaviorsof the binary compounds in pseudobinary solid solutions were studiedin detail. This new composition material showed reliable phase changeand accompanying resistance switching behavior, which were slightlybetter than the standard Ge2Sb2Te5material in the nanoscale. The local chemical environment was similarto that of conventional Ge2Sb2Te5materials. [ABSTRACT FROM AUTHOR]

A phase change memory cell was fabricated by stacking plasma-enhanced cyclic chemical-vapor-deposited Ge2Sb2Te5 (GST) and atomic layer deposited TiO2 thin films. Different pairs of resistance states were obtained by controlling the current flow, which can be used to achieve higher memory density by multilevel operation. The multiresistance states of the stacked cell were explained by the resistance switching phenomena of TiO2 and the thermoelectric phase change properties of GST. The phase change characteristics of GST could be altered by controlling the degree of filament formation in the TiO2 layer, which eventually changed the phase change volume in the GST. [ABSTRACT FROM AUTHOR]

Series of niobium precursors with imido group and N -alkoxy carboxamide ligands were synthesized and fully analyzed by NMR, FT-IR, EA and TGA. All prepared complexes were able to be distilled and sublimed under reduced pressure, and expected potential precursors for niobium containing films. [Display omitted] A series of novel Nb(V) t Bu-imido/ N -alkoxy carboxamide complexes, NbCl 2 (N t Bu)(pyridine)(edpa) (1), NbCl 2 (N t Bu)(pyridine)(mdpa) (2), and Nb(N t Bu)(mdpa) 3 (3), were successfully synthesized by metathesis reaction between Nb(N t Bu)Cl 3 (py) 2 and several equivalents of Na(edpa) (edpaH = Nethoxy-2,2-dimethylpropanamide) and Na(mdpa) (mdpaH = N -methoxy-2,2-dimethylpropanamide). These complexes could potentially serve as precursors for Nb-containing thin films. Compounds 1 – 3 were characterized by FT-IR and 1H and 13C NMR spectroscopies, elemental analysis, and thermogravimetric analysis (TGA). Single crystal X-ray diffraction analysis suggested that complex 3 has a distorted pentagonal bipyramidal geometry around the central Nb atom, with three bidentate mdpa ligands and one t Bu imido group saturating the coordination. TGA analysis revealed that the thermal characteristics of 3 were superior to those of 1 and 2. All prepared complexes were able to be distilled or sublimed and expected potential precursors for the fabrication of thin films. [ABSTRACT FROM AUTHOR]