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The temperature dependent thermal conductivity of In-Sb-Te thin films has been measured by modulated photothermal radiometry in the 20-550 °C range for samples with different Te content. Significant changes with temperature are observed and ascribed to a sequence of structural transformations on the basis of in-situ Raman spectra. The data suggest that the as-deposited material consisting of a mixture of polycrystalline InSb0.8Te0.2and amorphous Te first undergoes a progressive crystallization of the amorphous part, mostly above 300 °C. Further increase in temperature above 460 °C leads, for higher Te content in the alloy, to the formation of crystalline In3SbTe2, intertwined with a less conductive compound, possibly InTe and/or InSb. Upon cooling to room temperature, the initial polycrystalline InSb0.8Te0.2phase is mostly recovered along with other compounds, with a slightly higher thermal conductivity than that of the as deposited material. (© 2016 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Nickel silicide is considered the best candidate material to achieve the lowest contact resistance in sub 45 nm CMOS devices. NiSi films with thickness 20-60 nm were prepared by rapid thermal annealing of Ni (temperature 230 °C-780 °C) on top of thin 230 nm silicon-on-insulator substrates, with a constant formation ratio. Based on film independent characterizations, a novel model for the interpretation of spectroscopic ellipsometry data, featuring a combination of two Lorentzian oscillators and one Drude dispersion model, is proposed, and its goodness is checked in comparison to other known models. This new approach is proved to deliver more accurate estimation of the film thickness and resistivity. [ABSTRACT FROM AUTHOR]

Abstract: The interest in the Ge doped Sb–Te chalcogenide alloy is mainly related to phase change memory applications. In view of phase change device scaling and reduction of programming energy, Sb–Te nanowires (NWs) become an attractive option. In this work, in order to investigate their potential transferability to industrial implementation, the self-assembly of Sb2Te3 NWs and Ge–Sb–Te NWs with Ge content in the range of 1–13% (Ge doping) was studied by coupling the advantages of MOCVD and the Vapour–Liquid–Solid (VLS) mechanism. The results show the structural and compositional gradual changes occurring from pure Sb2Te3 NWs to the previously reported, stoichiometric Ge1Sb2Te4 NWs [[12] M. Longo et al., Nano Lett., 12 (2012) 1509]. The typical diameter of the obtained NWs resulted to be 50nm, with lengths up to 3μm. The typology of Au catalyst nanoislands influenced both the NW morphology and the Ge incorporation during the VLS self-assembly; the Ge metalorganic precursor partial pressure affected the NW morphology and their structure. Finally, TEM observations revealed that defect-free, monocrystalline Sb2Te3 and Ge-doped Sb–Te phase change NWs could be obtained. [Copyright &y& Elsevier]

Abstract: We report on the bubbler-type MOCVD growth of Ge x Sb y Te z (GST) on SiO2/Si substrates, potentially transferable to phase change memory (PCM) devices. Pure nitrogen was used as the process gas in order to reduce toxicity whilst increasing the simplicity of the process. This systematic study allowed the modification of the growth parameters on SiO2 to move through initial sub-micrometric crystalline grain deposition on to lateral island growth. Temperature was observed to play a critical role in film quality with strong morphology and island shape/size changes for small thermal variations. Eventually, continuous layers of GST in the hcp phase and composition close to the 2:2:5 were studied. The deposition on different substrates was also investigated. Although crystal nucleation is still far from achieving the target step coverage required for uniform coating of patterned substrates, the electrical sheet resistance of GST films exhibited values corresponding to those expected for chalcogenide materials suitable to be integrated into PCM devices. [Copyright &y& Elsevier]