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The reaction of a Ni 0.9 Pt 0.1 7 nm-thick thin film with the underlying Si(001) substrate as a function of the annealing temperature was studied using in situ XRD techniques as well as ex situ advanced XRD and TEM imaging on quenched samples. It was found that the Ni 0.9 Pt 0.1 /Si system initially evolves accordingly to diffusion controlled reactions via the development of nano-crystalline Ni-rich Ni 1 − x (Pt) Si x phases that combine the ability of fast kinetic growth and texture inheritance. The system remains then stable over some tens of degrees before Ni(Pt)Si nucleation occurs, once the related energetic barrier is overcome. It was additionally found that this newly observed phase sequence remains valid up to Ni 0.9 Pt 0.1 deposited layer thicknesses of about 16 nm, which is remarkable for such systems. [ABSTRACT FROM AUTHOR]

The formation of Ti based contacts in new image sensor complementary metal–oxide–semiconductor technologies is limited by the requirement of a low thermal budget. The objectives of these new 3D-technologies are to promote ohmic, low resistance, repeatable, and reliable contacts by keeping the process temperature as low as possible. In this work, ultraviolet-nanosecond laser annealing was performed before classical rapid thermal annealing (RTA) to promote the formation at lower RTA temperatures of the low resistivity C54-TiSi2 phase. The laser energy density was varied from 0.30 to 1.00 J/cm² with three pulses in order to form the C40-TiSi2 phase and finally to obtain the C54-TiSi2 phase by a subsequent RTA at low temperatures. The formed Ti-silicides were characterized by four-point probe measurements, x-ray diffraction, transmission electron microscopy, and atom probe tomography. A threshold in the laser energy density for the formation of the C40-TiSi2 is observed at an energy density of 0.85 J/cm² for the targeted TiN/Ti stack on blanket wafers. The C40-TiSi2 formation by laser annealing prior to RTA enables to reduce the formation temperature of the C54-TiSi2 phase by 150 °C in comparison to a single RTA applied after the Ti/TiN deposition. This specific phase sequence is only observed for a laser energy density close to 0.85 J/cm². At higher energy densities, the presence of C49-TiSi2 or a mixture of C49-TiSi2 and C54-TiSi2 is observed. The underlying mechanisms of the phase sequence and formation are discussed in detail. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.06.032 Byline: J. Vaucher (a), D. Baratoux (a), N. Mangold (b), P. Pinet (a), K. Kurita (c), M. Gregoire (a) Keywords: Mars; Volcanism Abstract: Central Elysium Planitia (CEP) is located south of Elysium Mons. Back to the era of the Viking orbiters, clues accumulated in favor of recent volcanism in relation with ground water release and the formation of long sub-parallel fissures. Four aqueous flood channel systems emanate from linear fissures. Recent eruptions of low viscosity lavas originate from these fissures and from low shield volcanoes. The objective of this paper is to constrain the volcanic history of this region, and to determine the chronological relationships with fluvial/erosional processes. New observations (e.g., new shield volcanoes and one new fluvial event) are summarized on a context map. Thirty-five surfaces have been dated from the count of about 15,000 impact craters. Ages have been cross-checked with relative stratigraphy when possible. A probabilistic approach has been introduced to compare similar ages and define periods of volcanic activity. Our results confirm that some volcanic features are extremely recent ([approximately equal to]2My). Active periods are found at 2.5-3My, 4.3My, 13.5-16.2My, 19My, 21-32My, 58My, 71My, 85-95My, 134My, 173My and 234My, not excluding the possibility that some of the gaps would be filled with additional crater counts. The volcanic activity thus extended for at least the last 250My. The lava volumes have been estimated from the topographic modeling of the floor of depressions filled up by volcanic products, including the volumes of several large crater cavities buried under lavas (>20% of the total volume). Our new estimation of the total lava volume is 1.5[+ or -]0.2x10.sup.5 km.sup.3. This value corresponds to an average thickness of one hundred meters of lavas for the young volcanic plain. As a consequence, the total eruption rate at CEP, defined as the total volume of lava divided by the time of emplacement 1.4x10.sup.-2-1.8x10.sup.-2 m.sup.3/s is lower than values typically estimated for terrestrial hot spots or large igneous provinces, suggesting longer inactive periods. The concept of mantle plumes responsible for terrestrial flood volcanism may not be applicable to the case of CEP and the mechanism proposed in offers a plausible alternative to explain our observations. Author Affiliation: (a) Laboratoire Dynamique Terrestre et Planetaire, UMR 5562, Observatoire Midi-Pyrenees, Universite de Toulouse and CNRS, Toulouse, France (b) Universite de Nantes, UFR des Sciences et des Techniques, Laboratoire de Planetologie et Geodynamique, 2 rue de la Houssiniere, B.P. 92208, 44322 Nantes Cedex 3, France (c) Earthquake Research Institute, Zip. 113-0032, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, Japan Article History: Received 12 June 2007; Revised 17 May 2009; Accepted 1 June 2009