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The early oxynitridation stages of hydrogen-terminated (100) silicon after exposure to N2:N2O. II. Silicon and oxygen bonding states
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Ultradense gas bubbles in Hydrogen- or Helium-implanted (or co-implanted) Silicon
No full textUltradense gas bubbles in Hydrogen- or Helium-implanted (or co-implanted) Silico
Evidence for H-2 at high pressure in the silicon nanocavities after dipping in HF solution
No full textThe immersion in HF solutions of silicon containing nanocavities (produced by the annealing at high temperature, 950 degrees C, of silicon implanted with helium at high fluence, 2 X 10(16) cm(-2)) results in the injection of hydrogen in an infrared-mute state (most likely HA into the nanocavities. The pressure achieved in the cavities is sufficiently high to stabilize the hydrogen coverage of the inner surfaces at: temperatures exceeding by 200 degrees C the one of complete desorption from the outer surface
High-dose helium-implanted single-crystal silicon: Annealing behavior
No full textThe modifications induced in single-crystal silicon by implanted helium have been investigated by ion beam techniques. The damage has been detected by 2 MeV 4He+ backscattering in channeling conditions and the helium in-depth distribution by 7 and 8 MeV 15N++ elastic recoil scattering. The samples prepared by implanting 2×1016 cm−2 helium ions at 20 keV in silicon wafers held either at 77 K (LNT sample) or at 300 K (RT sample) have been heat treated for 2 h in the 100–800 °C temperature range. In the as-implanted LNT sample the damage maximum is at 130±20 nm and shifts in-depth to 180±10 nm after annealing at 200 °C, in the as-implanted RT sample, the damage maximum is already located at 180±10 nm. In the 250–500 °C temperature range, the LNT and RT samples follow the same annealing path with only slight differences in the temperature values; in both cases, the dechanneling signal increases and reaches a maximum value of nonregistered silicon atoms of 2.2–2.5×1022 at/cm3. In the same temperature range, the helium signal becomes narrower, builds up in a region centered on 220±20 nm and no appreciable loss of helium can be detected. The growth of the damage is consistent with the creation of cracks and a etherogenous distribution of bubbles filled with high pressure helium which stress the lattice; for the channeling Rutherford backscattering technique, their action is similar to silicon interstitials. At temperatures above 500 °C, helium is released from the samples; this process is associated with a decrease of the damage and the formation and increase in size of voids. At 900 °C empty voids with a diameter around 20 nm are found
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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