Ion Mixing of Near-Noble Transition Metal Films on Evaporated and Large-Grained Aluminum Substrates

1987 ◽  
Vol 93 ◽  
Author(s):  
E. Ma ◽  
X.-A. Zhao ◽  
M-A. Nicolet

ABSTRACTIon mixing experiments using Xe ions at temperatures ranging from 77K to about 450K were conducted on Al/Ni and Al/Pt couples. Evaporated polycrystalline Al films and large-grained Al crystals were used as substrates. Xenon irradiation of Al/Pt bilayers achieves considerable intermixing and a temperature dependence is observed. Only moderate interfacial mixing with little temperature dependence is observed in Al/Ni bilayers. The mixing efficiency of Al/Ni is consistent with the phenomenological model of thermal spike mixing, and so is the absence of a pronounced temperature dependence below 450K. No significant difference is noted in ion mixing of evaporated and large-grained Al substrates. In contrast to ion mixing, Al/Pt and Al/Ni samples behave similarly upon thermal annealing and form well-defined compounds. The results are also compared with Si/metal systems, where silicides can be formed readily by low temperature thermal annealing as well as by ion mixing of bilayer samples.

1988 ◽  
Vol 100 ◽  
Author(s):  
E. Ma ◽  
A. J. Brunner ◽  
T. W. Workman ◽  
C. W. Nieh ◽  
X.-A. Zhao ◽  
...  

ABSTRACTInterfacial reactions induced by ion beam mixing and furnace annealing in Al/Mo bilayers are investigated. The amount of interfacial ion m'xing, 4Dt, follows a linear dose dependence for irradiation temperatures ≤80 C. Below room temperature, the mixing efficiency, defined as d(4Dt)/dø, is temperature independent, and agrees fairly well with the prediction of the phenomenological model based on chemically biased diffusion in thermal spike. We conclude that thermal spike mixing dominates for Xe irradiation of Al/Mo at low temperatures. The mixing efficiency becomes temperature-dependent above room temperature with an apparent activation enthalpy of about 0.17±0.02eV. A layer of 15–20 at.% Mo forms by ion mixing, while oAl12 Mo forms upon thermal annealing in a nonuniform fashion starting at 500°C. Reaction of Mo with large-grained Al substrates shows the same nonuniform characteristics as in evaporated Al/Mo bilayers, implying a minor role of grain boundary effects. Oxygen gettered in the Mo film could be an important factor that influences the interfacial reaction.


1995 ◽  
Vol 388 ◽  
Author(s):  
V.V. Bazarov ◽  
V.Yu. Petukhov ◽  
V.A. Zhikharev ◽  
I.B. Khaibullin

AbstractThin granular metal films in polymethylmethacrylate(PMMA) have been synthesized by 40 keV Fe+, ag+ or Pb+ ions implantation with fluencies up to 6*1017 ion/cm2. the resistivity of synthesized films was measured in the temperature range from 300K. to 5K. the temperature dependence of the resistivity of PMMA implanted with ag+, Pb+ and small fluence Fe+ obeys the well known law lnR~(l/T)1/2. the samples implanted by high fluence Fe+ reveal rather a different behaviour. at low temperature (T<100K) the curves R(T) fit the formulae inR~lnT. the two mechanisms of conductivity of a granular film are considered: direct tunneling and thermally activated hopping. Combined with the morphology features of films, obtained by high fluence Fe+ implantation, the above mentioned consideration offers a satisfactory explanation of the observed temperature dependence R(T).


1980 ◽  
Vol 41 (C5) ◽  
pp. C5-155-C5-156 ◽  
Author(s):  
T. G. Aminov ◽  
K. P. Below ◽  
V. T. Kalinnikov ◽  
L. I. Koroleva ◽  
L. N. Tovmasjan

1988 ◽  
Vol 49 (C8) ◽  
pp. C8-1657-C8-1658 ◽  
Author(s):  
C. M. Schneider ◽  
J. J. de Miguel ◽  
P. Bressler ◽  
J. Garbe ◽  
S. Ferrer ◽  
...  
Keyword(s):  

1996 ◽  
Vol 442 ◽  
Author(s):  
J.-M. Spaeth ◽  
S. Greulich-Weber ◽  
M. März ◽  
E. N. Kalabukhova ◽  
S. N. Lukin

AbstractThe electronic structure of nitrogen donors in 6H-, 4H- and 3C-SiC is investigated by measuring the nitrogen hyperfine (hf) interactions with electron nuclear double resonance (ENDOR) and the temperature dependence of the hf split electron paramagnetic resonance (EPR) spectra. Superhyperfine (shf) interactions with many shells of 13C and 29Si were measured in 6H-SiC. The hf and shf interactions are discussed in the framework of effective mass theory. The temperature dependence is explained with the thermal occupation of the lowest valley-orbit split A1 and E states. It is proposed that the EPR spectra of P donors observed previously in neutron transmuted 6H-SiC at low temperature (<10K) and high temperature (>60K) are all due to substitutional P donors on the two quasi-cubic and hexagonal Si sites, whereby at low temperature the E state is occupied and at high temperature the A1 state. The low temperature spectra are thus thought not to be due to P-vacancy pair defects as proposed previously.


Surfaces ◽  
2020 ◽  
Vol 4 (1) ◽  
pp. 1-8
Author(s):  
Tomasz Kosmala ◽  
Pawel Palczynski ◽  
Matteo Amati ◽  
Luca Gregoratti ◽  
Hikmet Sezen ◽  
...  

Here, we present a proof-of-concept experiment where phase engineering at the nanoscale of 2D transition metal dichalcogenides (TMDC) flakes (from semiconducting 2H phase to metallic 1T phase) can be achieved by thermal annealing of a TMDC/Au/mica system. The local dewetting of Au particles and resulting tensile strain produced on the TMDC flakes, strongly bound to the Au surface through effective S-Au bonds, can induce a local structural phase transition. An important role is also played by the defects induced by the thermal annealing: when vacancies are present, the threshold strain needed to trigger the phase transition is significantly reduced. Scanning photoelectron microscopy (SPEM) was revealed to be the perfect tool to monitor the described phenomena.


2020 ◽  
Vol 42 (2) ◽  
Author(s):  
Thomas Leitner ◽  
Anna Werkovits ◽  
Siegfried Kleber ◽  
Gernot Pottlacher

AbstractW360 is a hot work tool steel produced by voestalpine BÖHLER Edelstahl GmbH & Co KG, a special steel producer located in Styria, Austria. Surface tension and density of liquid W360 were studied as a function of temperature in a non-contact, containerless fashion using the oscillating drop method inside an electromagnetic levitation setup. For both, surface tension and density, a linear model was adapted to present the temperature dependence of these measures, including values for the uncertainties of the fit parameters found. The data obtained are compared to pure iron (with 91 wt% the main component of W360), showing an overlap for the liquid density while there is a significant difference in surface tension (− 5.8 % at the melting temperature of pure iron of 1811 K).


2020 ◽  
Vol 147 ◽  
pp. 01015
Author(s):  
Dimas Fendy Pradana ◽  
Ignatius Hardaningsih ◽  
Dini Wahyu Kartika Sari

The objectives of this study were to evaluate the sperm viability of Najawa carp (Cyprinus carpio L.) in cryopreservation pre-conditions at 4°C. The design used in this study was Complete Randomized Design with 4 treatments, BSS as a control, 10% DMSO, 0,2 M Sucrose, and 5% DMSO + 0,1 M Sucrose; each consist of three replications. The parameters observed were progressive motility of fresh sperm, diluted sperm before low temperature storage, and 2 hours; 3 hours; 4 hours; 5 hours; one day; one week; a month after 4°C storage. The data were analyzed by ANOVA. The data showed that there was no significant difference between treatment (P>0.05). The best viability was 40.56% of sperm motility which survive for one week, it was achieved by 5% DMSO + 0,1 M Sucrose.


Sign in / Sign up

Export Citation Format

Share Document