Study of Hf Diffusion in A-Zr using Rutherfdrd Bacckscrttering Spectroscopy

1989 ◽  
Vol 157 ◽  
Author(s):  
F. Dyment ◽  
M. Behar ◽  
H. Oners ◽  
P.L. Grande ◽  
E. Savino ◽  
...  

ABSTRACTThe present contribution reports on measurements of the diffusion coefficients of Hf in a-Zr via the RBS technique. 250 8 Hf thin films were deposited on two kinds of polycrystalIine Zr samples and annealed in a 773-1115 K temperature range. Our results show that in both cases, the diffusion coefficients follow curved flrrhenius plots. On the other hand for the purest Zr sample we have obtained diffusion coefficients that are systematicaly and significativel ly lower than those corresponding to the Zr sample richer in impurities.

2020 ◽  
Vol 312 ◽  
pp. 3-8
Author(s):  
L. Dermenji ◽  
K.G. Lisunov ◽  
Konstantin Nickolaevich Galkin ◽  
Dmitrii L. Goroshko ◽  
E.A. Chusovitin ◽  
...  

Resistivity, r (T), and Hall coefficient in weak (B < 1 T) magnetic fields, R (T), are investigated in Ca2Si and CaSi2 films at temperatures T between ~ 20 - 300 K. In CaSi2, r (T) is typical of metals increasing with T within the whole temperature range. On the other hand, the resistivity of Ca2Si is pertinent of semiconductors. Namely, it is activated below T ~ 200 K, exhibiting different slopes of ln r vs. T -1 plots at lower and higher T, and a weak increase between T ~ 200 - 300 K. Both materials demonstrate a complex dependence of R (T), including a change of the sign. Transport properties above have been analyzed assuming two groups of charge carriers, electrons and holes, contributing them.


2014 ◽  
Vol 354 ◽  
pp. 79-83
Author(s):  
Soumitra Roy ◽  
Soma Prasad ◽  
Aloke Paul

The growth of phases by reactive diffusion in Mo-Si and W-Si systems are compared. The crystal structures of MSi2 and M5Si3 phases (M = Mo, W) are similar in these two systems. However, the diffusion rates of the components change systematically with a change in the atomic number. Integrated diffusion coefficients in both phases increase with an increasing atomic number of refractory elements i.e. from Mo to W. On the other hand, the ratio of diffusivities of the components decreases. This indicates a relative increase in the diffusion rates of the metal components with increasing atomic number and a difference in defects concentrations in these two systems.


1993 ◽  
Vol 316 ◽  
Author(s):  
Hiroaki Usui ◽  
Kiyoshi Kashihara ◽  
Kuniaki Tanaka ◽  
Seizo Miyata

ABSTRACTThin films of 3,4,9,10-perylenetetracarboxylic-dianhydride (PTCDA) were deposited by an ionized beam method. The molecular orientation and chemical structure of the films were studied in connection with ionization and ion acceleration conditions. At a low ionization condition, the molecules are oriented in parallel with the substrate, and the crystallinity was improved by an appropriate ion acceleration. At higher ionization conditions, on the other hand, ion acceleration resulted in a loss of crystallinity. Deposited molecules undergo chemical change in such a condition, leading to dissociation of dianhydride groups.


2009 ◽  
pp. 67-84
Author(s):  
Marco Solimene

- The present contribution examines the rootedness of a community of xoraxané romá in the city of Rome; rather than simply the continuity of presence in a specific territory, under consideration is the development and maintenance of social networks with the Roman population, specifically in the territories romá reside and/or work in. Further on, the paper describes how rootedness may be conjugated with some forms of mobility: on the one hand, the continuity in specific areas (of work and in some cases of residence), can be maintained through practices of urban circulation; on the other hand, especially when mobility turns on national and transnational scale, the presence - although mobile and changing - of romá who belong to the same social network, spread among different territories, enables singular domestic units to maintain, despite mobility, a continuity with several non-rom realities.


2002 ◽  
Vol 748 ◽  
Author(s):  
Hiroshi Funakubo ◽  
Tomohiro Sakai ◽  
Takayuki Watanabe ◽  
Minoru Osada ◽  
Masato Kakihana ◽  
...  

ABSTRACTThin films of BIT, La-substituted BIT (BLT) and La- and V-cosubstituted BIT(BLTV) were epitaxially grown on SrRuO3//SrTiO3 substrates at 850°C by metalorganic chemical vapor deposition (MOCVD), and their electrical properties were systematically compared. All films on (100), (110) and (111)-oriented substrates were epitaxially grown with (001)-, (104)-/(014)-and (118) –preferred orientations, respectively. The leakage current density of the BLTV film was almost the same with that of the BLT film, but was smaller than that of BIT film, suggesting that the La substitution contributed to the decrease of the leakage current density especially in pseudoperovskite layer. Spontaneous polarization of the BLTV film was estimated to be almost the same with the BLT film but was smaller that that of the BIT film. This is explained by the decrease of Tc with the La substitution, while V did not contribute to the change of the Curie temperature (Tc ). On the other hand, the coercive field (Ec) value of the BLTV was smaller than that of the BIT and the BLT films. As a result, La substitution contributed to the decrease of the leakage current density together with the decrease of the spontaneous polarization due to the decrease of the Tc. On the other hand, V substitution contributes to the decrease of the defects that suppress the domain motion and increases the Ec value. Therefore, each substitution of La and V plays different roles and this contribution is remarkable for the films deposited at lower temperature.


2018 ◽  
Vol 71 (2) ◽  
pp. 142-160
Author(s):  
Jaime Gómez de Caso Zuriaga

Abstract The aim of the present contribution is twofold. On the one hand we shall discuss the background of some Islamic legends about places and wondrous objects – holy relics of the past – that had once been in the possession of the Gothic monarchy by inheritance, but were subsequently lost or looted out of al-Andalus by the Muslim leaders. On the other hand our study is concerned with the relationship between the content of the legends in question and the “loss of Spain” in a more general sense, i.e. not only the loss of these objects by the Christian Goths subsequent to their loss of power in Spain, but also their disappearance from Muslim ownership. Besides, the legends possess a moral core, which is interesting in its own right: the way in which they are viewed in the Muslim sources, the locations and objects they describe, and their relationship to the Gothic monarchy may provide the modern reader with an insight into the striking vision of the past held by the invading Muslim culture.


1976 ◽  
Vol 54 (23) ◽  
pp. 3651-3657 ◽  
Author(s):  
Fathi Habashi ◽  
Shaheer A. Mikhail

The reduction of a binary sulfate mixture cannot be predicted from the behavior of the individual components. Thus, while CuSO4 is reduced to Cu at 400 °C and NiSO4 is reduced to Ni3S2, the sulfate mixture yields Cu, Ni3S2, and Cu2S. Also while FeSO4 is completely stable in H2 at 400 °C, (Cu,Fe) SO4 yields Cu and Cu5FeS4. The formation of Cu2S in the first case and Cu5FeS4 in the second was unexpected. On the other hand, (Cu,Mn)SO4 is stable in H2 up to 550 °C although pure CuSO4 is completely reduced at 400 °C. CoSO4 also interferes when reduced in presence of CuSO4, while Na2SO4, MgSO4, Al2(SO4)3, ZnSO4, CdSO4 do not interfere within limited temperature range. Of these only Na2SO4 forms a complex sulfate with CuSO4. No Cu2SO4 was identified when CuSO4 was reduced in presence of other sulfates although it is an intermediate product during the reduction of pure CuSO4.


1999 ◽  
Vol 564 ◽  
Author(s):  
Wei-Tsu Tseng ◽  
Ying-Lang Wang

AbstractThe correlation between microstructures of Al and W metal thin films and their respective CMP performance is investigated. It is found that CMP removal rate decreases with increasing grain size. In both cases, the textures of the metal films are altered and their resistivity increased after CMP. The phenomenon is more pronounced for polish under a greater down force. The table speed, on the other hand, has only minimum effects on microstructure and resistivity. The possible underlying mechanisms leading to this phenomenon are proposed and their potential impacts on metallization reliability is discussed.


1998 ◽  
Vol 513 ◽  
Author(s):  
A. Weidinger ◽  
J. Krauser ◽  
Th. Riedle ◽  
R. Klenk ◽  
M. Ch. Lux-Steiner ◽  
...  

ABSTRACTHydrogen diffusion in CuInSe 2 single crystals and CuInS2 thin films was studied by measuring the spreading of implantation profiles upon annealing. Deep implantation with an ion energy of 10 keV and sub-surface implantation with 300 eV were applied. The diffusion coefficients in both materials were found to be in the order of 10-14 to 10-13 cm2/s in the temperature range between 400 and 520 K.These fairly low diffusivities are typical for a trap and release transport process rather than intrinsic diffusion of interstitial hydrogen. In the polycrystalline CuInS2 films, hydrogen leaves the sample through the grain boundaries.


1992 ◽  
Vol 06 (23n24) ◽  
pp. 3953-3958 ◽  
Author(s):  
Kazuyoshi Tanaka ◽  
Anvar A. Zakhidov ◽  
Kazunari Yoshizawa ◽  
Kenji Okahara ◽  
Tokio Yamabe ◽  
...  

Magnetic properties of C 60 and C 70 complexes with tetrakis(dimethylamino)ethylene (TDAE) have been studied based on the measurements of the Faraday-balance magnetization and the electron spin resonance (ESR). It has been found that both TDAE- C 60 and TDAE- C 70 possess about one radical spin per fullerene molecule. TDAE- C 60 has been confirmed to show ferromagnetic-type transition at Tc=16.7–17.5 K . Appearance of a new broad and intense ESR signal below Tc of TDAE- C 60 suggests that the radical spins in the magnetically ordered state rather localize on each C 60 molecule and are ferromagnetically correlated. On the other hand, TDAE- C 70 does not show ferromagnetism in all the temperature range down to 4.5K.


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