scholarly journals In situ TEM oxidation study of Fe thin-film transformation to single-crystal magnetite nanoparticles

2020 ◽  
Vol 55 (27) ◽  
pp. 12897-12905
Author(s):  
Leonardo Lari ◽  
Stephan Steinhauer ◽  
Vlado K. Lazarov
2010 ◽  
Vol 2010.8 (0) ◽  
pp. 263-264
Author(s):  
Taeko ANDO ◽  
Hidekazu Ishihara ◽  
Masahiro Nakajima ◽  
Shigeo Arai ◽  
Toshio Fukuda ◽  
...  

Author(s):  
M. Park ◽  
S.J. Krause ◽  
S.R. Wilson

Cu alloying in Al interconnection lines on semiconductor chips improves their resistance to electromigration and hillock growth. Excess Cu in Al can result in the formation of Cu-rich Al2Cu (θ) precipitates. These precipitates can significantly increase corrosion susceptibility due to the galvanic action between the θ-phase and the adjacent Cu-depleted matrix. The size and distribution of the θ-phase are also closely related to the film susceptibility to electromigration voiding. Thus, an important issue is the precipitation phenomena which occur during thermal device processing steps. In bulk alloys, it was found that the θ precipitates can grow via the grain boundary “collector plate mechanism” at rates far greater than allowed by volume diffusion. In a thin film, however, one might expect that the growth rate of a θ precipitate might be altered by interfacial diffusion. In this work, we report on the growth (lengthening) kinetics of the θ-phase in Al-Cu thin films as examined by in-situ isothermal aging in transmission electron microscopy (TEM).


1994 ◽  
Vol 364 ◽  
Author(s):  
A. Korner

AbstractThe domain structure and the evolution of antiphase boundaries (APBs) have been investigated in Fe-Al by means of “in-situ” transmission electron microscopy (TEM) heating experiments. Single crystals with composition Fe22.1at%Al and Fe25.6at%Al have been used.The grown-in structure of the Fe22.1at%al single crystal is composed of DO3 ordered particles embedded in the disorderd ±-matrix. A bimodal distribution of the particles was found. Small ordered particles are in between the large precipitates which are surrounded by particle-free zones. Numerous of this large ordered precipitates contain APBs. Crossing the transition temperature to the disordered phase, the small particles dissolve into the ±-matrix and the large particles start to shrink by dissolving.The single crystal with composition Fe25.6at%Al was found to be completely DO3 ordered. The grown-in domains are separated by APBs of type a′0/2〈100〉. At temperatures far below the transition temperature to the B2 phase no significant change in the APB and domain structure has been detected. In contrast, a remarkable evolution in the APB structure has been observed approaching the transition temperature. Coarsening of the domains has been found. Furthermore, APBs of B2-type (a′0/4〈lll〉 shear) are dragged out by dislocation motion. B2- and DC3-type APBs react and junctions are formed. With increasing annealing time, the density of B2-type boundaries increases. The TEM image is dominated by B2-type boundaries linked by the D03-type boundaries. The DO3 superlattice spots are clearly excited approaching the transition temperature to B2. Above the transition temperature, the DO3 spots disappear completely and the diffraction pattern reveals B2 long range order.


1992 ◽  
Vol 275 ◽  
Author(s):  
M. Powers ◽  
R. Gronsky ◽  
J. Washburn

ABSTRACTA technique is presented where Ag is initially sputter deposited on a single crystal ceramic substrate followed by in situ deposition of YBa2Cu3O7δ The resulting microstructure shows Ag islands amidst a c-axis oriented YBCO film, apparently with intimate contact between the YBCO and substrate. This morphology appears ideal for electrical contact to the {hko} surfaces of the superconductor with current carrying CuO planes in maximum contact with the Ag.


2002 ◽  
Vol 751 ◽  
Author(s):  
Manabu Ohkubo ◽  
Kumiko Fukai ◽  
Kohji Matsuo ◽  
Nobuyuki Iwata ◽  
Hiroshi Yamamoto

ABSTRACTThe Re oxide films were deposited on quartz glasses by RF reactive sputtering from a Re metal target. The lowest resistivity was observed in the film in-situ annealed at 200?C in Ar atmosphere and showed the order of 10-4 Ωcm of which the value was still about 10 times as large as that of a single crystal ReO3. The temperature dependence of the resistivity revealed a metallic behavior. A superconductivity did not take place in the bilayered film of ReO3 / NdBa2Cu3O6. In the interface region the resistivity minimum probably caused by the Kondo effect was observed in the neighborhood of 120K.


1996 ◽  
Vol 441 ◽  
Author(s):  
K. Tsujimoto ◽  
S. Tsuji ◽  
H. Saka ◽  
K. Kuroda ◽  
H. Takatsuji ◽  
...  

AbstractThe recent attention paid to stress migration of aluminum (Al) electrodes in thin-film transistor liquid crystal display (TFT-LCD) applications indicates that wiring materials with low electrical resistivities are of considerable interest for their potential use in higher-resolution displays. In this paper, we firstly describe how as-grown Al whiskers on Al electrodes fabricated on a LCD-grade glass substrate can be characterized by means of a high-voltage transmission electron microscope (HV-TEM) operated at 1 MV. The whiskers ranging from 300 to 400 nm in diameter are sufficient to be transparent to high-voltage electrons. This allows detailed observation of whisker characteristics such as its morphology and crystallography. In most cases, the as-grown Al whiskers in our study had straight rod shapes, and could be regarded as single crystals. Secondly, we report on the in-situ fabrication and observation of Al whiskers at elevated temperature with the HV-TEM. Since relatively thick TEM samples (up to about 1 mm) can be set on a sample holder in the HV-TEM, various growth stages of Al whiskers can be investigated under various heating conditions. Finally, we demonstrate a TEM sample preparation method for the cross-section of an individual Al whisker, using focused ion beam (FIB) etching. This technique makes it possible to reduce the thickness of an Al whisker close to the root. Both bright- and dark-field TEM images provide nanostructural information on the whisker/Al thin-film interface.


2019 ◽  
Vol 377 ◽  
pp. 124878
Author(s):  
J. Drieu La Rochelle ◽  
P. Godard ◽  
C. Mocuta ◽  
D. Thiaudière ◽  
J. Nicolai ◽  
...  

Author(s):  
T.T. Chung ◽  
J. Dash ◽  
R.J. O'Brien

The electron microscope is an important instrument for studying the structure and morphology of particulates collected from the atmosphere, but its potential for direct observation of the interactions between atmospheric aerosols and gases has not been explored previously. A cell with thin film windows and ports to permit the passage of gases was constructed for this purpose, Fig. 1. This cell is designed for use in the tilting stage of a Hitachi HU125 TEM. The thin film windows (manufactured by E. F. Full am, Inc. (1) ) consist of a composite film of formvar and evaporated SiO on 400 mesh Cu grids.In the first experiments with this cell, particles of NaCl were collected from a modified De Vilbiss nebulizer on the lower window of the cell and observed continuously during passage through the cell of either (1) water vapor or (2) water vapor and NO2.The image was recorded continuously on video tape and intermittently on sheet film.


2010 ◽  
Vol 241 ◽  
pp. 012060 ◽  
Author(s):  
P Landau ◽  
R Z Shneck ◽  
G Makov ◽  
A Venkert
Keyword(s):  

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