Growth of thin, crystalline oxide, nitride, and oxynitride films on NiAl and CoGa surfaces

1997 ◽  
Vol 65 (6) ◽  
pp. 551-566 ◽  
Author(s):  
R. Franchy ◽  
G. Schmitz ◽  
P. Gassmann ◽  
F. Bartolucci
Keyword(s):  
Crystalline Oxide

13.3-inch 8k4k 664-ppi foldable OLED display using crystalline oxide semiconductor FETs

2015 ◽  
Vol 23 (12) ◽  
pp. 600-606 ◽  
Author(s):  
Kei Takahashi ◽  
Takehisa Sato ◽  
Roh Yamamoto ◽  
Hideaki Shishido ◽  
Toshiyuki Isa ◽  
...  
Keyword(s):  
Oxide Semiconductor ◽  
Crystalline Oxide ◽  
Oled Display

Melt Quality Assessment

2019 ◽  
Author(s):  
Derya Dispinar
Keyword(s):  
Aluminum Oxide ◽  
Die Casting ◽  
Liquid Aluminum ◽  
Hydrogen Gas ◽  
Optimized Design ◽  
Hydrogen Atoms ◽  
Reduced Pressure ◽  
Cast Part ◽  
Crystalline Oxide ◽  
Pressure Die Casting

It is well known that the reaction of liquid aluminum with the moisture in the environment results in two products: aluminum oxide and hydrogen gas that dissolves in aluminum. Both of these products are considered to be detrimental to the properties of aluminum alloys. Therefore, test equipment has been developed to check the levels of these defects in the melt. Many of these involve expensive and consumable tools. In addition, an experienced personnel may be required to interpret the results. Nonetheless, aluminum oxide is harmless as long as it remains on the surface. The problem begins when this oxide is entrained into the liquid aluminum such as turbulence during transfer or mold filling in a non-optimized design. This can only happen by folding of the oxide. During this action, rough surface of the oxides comes in contact to form no bonds. These defects are known as bifilms that have certain characteristics. First, they act as cracks in the cast parts since they are oxides. It is important to note that aluminum oxide has thin amorphous oxide (known as young oxides) and thick crystalline oxide (γ-Al2O3) that may be formed in a casting operation. Second, almost zero force is required to open these bifilms due to the unbonded folded oxide skins. Thus, these defects can easily form porosity by unravelling during solidification shrinkage. On the other hand, the formation of porosity by hydrogen is practically impossible. Theoretically, hydrogen has high solubility in the liquid but it has significantly low solubility in solid aluminum. Thus, it is suspected that hydrogen is rejected from the solidification front to form hydrogen gas and porosity. However, the hydrogen atom has the smallest atomic radii and high diffusibility. Therefore, segregation of hydrogen in front of the growing solid is difficult. In addition, the energy required for hydrogen atoms to segregate and form hydrogen gas molecule is around 30,000 atm. Under these conditions, porosity formation by hydrogen is not likely to be achieved. Hydrogen probably stays in a supersaturated state or diffuses homogeneously through the cast part. The effect of hydrogen can only be seen when it can diffuse into the unbonded gap between the bifilms to open them up to aid the unravelling of bifilms to form porosity. This phenomenon can be easily detected by a very simple test called reduced pressure test. When a sample is solidified under vacuum, the bifilms start to open up. Since all porosity is formed by bifilms, the cross section of the sample solidified under vacuum can be analyzed by means of image analysis software. The sum of maximum length of pores can be measured as an indication of melt quality. Since bifilms are the most detrimental defects, this value is called “bifilm index” given in millimetres, which makes this test the only test that can quantify aluminum melt quality in such detail including both the effects of bifilms and hydrogen together. Several Al-Si alloys were used at various conditions: degassing with lance, ceramic diffusers, and graphite rotary has been compared. Gravity sand casting, die casting, and low-pressure die casting methods were evaluated. The effect of grain refiners and modifiers was studied. And the evolution of the bifilm index has been presented.

scholarly journals Third-order nonlinear optical susceptibility of crystalline oxide yttria-stabilized zirconia

2020 ◽  
Vol 8 (2) ◽  
pp. 110 ◽  
Author(s):  
Guillaume Marcaud ◽  
Samuel Serna ◽  
Karamanis Panaghiotis ◽  
Carlos Alonso-Ramos ◽  
Xavier Le Roux ◽  
...  
Keyword(s):  
Nonlinear Optical ◽  
Yttria Stabilized Zirconia ◽  
Stabilized Zirconia ◽  
Third Order ◽  
Nonlinear Optical Susceptibility ◽  
Optical Susceptibility ◽  
Crystalline Oxide

Embedded SRAM and Cortex-M0 core with backup circuits using a 60-nm crystalline oxide semiconductor for power gating

2014 ◽  
Author(s):  
Hikaru Tamura ◽  
Kiyoshi Kato ◽  
Takahiko Ishizu ◽  
Tatsuya Onuki ◽  
Wataru Uesugi ◽  
...  
Keyword(s):  
Oxide Semiconductor ◽  
Power Gating ◽  
Crystalline Oxide ◽  
Embedded Sram

Numerical Simulations on the Growth of Thin Oxide Films on Aluminum Substrates

2010 ◽  
Vol 297-301 ◽  
pp. 954-959 ◽  
Author(s):  
Aurelien Perron ◽  
Sébastien Garruchet ◽  
Olivier Politano ◽  
G. Aral ◽  
Vincent Vignal
Keyword(s):  
Chemical Composition ◽  
Oxygen Pressure ◽  
Oxide Films ◽  
Oxidation Kinetic ◽  
Degree Of Crystallinity ◽  
Crystalline Oxide ◽  
Thin Oxide Films ◽  
Nanocrystalline Aluminum ◽  
Aluminum Substrates ◽  
Aluminum Surfaces

We investigated the oxidation of nanocrystalline aluminum surfaces by using variable charge molecular dynamics at 600 K under three oxygen pressures: 1, 10 and 20 atm. The interaction potential was described by the electrostatic plus (Es+) model that allows dynamical charge transfer among atoms. We mainly focused on the effect of the oxygen pressure on the oxidation kinetic, the chemical composition and the microstructure of the oxide films formed. The results show that oxidation kinetics as well as chemical composition and microstructure depend on the applied oxygen pressure. The oxide film thickness tends to a limiting value equal to ~3 nm. Finally, we obtained a partially crystalline oxide films for all oxygen pressures and we observed that the degree of crystallinity increases with time.

The Structure of the (001)Si/SiO2 Interface

1987 ◽  
Vol 105 ◽  
Author(s):  
A. Ourmazd ◽  
J. Bevk
Keyword(s):  
Electron Diffraction ◽  
Structural Data ◽  
Bulk Phase ◽  
Careful Examination ◽  
Imaging Data ◽  
Lattice Imaging ◽  
Crystalline Layer ◽  
Crystalline Oxide ◽  
Lattice Images

AbstractWe show that a careful examination of previous microscopic structural data from the Si/SiO2 interface reveals that the presence of an epitaxial interfacial oxide cannot be ruled out, and describe the conditions necessary for a definitive search for an intervening layer between c-Si and a-SiO2 We present electron diffraction and lattice imaging data, which establish the c-Si→a-SiO2 transition to take place via a crystalline layer ˜7 A thick. Modelling of lattice images in two projections indicates the crystalline oxide to be tridymite, a stable, bulk phase of SiO2

Freestanding crystalline oxide perovskites down to the monolayer limit

Nature ◽  
2019 ◽  
Vol 570 (7759) ◽  
pp. 87-90 ◽  
Author(s):  
Dianxiang Ji ◽  
Songhua Cai ◽  
Tula R. Paudel ◽  
Haoying Sun ◽  
Chunchen Zhang ◽  
...  
Keyword(s):  
Crystalline Oxide

Preparation of YBa2Cu3O7-δ -Coated Conductor on Single Crystalline Oxide Fiber by Hot-Wall MOCVD

1998 ◽  
pp. 623-626
Author(s):  
Masato Hasegawa ◽  
Yutaka Yoshida ◽  
Yoshiaki Ito ◽  
Morihiro Iwata ◽  
Junichi Kawashima ◽  
...  
Keyword(s):  
Coated Conductor ◽  
Single Crystalline ◽  
Oxide Fiber ◽  
Crystalline Oxide

Epitaxial (001) Ge on Crystalline Oxide Grown on (001) Si

2008 ◽  
pp. 119-122
Author(s):  
Ch Dieker ◽  
J W Seo ◽  
A Guiller ◽  
M Sousa ◽  
J-P Locquet ◽  
...  
Keyword(s):  
Crystalline Oxide
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