Growth Kinetics of an Amorphous Phase Between GaAs and Co

1991 ◽  
Vol 230 ◽  
Author(s):  
F. Y. Shiau ◽  
Y. A. Chang
Keyword(s):  
Amorphous Phase ◽  
Growth Kinetics ◽  
Electron Spectroscopy ◽  
Supersaturated Solid Solution ◽  
Parabolic Rate Constant ◽  
Transmission Electron ◽  
Gaas Structure ◽  
Approximate Composition ◽  
Kinetics Of ◽  
State Amorphization

AbstractSolid-state amorphization reaction between GaAs and Co thin-films was investigated by transmission electron micorscopy and Auger electron spectroscopy. Upon annealing of GaAs/Co thin-film couples at 260–300 °C, an amorphous phase was observed to form. The amorphization was attributed to the openness of the GaAs structure relative to the size of the Co atoms. This allows rapid diffusion of Co into the GaAs lattice and promotes the occurrence of SSAR. Annealing at higher temperatures or for longer times led to the formation of a crystalline phase, designated as the μ-phase which was determined to be a metastable supersaturated solid solution of CoAs exhibiting the B31 structure of the approximate composition of Co(Ga. .48As.52). The growth kinetics of both the amorphous phase and the μ-phase are parabolic in nature. The parabolic rate constant is higher for the μ-phase than for the amorphous phase. The activation energies are 1.47 and 1.35 eV, respectively.

Growth Kinetics Of SiO2 On (001)Si Catalyzed By Cu3Si At Elevated Temperatures

1999 ◽  
Vol 564 ◽  
Author(s):  
H. Y. Huang ◽  
L. J. Chen
Keyword(s):  
Growth Rate ◽  
Growth Kinetics ◽  
Electron Spectroscopy ◽  
Auger Electron ◽  
Linear Growth ◽  
Elevated Temperatures ◽  
The Other ◽  
Wet Oxidation ◽  
Transmission Electron ◽  
Kinetics Of

AbstractThe oxidation of Si catalyzed by 170-nm-thick Cu3Si at elevated temperatures has been investigated by transmission electron microscopy and Auger electron spectroscopy. For wet oxidation at 140–180 °C, the growth rate of the oxide layer was increased with the temperature. On the other hand, as the temperature was increased above 200 °C, the growth rate slowed down. The growth kinetics of oxide was investigated. Controlling mechanisms for the growth of oxide owing to the grain growth of Cu3Si are discussed. The activation energy for the linear growth of oxide was measured to be 0. 19 ± 0.1 eV.

Formation and growth of an amorphous phase by solid-state reaction between GaAs and Co thin films

1991 ◽  
Vol 6 (7) ◽  
pp. 1532-1541 ◽  
Author(s):  
F-Y. Shiau ◽  
S-L. Chen ◽  
M. Loomans ◽  
Y.A. Chang
Keyword(s):  
Thin Films ◽  
Solid State ◽  
Amorphous Phase ◽  
Solid Solution Phase ◽  
Pseudobinary System ◽  
Transmission Electron ◽  
Gaas Structure ◽  
Thermodynamic Driving Force ◽  
Stability Data ◽  
State Amorphization

Solid-state amorphization reaction (SSAR) between GaAs and Co thin films was investigated by transmission electron microscopy and Auger electron spectroscopy. Upon annealing of GaAs/Co thin-film couples at 260–300 °C, an amorphous phase was observed to form. Annealing at higher temperatures or for longer times led to the crystallization of the amorphous phase into a supersaturated CoAs solid solution phase with the B31 structure. Amorphization is attributed to the rapid diffusion of Co in the rather open GaAs structure. In order to consider the thermodynamic driving force for amorphization and subsequent crystallization, the phase diagram of CoGa–CoAs was investigated using DTA and metallography. The pseudobinary system was modeled thermodynamically to yield relative stability data for the various phases between GaAs and Co. These data were used to rationalize the amorphization process.

Growth kinetics of CoSi2 and Ge islands observed with in situ transmission electron microscopy

Micron ◽  
1999 ◽  
Vol 30 (1) ◽  
pp. 21-32 ◽  
Author(s):  
F.M. Ross ◽  
P.A. Bennett ◽  
R.M. Tromp ◽  
J. Tersoff ◽  
M. Reuter
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Growth Kinetics ◽  
Transmission Electron ◽  
Kinetics Of

Growth Kinetics of Interfacial Intermetallic Compound in Al(AA4343)/Steel(SUS316) Clad Strip

2020 ◽  
Vol 993 ◽  
pp. 447-456
Author(s):  
Xiao Jun Zhang ◽  
Kun Yuan Gao ◽  
Xiu Hua Hu ◽  
Yu Sheng Ding ◽  
Guo Zhan Wang ◽  
...  
Keyword(s):  
Growth Kinetics ◽  
Annealing Temperature ◽  
Optical Microscope ◽  
Alloy Layer ◽  
Kinetics Analysis ◽  
Growth Constant ◽  
Transmission Electron ◽  
Dispersive System ◽  
The Relationship ◽  
Kinetics Of

The composition and microstructure of intermetallic compounds (IMC) at the interface of aluminum(AA4343)-stainless steel(SUS316) were studied upon annealing at 550°C for 1h to 20h and at 610°C for 15min to 10h by means of optical microscope(OM) , scanning electron microscope (SEM) with energy dispersive system(EDS) and transmission Electron Microscopy (TEM). The results showed that the IMC was of 4.3μm to 36.1μm thick during heat treatment at 550°C for 1h to 20h, and the IMC contained Al-Fe-Si-Cr-Ni-Mo and Al-Fe-Si -Ni. During annealing at 610°C for 15min to 5h, the thickness of IMC was 31.2 μm to 208 μm, and the IMC were mainly of η-Fe2Al5 and τ10- Al4Fe1.7Si at 550°C for 10h. As the annealing time extended to 10h, natural delamination occurred at the interface between the aluminum alloy layer and IMC layer. The growth kinetics analysis showed that the relationship between the thickness of IMC “X” and time “t” followed the relational equation X=(kt)n. For AA4343(solid) - SUS316(solid), n was 1/2, and the growth constant k = 1.9×10-13m2/s at annealing temperature of 550 °C. When the temperature was 610°C, AA4343 - SUS316 was a liquid-solid contact reaction, n was 1, the growth constant k=1.45×10-8m/s.

scholarly journals Growth Kinetics of the Selected Intermetallic Phases in Ni/Al/Ni System with Various Nickel Substrate Microstructure

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 134 ◽  
Author(s):  
Izabella Kwiecien ◽  
Piotr Bobrowski ◽  
Anna Wierzbicka-Miernik ◽  
Lidia Litynska-Dobrzynska ◽  
Joanna Wojewoda-Budka
Keyword(s):  
Electron Microscopy ◽  
Growth Kinetics ◽  
Intermetallic Phases ◽  
Nickel Aluminum ◽  
Nickel Substrate ◽  
Electron Backscattered Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Nickel Substrates ◽  
Kinetics Of

Reactivity in nickel–aluminum system was examined for two variants of nickel substrates in terms of the size and shape of Ni grains. The microstructure transformation aroused due to the annealing at 720 °C for different annealing times (0.25 to 72 h) was consequently followed. The sequence of formation of the particular intermetallic phases was given. The interconnection zones were examined by means of scanning electron microscopy supported with energy dispersive X-ray spectroscopy and electron backscattered diffraction techniques as well as by the transmission electron microscopy. The growth kinetics data for AlNi, AlNiNi-rich and AlNi3 phases for both variants of substrates was given, indicating the differences obtained in previous works on this subject.

Growth kinetics of MgB2 layer and interfacial MgO layer during ex situ annealing of amorphous boron film

2004 ◽  
Vol 19 (10) ◽  
pp. 3081-3089 ◽  
Author(s):  
Hyun-Mi Kim ◽  
Sung-Soo Yim ◽  
Ki-Bum Kim ◽  
Seung-Hyun Moon ◽  
Young-Woon Kim ◽  
...  
Keyword(s):  
Growth Kinetics ◽  
Interfacial Layer ◽  
Surface Reaction ◽  
Layer Growth ◽  
Ex Situ ◽  
Amorphous Boron ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Kinetics Of ◽  
Rough Surface Morphology

This paper describes the growth kinetics of an interfacial MgO layer as well as those of an MgB2 layer during ex situ annealing of the evaporated amorphous boron (a-B) film under Mg vapor overpressure. A thin MgO layer is formed at the interface between a-B and Al2O3 substrate before the formation of crystalline MgB2 layer and the interfacial layer is epitaxially related with Al2O3 substrate (MgO (111)[110] // Al2O3 (0001)[1100]). The interfacial MgO layer continues to grow during the annealing, and its apparent growth rate is about 0.1 nm/min. The analysis of MgB2 layer growth kinetics using cross-sectional transmission electron microscopy reveals that there exist two distinct growth fronts at both sides of an MgB2 layer. The growth kinetics of the lower MgB2 layer obeys the parabolic rate law during the entire annealing time. The growth of the upper MgB2 layer is controlled by the surface reaction between out-diffused boron and Mg vapor up to 10 min, resulting in a rough surface morphology of MgB2 layer. By considering the mass balance of Mg and boron during ex situ annealing, we obtained the diffusivities of Mg and boron in MgB2 layer which were in the same order range of approximately 10−12 cm2/s.

Spinodal Decomposition in Fe-Cr Alloys

2011 ◽  
Vol 172-174 ◽  
pp. 443-448
Author(s):  
Orlando Soriano Vargas ◽  
Erika O. Avila Davila ◽  
Victor M. Lopez-Hirata ◽  
Maribel L. Saucedo-Muñoz
Keyword(s):  
Solid Solution ◽  
Mechanical Behavior ◽  
Spinodal Decomposition ◽  
Growth Kinetics ◽  
Supersaturated Solid Solution ◽  
Rich Phase ◽  
Hardening Behavior ◽  
Plate Shape ◽  
Kinetics Of ◽  
Preferential Alignment

The hardening behavior of precipitation was studied during aging of Fe-Cr alloys. This mechanical behavior is associated with the nanometric modulation structure of the coherent decomposed Fe-rich and Cr-rich phases formed by the spinodal decomposition of the supersaturated solid solution. The growth kinetics of spinodal decomposition was very slow and it increased during coarsening stage. The morphology of decomposed phases consisted of an interconnected irregular shape with no preferential alignment for short aging times and a further aging caused the change to a plate shape of the decomposed Cr-rich phase aligned in the <110> directions of the Fe-rich matrix. The rapid increase in hardness and embrittlement seem to be associated with the coherency and nanometer size of the spinodally-decomposed phases in the aged alloys.

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