Concentration-Independent Solute Segregation in Laser Annealing of Semiconductor Crystals

1983 ◽  
Vol 23 ◽  
Author(s):  
Jun-ichi Chikawa ◽  
Fumio Sato ◽  
Tadasu Sunada
Keyword(s):  
Mixed Crystal ◽  
Laser Annealing ◽  
Solute Segregation ◽  
Atomic Processes ◽  
Segregation Coefficient ◽  
Depth Profiles ◽  
Semiconductor Crystals ◽  
Impurity Segregation ◽  
Solute Atoms ◽  
Interfacial Segregation

ABSTRACTAtomic processes at the interface in regrowth following laser induced melting were investigated by observing behavior of impurity segregation. The interfacial segregation coefficient k* was obtained from depth profiles of solute atoms redistributed by laser irradiation of uniformly doped Si, Ge, and GayAl1−yAs crystals. It was found that k*=k0 for B in Si, Ga in Ge ih the growth rate range of 1 m/s. It is concluded that rapid growth freezes a state of liquid monolayer adjacent to the interface which has the character of ideal solution from dilute to eutectic composition for dopant-silicon systems and in the entire range of composition for the mixed crystal.

INTERFACIAL SEGREGATION IN α-IRON

1993 ◽  
Vol 07 (01n03) ◽  
pp. 528-533 ◽  
Author(s):  
PAVEL LEJČEK
Keyword(s):  
Grain Boundaries ◽  
Alloy Composition ◽  
Solute Segregation ◽  
Silicon Nitrides ◽  
Free Surfaces ◽  
Si Model ◽  
Interfacial Segregation

Measurements of solute segregation to free surfaces and grain boundaries in well-defined samples of α-Fe-Si model alloys revealed pronounced differences. Segregation of C and P and depletion of Si are characteristic for grain boundaries. Cosegregation of Si and N resulting in formation of silicon nitrides prevails at the majority of free surfaces in samples containing nitrogen, but S segregation dominates at the surfaces of nitrogen free samples. The results are summarized from the viewpoint of the type of interface, alloy composition and segregation temperature.

scholarly journals Atom Probe Tomographic Studies of Precipitation in Al-0.1Zr-0.1Ti (at.%) Alloys

2007 ◽  
Vol 13 (6) ◽  
pp. 503-516 ◽  
Author(s):  
Keith E. Knipling ◽  
David C. Dunand ◽  
David N. Seidman
Keyword(s):  
Atom Probe Tomography ◽  
Local Thermodynamic Equilibrium ◽  
Atom Probe ◽  
Atomic Ratio ◽  
Chemical Compositions ◽  
Ti Alloys ◽  
The Matrix ◽  
Solute Atoms ◽  
Interfacial Segregation ◽  
Zr Alloys

Atom probe tomography was utilized to measure directly the chemical compositions of Al3(Zr1−xTix) precipitates with a metastable L12 structure formed in Al-0.1Zr-0.1Ti (at.%) alloys upon aging at 375°C or 425°C. The alloys exhibit an inhomogeneous distribution of Al3(Zr1−xTix) precipitates, as a result of a nonuniform dendritic distribution of solute atoms after casting. At these aging temperatures, the Zr:Ti atomic ratio in the precipitates is about 10 and 5, respectively, indicating that Ti remains mainly in solid solution rather than partitioning to the Al3(Zr1−xTix) precipitates. This is interpreted as being due to the very small diffusivity of Ti in α-Al, consistent with prior studies on Al-Sc-Ti and Al-Sc-Zr alloys, where the slower diffusing Zr and Ti atoms make up a small fraction of the Al3(Sc1−xTix/Zrx) precipitates. Unlike those alloys, however, the present Al-Zr-Ti alloys exhibit no interfacial segregation of Ti at the matrix/precipitate heterophase interface, a result that may be affected by a significant disparity in the evaporation fields of the α-Al matrix and Al3(Zr1−xTix) precipitates and/or a lack of local thermodynamic equilibrium at the interface.

Impurity segregation coefficient measurements in LiF-LuF 3 -YF 3 systems doped by Nd3+

2010 ◽  
Author(s):  
M. A. Marisov ◽  
E. Yu. Koryakina ◽  
A. K. Naumov ◽  
V. V. Semashko ◽  
S. L. Korableva ◽  
...  
Keyword(s):  
Segregation Coefficient ◽  
Impurity Segregation

Solute Trapping at a Rapidly Moving Solid/Liquid Interface for a Lennard-Jones Alloy

1989 ◽  
Vol 157 ◽  
Author(s):  
Stephen J. Cook ◽  
Paulette Clancy
Keyword(s):  
Dynamics Simulation ◽  
Segregation Coefficient ◽  
Equilibrium Conditions ◽  
Impurity Atoms ◽  
Lennard Jones ◽  
Interfacial Segregation ◽  
Non Equilibrium Molecular Dynamics ◽  
Solid Liquid Interface ◽  
Solid Liquid ◽  
Substrate Temperatures

ABSTRACTNon-equilibrium Molecular Dynamics simulation methods have been used to study the trapping of “impurities” in an Ag5B15 Lennard-Jones alloy where the B atoms are 10% bigger in diameter than A. The observation of surface melting in this system is used to calculate an equilibrium interfacial segregation coefficient. Simulations of rapid melting and resolidification were performed for the (100) and (111) orientations at two different substrate temperatures (0.65 Tm and 0.95 Tm) for each orientation. Solute impurity atoms are shown to have been trapped at greater concentrations in the solid than under equilibrium conditions. Partitionless solidification is observed when the regrowth velocity greatly exceeds the diffusive velocity.

Anomalous defect drift induced in semiconductor crystals at ion implantation and pulsed laser annealing

1988 ◽  
Vol 129 (3) ◽  
pp. 180-184 ◽  
Author(s):  
T.A. Kuzemchenko ◽  
A.A. Manenkov ◽  
G.N. Mikhailova ◽  
S.Yu. Sokolov
Keyword(s):  
Ion Implantation ◽  
Laser Annealing ◽  
Pulsed Laser ◽  
Semiconductor Crystals ◽  
Pulsed Laser Annealing

Interface Velocity and Noble Metal Segregation During Ion Beam Induced Epitaxial Crystallization

1989 ◽  
Vol 157 ◽  
Author(s):  
J. S. Custer ◽  
Michael O. Thompson ◽  
D. C. Jacobson ◽  
J. M. Poate
Keyword(s):  
Solid Phase ◽  
Ion Beam ◽  
Interface Velocity ◽  
Solid Phase Epitaxy ◽  
Segregation Coefficient ◽  
Time Resolved ◽  
Interfacial Segregation ◽  
Amorphous Si ◽  
Impurity Profiles

ABSTRACTThe interface velocity of Au and Ag doped amorphous Si during ion beam induced epitaxy was measured using in situ time resolved reflectivity. Interfacial segregation coefficients were determined as a function of composition from numerical simulations. At 320°C Au impurities enhanced the velocity by up to a factor of 2.5 compared to the intrinsic case. Silver slightly retarded re-growth by 10 %. These effects are qualitatively similar to the case of thermal solid phase epitaxy. Using the measured impurity profiles and interface velocity, computer simulations relate the segregation coefficient to the concentrations of the impurity at the interface. In both cases, the segregation coefficient increases with increasing interfacial impurity concentration.

Interfacial Segregation in Ionic Conductors: Ceria

1996 ◽  
Vol 458 ◽  
Author(s):  
D. A. Blom ◽  
Y.-M. Chiang
Keyword(s):  
Driving Forces ◽  
Boundary Segregation ◽  
Scanning Transmission Electron Microscope ◽  
Solute Segregation ◽  
Ionic Conductors ◽  
X Ray ◽  
Surface Sites ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Interfacial Segregation

ABSTRACTGrain boundary segregation in cerium dioxide doped with varying amounts of gadolinium oxide and tantalum oxide has been measured with x-ray energy dispersive spectroscopy using a Vacuum Generators HB603 Scanning Transmission Electron Microscope (STEM). The data has been analyzed in the framework of both elastic relaxation and space charge segregation forces with a limited number of surface sites. Results show that multiple driving forces must be taken into account to explain aliovalent solute segregation.

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