Correlation between surface step structure and phase separation in epitaxial GaInAsSb

2000 ◽  
Vol 76 (15) ◽  
pp. 2077-2079 ◽  
Author(s):  
C. A. Wang
Keyword(s):  
Phase Separation ◽  
Surface Step ◽  
Step Structure

Correlation Between GaInAsSb Surface Step Structure and Phase Separation

1999 ◽  
Vol 607 ◽  
Author(s):  
C.A. WANG
Keyword(s):  
Phase Separation ◽  
Quantitative Measure ◽  
Organometallic Vapor Phase Epitaxy ◽  
Full Width ◽  
Vicinal Surface ◽  
Lower Growth ◽  
Surface Step ◽  
Step Structure ◽  
Peak Energy ◽  
Lower Growth Temperature

AbstractA strong correlation between the surface step structure and phase separation in metastable GaInAsSb epitaxial layers grown by organometallic vapor phase epitaxy has been identified. The full width at half maximum (FWHM) of 4-K photoluminescence (PL) peak energy is used as a semi-quantitative measure of the degree of phase separation. The step structure of GaInAsSb grown at 525 °C is vicinal, while it is step-bunched for layers grown at 575 °C. The corresponding 4-K PL FWHM data indicate that the degree of phase separation is minimized when the layers aregrown at the lower growth temperature. It is proposed that the longer terrace lengths of a step-bunched surface are associated with a longer adatom lifetime compared to a vicinal surface, and thus the adatoms have more time to cluster and phase separate, which is the preferred equilibrium state. Increasing the growth rate, which reduces the adatom lifetime, also reduces the PL FWHM, and thus, the degree of phase separation.

Surface step structure of a lens-shaped Si(001) vicinal substrate

1989 ◽  
Vol 183 (1-2) ◽  
pp. 229-233 ◽  
Author(s):  
Kunihiro Sakamoto ◽  
Kazushi Miki ◽  
Tsunenori Sakamoto
Keyword(s):  
Surface Step ◽  
Step Structure ◽  
Vicinal Substrate

Isoelectronic surfactant-induced surface step structure and correlation with ordering in GaInP

2002 ◽  
Vol 235 (1-4) ◽  
pp. 15-24 ◽  
Author(s):  
S.W. Jun ◽  
G.B. Stringfellow ◽  
J.K. Shurtleff ◽  
R.-T. Lee
Keyword(s):  
Surface Step ◽  
Step Structure

scholarly journals Surface Evolution of 4H-SiC(0001) during In Situ Surface Preparation and its Influence on Graphene Properties

2013 ◽  
Vol 740-742 ◽  
pp. 157-160 ◽  
Author(s):  
Jawad ul Hassan ◽  
Axel Meyer ◽  
Semih Cakmakyapan ◽  
Ozgur Kazar ◽  
Jan Ingo Flege ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Growth Process ◽  
Substrate Surface ◽  
Surface Preparation ◽  
Surface Evolution ◽  
Surface Step ◽  
Graphene Growth ◽  
Graphene Layers ◽  
Step Structure

The evolution of SiC surface morphology during graphene growth process has been studied through the comparison of substrate surface step structure after in-situ etching and graphene growth in vacuum. Influence of in-situ substrate surface preparation on the properties of graphene was studied through the comparison of graphene layers on etched and un-etched substrates grown under same conditions.

Surface step structure of Ag13OsO6, experimental evidence for Ag13cluster building blocks

2004 ◽  
pp. 462-463 ◽  
Author(s):  
Sascha Ahlert ◽  
Lars Diekhöner ◽  
Roman Sordan ◽  
Klaus Kern ◽  
Martin Jansen
Keyword(s):  
Experimental Evidence ◽  
Building Blocks ◽  
Surface Step ◽  
Step Structure

SURFACE STEP STRUCTURE OF A LENS-SHAPED Si(001) VICINAL SUBSTRATE

1989 ◽  
pp. 229-233
Author(s):  
KUNIHIRO SAKAMOTO ◽  
KAZUSHI MIKI ◽  
TSUNENORI SAKAMOTO
Keyword(s):  
Surface Step ◽  
Step Structure ◽  
Vicinal Substrate

Surface Step Structure of Ag13OsO6, Experimental Evidence for Ag13 Cluster Building Blocks.

ChemInform ◽  
2004 ◽  
Vol 35 (18) ◽  
Author(s):  
Sascha Ahlert ◽  
Lars Diekhoener ◽  
Roman Sordan ◽  
Klaus Kern ◽  
Martin Jansen
Keyword(s):  
Experimental Evidence ◽  
Building Blocks ◽  
Surface Step ◽  
Step Structure

Bulk standards for low-temperature biological x-ray microanalysis

1984 ◽  
Vol 42 ◽  
pp. 282-283
Author(s):  
P. Echlin ◽  
M. McKoon ◽  
E.S. Taylor ◽  
C.E. Thomas ◽  
K.L. Maloney ◽  
...  
Keyword(s):  
Phase Separation ◽  
Low Temperature ◽  
Analytical Method ◽  
Salt Solutions ◽  
Absolute Concentration ◽  
Cooling Process ◽  
X Ray ◽  
The Absolute ◽  
Analytical Procedures ◽  
Electrical Conductors

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.

Decoration technique and surface physics

1978 ◽  
Vol 36 (1) ◽  
pp. 436-437 ◽  
Author(s):  
H. Bethge
Keyword(s):  
Diffusion Path ◽  
Special Importance ◽  
Surface Physics ◽  
Step Structure ◽  
Initial Stage ◽  
Special Cases ◽  
Atomic Surface ◽  
The Mean ◽  
Bulk Structure ◽  
Decoration Technique

Besides the atomic surface structure, diverging in special cases with respect to the bulk structure, the real structure of a surface Is determined by the step structure. Using the decoration technique /1/ it is possible to image step structures having step heights down to a single lattice plane distance electron-microscopically. For a number of problems the knowledge of the monatomic step structures is important, because numerous problems of surface physics are directly connected with processes taking place at these steps, e.g. crystal growth or evaporation, sorption and nucleatlon as initial stage of overgrowth of thin films.To demonstrate the decoration technique by means of evaporation of heavy metals Fig. 1 from our former investigations shows the monatomic step structure of an evaporated NaCI crystal. of special Importance Is the detection of the movement of steps during the growth or evaporation of a crystal. From the velocity of a step fundamental quantities for the molecular processes can be determined, e.g. the mean free diffusion path of molecules.

Phase separation in sol gel-derived ceramic films of silica-zirconia, alumina-zirconia, and titania-zirconia system

1994 ◽  
Vol 52 ◽  
pp. 646-647
Author(s):  
J. Tong ◽  
L. Eyring
Keyword(s):  
Fracture Toughness ◽  
Phase Separation ◽  
Sol Gel ◽  
Great Influence ◽  
High Strength ◽  
Chemical Durability ◽  
Separation Method ◽  
Toughening Mechanism ◽  
Ceramic Films ◽  
Zirconia Toughened Alumina

There is increasing interest in composites containing zirconia because of their high strength, fracture toughness, and its great influence on the chemical durability in glass. For the zirconia-silica system, monolithic glasses, fibers and coatings have been obtained. There is currently a great interest in designing zirconia-toughened alumina including exploration of the processing methods and the toughening mechanism.The possibility of forming nanocrystal composites by a phase separation method has been investigated in three systems: zirconia-alumina, zirconia-silica and zirconia-titania using HREM. The morphological observations initially suggest that the formation of nanocrystal composites by a phase separation method is possible in the zirconia-alumina and zirconia-silica systems, but impossible in the zirconia-titania system. The separation-produced grain size in silica-zirconia system is around 5 nm and is more uniform than that in the alumina-zirconia system in which the sizes of the small polyhedron grains are around 10 nm. In the titania-zirconia system, there is no obvious separation as was observed in die alumina-zirconia and silica-zirconia system.

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