Influence of small-cluster mobility on the island formation in molecular beam epitaxy

2000 ◽  
Vol 62 (11) ◽  
pp. 7545-7552 ◽  
Author(s):  
Sang Bub Lee ◽  
Bikash C. Gupta
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Small Cluster ◽  
Island Formation

The Effect of Deposition Method on Growth Morphology - Comparison of Molecular Beam Epitaxy, Ion Beam Assisted Deposition and Sputter Deposition

1998 ◽  
Vol 528 ◽  
Author(s):  
Th. Michely ◽  
M. Kalff ◽  
G. Comsa
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Ion Beam ◽  
Growth Front ◽  
Film Structure ◽  
Sputter Deposition ◽  
Formation Mechanisms ◽  
Island Formation ◽  
Ion Beam Assisted Deposition ◽  
Film Roughness

AbstractThin films created by the deposition or under influence of atoms with hyperthermal energies (E = 100 -104eV) exhibit properties which differ in many respects from those of films created by deposition of atoms with thermal energy. The morphologies of thin Pt-films deposited on Pt(111) under otherwise identical deposition conditions by molecular beam epitaxy (MBE), ion beam assisted deposition (IBAD) and sputter deposition (SD) differ in film structure size, island shapes and film roughness. The different film structure sizes are unambiguously traced back to two different island formation mechanisms inherent to these deposition methods. While in MBE the islands result from nucleation in a supersaturated adatom gas, in IBAD and SD they result by direct or indirect creation of adatom clusters as a consequence of single impacts of energetic atoms present in the depositing particle flux. The differences in film roughness are not only due to the different island formation mechanisms, but seem to be closely related to the different step edge structures at the growth front.

THE STUDIES OF THERMAL ANNEALING ON Pt/AlGaN GROWN ON Si(111) BY PLASMA-ASSISTED MOLECULAR BEAM EPITAXY (PA-MBE)

2010 ◽  
Vol 24 (29) ◽  
pp. 2889-2898 ◽  
Author(s):  
M. Z. MOHD YUSOFF ◽  
Z. HASSAN ◽  
C. W. CHIN ◽  
S. M. THAHAB ◽  
H. ABU HASSAN
Keyword(s):  
Electron Microscopy ◽  
Molecular Beam Epitaxy ◽  
Barrier Height ◽  
Thermal Annealing ◽  
Ideality Factor ◽  
Molecular Beam ◽  
Annealing Temperature ◽  
Sem Analysis ◽  
Metal Contacts ◽  
Island Formation

The application of thermal annealing at various annealing temperatures (473–1073 K) has been shown to significantly modify surface morphology of platinum ( Pt ) metal contacts on AlGaN / GaN / AlN heterostructure grown on silicon by plasma-assisted molecular beam epitaxy (PA-MBE). Structural analysis of the AlGaN / GaN samples used for the Pt Schottky contacts fabrication were performed by using high resolution X-ray diffraction (HR-XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Pt metal contacts were then deposited on the samples followed by current–voltage (I–V) characterization. Thermally-treated samples showed significant decrease in current compared with untreated samples. From the I–V measurements, the Schottky barrier height (SBH) and ideality factor (n) were calculated. We found that the lowest value of SBH obtained was 0.526 eV at 873 K annealing temperature. Unfortunately, there are no values for the SBH and ideality factor at 1073 K annealing temperature. The SEM analysis has shown some island formation at high annealing temperature due to the difference of surface energies between thin metal films and AlGaN that causes dewetting. We suggest that the reason for the barrier height reduction is due to the metal island formation on the samples.

Defect and Island Formation in Stranski-Krastanov Growth of Ge on Si (001)

1993 ◽  
Vol 317 ◽  
Author(s):  
Akira Sakai ◽  
Toru Tatsumi
Keyword(s):  
Molecular Beam Epitaxy ◽  
High Temperatures ◽  
Molecular Beam ◽  
Island Formation ◽  
Nucleation Mode

ABSTRACTWe have examined macroscopic island (Macro-island) formation in Stranski-Krastanov (SK) growth of Ge on Si (001) surfaces at various growth temperatures in molecular beam epitaxy (MBE). The nucleation mode of Macro-island formation was observed to be predominantly heterogeneous at medium growth temperatures less than 450°C, but homogeneous at high temperatures. In the heterogeneous Mode, Macro-island formation is mediated by particular V-shaped defects running preferentially along the <110> direction, which form as a result of coalescence of the well-faceted islands.

Heteroepitaxy of Si and Ge on CaF2/Si (111)

1985 ◽  
Vol 54 ◽  
Author(s):  
R. W. Fathauer ◽  
L. J. Schowalter ◽  
N. Lewis ◽  
E. L. Hall
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Qualitative Model ◽  
Island Growth ◽  
Island Formation ◽  
Growth Studies ◽  
Si Epitaxy

ABSTRACTSi and Ge layers have been grown on CaF /Si (111) by molecular beam epitaxy (MBE). The use of thin room-tempe rature predeposits [1] with Ge epitaxy has been found to improve the growth. Studies of the initial stages of Ge epitaxy indicate that island growth occurs, and evidence also indicates island formation occurs in the Si case as well. A qualitative model is presented which explains many of the features observed in these systems and suggests reasons for the superior growth of Ge compared to Si. Finally, use of a Ge Si, /Si superlattice is shown to improve Si epitaxy.

Suppression of Island Formation During Initial Stages of Ge/Si(100) Growth by Ion-Assisted Molecular Beam Epitaxy

1992 ◽  
Vol 268 ◽  
Author(s):  
C.J. Tsai ◽  
H.A. Atwater
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Elastic Stability ◽  
Kinetic Mechanism ◽  
Layer Growth ◽  
Layer By Layer ◽  
Island Formation ◽  
Defect Generation ◽  
Linear Elastic ◽  
Amplitude Fluctuations

ABSTRACTWe have observed a suppression of island formation and an increase in the thickness limit for layer-by-layer growth of Ge on Si (100) by ion-assisted molecular beam epitaxy. Island suppression is observed both for ion energies at which surface defect generation dominates bulk defect generation and at which the majority of defects generated are bulk defects. This experiment, in conjunction with results of a linear elastic stability model for islanding, reveals that the kinetic mechanism for the suppression of island formation via ion bombardment is the reduction of surface amplitude fluctuations during the early stages of growth.

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