Molecular beam homoepitaxial growth of MgO(001)

We describe homoepitaxial growth and detailed in situ characterization of MgO(001). We have used, for the first time, high-speed Auger electron spectroscopy as a real-time probe of film composition during growth. Excellent short-range and long-range crystallographic order are achieved in films grown to a thickness of several hundred angstroms in the substrate temperature range of 450 °C to 750 °C. Moreover, the films become more laminar as the growth temperature increases, suggesting that MgO grows homoepitaxially by the step-flow growth mechanism at elevated temperature. The surfaces of films grown at 650°and 750 °C are smoother than those obtained by cleaving MgO(001).

Download Full-text

In situ characterization of a cold and short pulsed molecular beam by femtosecond ion imaging

Physical Chemistry Chemical Physics ◽

10.1039/b822960k ◽

2009 ◽

Vol 11 (20) ◽

pp. 3958 ◽

Cited By ~ 30

Author(s):

Daniel Irimia ◽

Rob Kortekaas ◽

Maurice H. M. Janssen

Keyword(s):

Molecular Beam ◽

Ion Imaging ◽

In Situ Characterization

Download Full-text

Temperature-Dependent Photoluminescence of ZnO Thin Films Grown on Off-Axis SiC Substrates by APMOCVD

Materials ◽

10.3390/ma14041035 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1035

Author(s):

Ivan Shtepliuk ◽

Volodymyr Khranovskyy ◽

Arsenii Ievtushenko ◽

Rositsa Yakimova

Keyword(s):

Optical Properties ◽

Structural Quality ◽

Organic Chemical ◽

Zno Films ◽

Vicinal Surfaces ◽

Temperature Dependent ◽

Step Flow ◽

Step Flow Growth ◽

First Time ◽

Temperature Dependent Photoluminescence

The growth of high-quality ZnO layers with optical properties congruent to those of bulk ZnO is still a great challenge. Here, for the first time, we systematically study the morphology and optical properties of ZnO layers grown on SiC substrates with off-cut angles ranging from 0° to 8° by using the atmospheric pressure meta–organic chemical vapor deposition (APMOCVD) technique. Morphology analysis revealed that the formation of the ZnO films on vicinal surfaces with small off-axis angles (1.4°–3.5°) follows the mixed growth mode: from one side, ZnO nucleation still occurs on wide (0001) terraces, but from another side, step-flow growth becomes more apparent with the off-cut angle increasing. We show for the first time that the off-cut angle of 8° provides conditions for step-flow growth of ZnO, resulting in highly improved growth morphology, respectively structural quality. Temperature-dependent photoluminescence (PL) measurements showed a strong dependence of the excitonic emission on the off-cut angle. The dependences of peak parameters for bound exciton and free exciton emissions on temperature were analyzed. The present results provide a correlation between the structural and optical properties of ZnO on vicinal surfaces and can be utilized for controllable ZnO heteroepitaxy on SiC toward device-quality ZnO epitaxial layers with potential applications in nano-optoelectronics.

Download Full-text

Anin situatomic force microscope for normal-incidence nanofocus X-ray experiments

Journal of Synchrotron Radiation ◽

10.1107/s1600577516011437 ◽

2016 ◽

Vol 23 (5) ◽

pp. 1110-1117 ◽

Cited By ~ 3

Author(s):

M. V. Vitorino ◽

Y. Fuchs ◽

T. Dane ◽

M. S. Rodrigues ◽

M. Rosenthal ◽

...

Keyword(s):

Thin Film ◽

Atomic Force Microscope ◽

High Speed ◽

Normal Incidence ◽

Organic Thin Film ◽

X Ray ◽

Atomic Force ◽

Synchrotron Beamlines

A compact high-speed X-ray atomic force microscope has been developed forin situuse in normal-incidence X-ray experiments on synchrotron beamlines, allowing for simultaneous characterization of samples in direct space with nanometric lateral resolution while employing nanofocused X-ray beams. In the present work the instrument is used to observe radiation damage effects produced by an intense X-ray nanobeam on a semiconducting organic thin film. The formation of micrometric holes induced by the beam occurring on a timescale of seconds is characterized.

Download Full-text

In-situ characterization of II/VI molecular beam epitaxy growth using reflection high-energy electron diffraction oscillations

Journal of Crystal Growth ◽

10.1016/0022-0248(94)91270-x ◽

1994 ◽

Vol 137 (1-2) ◽

pp. 187-194 ◽

Cited By ~ 12

Author(s):

J.M. Gaines

Keyword(s):

Molecular Beam Epitaxy ◽

Electron Diffraction ◽

Molecular Beam ◽

High Energy ◽

Energy Electron ◽

Molecular Beam Epitaxy Growth ◽

High Energy Electron ◽

In Situ Characterization

Download Full-text

Bi induced step-flow growth in the homoepitaxial growth of Au(111)

Applied Surface Science ◽

10.1016/j.apsusc.2005.01.015 ◽

2005 ◽

Vol 252 (2) ◽

pp. 364-371 ◽

Cited By ~ 6

Author(s):

M. Kamiko ◽

H. Mizuno ◽

H. Chihaya ◽

J.-H. Xu ◽

I. Kojima ◽

...

Keyword(s):

Step Flow ◽

Homoepitaxial Growth ◽

Step Flow Growth

Download Full-text

Surface Morphology and Microstructure Evolution of Single Crystal Diamond during Different Homoepitaxial Growth Stages

Materials ◽

10.3390/ma14205964 ◽

2021 ◽

Vol 14 (20) ◽

pp. 5964

Author(s):

Guoqing Shao ◽

Juan Wang ◽

Shumiao Zhang ◽

Yanfeng Wang ◽

Wei Wang ◽

...

Keyword(s):

Surface Morphology ◽

Single Crystal ◽

Cross Section ◽

Growth Model ◽

Diamond Growth ◽

Step Flow ◽

Homoepitaxial Growth ◽

Diamond Substrate ◽

Single Crystal Diamond ◽

Step Flow Growth

Homoepitaxial growth of step-flow single crystal diamond was performed by microwave plasma chemical vapor deposition system on high-pressure high-temperature diamond substrate. A coarse surface morphology with isolated particles was firstly deposited on diamond substrate as an interlayer under hillock growth model. Then, the growth model was changed to step-flow growth model for growing step-flow single crystal diamond layer on this hillock interlayer. Furthermore, the surface morphology evolution, cross-section and surface microstructure, and crystal quality of grown diamond were evaluated by scanning electron microscopy, high-resolution transmission electron microcopy, and Raman and photoluminescence spectroscopy. It was found that the surface morphology varied with deposition time under step-flow growth parameters. The cross-section topography exhibited obvious inhomogeneity in crystal structure. Additionally, the diamond growth mechanism from the microscopic point of view was revealed to illustrate the morphological and structural evolution.

Download Full-text

The Dynamical Transition to Step-Flow Growth During Homoepitaxy of GaAs (001)

MRS Proceedings ◽

10.1557/proc-312-15 ◽

1993 ◽

Vol 312 ◽

Cited By ~ 1

Author(s):

B. G. Orr ◽

J. Sudijono ◽

M. D. Johnson

Keyword(s):

Scanning Tunneling Microscope ◽

Molecular Beam ◽

Scanning Tunneling ◽

Oscillatory Regime ◽

Step Flow ◽

Microscope Images ◽

Step Density ◽

Step Flow Growth ◽

Direct Correspondence ◽

Density Results

AbstractThe evolution of surface morphology of molecular-beam-epitaxy-grown GaAs (001) has been studied by scanning tunneling microscope. Images show that in the early stages of deposition the morphology oscillates between one -with twodimensional nucleation and coalescing islands, i.e. flat terraces. After the initial oscillatory regime, the system evolves to a dynamical steady state. This state is characterized by a constant step density. As such, the growth mode can be called a generalized step flow. Comparison with RHEED shows that there is a direct correspondence between the surface step density and the RHEED specular intensity. An increase in step density results in a decrease in specular intensity. Additionally, further deposition beyond 120 monolayers (up to 1450 monolayers) display a slowly increasing surface roughness.

Download Full-text