Epitaxial Growth of AlN on 6H-SiC (1120) by Molecular-Beam Epitaxy and Effect of Low-Temperature Buffer Layer

ABSTRACTAluminum nitride (AlN) has been grown on 6H-silicon carbide (SiC) substrates with the non-polar (1120) face using rf plasma-assisted molecular-beam epitaxy (rf-MBE). Reflection high-energy electron diffraction (RHEED) revealed that AlN and 6H-SiC (1120) had an exact epitaxial relationship, i.e., [1120]AlN|[1120]SiC and [0001]AlN∥[0001]SiC. From the result of microscopic Raman scattering spectroscopy, the stacking structure of the AlN epitaxial layer was suggested to be a 2H structure, not a 6H structure. A directly grown AlN layer and layer with AlN low-temperature (LT) buffer layer were investigated based on atomic force microscopy (AFM) and X-ray diffraction (XRD).

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A Study on the Growth of Cubic GaN Films Using an AlGaAs Buffer Layer Grown on GaAs (100) by Plasma-Assisted Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-639-g3.46 ◽

2000 ◽

Vol 639 ◽

Author(s):

Ryuhei Kimura ◽

Kiyoshi Takahashi ◽

H. T. Grahn

Keyword(s):

Molecular Beam Epitaxy ◽

Buffer Layer ◽

Molecular Beam ◽

High Energy ◽

Rf Plasma ◽

Cubic Phase ◽

X Ray Diffraction ◽

X Ray ◽

Cubic Gan

ABSTRACTAn investigation of the growth mechanism for RF-plasma assisted molecular beam epitaxy of cubic GaN films using a nitrided AlGaAs buffer layer was carried out by in-situ reflection high energy electron diffraction (RHEED) and high resolution X-ray diffraction (HRXRD). It was found that hexagonal GaN nuclei grow on (1, 1, 1) facets during nitridation of the AlGaAs buffer layer, but a highly pure, cubic-phase GaN epilayer was grown on the nitrided AlGaAs buffer layer.

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Reflection High Energy Electron Diffraction and Atomic Force Microscopy Studies of MnxSc(1-x) Alloys Grown on MgO(001) Substrates by Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/opl.2011.458 ◽

2011 ◽

Vol 1295 ◽

Author(s):

Costel Constantin ◽

Abhijit Chinchore ◽

Arthur R. Smith

Keyword(s):

Atomic Force Microscopy ◽

Molecular Beam Epitaxy ◽

Electron Diffraction ◽

Molecular Beam ◽

High Energy ◽

Energy Electron ◽

High Energy Electron ◽

Force Microscopy ◽

Atomic Force ◽

Growth Method

ABSTRACTThe combination of the molecular beam epitaxy growth method with the in-situ reflection high energy electron diffraction measurements currently offers unprecedented control of crystalline growth materials. We present here a stoichiometric study of MnxSc(1-x) [x = 0, 0.03, 0.05, 0.15, 0.25, 0.35, and 0.50] thin films grown on MgO(001) substrates with this growth method. Reflection high energy electron diffraction and atomic force microscopy measurements reveal alloy behavior for all of our samples. In addition, we found that samples Mn0.10Sc0.90 and Mn0.50Sc0.50 display surface self-assembled nanowires with a length/width ratio of ~ 800 – 2000.

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Epitaxial Dy2O3 Thin Films Grown on Ge(100) Substrates by Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-1252-i03-01 ◽

2010 ◽

Vol 1252 ◽

Cited By ~ 2

Author(s):

Md. Nurul Kabir Bhuiyan ◽

Mariela Menghini ◽

Christel Dieker ◽

Jin Won Seo ◽

Jean-Pierre Locquet ◽

...

Keyword(s):

Molecular Beam Epitaxy ◽

Photoelectron Spectroscopy ◽

Molecular Beam ◽

High Mobility ◽

High Energy ◽

Epitaxial Relationship ◽

Dysprosium Oxide ◽

X Ray ◽

Force Microscopy ◽

Diffraction Patterns

AbstractDysprosium oxide (Dy2O3) films are grown epitaxially on high mobility Ge(100) substrates by molecular beam epitaxy system. Reflection high energy electron diffraction patterns and X-ray diffraction spectra show that single crystalline cubic Dy2O3 films are formed on Ge(100) substrates. The epitaxial-relationship is identified as Dy2O3 (110)║Ge(100) and Dy2O3 [001]║Ge[011]. Atomic force microscopy results show that the surface of the Dy2O3 film is uniform, flat and smooth with root mean square surface roughness of about 4.6Å. X-ray photoelectron spectroscopy including depth profiles confirms the composition of the films being close to Dy2O3. TEM measurements reveal a sharp, crystalline interface between the oxide and Ge.

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Epitaxial Growth and Characterization of NbxTi1−xO2 Rutile Films by Oxygen-Plasma-Assisted Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-401-85 ◽

1995 ◽

Vol 401 ◽

Cited By ~ 4

Author(s):

Y. Gao ◽

S. A. Chambers

Keyword(s):

Molecular Beam Epitaxy ◽

Photoelectron Spectroscopy ◽

Oxygen Plasma ◽

Molecular Beam ◽

High Energy ◽

Epitaxial Films ◽

Layer By Layer ◽

Force Microscopy ◽

Atomic Force

AbstractEpitaxial films of NbxTi1−xO2 rutile were grown on TiO2 (110) and (100) at 600 °C by oxygen-plasma-assisted molecular beam epitaxy using elemental Ti and Nb sources. The epitaxial films were characterized by means of reflection high-energy and low-energy electron diffraction (RHEED/LEED), x-ray photoelectron spectroscopy and diffraction (XPS/XPD), ultraviolet photoemission spectroscopy (UPS) and atomic force microscopy (AFM). The epitaxial films grow in a layer-by-layer fashion and have excellent short- and long-range structure order at x≤0.3 on TiO2(110) and at x≤0.15 on TiO2(100). However, the epitaxial films become rough and disorder at higher doping levels. Nb substitutionally incorporates at cation lattice sites, leading to NbxTi1−xO2 solid solutions. In addition, the oxidation state of Nb in the NbxTi1−xO2 films has been determined to be +4.

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GaN Epitaxial Growth Process at High Growth Temperature by NH3 Source Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-798-y10.67 ◽

2003 ◽

Vol 798 ◽

Author(s):

Naoki Ohshima ◽

Akihiro Sugihara ◽

Naoya Yoshida ◽

Naohiko Okabe

Keyword(s):

Molecular Beam Epitaxy ◽

Epitaxial Layer ◽

Growth Temperature ◽

Molecular Beam ◽

High Growth ◽

High Energy ◽

Force Microscopy ◽

Gas Source ◽

Atomic Force ◽

Surface Morphologies

ABSTRACTWe have investigated in detail dependence of annealing GaN buffer layer and GaN growth processes on a sapphire substrate at a high temperature of 1000 degree C. The GaN layers are grown by NH3 gas source molecular beam epitaxy. The behavior of GaN buffer and epitaxial layer has been observed by in-situ reflection high-energy electron diffraction and the surface morphologies of as-grown and chemically etched GaN layers by atomic force microscopy. It is found that there is distinct difference in the surface morphology of epitaxial GaN layer between at growth temperatures of below 950 degree C and that of 1000 degree C. It has been considered that the growth kinetics of GaN epitaxial layer extremely depends on the growth temperature.

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Growth of MgO by Metal-Organic Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-606-45 ◽

1999 ◽

Vol 606 ◽

Cited By ~ 4

Author(s):

Feng Niu ◽

Brent.H. Hoerman ◽

Bruce.W. Wessels

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Rf Plasma ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Transmission Electron ◽

Auger Spectrometry ◽

Metal Organic ◽

Precursor Decomposition

AbstractMgO thin films were deposited on (100) Si substrates by metal-organic molecular beam epitaxy (MOMBE). Magnesium acetylacetonate was used as the precursor and an oxygen RF plasma was used as the oxidant. The films were characterized by a combination of transmission electron microscopy, Auger spectrometry and atomic force microscopy. Analyses indicate that the films directly deposited on Si substrates are stoichiometric, phase-pure, polycrystalline MgO with a [100] texture. Carbon contamination of the films resulting from precursor decomposition was not observed within detection limits. Furthermore, the growth rate of MgO has been systematically investigated as a function of growth temperature.

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Growth and Characterization of Epitaxial Al1−xInxN Films Grown on Sapphire (0001) by Plasma Source Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-639-g6.54 ◽

2000 ◽

Vol 639 ◽

Cited By ~ 1

Author(s):

M. J. Lukitsch ◽

G. W. Auner ◽

R. Naik ◽

V. M. Naik

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Plasma Source ◽

High Energy ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Alloy Segregation

ABSTRACTEpitaxial Al1−xInxN films (thickness ∼150 nm) with 0 ≤ × ≤ 1 have been grown by Plasma Source Molecular Beam Epitaxy on Sapphire (0001) at a low substrate temperature of 375°C and were characterized by reflection high energy electron diffraction (RHEED), x-ray diffraction (XRD), and atomic force microscopy (AFM). Both RHEED and XRD measurements confirm the c-plane growth of Al1-xInxN films on sapphire (0001) with the following epitaxial relations: Nitride [0001] ∥ Sapphire [0001] and Nitride < 0110 > ∥ Sapphire <2110>. The films do not show any alloy segregation. However, the degree of crystalline mosaicity and the compositional fluctuation increases with increasing In concentration. Further, AFM measurements show an increased surface roughness with increasing In concentration in the alloy films.

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GaAs-on-Ge Heteroepitaxy by Atomic Hydrogen-Assisted Molecular Beam Epitaxy (H-MBE)

MRS Proceedings ◽

10.1557/proc-399-203 ◽

1995 ◽

Vol 399 ◽

Cited By ~ 1

Author(s):

Yoshitaka Okada ◽

James S. Harris ◽

Atsushi Sutoh ◽

Mitsuo Kawabe

Keyword(s):

Molecular Beam Epitaxy ◽

Atomic Hydrogen ◽

Molecular Beam ◽

High Energy ◽

Atomic Scale ◽

Layer By Layer ◽

High Quality ◽

Force Microscopy ◽

Atomic Force ◽

Growth System

ABSTRACTThe purpose of this work is to achieve a high-quality epitaxy of GaAs-on-Ge system at low growth temperatures of 300 ∼ 400°C, by atomic hydrogen-assisted molecular beam epitaxy (H-MBE), in attempt to reduce Ge segregation to a minimum and to realize a layer-by-layer two-dimensional (2D) growth mode from the initial stages of the growth. A high-quality heteroepitaxy is expected in H-MBE technique as atomic H is known to act as an effective surfactant modifying the kinetics and energetics of the growth, which are practically difficult to control on atomic-scale unless a third element like a surfactant is introduced into the growth system. It is shown with the support of reflection high-energy electron diffraction (RHEED), secondary ion mass spectroscopy (SIMS), and atomic force microscopy (AFM) characterization that an enhanced layer-by-layer 2D growth can actually be realized and (2×4) GaAs(001) surface can be achieved in low-temperature heteroepitaxy on vicinal Ge(001) substrates at 400 °C by H-MBE.

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Structural and Optical Properties of InAsSbBi Grown by Molecular Beam Epitaxy on Offcut GaSb Substrates

Photonics ◽

10.3390/photonics8060215 ◽

2021 ◽

Vol 8 (6) ◽

pp. 215

Author(s):

Rajeev R. Kosireddy ◽

Stephen T. Schaefer ◽

Marko S. Milosavljevic ◽

Shane R. Johnson

Keyword(s):

Molecular Beam Epitaxy ◽

Molecular Beam ◽

Optical Quality ◽

X Ray Diffraction ◽

Interface Quality ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Lateral Variations

Three InAsSbBi samples are grown by molecular beam epitaxy at 400 °C on GaSb substrates with three different offcuts: (100) on-axis, (100) offcut 1° toward [011], and (100) offcut 4° toward [011]. The samples are investigated using X-ray diffraction, Nomarski optical microscopy, atomic force microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The InAsSbBi layers are 210 nm thick, coherently strained, and show no observable defects. The substrate offcut is not observed to influence the structural and interface quality of the samples. Each sample exhibits small lateral variations in the Bi mole fraction, with the largest variation observed in the on-axis growth. Bismuth rich surface droplet features are observed on all samples. The surface droplets are isotropic on the on-axis sample and elongated along the [011¯] step edges on the 1° and 4° offcut samples. No significant change in optical quality with offcut angle is observed.

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