scholarly journals Growth of NbO2 by Molecular-Beam Epitaxy and Characterization of its Metal-Insulator Transition

MRS Advances ◽  
2017 ◽  
Vol 2 (52) ◽  
pp. 3031-3036 ◽  
Author(s):  
Lindsey E. Noskin ◽  
Ariel Seidner H. ◽  
Darrell G. Schlom
Keyword(s):  
Electrical Resistivity ◽  
Molecular Beam Epitaxy ◽  
Growth Temperature ◽  
Molecular Beam ◽  
Film Growth ◽  
Growth Parameters ◽  
Growth Conditions ◽  
Lower Growth ◽  
Rutile Structure ◽  
Partial Pressures

ABSTRACTThin films of NbO2 are synthesized by oxide molecular-beam epitaxy on (001) MgF2 substrates, which are isostructural (rutile structure) with NbO2. Two growth parameters are systematically varied in order to identify appropriate growth conditions: growth temperature and the partial pressure of O2 during film growth. θ-2θ X-ray diffraction measurements identify two dominant phases in this system at background oxygen pressures in the (0.2–6)×10–7 Torr range: rutile NbO2 is favored at higher growth temperature, while Nb2O5 forms at lower growth temperature. Electrical resistivity measurements were made between 350 K and 675 K on three epitaxial NbO2 films in a nitrogen ambient. These measurements show that NbO2 films grown in higher partial pressures of molecular oxygen have larger temperature-dependent changes in electrical resistivity and higher resistivity at room temperature.

Impact of Buffered Layer Growth Conditions on Grown-In Vacancy Concentrations in Molecular Beam Epitaxy Silicon Germanium

2004 ◽  
Vol 809 ◽  
Author(s):  
Kareem M. Shoukri ◽  
Yaser M. Haddara ◽  
Andrew P. Knights ◽  
Paul G. Coleman ◽  
Mohammad M. Rahman ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Buffer Layer ◽  
Point Defects ◽  
Growth Temperature ◽  
Silicon Germanium ◽  
Molecular Beam ◽  
Growth Conditions ◽  
Layer Growth ◽  
Vacancy Clusters ◽  
Temperature And Growth

ABSTRACTSilicon-Germanium (SiGe) has become increasingly attractive to semiconductor manufacturers over the last decade for use in high performance devices. In order to produce thin layers of device grade SiGe with low concentrations of point defects and well-controlled doping profiles, advanced growth and deposition techniques such as molecular beam epitaxy (MBE) are used. One of the key issues in modeling dopant diffusion during subsequent processing is the concentration of grown-in point defects. The incorporation of vacancy clusters and vacancy point defects in 200nm SiGe/Si layers grown by molecular beam epitaxy over different buffer layers has been observed using beam-based positron annihilation spectroscopy. Variables included the type of buffer layer, the growth temperature and growth rate for the buffer, and the growth temperature and growth rate for the top layer. Different growth conditions resulted in different relaxation amounts in the top layer, but in all samples the dislocation density was below 106 cm−2. Preliminary results indicate a correlation between the size, type and concentration of vacancy defects and the buffer layer growth temperature. At high buffer layer growth temperature of 500°C the vacancy point defect concentration is below the PAS detectable limit of approximately 1015 cm−3. As the buffer layer growth is decreased to a minimum value of 300°C, large vacancy clusters are observed in the buffered layer and vacancy point defects are observed in the SiGe film. These results are relevant to the role played by point defects grown-in at temperatures below ∼350°C in modeling dopant diffusion during processing.

scholarly journals Processes of formation of epitaxial arrays of self-catalytic GaP nanowires on Si (111)

2021 ◽  
Vol 2103 (1) ◽  
pp. 012127
Author(s):  
S V Fedina ◽  
V V Fedorov ◽  
Yu S Berdnikov ◽  
G A Sapunov ◽  
I S Mukhin
Keyword(s):  
Molecular Beam Epitaxy ◽  
Growth Temperature ◽  
Surface Density ◽  
Molecular Beam ◽  
Growth Conditions ◽  
Nanowire Arrays

Abstract This study is devoted to the investigation of the effect of growth conditions (growth temperature, values of molecular beam fluxes) on the formation of self-catalytic GaP NW on Si(111), namely surface density, orientation and NW morphology. Nanowire arrays were grown on Si (111) by the plasma-assisted molecular beam epitaxy. It was determined that an increase of the temperature and a decrease of the Ga flux, while maintaining the V/III ratio, reduces the inclined NWs and parasitic islands nucleation probability.

Growth Conditions of Erbium-Oxygen-Doped Silicon Grown by MBE

1996 ◽  
Vol 422 ◽  
Author(s):  
J. Stimmer ◽  
A. Reittinger ◽  
G. Abstreiter ◽  
H. Holzbrecher ◽  
Ch. Buchal
Keyword(s):  
Molecular Beam Epitaxy ◽  
Systematic Study ◽  
Molecular Beam ◽  
Growth Parameters ◽  
Light Emitting Diode ◽  
Growth Conditions ◽  
Light Emitting ◽  
Doped Silicon

AbstractWe report on a systematic study of the growth parameters of erbium-oxygen-doped silicon grown by molecular beam epitaxy. The surface quality of the grown layers was measured in situ by RHEED. The samples were characterized by photoluminescence measurements and SIMS. An Er-O-doped Si light emitting diode grown with the optimized parameters is presented.

scholarly journals Структурные свойства тонких пленок кристаллического топологического изолятора Pb-=SUB=-0.7-=/SUB=-Sn-=SUB=-0.3-=/SUB=-Te на Si(111)

2021 ◽  
Vol 55 (8) ◽  
pp. 625
Author(s):  
А.К. Кавеев ◽  
Д.Н. Бондаренко ◽  
О.Е. Терещенко
Keyword(s):  
Molecular Beam Epitaxy ◽  
Surface Morphology ◽  
Growth Temperature ◽  
Molecular Beam ◽  
Growth Parameters ◽  
Technological Growth

In this work, the selection and optimization of technological growth parameters of thin Pb0.7Sn0.3Te layers up to 300 nm thick, grown on the Si(111) surface at temperatures of 230−400◦C by the method of molecular beam epitaxy was carried out. The surface morphology of the films was studied, and the epitaxial relations were determined. It was shown that, depending on the growth temperature, the surface morphology ranges from relatively narrow terraces to smooth micrometer-sized islands with monoatomic steps on their surface.

Optimization of Ga(In)NAs thin film growth by atomic hydrogen-assisted molecular beam epitaxy

2005 ◽  
Vol 891 ◽  
Author(s):  
Yukiko Shimizu ◽  
Naoya Miyashita ◽  
Yoshitaka Okada
Keyword(s):  
Thin Film ◽  
Optical Properties ◽  
Growth Temperature ◽  
Atomic Hydrogen ◽  
Molecular Beam ◽  
Film Growth ◽  
Thin Film Growth ◽  
Crystal Quality ◽  
Lower Growth ◽  
Growth Method

ABSTRACTThe effect of growth temperature on the crystal quality and optical properties of Ga(In)NAs films was investigated over a range of 340 ∼ 520 °C. We found that Ga(In)NAs films fabricated at lower growth temperatures generally result in an improved crystal quality. An XRD linewidth of as low as 45 arcsec was obtained for a 1 µm-thick Ga0.94In0.06N0.01As0.99 thin film grown at 380 °C. This is ∼1/2 of that grown at the conventionally-adopted growth temperature of 480 °C. After annealing, an improved optical property represented by a higher PL intensity compared to the conventional growth method (annealed, Tgrowth = 480 °C) was also obtained in the 1 µm-thick Ga0.94In0.06N0.01As0.99 thin film grown at low temperature of 380 °C.

scholarly journals Indium-Incorporation with InxGa1-xN Layers on GaN-Microdisks by Plasma-Assisted Molecular Beam Epitaxy

Crystals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 308 ◽  
Author(s):  
ChengDa Tsai ◽  
Ikai Lo ◽  
YingChieh Wang ◽  
ChenChi Yang ◽  
HongYi Yang ◽  
...  
Keyword(s):  
Molecular Beam Epitaxy ◽  
Quantum Wells ◽  
Growth Temperature ◽  
Molecular Beam ◽  
Growth Parameters ◽  
Flux Ratio ◽  
Indium Content ◽  
High Indium Content

Indium-incorporation with InxGa1-xN layers on GaN-microdisks has been systematically studied against growth parameters by plasma-assisted molecular beam epitaxy. The indium content (x) of InxGa1-xN layer increased to 44.2% with an In/(In + Ga) flux ratio of up to 0.6 for a growth temperature of 620 °C, and quickly dropped with a flux ratio of 0.8. At a fixed In/(In + Ga) flux ratio of 0.6, we found that the indium content decreased as the growth temperature increased from 600 °C to 720 °C and dropped to zero at 780 °C. By adjusting the growth parameters, we demonstrated an appropriate InxGa1-xN layer as a buffer to grow high-indium-content InxGa1-xN/GaN microdisk quantum wells for micro-LED applications.

Conducting (Si-Doped) Aluminum Nitride Epitaxial Films Grown by Molecular Beam Epitaxy

1999 ◽  
Vol 572 ◽  
Author(s):  
J. G. Kim ◽  
Madhu Moorthy ◽  
R. M. Park
Keyword(s):  
Growth Temperature ◽  
Molecular Beam ◽  
Growth Parameters ◽  
Growth Conditions ◽  
Preparation Methods ◽  
Molecular Beam Epitaxial ◽  
Si Doped ◽  
Molecular Beam Epitaxial Growth ◽  
First Time ◽  
Selection Of

ABSTRACTAs a member of the III-V nitride semiconductor family, AlN, which has a direct energygap of 6.2eV, has received much attention as a promising material for many applications. However, despite the promising attributes of AlN for various semiconductor devices, research on AlN has been limited and n-type conducting AlN has not been reported. The objective of this research was to understand the factors impacting the conductivity of AlN and to control the conductivity of this material through intentional doping. Prior to the intentional doping study, growth of undoped AlN epilayers was investigated. Through careful selection of substrate preparation methods and growth parameters, relatively low-temperature molecular beam epitaxial growth of AlN films was established which resulted in insulating material. Intentional Si doping during epilayer growth was found to result in conducting films under specific growth conditions. Above a growth temperature of 900°C, AlN films were insulating, however, below a growth temperature of 900°C, the AlN films were conducting. The magnitude of the conductivity and the growth temperature range over which conducting AlN films could be grown were strongly influenced by the presence of a Ga flux during growth. For instance, conducting, Si-doped, AlN films were grown at a growth temperature of 940°C in the presence of a Ga flux while the films were insulating when grown in the absence of a Ga flux at this particular growth temperature. Also, by appropriate selection of the growth parameters, epilayers with n-type conductivity values as large as 0.2 Ω−1 cm−1 for AlN and 17 Ω−1cm−1 for Al0.75Ga0.25N were grown in this work for the first time.

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