InN Nanostructures: Strain and Morphology

2003 ◽  
Vol 798 ◽  
Author(s):  
Francois Demangeot ◽  
Jean Frandon ◽  
Claire Pinquier ◽  
Michel Caumont ◽  
Olivier Briot ◽  
...  
Keyword(s):  
Specific Growth ◽  
Careful Analysis ◽  
Growth Conditions ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Metal Organic ◽  
Raman Study ◽  
Gan Buffer Layer ◽  
Key Parameter

ABSTRACTWe presented an experimental work on InN nanostructures grown on a GaN buffer layer deposited on sapphire (0001) by Metal Organic Vapor Phase Epitaxy. InN islands of controlled sizes were fabricated by using specific growth conditions and taking advantage of self-organization that results from Stranski-Krastanov growth mode. Then nanometric islands as small as 25 nm were characterized by using atomic force microscopy (AFM) and micro-Raman spectroscopy. AFM measurements revealed that the current shape of islands correspond to truncated hexagons. In-plane residual strain field was deduced from the E2 phonon frequency shift in micro-Raman spectra recorded on islands of various sizes. Careful analysis of these data made clear that the key parameter in determining the strain magnitude was the height of the islands: this was not surprising, keeping in mind that the shape was roughly independent of the size. Nevertheless, the dislocation density was believed to increase as function of the island thickness, leading to various degrees of strained relaxation, as probed by the present micro-Raman study. This conclusion was reinforced by the strain variation on the facets of single islands with respect to its value at the centre.

Gallium Nitride Growth Using Diethylgallium Chloride as an Alternative Gallium Source

1998 ◽  
Vol 537 ◽  
Author(s):  
Ling Zhang ◽  
Rong Zhang ◽  
Marek P. Boleslawski ◽  
T.F. Kuech
Keyword(s):  
Growth Conditions ◽  
Rocking Curve ◽  
X Ray ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Curve Line ◽  
Metal Organic ◽  
Increasing Temperature ◽  
Trimethyl Gallium

AbstractMetal organic vapor phase epitaxy (MOVPE) of GaN has been carried out using diethyl gallium chloride (DEGaCI) and ammonia. The growth rate and efficiency of the DEGaCl-based growth decreases with increasing temperature when compared to trimethyl gallium (TMG)-based growth under similar conditions. Both low temperature buffer and the high temperature GaN layers were grown using the DEGaCI-NH3 precursor combination on the basal plane of sapphire and compared to similar structures grown using TMG and NH3. DEGaCl-based growth reveals an improved growth behavior under identical growth conditions to the conventional TMGa and ammonia growth. X-ray, Hall, and atomic force microscopy (AFM) measurements have been carried out on these samples providing a direct comparison of materials properties associated with these growth precursors. For the DEGaCl-based growth, the x-ray rocking curve line width, using the (0002) reflection, is as low as 300 arcsec on a 2.5-micron thick film. A RMS surface roughness of ∼0.5nm measured over a 10x10 micron area.

scholarly journals Gallium Nitride Growth Using Diethylgallium Chloride as an Alternative Gallium Source

1999 ◽  
Vol 4 (S1) ◽  
pp. 351-356
Author(s):  
Ling Zhang ◽  
Rong Zhang ◽  
Marek P. Boleslawski ◽  
T.F. Kuech
Keyword(s):  
Growth Conditions ◽  
Rocking Curve ◽  
X Ray ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Curve Line ◽  
Metal Organic ◽  
Increasing Temperature ◽  
Trimethyl Gallium

Metal organic vapor phase epitaxy (MOVPE) of GaN has been carried out using diethyl gallium chloride (DEGaCl) and ammonia. The growth rate and efficiency of the DEGaCl-based growth decreases with increasing temperature when compared to trimethyl gallium (TMG)-based growth under similar conditions. Both low temperature buffer and the high temperature GaN layers were grown using the DEGaCl-NH3 precursor combination on the basal plane of sapphire and compared to similar structures grown using TMG and NH3. DEGaCl-based growth reveals an improved growth behavior under identical growth conditions to the conventional TMGa and ammonia growth. X-ray, Hall, and atomic force microscopy (AFM) measurements have been carried out on these samples providing a direct comparison of materials properties associated with these growth precursors. For the DEGaCl-based growth, the x-ray rocking curve line width, using the (0002) reflection, is as low as 300 arcsec on a 2.5-micron thick film. A RMS surface roughness of ∼0.5nm measured over a 10×10 micron area.

Formation of Self-Assembled Nanometer-Scale InP Islands on Silicon Substrates

2000 ◽  
Vol 618 ◽  
Author(s):  
A.S. Bakin ◽  
D. Piester ◽  
H.-H. Wehmann ◽  
A.A. Ivanov ◽  
A. Schlachetzki ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Atomic Force Microscopy ◽  
Vapor Phase ◽  
Three Dimensional ◽  
Nanometer Scale ◽  
Silicon Substrates ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Metal Organic

ABSTRACTThree-dimensional islands of InP have been reproducibly grown in the Stranski-Krastanow growth mode on Si (001) and (111) by using metal-organic vapor phase epitaxy in order to obtain nanometer-scale quantum dots. Atomic-force microscopy was used to determine the morphology of the samples and to evaluate the dimensions of the islands. Formation of three-dimensional islands with densities as high as 2.5×1010 cm−2 and small sizes have been observed. The evolution of island morphology is explained in terms of strain-relaxing mechanisms at the first stages of InP/Si heteroepitaxy.

The Initial Stages of Growth of Ordered GaInP and GaInAs Grown by Metal Organic Vapor Phase Epitaxy

1999 ◽  
Vol 583 ◽  
Author(s):  
M. C. Hanna ◽  
A. Mascarenhas ◽  
Hyeonsik M. Cheong
Keyword(s):  
Raman Spectroscopy ◽  
Atomic Force Microscopy ◽  
Direct Evidence ◽  
Force Microscopy ◽  
Step Flow ◽  
Organic Vapor ◽  
Stages Of Growth ◽  
Atomic Force ◽  
Metal Organic ◽  
Step Flow Growth

AbstractWe have used atomic force microscopy (AFM) and Raman spectroscopy to investigate the development of the surface morphology of (001) direct and vicinal GaInP and GaInAs grown under conditions to produce strong CUPtB ordering. Raman spectroscopy provided direct evidence of CuPtB ordering in layers as thin as 10 nm for GaInP and 5 nm for GaInAs. We find that the morphology of GaInP and GaInAs on (001)6B substrates consists of ridges, which are aligned predominately along the [110] direction (A-direction). These ridges are well developed even at layer thicknesses of 2 nm, and their sides consist of step-bunches and near (001) terraces. On (001) direct substrates, the GaInP morphology is similar to that obtained on 6B substrates, although the step bunches have no preferential orientation, while GaInAs (001) growth proceeds by a combination of 2D-island and step flow growth. We discuss possible reasons for the differences in the morphology of ordered GaInP and GaInAs. The results of this work suggest it may be difficult to produce abrupt heterointerfaces in structures containing ordered GalnP and GaInAs alloys.

Optimization of GaN Barriers During the Growth of InGaN/GaN Quantum Wells at Low Temperature

2008 ◽  
Vol 1108 ◽  
Author(s):  
Kalyan R Kasarla ◽  
Wenyu Chiang ◽  
Ronak Rahimi ◽  
D. Korakakis
Keyword(s):  
Low Temperature ◽  
Quantum Wells ◽  
Defect Density ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Metal Organic ◽  
Tapping Mode Afm ◽  
Surface Morphologies

AbstractInGaN/GaN MQWs are grown on c-plane sapphire substrates using a low pressure metal organic vapor phase epitaxy (MOVPE) system. Trimethylgallium (TMGa), Triethylgallium (TEGa), Trimethylindium (TMIn) and ammonia were used as precursors for Ga, In and N, respectively and the growths were carried out at low temperature. Structural properties of grown MQWs are characterized using atomic force microscopy (AFM), and scanning electron microscope (SEM) and x-ray diffraction technique (XRD) is used to calculate the Indium incorporation in these MQWs. Surface morphologies over large areas of InGaN/GaN MQWs are observed using the tapping mode AFM; results indicate the surface roughness depends on the barrier thickness. Density of V- defects, effect of barrier width on the surface morphology and also on V-defect density will be presented and discussed.

HVPE and MOVPE GaN Growth on Slightly Misoriented Sapphire Substrates

1999 ◽  
Vol 595 ◽  
Author(s):  
Olivier Parillaud ◽  
Volker Wagner ◽  
Hans-Jörg Bühlmann ◽  
François Lelarge ◽  
Marc Ilegems
Keyword(s):  
Substrate Surface ◽  
Growth Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Step Flow ◽  
Sapphire Substrates ◽  
Atomic Force ◽  
Step Flow Growth ◽  
Gan Buffer Layer

AbstractWe present preliminary results on gallium nitride growth by HVPE on C-plane sapphire with 2, 4 and 6 degrees misorientation towards M and A directions. A nucleation GaN buffer layer is deposited prior the growth by MOVPE. Surface morphology and growth rates are compared with those obtained on exact C-plane oriented sapphire, for various growth conditions. As expected, the steps already present on the substrate surface help to initiate a directed step-flow growth mode. The large hillocks, which are typical for HVPE GaN layers on (0001) sapphire planes, are replaced by more or less parallel macro-steps. The width and height of these steps, due to step bunching effect, depend directly on the angle of misorientation and on the growth conditions, and are clearly visible by optical or scanning electron microscopy. Atomic force microscopy and X-ray diffraction measurements have been carried out to quantify the surface roughness and crystal quality.

Annealing effect of scratch characteristics of ZnMgO epilayers on R-plane sapphire

2021 ◽  
Vol 112 (2) ◽  
pp. 158-163
Author(s):  
Hua-Chiang Wen ◽  
Ming-Chu Hsieh ◽  
Yu-Pin Lan ◽  
Wu-Ching Chou
Keyword(s):  
Atomic Force Microscopy ◽  
Vapor Phase ◽  
Annealing Treatment ◽  
Annealing Effect ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Metal Organic ◽  
Substrate Temperatures ◽  
Microscopy Examination

Abstract The nanotribological properties of Zn0.75Mg0.25O grown on R-plane sapphire using metal-organic vapor-phase epitaxy at different substrate temperatures (RT, 600, 700 and 800 °C) were investigated. A slight sliding track was observed at ramped loads of 250 μN, and an obvious bulge edge surrounding the groove was observed at ramped loads of 1 000 μN. Because of the annealing treatment, all the Zn0.75Mg0.25O coatings showed a reconstruction phenomenon of crystallites. The volumes of the bulge edges were as high as 30% in the annealed specimens and were larger than the volumes of the RT-treated specimens when ramped loads of 1 000 μN were applied. Under frictional loading, atomic force microscopy examination of scratch-tested films indicated lower bonding forces on R-plane sapphire than M-plane sapphire.

scholarly journals HVPE and MOVPE GaN growth on slightly misoriented sapphire substrates

2000 ◽  
Vol 5 (S1) ◽  
pp. 124-130 ◽  
Author(s):  
Olivier Parillaud ◽  
Volker Wagner ◽  
Hans-Jörg Bühlmann ◽  
François Lelarge ◽  
Marc Ilegems
Keyword(s):  
Substrate Surface ◽  
Growth Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Step Flow ◽  
Sapphire Substrates ◽  
Atomic Force ◽  
Step Flow Growth ◽  
Gan Buffer Layer

We present preliminary results on gallium nitride growth by HVPE on C-plane sapphire with 2, 4 and 6 degrees misorientation towards M and A directions. A nucleation GaN buffer layer is deposited prior the growth by MOVPE. Surface morphology and growth rates are compared with those obtained on exact C-plane oriented sapphire, for various growth conditions. As expected, the steps already present on the substrate surface help to initiate a directed step-flow growth mode. The large hillocks, which are typical for HVPE GaN layers on (0001) sapphire planes, are replaced by more or less parallel macro-steps. The width and height of these steps, due to step bunching effect, depend directly on the angle of misorientation and on the growth conditions, and are clearly visible by optical or scanning electron microscopy. Atomic force microscopy and X-ray diffraction measurements have been carried out to quantify the surface roughness and crystal quality.

scholarly journals Optical characterization of thin Al2O3 layers deposited by magnetron sputtering technique at industrial conditions for applications in glazing

2020 ◽  
Vol 38 (1) ◽  
pp. 108-115
Author(s):  
Piotr Dywel ◽  
Łukasz Skowroński
Keyword(s):  
Magnetron Sputtering ◽  
Optical Constants ◽  
Specific Growth ◽  
Gas Injection ◽  
Growth Conditions ◽  
Light Transmittance ◽  
Force Microscopy ◽  
Alumina Films ◽  
Atomic Force

AbstractIn this study, thin Al2O3 films (11 nm – 82 nm) were deposited by means of a recently developed pulse gas injection magnetron sputtering method and investigated by means of atomic force microscopy, spectroscopic ellipsometry and spectrophotometry. Quite low values of optical constants (1.581 to 1.648 at λ = 550 nm) of the alumina films are directly associated with specific growth conditions (pulse injection of the reactive or reactive + inert gas) in the pulse gas injection magnetron sputtering process. The light transmittance of Al2O3/glass systems (86 % to 90 %) is only a few percent lower than that calculated for glass (93 %).

Growth of High Quality c-plane AlN on a-plane Sapphire

2009 ◽  
Vol 1202 ◽  
Author(s):  
Reina Miyagawa ◽  
Jiejun Wu ◽  
Hideto Miyake ◽  
Kazumasa Hiramatsu
Keyword(s):  
Vapor Phase ◽  
Vapor Phase Epitaxy ◽  
Hydride Vapor Phase Epitaxy ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Organic Vapor ◽  
Atomic Force ◽  
Metal Organic ◽  
Dislocations Density ◽  
Reactor Pressure

Abstractc-plane (0001) AlN layers were grown on sapphire (11-20) and (0001) substrates by hydride vapor phase epitaxy (HVPE) and metal-organic vapor phase epitaxy (MOVPE), respectively. The growth temperatures were adjusted from 1430-1500 °C and the reactor pressure was kept constant at 30 Torr. Mirror and flat c-plane AlN were obtained grown on both a-plane and c-plane sapphire. Crystalline quality and surface roughness are improved with increasing growth temperature, detected by high resolution X-ray diffraction (HRXRD) and atomic force microscopy (AFM). The Full widths at half maximum (FWHM) values of (10-12) diffraction are 519 and 1219 arcsec for c-plane AlN grown on a-plane sapphire and c-plane sapphire, respectively. It indicates that a-plane sapphire substrate benefits to decrease dislocations density.

Sign in / Sign up

Export Citation Format

Share Document