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

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.

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

MRS Proceedings ◽

10.1557/proc-618-27 ◽

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.

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

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2020-7766 ◽

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.

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Atomic Force Microscopy Study of GaN Grown on Al2O3(0001) by LP-MOVPE

MRS Proceedings ◽

10.1557/proc-639-g3.28 ◽

2000 ◽

Vol 639 ◽

Author(s):

K. Xu ◽

D. H. Lim ◽

B. L. Liu ◽

X. L. Du ◽

G. H. Yu ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Growth Temperature ◽

Spiral Growth ◽

Initial Growth ◽

Growth Mechanisms ◽

Remarkable Effect ◽

Force Microscopy ◽

Step Flow ◽

Atomic Force ◽

Step Flow Growth

ABSTRACTThere is currently a high degree of interest in understanding the diverse mechanisms that determine the growth morphology of epitaxial films. To understand and control over these mechanisms, it is essential to know how the growth mechanisms are correlated with morphologies. In GaN MOVPE processes, growth temperature has a remarkable effect on the film morphologies and properties. In present work, the temperature dependency of surface morphology of GaN epilayers grown by low-pressure metal-organic vapor phase epitaxy (LP-MOVPE) was studied using atomic force microscopy. It was demonstrated that dislocations strongly influence the growth mechanisms and the morphology of the films. Three growth modes were identified at different growth temperature ranged from 1030°C to 1100°C, which are, (1) spiral growth dominated by dislocation with screw type, (2) monolayer step flow, and (3) nucleation-assisted step flow growth. The significant effect of dislocation on the surface morphologies and growth mechanisms may be attributed to the high dislocation density and higher activation energy for a step overcoming the dislocation pinning in GaN. Because few dislocations will be introduced under monolayer step flow growth mode, we can infer the useful information about GaN initial growth.

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Crystal growth of the core and rotated epitaxial shell of a heterometallic metal-organic framework revealed with atomic force microscopy

Faraday Discussions ◽

10.1039/d1fd00033k ◽

2021 ◽

Author(s):

Fajar Inggit Pambudi ◽

Michael William Anderson ◽

Martin Attfield

Keyword(s):

Atomic Force Microscopy ◽

Crystal Growth ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Force Microscopy ◽

The Core ◽

Atomic Force ◽

Metal Organic ◽

Surface Crystal ◽

Organic Framework

Atomic force microscopy has been used to determine the surface crystal growth of two isostructural metal-organic frameworks, [Zn2(ndc)2(dabco)] (ndc = 1,4-naphthalene dicarboxylate, dabco = 4-diazabicyclo[2.2.2]octane) (1) and [Cu2(ndc)2(dabco)] (2) from...

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Exploring Intramolecular Methyl–Methyl Coupling on a Metal Surface for Edge-Extended Graphene Nanoribbons

Organic Materials ◽

10.1055/s-0041-1726295 ◽

2021 ◽

Vol 03 (02) ◽

pp. 128-133

Author(s):

Zijie Qiu ◽

Qiang Sun ◽

Shiyong Wang ◽

Gabriela Borin Barin ◽

Bastian Dumslaff ◽

...

Keyword(s):

Raman Spectroscopy ◽

Atomic Force Microscopy ◽

High Resolution ◽

Graphene Nanoribbons ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Force Microscopy ◽

Methyl Methyl ◽

Atomic Force ◽

Edge Extension

Intramolecular methyl–methyl coupling on Au (111) is explored as a new on-surface protocol for edge extension in graphene nanoribbons (GNRs). Characterized by high-resolution scanning tunneling microscopy, noncontact atomic force microscopy, and Raman spectroscopy, the methyl–methyl coupling is proven to indeed proceed at the armchair edges of the GNRs, forming six-membered rings with sp3- or sp2-hybridized carbons.

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pH-Dependent Disintegration of Insulin Amyloid Fibrils Monitored with Atomic Force Microscopy and Surface-Enhanced Raman Spectroscopy

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2021.119672 ◽

2021 ◽

pp. 119672

Author(s):

Erwan Darussalam ◽

Orsolya Peterfi ◽

Tanja Deckert-Gaudig ◽

Ludovic Roussille ◽

Volker Deckert

Keyword(s):

Raman Spectroscopy ◽

Atomic Force Microscopy ◽

Amyloid Fibrils ◽

Surface Enhanced Raman Spectroscopy ◽

Force Microscopy ◽

Atomic Force ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Ph Dependent

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Development of Cross-Hatch Morphology During Growth of Lattice Mismatched Layers

MRS Proceedings ◽

10.1557/proc-673-p5.2 ◽

2001 ◽

Vol 673 ◽

Author(s):

A. Maxwell Andrews ◽

J.S. Speck ◽

A.E. Romanov ◽

M. Bobeth ◽

W. Pompe

Keyword(s):

Misfit Dislocation ◽

Film Growth ◽

Strain Relaxation ◽

Dislocation Generation ◽

Force Microscopy ◽

Step Flow ◽

Atomic Force ◽

Subsequent Step ◽

Step Flow Growth ◽

Lateral Scale

ABSTRACTAn approach is developed for understanding the cross-hatch morphology in lattice mismatched heteroepitaxial film growth. It is demonstrated that both strain relaxation associated with misfit dislocation formation and subsequent step elimination (e.g. by step-flow growth) are responsible for the appearance of nanoscopic surface height undulations (0.1-10 nm) on a mesoscopic (∼100 nm) lateral scale. The results of Monte Carlo simulations for dislocation- assisted strain relaxation and subsequent film growth predict the development of cross-hatch patterns with a characteristic surface undulation magnitude ∼50 Å in an approximately 70% strain relaxed In0.25Ga0.75As layers. The model is supported by atomic force microscopy (AFM) observations of cross-hatch morphology in the same composition samples grown well beyond the critical thickness for misfit dislocation generation.

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