Dynamics of Periodic Step-Bunching During Growth on Vicinal GaAs(110) Surfaces: Computer Simulations and Experiments

AbstractMolecular beam epitaxial growth on GaAs(110) vicinal surfaces results in the formation of periodic micro-facets. We compare experimental results with computer simulations of a simple one dimensional step-flow growth model. The simulations show that preferential adatom attachment to the down step in a step array results in the destruction of step uniformity. A kinetic limitation due to adatom diffusion length along the terraces leads to stabilization of a periodic array of step-bunches. We extend our simulations to show the effects of the attachment and diffusion parameters on the dynamics of facet evolution.

Download Full-text

Development of Anisotropic GaAs (001) Surface Morphology During Molecular Beam Epitaxial Growth

MRS Proceedings ◽

10.1557/proc-317-53 ◽

1993 ◽

Vol 317 ◽

Cited By ~ 4

Author(s):

Allan J. Pidduck ◽

G.W. Smith ◽

A.M. Keir ◽

C.R. Whitehouse

Keyword(s):

Molecular Beam Epitaxy ◽

Surface Morphology ◽

Molecular Beam ◽

Step Flow ◽

Molecular Beam Epitaxial ◽

Amplitude Increase ◽

Roughness Amplitude ◽

Step Density ◽

Molecular Beam Epitaxial Growth ◽

Step Flow Growth

ABSTRACTWe have studied the development of a microscopically ridged [110] Morphology during (001) GaAs Molecular beam epitaxy, as a function of layer thickness and growth temperature. The ridge slopes are consistent with the [110] separation required to incorporate a majority of adatoms by step-flow growth. Thus step-flow can be a dominant growth mode even on nominally on-axis (singular) substrates. With increasing epilayer thickness, the ridge slopes, and surface step density, remain approximately constant, while the ridge spacings, and therefore roughness amplitude, increase steadily.

Download Full-text

ChemInform Abstract: IMPURITY DOPANT INCORPORATION AND DIFFUSION DURING MOLECULAR BEAM EPITAXIAL GROWTH OF IV-VI SEMICONDUCTORS

Chemischer Informationsdienst ◽

10.1002/chin.197914008 ◽

1979 ◽

Vol 10 (14) ◽

Author(s):

D. L. SMITH ◽

V. Y. PICKHARDT

Keyword(s):

Epitaxial Growth ◽

Molecular Beam ◽

Molecular Beam Epitaxial ◽

Dopant Incorporation ◽

Molecular Beam Epitaxial Growth ◽

And Diffusion

Download Full-text

The Dynamics Of Reflection High Energy Electron Diffraction Intensity Behaviour As A Probe Of Crystal Growth: Computer Simulations And Measurements During Molecular Beam Epitaxial Growth Of GaAs/AlXGa1-XAs(100)

10.1117/12.946322 ◽

1985 ◽

Cited By ~ 4

Author(s):

A. Madhukar ◽

S. V. Ghaisas ◽

T. C. Lee ◽

M. Y. Yen ◽

P. Chen ◽

...

Keyword(s):

Crystal Growth ◽

Electron Diffraction ◽

Epitaxial Growth ◽

Computer Simulations ◽

Molecular Beam ◽

High Energy ◽

High Energy Electron ◽

Diffraction Intensity ◽

Molecular Beam Epitaxial ◽

Molecular Beam Epitaxial Growth

Download Full-text

Molecular Beam Epitaxial Growth of (Al,Ga)As Tilted Superlattices on Vicinal GaAs (110)

MRS Proceedings ◽

10.1557/proc-237-473 ◽

1991 ◽

Vol 237 ◽

Cited By ~ 7

Author(s):

Mohan Krishnamurthy ◽

M. Wassermeier ◽

H. Weman ◽

J. L. Merz ◽

P. M. Petroffa

Keyword(s):

Quantum Wells ◽

Molecular Beam ◽

Growth Conditions ◽

Vicinal Surface ◽

Vicinal Surfaces ◽

Island Growth ◽

Quantum Well Structures ◽

Molecular Beam Epitaxial ◽

Transmission Electron ◽

Molecular Beam Epitaxial Growth

ABSTRACTA study of the molecular beam epitaxial (MBE) growth on singular and vicinal (110) surfaces of GaAs is presented. Quantum well structures and tilted superlattices (TSL) were grown on substrates misoriented 0.5°-2° towards the nearest [010] and [111]A azimuths at growth temperatures ranging from 450° C to 600° C under different growth conditions. The structures were characterized by Nomarski optical microscopy, transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy.Two types of faceting were observed on the surfaces. The structures grown at temperatures above 540°C and As beam fluxes below l×10-5 torr showed V-shaped facets pointing in the [001] direction and are attributed to As deficient island growth. Lower temperatures and higher As beam fluxes lead to surfaces with microfacets that are elongated along the respective step directions on the vicinal surface and are due to step bunching during growth. Their density and height decrease with decreasing vicinal angle and they disappear on the singular (110) surface. The photoluminescence of the GaAs quantum wells grown on these samples is redshifted with respect to that of the quantum wells grown on the flat surface. This is being ascribed to the fact that on the vicinal surface, the recombination takes place at the facets where the quantum wells are wider.The contrast in the TEM images of the TSL show for the samples misoriented towards [010] that the lateral segregation to the step edges on this surface is appreciable. The TSL spacing and the tilt however show that during growth the vicinal surfaces tend towards a surface with smaller miscut.

Download Full-text