Step-step interactions on GaAs (110) nanopatterns

Journal Article · Mon Jan 14 00:00:00 EST 2013 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4774215· OSTI ID:22102212

Galiana, B.; Benedicto, M.; Tejedor, P. ^[1]

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1. Instituto de Ciencia de Materiales de Madrid, C.S.I.C., Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain)

The step-step interactions on vicinal GaAs (110) surface patterns have been extracted from the quantitative analysis of the terrace width distribution (TWD). We have specifically studied the interactions in near-equilibrium faceting and kinetics-driven step bunching and meandering formed by spontaneous self-organization or through the modification of GaAs growth kinetics by atomic hydrogen. We show that the experimental TWDs determined from atomic force microscopy measurements can be accurately described by a weighed sum of a generalized Wigner distribution and several Gaussians. The results of our calculations indicate that straight facets are formed during high temperature homoepitaxy due to attractive interactions between [110] steps. At low temperatures, steady state attractive interactions in [110] step bunches are preceded by a transition regime dominated by entropic and energetic repulsions between meandering [11n]-type steps (n {>=} 2), whose population density exceeds that of the [110] bunched steps. In addition, it has been found that atomic H reduces the attractive interactions between [110] bunched steps and enhances entropic and dipole-induced energetic repulsions between H-terminated [11n] steps through the inhibition of As-As bond formation at step edges. Our analysis has evidenced a correlation between the value of the adjustable parameter that accounts in our model for the specific weight of the secondary peaks in the TWD ({beta}) and the extent of transverse meandering on the vicinal surface.

• OSTI ID: 22102212
• Journal Information: Journal of Applied Physics, Vol. 113, Issue 2; Other Information: (c) 2013 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
ATOMIC FORCE MICROSCOPY
CHEMICAL BONDS
CLEBSCH-GORDAN COEFFICIENTS
CRYSTAL GROWTH
DIPOLES
DISTRIBUTION
ENTROPY
EQUILIBRIUM
GALLIUM ARSENIDES
INTERACTIONS
LAYERS
MOLECULAR BEAM EPITAXY
POPULATION DENSITY
SEMICONDUCTOR MATERIALS
STEADY-STATE CONDITIONS
SURFACES
WIGNER DISTRIBUTION