skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Halogen diffusion on a Ga-stabilized ζ-GaAs(001)–(4 × 2) surface

Abstract

The atomic and electronic structure of a Ga-stabilized GaAs(001) surface with the ζ(4 × 2) reconstruction and halogens in a number of symmetric sites on the surface are calculated by the plane-wave projector augmented wave method. The energy barriers of halogen-atom diffusion on this surface are calculated, which allow determination of the most preferred paths of their migration. It is shown that there is a low barrier (0.17–0.23 eV) for the diffusion of all halogens under consideration (I, Br, Cl, F) along the surface gallium dimer, whereas the barrier is significantly higher for diffusion between adjacent gallium dimers. In general, the energy barriers for halogen diffusion in both directions ([110] and [1-10]) point to their high surface mobility, despite high binding energies at a number of surface adsorption sites.

Authors:
;  [1]
  1. Russian Academy of Sciences, Institute of Strength Physics and Materials Science, Siberian Branch (Russian Federation)
Publication Date:
OSTI Identifier:
22649715
Resource Type:
Journal Article
Resource Relation:
Journal Name: Semiconductors; Journal Volume: 50; Journal Issue: 9; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ADSORPTION; BINDING ENERGY; CARRIER MOBILITY; CRYSTAL STRUCTURE; DIFFUSION BARRIERS; DIMERS; ELECTRONIC STRUCTURE; GALLIUM; GALLIUM ARSENIDES; HALOGENS; SURFACES

Citation Formats

Bakulin, A. V., E-mail: bakulin@ispms.tsc.ru, and Kulkova, S. E. Halogen diffusion on a Ga-stabilized ζ-GaAs(001)–(4 × 2) surface. United States: N. p., 2016. Web. doi:10.1134/S1063782616090049.
Bakulin, A. V., E-mail: bakulin@ispms.tsc.ru, & Kulkova, S. E. Halogen diffusion on a Ga-stabilized ζ-GaAs(001)–(4 × 2) surface. United States. doi:10.1134/S1063782616090049.
Bakulin, A. V., E-mail: bakulin@ispms.tsc.ru, and Kulkova, S. E. 2016. "Halogen diffusion on a Ga-stabilized ζ-GaAs(001)–(4 × 2) surface". United States. doi:10.1134/S1063782616090049.
@article{osti_22649715,
title = {Halogen diffusion on a Ga-stabilized ζ-GaAs(001)–(4 × 2) surface},
author = {Bakulin, A. V., E-mail: bakulin@ispms.tsc.ru and Kulkova, S. E.},
abstractNote = {The atomic and electronic structure of a Ga-stabilized GaAs(001) surface with the ζ(4 × 2) reconstruction and halogens in a number of symmetric sites on the surface are calculated by the plane-wave projector augmented wave method. The energy barriers of halogen-atom diffusion on this surface are calculated, which allow determination of the most preferred paths of their migration. It is shown that there is a low barrier (0.17–0.23 eV) for the diffusion of all halogens under consideration (I, Br, Cl, F) along the surface gallium dimer, whereas the barrier is significantly higher for diffusion between adjacent gallium dimers. In general, the energy barriers for halogen diffusion in both directions ([110] and [1-10]) point to their high surface mobility, despite high binding energies at a number of surface adsorption sites.},
doi = {10.1134/S1063782616090049},
journal = {Semiconductors},
number = 9,
volume = 50,
place = {United States},
year = 2016,
month = 9
}
  • Halogen (F, Cl, Br, and I) adsorption at an As-stabilized GaAs (001) surface with the β2–(2 × 4) reconstruction is studied using the plane-wave projected-augmented wave method. The effect of halogens on the structural and electronic characteristics of the semiconductor surface is analyzed. The T{sub 2}′ site at the missing row edge is shown to be the energetically most favorable for the adsorption of F, Cl, and Br, whereas I prefers the H{sub 3} site between adjacent arsenic dimers in the third layer from the surface. Ga-halogen bond formation suggests that charge is transferred via the depletion of occupied orbitalsmore » of the As-dimer surface atoms, which leads to the weakening of Ga–As bonds in the substrate. The weakening of bonds between substrate-surface atoms due to the interaction of halogens with the surface is estimated.« less
  • No abstract prepared.
  • The authors investigate the low-temperature codiffusion of Ni, Ga, and As in the surface layer of gallium arsenide and study its effect on the current-voltage characteristics of a Ni/GaAs rectifier contact. The concentration distribution of atoms in the function layer of a Ni-GaAs system was investigated by the methods of layerwise radiometric and neutron-activation analyses. It was found that interdiffusion of components takes place in the Ni-GaAs system in an elastic stress field, generated by the differences in the lattice parameters and thermal-expansion coefficients of Ni, GaAs, and the intermetallic compound which form. The form and parameters of the current-voltagemore » characteristics of a Ni/GaAs contact are determined by the phase composition and the structure of the junction layer.« less
  • Surface diffusion is shown to be the important factor in sputter--induced ripple and cone development on GaAs and InP surfaces for conditions typical of depth profiling when using surface analysis techniques. Ripple formation has been observed on both GaAs and InP when sputtered using Cs{sup +} and O{sup +}{sub 2} ion beams. For GaAs, the ripple wavelength'' increases with sample temperature in the range from 45 to 100 {degree}C, in qualitative agreement with the surface diffusion model of Bradley and Harper. No ripple formation is observed when the GaAs sample is cooled to {minus}30 {degree}C where surface diffusion is limited,more » or heated above 100 {degree}C, where a proposed surface phase change may alter the diffusion rate. Ripple development also occurs on InP, but it is impossible to observe at 100 {degree}C due to extensive cone formation. At this elevated temperature, Ar{sup +} sputtering of InP leads to a surface enrichment of indium that is accompanied by a change in the In {ital M}{sub 4,5}{ital N}{sub 4,5}{ital N}{sub 4,5} Auger line shape toward that for indium metal. This result, together with the observation that cone formation is eliminated for sputtering at {minus}20 {degree}C, supports the {ital intrinsic} model where sputtering causes indium enrichment and surface diffusion that results in the agglomeration of indium metal into clusters. These clusters produce cone formation, possibly through the difference in sputter rates of indium and InP.« less
  • Faceted surface morphologies of homoepitaxial films grown on exactly ([bar 1][bar 1][bar 1])-oriented GaAs substrates in the [radical]19 [times][radical]19 regime are studied with an atomic force microscope. The facets are composed of three vicinal surfaces tilted about 2[degree] toward [2[bar 1][bar 1]], [[bar 1]2[bar 1]], and [[bar 1][bar 1]2] directions, respectively. The diffusion length at the growth condition is estimated from the surface morphologies and found to be at least hundreds of nanometers. It is comparable to the diffusion length on the (100) surface grown under the same conditions. Therefore, the facet formation on GaAs ([bar 1][bar 1][bar 1]) filmmore » is unlikely caused by slower surface mobility.« less