Experimental and theoretical investigation into the difficulties of thallium incorporation into III-V semiconductors
| Autor: | G. Hollinger, Ph. Regreny, R. Beneyton, Catherine Priester, Geneviève Grenet, Bruno Canut, Michel Gendry |
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| Přispěvatelé: | Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF) |
| Jazyk: | angličtina |
| Rok vydání: | 2005 |
| Předmět: |
Diffraction
Materials science Alloy chemistry.chemical_element 02 engineering and technology engineering.material 01 natural sciences Condensed Matter::Materials Science 0103 physical sciences Thin film 010302 applied physics Condensed matter physics Condensed Matter::Other business.industry Doping Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 021001 nanoscience & nanotechnology Condensed Matter Physics Electronic Optical and Magnetic Materials Semiconductor chemistry engineering Thallium 0210 nano-technology business Surface reconstruction Molecular beam epitaxy |
| Zdroj: | Physical Review B: Condensed Matter and Materials Physics (1998-2015) Physical Review B: Condensed Matter and Materials Physics (1998-2015), American Physical Society, 2005, 72, pp.125209-1-10 Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2005, 72, pp.125209-1-10 |
| ISSN: | 1098-0121 1550-235X |
| Popis: | The aim of this paper is to show---from both an experimental and a theoretical point of view---why it is so difficult to incorporate thallium into III-V semiconductors. The experimental part describes how ${\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Tl}}_{x}\mathrm{As}$ epilayers on GaAs(001) and ${\mathrm{In}}_{1\ensuremath{-}x}{\mathrm{Tl}}_{x}\mathrm{As}$ epilayers on InAs(001) can be obtained using molecular beam epitaxy (MBE). Tl is found to be much easier to incorporate into GaAs (7% over 50 nm) than into InAs (2.5% over 50 nm) despite the higher elastic stress in the former than in the latter. Once pseudomorphic ${\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Tl}}_{x}\mathrm{As}$ epilayers of sufficient thickness have been successfully obtained, the lattice and elastic parameters for the Tl-As bonding in ${\mathrm{Ga}}_{1\ensuremath{-}x}{\mathrm{Tl}}_{x}\mathrm{As}$ alloys are deduced by combining results from double-crystal x-ray diffraction and Rutherford backscattering (RBS) spectrometry . The theoretical part proposes a tentative explanation---within Keating's valence force field framework---for the difficulties met when incorporating Tl into III-V compounds. When incorporated into either a GaAs or an InAs bulk matrix, the Tl atoms keep away from each other by avoiding being first neighbors in the III-element sublattice, but the magnitude of the phenomenon is clearly much smaller in the InAs case than in the GaAs case. However, this effect alone cannot explain the difference between GaAs and InAs versus Tl incorporation. Turning next to surface effects, the paper demonstrates that the dimers on the InAs surface are better stabilized by the presence of Tl than are those on the GaAs surface. Last, a stronger tendency to form diluted ordered alloy clusters for GaAs than for InAs is demonstrated, which could be a reason for the greater difficulties encountered when incorporating Tl into InAs matrix than into GaAs. |
| Databáze: | OpenAIRE |
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