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Mg segregation at inclined facets of pyramidal inversion domains in GaN:Mg.

ABSTRACT: Structural defects in Mg-doped GaN were analyzed using high-resolution scanning transmission electron microscopy combined with electron energy loss spectroscopy. The defects, in the shape of inverted pyramids, appear at high concentrations of incorporated Mg, which also lead to a reduction in free-hole concentration in Mg doped GaN. Detailed analysis pinpoints the arrangement of atoms in and around the defects and verify the presence of a well-defined layer of Mg at all facets, including the inclined facets. Our observations have resulted in a model of the pyramid-shaped defect, including structural displacements and compositional replacements, which is verified by image simulations. Finally, the total concentration of Mg atoms bound to these defects were evaluated, enabling a correlation between inactive and defect-bound dopants.

SUBMITTER: Persson AR

PROVIDER: S-EPMC9606308 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Mg segregation at inclined facets of pyramidal inversion domains in GaN:Mg.

Persson Axel R AR Papamichail Alexis A Darakchieva Vanya V Persson Per O Å POÅ

Scientific reports 20221026 1

Structural defects in Mg-doped GaN were analyzed using high-resolution scanning transmission electron microscopy combined with electron energy loss spectroscopy. The defects, in the shape of inverted pyramids, appear at high concentrations of incorporated Mg, which also lead to a reduction in free-hole concentration in Mg doped GaN. Detailed analysis pinpoints the arrangement of atoms in and around the defects and verify the presence of a well-defined layer of Mg at all facets, including the inc ...[more]

PMID: 36289429

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