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InP and AlInP(001)(2 × 4) Surface Oxidation from Density Functional Theory.

ABSTRACT: The atomic structure and electronic properties of the InP and Al_0.5In_0.5P(001) surfaces at the initial stages of oxidation are investigated via density functional theory. Thereby, we focus on the mixed-dimer (2 × 4) surfaces stable for cation-rich preparation conditions. For InP, the top In-P dimer is the most favored adsorption site, while it is the second-layer Al-Al dimer for AlInP. The energetically favored adsorption sites yield group III-O bond-related states in the energy region of the bulk band gap, which may act as recombination centers. Consistently, the In p state density around the conduction edge is found to be reduced upon oxidation.

SUBMITTER: Ruiz Alvarado IA

PROVIDER: S-EPMC7948233 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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InP and AlInP(001)(2 × 4) Surface Oxidation from Density Functional Theory.

Ruiz Alvarado Isaac Azahel IA Karmo Marsel M Runge Erich E Schmidt Wolf Gero WG

ACS omega 20210225 9

The atomic structure and electronic properties of the InP and Al0.5In0.5P(001) surfaces at the initial stages of oxidation are investigated via density functional theory. Thereby, we focus on the mixed-dimer (2 × 4) surfaces stable for cation-rich preparation conditions. For InP, the top In-P dimer is the most favored adsorption site, while it is the second-layer Al-Al dimer for AlInP. The energetically favored adsorption sites yield group III-O bond-related states in the e ...[more]

PMID: 33718720

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