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Computing with DFT Band Offsets at Semiconductor Interfaces: A Comparison of Two Methods.

ABSTRACT: Two DFT-based methods using hybrid functionals and plane-averaged profiles of the Hartree potential (individual slabs versus vacuum and alternating slabs of both materials), which are frequently used to predict or estimate the offset between bands at interfaces between two semiconductors, are analyzed in the present work. These methods are compared using several very different semiconductor pairs, and the conclusions about the advantages of each method are discussed. Overall, the alternating slabs method is recommended in those cases where epitaxial mismatch does not represent a significant problem.

SUBMITTER: Conesa JC

PROVIDER: S-EPMC8235794 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Computing with DFT Band Offsets at Semiconductor Interfaces: A Comparison of Two Methods.

Conesa José C JC

Nanomaterials (Basel, Switzerland) 20210616 6

Two DFT-based methods using hybrid functionals and plane-averaged profiles of the Hartree potential (individual slabs versus vacuum and alternating slabs of both materials), which are frequently used to predict or estimate the offset between bands at interfaces between two semiconductors, are analyzed in the present work. These methods are compared using several very different semiconductor pairs, and the conclusions about the advantages of each method are discussed. Overall, the alternating sla ...[more]

PMID: 34208486

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