Localized Strain Measurement in Molecular Beam Epitaxially Grown Chalcogenide Thin Films by Micro-Raman Spectroscopy.

ABSTRACT: We developed an experimental metrology for measuring local strain in molecular beam epitaxially (MBE) grown crystalline chalcogenide thin films through micro-Raman spectroscopy. For In₂Se₃ and Bi₂Se₃ on c-plane sapphire substrates, the transverse-optical vibrational mode (A₁ phonon) is most sensitive to strain. We first calibrated the phonon frequency-strain relationship in each material by introducing strain in flexible substrates. The Raman shift-strain coefficient is -1.97 cm^-1/% for the In₂Se₃ A₁(LO + TO) mode and -1.68 cm^-1/% for the Bi₂Se₃ A_1g ² mode. In₂Se₃ and Bi₂Se₃ samples exhibit comp

SUBMITTER: Li Q 

PROVIDER: S-EPMC7161023 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature