Bulk Crystalline 4H-Silicon through a Metastable Allotropic Transition
| Autor: | Timothy A. Strobel, Jodie Bradby, Li Zhu, Brenton A. Cook, Thomas B. Shiell, Dougal G. McCulloch |
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| Rok vydání: | 2021 |
| Předmět: |
Materials science
Yield (engineering) Silicon General Physics and Astronomy chemistry.chemical_element 01 natural sciences Orientation (vector space) Crystallography chemistry Phase (matter) Metastability 0103 physical sciences Direct and indirect band gaps Absorption (logic) Crystallite 010306 general physics |
| Zdroj: | Physical review letters. 126(21) |
| ISSN: | 1079-7114 |
| Popis: | We report the synthesis of bulk, highly oriented, crystalline $4H$ hexagonal silicon ($4H\text{\ensuremath{-}}\mathrm{Si}$), through a metastable phase transformation upon heating the single-crystalline ${\mathrm{Si}}_{24}$ allotrope. Remarkably, the resulting $4H\text{\ensuremath{-}}\mathrm{Si}$ crystallites exhibit an orientation relationship with the ${\mathrm{Si}}_{24}$ crystals, indicating a structural relationship between the two phases. Optical absorption measurements reveal that $4H\text{\ensuremath{-}}\mathrm{Si}$ exhibits an indirect band gap near 1.2 eV, in agreement with first principles calculations. The metastable crystalline transition pathway provides a novel route to access bulk crystalline $4H\text{\ensuremath{-}}\mathrm{Si}$ in contrast to previous transformation paths that yield only nanocrystalline-disordered materials. |
| Databáze: | OpenAIRE |
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