High quality multifold Ge/Si/Ge composite quantum dots for thermoelectric materials
| Autor: | Hung Tai Chang, Jung Chao Hsu, Ming-Tsung Hung, Ching Chi Wang, Sheng Wei Lee, Pei-Wen Li |
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| Rok vydání: | 2013 |
| Předmět: |
Surface diffusion
Materials science Physics and Astronomy (miscellaneous) Phonon scattering Condensed matter physics business.industry technology industry and agriculture equipment and supplies Thermoelectric materials Isotropic etching Semiconductor Quantum dot Thermoelectric effect Thin film business |
| Zdroj: | Applied Physics Letters. 102:101902 |
| ISSN: | 1077-3118 0003-6951 |
| DOI: | 10.1063/1.4794943 |
| Popis: | We present an effective approach to grow high-quality thin film of composite quantum dots (CQDs) as a building block for thermoelectric materials, in which 3 times the usual Ge deposition can be incorporated within a 3-fold CQD. Selective chemical etching experiments reveal that a thin Si inserted layer in the CQDs modifies the growth mechanism through surface-mediated diffusion and SiGe alloying. Such thin-film-like CQD materials are demonstrated to exhibit reduced thermal conductivity κ⊥ with respect to the conventional QDs, perhaps as a consequence of enhanced diffusive phonon scattering from the high Si/Ge interface density and enhanced local alloying effect. |
| Databáze: | OpenAIRE |
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