Enhanced thermoelectric properties of metal film on bismuth telluride-based materials
| Autor: | Ping Hsing Yang, Ren Jye Wu, Jenn Yeu Hwang, Wen Hsuan Chao, Shih Chun Tseng, Yi Ray Chen |
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| Rok vydání: | 2014 |
| Předmět: |
Materials science
Diffusion barrier Metallurgy Metals and Alloys Analytical chemistry Energy-dispersive X-ray spectroscopy chemistry.chemical_element Surfaces and Interfaces Thermoelectric materials Surfaces Coatings and Films Electronic Optical and Magnetic Materials Bismuth chemistry.chemical_compound Thermoelectric generator chemistry Thermoelectric effect Materials Chemistry Bismuth telluride Thin film |
| Zdroj: | Thin Solid Films. 570:172-177 |
| ISSN: | 0040-6090 |
| DOI: | 10.1016/j.tsf.2014.04.025 |
| Popis: | Diffusion barriers have a significant influence on the reliability and life time of thermoelectric modules. Although nickel is commonly used as a diffusion barrier in commercial thermoelectric modules, several studies have verified that Ni migrates to bismuth telluride-based material during high temperature cycles and causes a loss in efficacy. In this paper, the influence of metal layers coated to p-type and n-type Bi 2 Te 3 on the interface characterization and thermoelectric property is studied using a RF magnetron sputtering. The findings from this study demonstrate the structural and thermoelectric properties of p-type and n-type Bi 2 Te 3 coated with different metal layers. The crystalline phase and compositional change of the interface between the Bi 2 Te 3 materials and the metal layers were determined using an X-ray diffractometer and scanning electron microscopy with energy dispersive spectroscopy. Formation of NiTe was observed in the sample of Ni/p-type Bi 2 Te 3 based films post-annealed in an N 2 atmosphere at 200 °C. In contrast, no Co x Te y was formed in the sample of Co/p-type Bi 2 Te 3 based films post-annealed at 200 °C. For as-deposited Ni/p-type and n-type Bi 2 Te 3 based legs, the Ni slightly diffused into the Bi 2 Te 3 based legs. A similar phenomenon also occurred in the as-deposited Co/p-type and n-type Bi 2 Te 3 based legs. The Seebeck coefficients of the Co contacts on the Bi 2 Te 3 based material displayed better behavior than those of the Ni contacts on the Bi 2 Te 3 based legs. Thus Co could be a suitable diffusion barrier for bulk Bi 2 Te 3 based material. The observed effects on the thermoelectric and structural properties of metal/Bi 2 Te 3 based material are crucial for understanding the interface between the diffusion barrier and thermoelectric materials. |
| Databáze: | OpenAIRE |
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