About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
|
Interface-mediated Phenomena in Structural Materials
|
Presentation Title |
Interfacial Reactions in Co/Bi2Te3 and Co/Bi2Se3 Couples |
Author(s) |
Sinn-wen Chen, Jia–Ruei Chang, He-cheng Ang |
On-Site Speaker (Planned) |
Sinn-wen Chen |
Abstract Scope |
Bi2Te3 and Bi2Se3 are important thermoelectric materials. To verify the suitability of Co as a barrier layer material in the modules made with Bi2Te3 and Bi2Se3 substrates, Co/Bi2Te3 and Co/Bi2Se3 couples are prepared and their interfacial reactions at 300℃ and 500℃ are examined. The phase equilibria isothermal sections of both Bi-Co-Te and Bi-Co-Se are also proposed for better illustration of the interfacial reaction phenomena. At 300℃, the reaction paths in the Co/Bi2Te3 and Co/Bi2Se3 are Co/CoTe/CoTe(Bi-rich)/(Bi2)m(Bi2Te3)n/Bi2Te3 and Co/Co1-xSex/(Bi2)m(Bi2Se3)n/ Bi2Se3. At 500℃, the respective reaction paths are Co/CoTe/CoTe(Bi-rich)/ (Bi2)m(Bi2Te3)n+Bi (Liquid)/Bi2Te3 and Co/Co1-xSex/Bi (liquid)/(Bi2)m(Bi2Se3)n/ Bi2Se3. In these two couples, Te and Se are the faster diffusion species. With faster diffusion out-fluxes of Te and Se from the substrates, the remaining Bi becomes molten at 500℃. |