Liquid-State Interfacial Reactions of Sn and Sn-Ag-Cu Solders with p-Type (Bi,Sb)2Te3 Thermoelectric Material
Autor: | Xin-He Wang, C.H. Chiu, Chao-hong Wang, Mei-hau Li |
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Rok vydání: | 2020 |
Předmět: |
Materials science
0211 other engineering and technologies General Engineering Intermetallic 02 engineering and technology Substrate (electronics) 021001 nanoscience & nanotechnology Thermoelectric materials Microstructure Chemical engineering Soldering Phase (matter) Thermoelectric effect General Materials Science 0210 nano-technology Dissolution 021102 mining & metallurgy |
Zdroj: | JOM. 72:3558-3566 |
ISSN: | 1543-1851 1047-4838 |
Popis: | Liquid-state interfacial reactions of p-type (Bi,Sb)2Te3 thermoelectric (TE) material with Sn and Sn-3.0 wt.%Ag-0.5 wt.%Cu (SAC305) solders, respectively, were examined at 250°C on a commercial highly orientated (Bi,Sb)2Te3 substrate with a (110) soldering plane. For the reactions with Sn, the initial reaction phase was the porous SnTe intermetallic compound (IMC). Then, a dense SnTe layer with many tiny cracks formed between the porous phase and TE substrate. With longer aging time, the dense SnTe gradually changed to the porous phase due to Sb dissolution. In the subsequent stage, the reaction phase zone included porous SnTe, an alternating layer microstructure of SnTe and liquid solder, and SnTe/Sn3Sb2 alternating layers from the solder to TE. The IMC growth was extremely fast, being approximately 15 μm/min, and nearly linear with aging time, suggesting reaction control. For the reactions with SAC305, a similar microstructure of porous SnTe and the dense layer was observed. Compared with the reactions with Sn, however, the IMC growth rate was greatly suppressed by ~ 80%. This can be attributed to the Ag-rich phase layer between the dense SnTe and (Bi,Sb)2Te3. Ag was verified to be the key element for dramatically changing the interfacial reaction behavior. |
Databáze: | OpenAIRE |
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