Publications Details

Barrier/bonding layers on bismuth telluride (Bi 2Te 3) for high temperature thermoelectric modules

Lin, Wen P.; Wesolowski, Daniel E.; Lee, Chin C.

In this research, a fundamental study is conducted to identify the materials and develop the processes for producing barrier/bonding composite on Bi 2Te 3 for high temperature thermoelectric applications. The composite must meet four basic requirements: (a) prevent interdiffusion between the electrode material, for our design, silver(Ag) and Bi 2Te 3, (b) bond well to Bi 2Te 3, (c) bond well to Ag electrode, and (d) do not themselves diffuse into Bi 2Te 3. The composites investigated include palladium (Pd), nickel/gold (Ni/Au), Ag, and titanium/gold (Ti/Au). After annealing at 250 °C for 200 h, only the Ti/Au design meets all four requirements. The thickness of Ti and Au, respectively, is only 100 nm. Other than meeting these four requirements, the Ti/Au layers exhibit excellent step coverage on the rough Bi 2Te 3 surface even after the annealing process. © The Author(s) 2011.