Fabrication of flexible thin-film thermoelectric generators

Bismuth-telluride-based alloy thin film thermoelectric generators have excellent thermoelectric performance at room temperature. A traditional method of thermal evaporation is used to deposit thin films of bismuth-telluride-based alloys. The composition of the thin films of bismuth-telluride-based alloys is controlled by the deposition rate when sintered blocks of bismuth-telluride-based alloys are prepared as evaporated material sources. The deposition rate of n-type and p-type layers can be confirmed by material analysis and an electric conductivity measurement. The n-type layer with a low deposition rate and the p-type layer with a high deposition rate can fabricate thermoelectric generators with high performance. The fan-shaped layouts of n-type and p-type layers are integrated with the heat sinks of large aluminum pads to miniaturize thermoelectric generators on flexible polyimide substrates.