The development of Bi₂Te₃ thin films has huge potential in the pursuit of efficient thermoelectric micro/nanodevices due to their high Seebeck coefficient, high electrical conductivity and low thermal conductivity. The optimization of experimental parameters of Bi-Te thin films produced by co-evaporation will be investigated in this study. Co-evaporation is a low cost, easy-to-control process which can be used for high throughput and is scalable. We found that an optimal Te/Bi ratio of 1.5 with good thermoelectric properties can be directly synthesized by Bi and Bi₂Te₃ co-evaporation. Compared to the conventional Bi/Te co-evaporation process, high temperature annealing or substrate heating is not necessary for the process mentioned in this paper, which is a desirable feature when using polymer-based substrates, organic/inorganic hybrid thermoelectric generators, and flexible devices since they have relatively low tolerance to heat. The optimized Bi₂Te₃ thin films, which are mixed phases of Bi₂Te₃, Bi₃Te₄ and Te, possess high carrier concentration (6.65 × 10²⁰ cm⁻³), low electrical resistivity (3.17 × 10⁻³ Ωcm), and extremely low thermal conductivity (0.59 W/mK) at room temperature on a smooth surface (roughness <5.5 nm) and are achieved by adjusting the deposition rate of Bi and Bi₂Te₃. The correlation between the structures of mixed phases, electrical and thermal properties will be discussed in detail.

Bi ₂ Te ₃薄膜的发展因其高塞贝克系数，高电导率和低热导率而在追求高效热电微/纳米器件方面具有巨大潜力。本研究将研究通过共蒸发制备的Bi-Te薄膜的实验参数的优化。共蒸发是一种低成本，易于控制的过程，可用于高通量且可扩展。我们发现，Bi和Bi ₂ Te ₃可以直接合成具有良好热电性能的最佳Te / Bi比为1.5。共蒸发。与常规的Bi / Te共蒸发工艺相比，本文提到的工艺不需要高温退火或基板加热，这在使用基于聚合物的基板，有机/无机混合热电发生器和柔性基板时是一个理想的功能。设备，因为它们具有相对较低的耐热性。优化的Bi ₂ Te ₃薄膜是Bi ₂ Te ₃，Bi ₃ Te ₄和Te的混合相，具有高载流子浓度（6.65×10 ²⁰  cm ^-3），低电阻率（3.17×10 ^-3）Ωcm），并且在室温下在光滑表面（粗糙度<5.5 nm）上具有极低的热导率（0.59 W / mK），这可以通过调节Bi和Bi ₂ Te ₃的沉积速率来实现。将详细讨论混合相的结构，电性质和热性质之间的相关性。