High-performance zinc antimonide thermoelectric thin films achieved by a layer-by-layer combination reaction approach

Zinc antimonide (Zn–Sb) is considered as a good candidate to replace the traditional TE materials due to its low cost, non-toxic, and high abundance of elements. In this work, layer-by-layer thin films were fabricated by sputtering Zn on the Sb precursor layer with a magnetron sputtering method, and an annealing process is performed on thin films to engage a self-assembled growth of Zn–Sb films. It is found that Zn–Sb film with good crystallinity was obtained after annealing at 300 ℃ for 10 min. Then, the influence of Zn layer thickness and annealing time on the structural, compositional, and thermoelectric properties for the Zn–Sb thin films were investigated. As a result, the thin film with mixed Zn 4 Sb 3 /ZnSb phases achieved a high power factor of 3.42 µWcm −1 K −2 when the Zn layer thickness was 600 nm. Additionally, the power factor was further optimized to 3.80 µWcm −1 K −2 after prolonging the annealing time up to 15 min.