Thermoelectric transport- and Hall measurements of low defect Sb2Te3 thin films grown by Atomic Layer Deposition
Sb2Te3 has recently been an object of intensive research since its promising applicability in thermoelectric, in phase-change memory devices and as a topological insulator. In this work, we report highly textured Sb2Te3 thin films, grown by atomic layer deposition on Si/SiO2 wafers based on the reaction of SbCl3 and (Et3Si)2Te. The low deposition temperature at 80 °C allows the pre-patterning of the Sb2Te3 by standard lithography processes. A platform to characterize the Seebeck coefficient S, the electrical conductivity σ as well as the Hall coefficient RH on the same film has been developed. Comparing all temperature-dependent transport properties, three different conductive regions in the temperature range of 50–400 K are found. Room temperature values of S = 146 × 10–6 VK−1, σ = 104 Sm−1 and mobility µ = 270.5 × 10−4 m2 V−1 s−1 are determined. The low carrier concentration in the range of n = 2.4 × 1018 cm−3 at 300 K quantifies the low defect content of the Sb2Te3 thin films.