Thermoelectric properties of Sb ₂Te ₃ thin films by electron beam evaporation

This study applies the thermoelectric grains of Sb ₂Te ₃ on conductive glass to evaporate Sb ₂Te ₃ thin films by the electron beam evaporation method. Through experimental tests with different evaporation process parameters and film annealing conditions, thin films with better Seebeck coefficient, resistivity (ρ) and power fact (PF) can be obtained. Experimental results show that when thin films are annealed, their defects can be decreased accordingly, and carrier mobility can be enhanced to further elevate the conductivity of thin films. When the substrate temperature is set at 200 °C to fabricate Sb ₂Te ₃ thin films by the evaporation process and by annealing at 220 °C for 60 minutes, the Seebeck coefficient of Sb ₂Te ₃ thin films increase from 87.6 μV/K to 177.7 μV/K; resistivity falls from 6.21 mω-cm to 2.53 mω-cm and PF can achieve the maximum value of 1.24 10- ³ W/K ² m. Finally, this study attempts to add indium (In) to Sb ₂Te ₃ thin films. Indium has been successfully fabricated In ₃SbTe ₂ thin films. This study also analyzes the effects of In on the thermoelectric properties of In ₃SbTe ₂ thin films.