Influence of post deposition annealing on thermoelectric properties of In2Se3 thin films

In the present work, thermoelectric properties of thin films of In2Se3 are explored, with its low thermal con-ductivity and high electrical conductivity simultaneously, reported for the bulk ceramics and improved results for the doped systems for both cation and anion sites. Here, In2Se3 thin films are grown using thermal evapo-ration technique and the effect of post deposition annealing on the thermoelectric properties of In2Se3 thin films are studied. XRD, Raman and UV-visible spectroscopy show that the as grown film corresponds to alpha-In2Se3 phase which gets transformed to the gamma-phase of In2Se3 upon annealing at 300 degrees C. The Hall measurements indicate that the films exhibit a high electron mobility and electrical conductivity. 3o)-method is employed for the thermal conductivity measurements of the as grown thin films of In2Se3 which is found to be 0.75 Wm- 1K-1. Thermo-electric properties including the power factor and the ZT values are found to reach as high as 12.04 IW m- 1K-2 and 4.9 x 10-3 respectively for the films post annealed at 300 degrees C. Our findings pave the simple way of energy generation based on the waste heat dissipation with the device size of few nm for the next generation device applications.

Automated summary

This study explores the thermoelectric properties of In2Se3 thin films, which have both low thermal conductivity and high electrical conductivity. The results show improved properties for doped systems on both cation and anion sites. In2Se3 thin films were grown using thermal evaporation technique and the effect of post deposition annealing on their thermoelectric properties was studied. The findings demonstrate high electron mobility, electrical conductivity, power factor, and ZT values for the annealed films at 300 degrees C.