Effect of rapid thermal annealing on thermoelectric thin films prepared by sputtering

Both n (Bi-Te) and p-type (Bi-Sb-Te) thermoelectric films were prepared on SiO₂/Si substrates by co-sputtering method and effects of post-annealing on their characteristic properties were investigated. Films with four different compositions were elaborated by adjusting the powers for each target. Thermal treatment of the films was performed using rapid thermal annealing. The post-deposition annealing was found to be very effective in improving the thermoelectric properties of both type films. Increase in thermopower was clearly observed for the films close to the stoichiometric composition. Recrystallization of chalcogenide phase has caused the enhancement of thermoelectric properties, along with the decrease of the carrier concentration