The results of our study underscore that the electrical transport and thermoelectric properties of the films seem intimately con- nected to the microstructure evolution of the films upon annealing. First, the enhancement of the Seebeck coefficient with the anneal- ing temperature is probably due to the fact that the with their c axis oriented along the film normal have gained the domi nance upon annealing. Such texture effects on the thermoelectric properties were also observed in bulk 3-based thermoelectric materials, which are expected to display very anisotropic proper ties owing to their layered crystal structures addition, increase improvement seems also directly related to the of upon annealing at elevated temper Combination these effects arising from the microstructure changes appears to have led to the drastic increase in the power factor