The microstructure characterization disclosed that the post-annealing treatment drastically changed the microstructure of the films by instigating the development of a strong c-axis oriented texture. The electron mobility and Seebeck coefficient increase significantly, leading to a strong improvement in power factor from 3.3 μW/K2 cm for the as-deposited sample to 24.1 μW/K2 cm for the 200 oC-annealed sample.