Correlation between defects and conductivity of Sb-doped tin oxide thin films

Defects in undoped and antimony (Sb)-doped tin oxide thin films fabricated via a sol-gel method have been investigated using a slow positron beam by which an annihilation lineshape parameter is used to evaluate defects in the films. With increasing calcination temperature, the resistivity for undoped films increased because of removal of oxygen vacancies in them; however, the resistivity gradually declined for Sb-doped films upon annealing at higher temperatures, mainly due to weakened carrier scattering with fewer residual defects. The results show that defects as well as dopants play an important role in determining the resistivity of tin oxide films.