Optically transparent SrTi_(1-x)Sb_(x)O_(3) (x=0.05, 0.10, 0.15, and 0.20) thin films with transmittances higher than 85 in the visible region have been grown on SrTiO_(3) substrates by pulsed-laser deposition. Unless overdoped, the films possess a single-crystal phase and impurity conduction. The temperature dependence of the resistivities shows a metal-semiconductor transition for the film with x=0.05, and semiconducting behaviors for the films with x=0.10 and 0.15. The overdoped film with x=0.20 is an insulator. Sb concentration has a dominant effect on the electrical properties of the films, and the Anderson localization is probably the mechanism. X-ray photoelectron spectroscopy results indicate that the Sb impurity atoms provide donor electrons to form impurity states within the band gap, which is responsible for the electrical localized impurity. The wide band gap and the low density of states in the conduction band result in the transparency of the films. The disorder increases with Sb concentration, which is the main origin of the evolution of the electrical properties.
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