Abstract
We report the preparation and physical properties of reduced anatase TiO2-δ thin films obtained via a low-temperature (low-T) reduction using CaH2. The oxygen amounts were controlled in a wider range than ever reported. Some highly reduced anatase films showed resistivities as low as 10-3 Ω cm at room temperature, both in metallic and semiconducting states. The most conducting metallic sample has very high carrier concentration of 1.6×1021 cm-3, comparable with those of metal-doped anatase films. Moreover, the magnetoresistance of the films changed its sign twice as a function of δ.