On the electron mobility and the donor centres in reduced and lithium-doped rutile (TiO2)

Abstract

Resistivity, Hall-and Seebeck-data of reduced and lithium-doped rutile both with and without alumina added are reported. The data are interpreted by a one band model. Anisotropy of the relaxation time must be taken explicitly into account. The donors in reduced rutile are probably titanium interstitials, which are multiple donors. The first and second of their ionization potentials are derived from the experimental data. Lithium is a single shallow donor. It is demonstrated that aluminium introduces more than one acceptor level. One of these levels is situated close to the conduction band.