BaSnO3

BaSnO3 is a wide-bandgap perovskite oxide with the chemical formula BaSnO3. It crystallizes in the cubic perovskite structure at room temperature, with Ba2+ on the A-site, Sn4+ on the B-site, and oxygen on the O sites, forming a network of corner-sharing SnO6 octahedra. The material is an n-type semiconductor with a bandgap around 3.1 eV. The conduction band minimum is dominated by Sn 5s states, while the valence band arises mainly from O 2p orbitals.

BaSnO3 exhibits high apparent electron mobility when doped, among oxide semiconductors. La-doped BaSnO3 (BLSO) and Nb- or Sb-doped variants show high room-temperature mobilities, with reports of over 100 cm2/Vs and, in high-quality films, approaching several hundred cm2/Vs, contingent on growth conditions and defect levels. Its wide bandgap also makes it highly transparent in the visible spectrum.

Synthesis and doping are well developed: BaSnO3 can be prepared by solid-state routes from BaCO3 and SnO2, or via solution-based methods and thin-film processes. Epitaxial thin films are grown by pulsed laser deposition, molecular-beam epitaxy, or sputtering on lattice-matched substrates. Dopants such as La3+ on the Ba site and Nb5+/Sb5+ on the Sn site donate electrons to the conduction band; oxygen vacancies can also contribute free carriers.

Applications and research focus include transparent conducting oxides for transparent electronics, UV photodetectors, and oxide heterostructures that benefit from high-mobility n-type channels. Challenges include dopant solubility limits, defect scattering, and achieving scalable, high-quality large-area films with stable performance.