Structure and transport in high pressure oxygen sputter-deposited BaSnO3-δ

BaSnO3 has recently been identified as a high mobility wide gap semiconductor with significant potential for room temperature oxide electronics. Here, a detailed study of the high pressure oxygen sputter-deposition, microstructure, morphology, and stoichiometry of epitaxial BaSnO3 on SrTiO3(001) and MgO(001) is reported, optimized conditions resulting in single-phase, relaxed, close to stoichiometric films. Most significantly, vacuum annealing is established as a facile route to n-doped BaSnO3-delta, leading to electron densities above 10(19) cm(-3), 5 m Omega cm resistivities, and room temperature mobility of 20 cm(2) V-1 s(-1) in 300-angstrom-thick films on MgO(001). Mobility limiting factors, and the substantial scope for their improvement, are discussed. (C) 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.