Wide bandgap BaSnO3 films with room temperature conductivity exceeding 104 S cm−1

TLDR

Wide‑bandgap perovskite oxides that combine high room‑temperature conductivity with high mobility are sought after as transparent conductors and power‑electronics components. The authors grew n‑type BaSnO₃ films by hybrid molecular‑beam epitaxy achieving >10⁴ S cm⁻¹, and modeled temperature‑dependent mobility and Seebeck coefficients with Boltzmann transport and ab‑initio calculations to probe scattering mechanisms. The resulting films exhibit room‑temperature conductivity exceeding 10⁴ S cm⁻¹, mobilities up to 120 cm² V⁻¹ s⁻¹ at carrier densities above 3 × 10²⁰ cm⁻³, a 3‑eV bandgap, and position perovskite oxides on par with III‑N, advancing all‑transparent high‑power oxide electronics.

Abstract

Abstract Wide bandgap perovskite oxides with high room temperature conductivities and structural compatibility with a diverse family of organic/inorganic perovskite materials are of significant interest as transparent conductors and as active components in power electronics. Such materials must also possess high room temperature mobility to minimize power consumption and to enable high-frequency applications. Here, we report n-type BaSnO 3 films grown using hybrid molecular beam epitaxy with room temperature conductivity exceeding 10 4 S cm −1 . Significantly, these films show room temperature mobilities up to 120 cm 2 V −1 s −1 even at carrier concentrations above 3 × 10 20 cm −3 together with a wide bandgap (3 eV). We examine the mobility-limiting scattering mechanisms by calculating temperature-dependent mobility, and Seebeck coefficient using the Boltzmann transport framework and ab-initio calculations. These results place perovskite oxide semiconductors for the first time on par with the highly successful III–N system, thereby bringing all-transparent, high-power oxide electronics operating at room temperature a step closer to reality.