All-perovskite transparent high mobility field effect using epitaxial BaSnO₃ and LaInO₃

We demonstrate an all-perovskite transparent heterojunction field effect transistor made of two lattice-matched perovskite oxides: BaSnO₃ and LaInO₃. We have developed epitaxial LaInO₃ as the gate oxide on top of BaSnO₃, which were recently reported to possess high thermal stability and electron mobility when doped with La. We measured the dielectric properties of the epitaxial LaInO₃ films, such as the band gap, dielectric constant, and the dielectric breakdown field. Using the LaInO₃ as a gate dielectric and the La-doped BaSnO₃ as a channel layer, we fabricated field effect device structure. The field effect mobility of such device was higher than 90 cm² V⁻¹ s⁻¹, the on/off ratio was larger than 10⁷, and the subthreshold swing was 0.65 V dec⁻¹. We discuss the possible origins for such device performance and the future directions for further improvement