Use of nonpolar BaHfO$_{3}$ gate oxide for field effect on the high mobility BaSnO$_{3}$

Recently, BaSnO$_{3}$ (BSO) has attracted attentions as a transparent conducting oxide and/or a transparent oxide semiconductor due to its novel properties: the excellent oxygen stability even at high temperature and the high electrical mobility at room temperature. We fabricated field effect transistors using La-doped BSO as the semiconducting channel on undoped BSO buffer layers on SrTiO$_{3}$ substrates. A non-polar perovskite BaHfO$_{3}$ was used as the gate insulator, and 4{\%} La-doped BSO as the source, the drain, and the gate electrodes grown by pulsed laser deposition. We have measured the optical and the dielectric properties of the epitaxial BaHfO$_{3}$ gate oxide layer, namely the optical band gap, the dielectric constant, and the breakdown field. Using such BaHfO$_{3}$ gate oxide, we observed carrier modulation in the active layer by field effect. In this presentation, we will report on the performance of such field effect transistors: the output and the transfer characteristics, the field effect mobility, the $I_{on}$/$I_{off}$ ratio, and the subthreshold swing.