[19a-Z14-1~11] 6.3 酸化物エレクトロニクス

[19a-Z14-10] Field-effect transistor based on two-dimensional carrier gas at the FeO_y/SrTiO₃ interface

〇Anh Duc Le^1,2,3、Theodorus J. Wijaya¹、Shingo Kaneta-Takada¹、Masaaki Tanaka^1,4、Shinobu Ohya^1,2,4 (1.Dept of EEIS, Tokyo Univ.、2.IEI, Tokyo Univ.、3.PRESTO, JST、4.CSRN, Tokyo Univ.)

キーワード：perovskite oxides, two dimensional hole gas, field effect transistor

Our recent discovery of both isolated two dimensional (2D) hole gas (2DHG) and 2D electron gas (2DEG) with ultrahigh mobilities at FeO_y/SrTiO₃ interfaces [1] paves a novel way to realize oxide-based devices such as diodes and transistors. Here, as a proof of concept, we demonstrate field-effect transistor (FET) operation using the 2DHG on SrTiO₃ substrates with a back-gate configuration. At low temperatures (~3.5 K), these FET devices exhibit excellent performance, with subthreshold swing values of ~30 mV/dec and on-off ratios of ~10⁷. We found that the underlying mechanism for this high-performance switching involves a tunneling process at the pn junctions. Refs: [1] L. D. Anh et al., Adv. Mater. 32, 1906003 (2020).