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A heteroepitaxial perovskite metal-base transistor


‘More than Moore’1 captures a concept for overcoming limitationsin silicon electronics by incorporating new functionalitiesin the constituent materials. Perovskite oxides are candidates because of their vast array of physical properties in a common structure. They also enable new electronic devices based on strongly-correlated electrons2. The field effect transistor3 and its derivatives have been the principal oxide devices investigated thus far4,5,6, but another option is available in a different geometry: if the current is perpendicular to the interface, the strong internal electric fields generated at back-to-back heterojunctions can be used for oxide electronics, analogous to bipolar transistors7. Here we demonstrate a perovskite heteroepitaxial metal-base transistor8 operating at room temperature, enabled by interface dipole engineering9. Analysis of many devices quantifies the evolution from hot-electron10 to permeable-base11 behaviour. This device provides a platform for incorporating the exotic ground states of perovskite oxides, as well as novel electronic phases at their interfaces12,13,14,15.

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Figure 1: Device fabrication and interface engineering.
Figure 2: Hot-electron transistor (HET) characteristics at 300 K.
Figure 3: Permeable base transistor (PBT) characteristics.
Figure 4: Permeable base transistor (PBT) in the high gain regime (α1).
Figure 5: Evolution of transistor operation.


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We thank J. H. Song and C. Bell for discussions. We acknowledge support from the TEPCO Research Foundation, and from the Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under contract DE-AC02-76SF00515 (H.Y.H.).

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T.Y. performed device fabrication, measurements, and data analysis. Y.H. and H.Y.H. assisted with the planning, measurements and analysis of the study.

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Correspondence to Harold Y. Hwang.

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The authors declare no competing financial interests.

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Yajima, T., Hikita, Y. & Hwang, H. A heteroepitaxial perovskite metal-base transistor. Nature Mater 10, 198–201 (2011).

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