"A heteroepitaxial perovskite metal-base transistor"

Takeaki Yajima: Yasuyuki Hikita and Harold Y. Hwang; Nature Materials, 01/23/11.

Additional Authors: Yasuyuki Hikita and Harold Y. Hwang


‘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.