Vertical Transport Control of Electrical Charge Carriers in Insulator/Oxide Semiconductor Hetero-structure

The technology for electrical current passing through an insulator thin-film between two electrodes is newly getting spotlights for substantial potentials toward advanced functional devices including a diode and a resistive switching device. However, depending on an electrode-limited conduction mechanisms of the conventional devices, a narrow processing window for a thickness of the insulator thin-film and an inability to control a magnitude and direction of the currents are challenges to overcome. Herein, we report a new approach to enable electrical charge carriers to pass stably through a relatively-thick insulator layer and to control a magnitude and polarity of the currents by applying an oxide semiconductor electrode in a metal/insulator/metal structure. We reveal that the electrical conduction in our devices follows a space charge-limited conduction mechanism which mainly depends …