Devices that confine and process single electrons represent an important scaling limit of electronics. Such devices have been realized in a variety of materials and exhibit remarkable electronic, optical and spintronic properties. Here, we use an atomic force microscope tip to reversibly 'sketch' single-electron transistors by controlling a metal-insulator transition at the interface of two oxides. In these devices, single electrons tunnel resonantly between source and drain electrodes through a conducting oxide island with a diameter of ∼1.5 nm. We demonstrate control over the number of electrons on the island using bottom- and side-gate electrodes, and observe hysteresis in electron occupation that is attributed to ferroelectricity within the oxide heterostructure. These single-electron devices may find use as ultradense non-volatile memories, nanoscale hybrid piezoelectric and charge sensors, as well as building blocks in quantum information processing and simulation platforms.

The fabrication, characterization, and optimization of large area rolled-up ultracompact nanomembrane-based capacitor arrays is demonstrated by combining bottom-up and top-down fabrication methods. The scalability of the process is tested on a 4-inch wafer platform where 1600 devices are manufactured in parallel. By using a hybrid dielectric layer consisting of HfO 2 and TiO 2 incorporated into an Al 2 O 3 matrix, rolled-up ultracompact capacitors can have their capacitance per footprint area increased by over two orders of magnitude. Their electrical properties can be precisely controlled by adjusting the oxide composition. Furthermore, the rolling of large-area nanomembranebased structures naturally results in a substantial decrease of the occupied footprint area. Such electrostatic rolled-up ultracompact energy-storage elements have a large potential in powering various autonomous microsystems.

Organic diodes consisting of molecular nano-pyramid structures sandwiched between metal and strained nano-membrane electrodes are created. The robust and smooth contacts provided by self-curled metal layers render the molecular nano-pyramids efficent channels for detecting nitrogen dioxide airflow.