Efficient Editing of Atomic-Scale Silicon Devices and Memories

A dangling bond (DB) on the surface of hydrogen-terminated silicon forms an atomic silicon quantum dot, localizing up to two electrons. Circuits based upon DBs can enable future device architectures. Among these are atomic scale logic devices, where they are predicted to reduce power consumption by several orders of magnitude. The fabrication of these devices requires the precise control over the placement of DBs to achieve proper functionality. Scanning Tunneling Microscopes (STMs) are employed to fabricate many of these devices. However, at the atomic scale fabrication presents unique challenges due to the extreme sensitivity to uncertainties in the STM tip position and geometry. These uncertainties can result in the creation of misplaced DBs during fabrication. Recently we’ve discovered several methods to cap individual DBs with single atoms of hydrogen to efficiently erase misplaced DBs and edit structures. This newfound ability has greatly improved our fabrication yields, allowing for the creation of truly prefect DB structures. With these techniques, new experiments and applications are now within reach, including ultra-high density, room-temperature stable memory.