Application of multistep formation during molecular beam epitaxy for fabricating novel nanomechanical structures

The technique of controlling the surface step distributions during molecular beam epitaxy has been widely used in the fabrication of semiconductor low-dimensional structures. In particular, the multistep structures formed via step bunching during growth are frequently applied for the growth of semiconductor quantum wires. This is a clean fabrication technique for semiconductor nanostructures that does not rely on lithographic processes, which often degrade crystalline quality. Here, we demonstrate, for the first time, the application of this "bottom-up" technique to the fabrication of semiconductor nanomechanical structures, which have the potential to bring about a revolution in the application of nanoscale fine-structure devices, such as high-resolution actuators and sensors, high-frequency signal processing components, and medical diagnostic devices.