Controllable fabrication of SiGe/Si and SiGe/Si/Cr helical nanobelts

Abstract

Helical nanobelts of SiGe/Si and SiGe/Si/Cr are fabricated by rolling up strained thin heterostructures. The fabrication involved electron beam lithography, reactive ion etching, and wet chemical etching steps followed by a drying procedure. All parameters of the helical nanobelts, namely their helical angle, chirality, pitch and diameter, are controllable in a reproducible fashion. The ease of fabrication of SiGe/Si and hybrid helical nanobelts opens new paths for the fabrication technology of micro- or nanoscale sensors, transducers, resonators and cylindrical shaped micro-capacitors.